626 terms

CPH Exam - Environmental Health Sciences

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Absorption (in biology)
Penetration of a substance into an organism and its cells by various processes, some specialized, some involving expenditure of energy (active transport), some involving a carrier system, and others involving passive movement down an electrochemical gradient.

Note: In mammals absorption is usually through the respiratory tract, gastrointestinal tract, or skin into the circulatory system and from the circulation into organs, tissues and cells.
Acceptable Risk
The risk that has minimal detrimental effects or for which benefits outweigh the potential hazards. Note: Calculated risk of an increase of one case in a million people per year for cancer is usually considered to be negligible.
Acid Deposition (Acid Rain)
Acidification occurs after the release of nitrogen oxide and sulfur dioxide from point or nonpoint sources into the atmosphere. Chemical processes may transform these chemicals into sulfuric and nitirc acids. These are returned to the earth in snowfall, rain, fog, and dust and may deposit at distances far from the original sources.
Acute Exposure
A single exposure to a toxic substance which may result in severe biological harm or death. Acute exposures are usually characterized as lasting no longer than a day, as compared to longer, continuing exposure over a period of time.
Additive effect
A biologic response to exposure to multiple substances that equals the sum of responses of all the individual substances added together [compare with antagonistic effect and synergistic effect ]
Adverse health effect
A change in body function or cell structure that might lead to disease or health problems
Aerobic
Life or processes that require, or are not destroyed by, the presence of oxygen. (See: anaerobic.)
Aerosol
Mixture of small droplets or particles (solid, liquid, or a mixed variety) and a carrier gas (usually air).
Agency for Toxic Substances and Disease Registry (ATSDR)
The Agency for Toxic Substances and Disease Registry (ATSDR) , based in Atlanta, Georgia, is a federal public health agency of the U.S. Department of Health and Human Services . ATSDR serves the public by using the best science, taking responsive public health actions, and providing trusted health information to prevent harmful exposures and diseases related to toxic substances.
Air Toxics
Any air pollutant for which a national ambient air quality standard (NAAQS) does not exist (i.e. excluding ozone, carbon monoxide, PM-10, sulfur dioxide, nitrogen oxide) that may reasonably be anticipated to cause cancer; respiratory, cardiovascular, or developmental effects; reproductive dysfunctions, neurological disorders, heritable gene mutations, or other serious or irreversible chronic or acute health effects in humans
Alpha particle
A positively charged particle ejected spontaneously from the nuclei of some radioactive elements. It is identical to a helium nucleus that has a mass number of 4 and an electrostatic charge of +2. It has low penetrating power and a short range (a few centimeters in air). The most energetic alpha particle will generally fail to penetrate the dead layers of cells covering the skin and can be easily stopped by a sheet of paper. Alpha particles are hazardous when an alpha-emitting isotope is inside the body.
Ambient Air
Any unconfined portion of the atmosphere: open air, surrounding air.
American Conference of Governmental Industrial Hygienists (ACGIH)
ACGIH ® is a member-based organization that advances occupational and environmental health. Examples of this include our annual editions of the TLVs ® and BEIs ® and work practice guides in ACGIH ® 's Signature Publications.
Anaerobic
life or process that occurs in, or is not destroyed by, the absence of oxygen.
Analyte
A substance that is undergoing analysis or is being measured. For example, if the analyte is mercury, the laboratory test will determine the amount of mercury in the sample.
Antagonism (in toxicology)
Combined effect of two or more factors that is smaller than the solitary effect of any one of those factors.
Anthropogenic
Caused by or influenced by human activities
Apoptosis
Programmed cell death, the body's normal method of disposing of damaged, unwanted, or unneeded cells.
Aqueous
a. of, relating to, or resembling water <an aqueous vapor> b. made from, with, or by water <an aqueous solution>
Aqueous Solubility
The maximum concentration of a chemical that will dissolve in pure water at a reference temperature.
Aquifer
An underground geological formation, or group of formations, containing water. Are sources of groundwater for wells and springs.
ALARA
Acronym for "as low as (is) reasonably achievable." Means making every reasonable effort to maintain exposures to ionizing radiation as far below the dose limits as practical, consistent with the purpose for which the licensed activity is undertaken, taking into account the state of technology, the economics of improvements in relation to state of technology, the economics of improvements in relation to benefits to the public health and safety, and other societal and socioeconomic considerations, and in relation to utilization of nuclear energy and licensed materials in the public interest (see 10 CFR 20.1003 )
Assessment endpoint
An explicit expression of the environmental value that is to be protected, operationally defined by an ecological entity and its attributes. For example, salmon are valued ecological entities; reproduction and age class structure are some of their important attributes. Together "salmon reproduction and age class structure" form an assessment endpoint.
Asthma
Chronic respiratory disease characterized by bronchoconstriction, excessive mucus secretion and oedema of the pulmonary alveoli, resulting in difficulty in breathing out, wheezing, and cough.
B lymphocyte (B cell)
A type of lymphocyte (white blood cells), produced in the bone marrow, which synthesizes and secretes antibodies in response to the presence of a foreign substance or one identified by it as being foreign. Also called B-cell.
Background Level
1. The concentration of a substance in an environmental media (air, water, or soil) that occurs naturally or is not the result of human activities. 2. In exposure assessment the concentration of a substance in a defined control area, during a fixed period of time before, during, or after a data-gathering operation.
Bacteria
(Singular: bacterium) Microscopic living organisms. Bacteria in soil, water or air may be pathogenic and cause illnesses in humans, animals and plants. They can also be non-pathogenic and be beneficial in pollution control by metabolizing organic matter in sewage, oil spills or other pollutants.
Basal metabolic rate
The rate at which heat is given off by an organism at complete rest.
Bedrock
The solid rock underneath surface soils.
Bench-scale Tests
Laboratory testing of potential cleanup technologies (See: treatability studies .)
Beta particle
A charged particle emitted from a nucleus during radioactive decay, with a mass equal to 1/1837 that of a proton. A negatively charged beta particle is identical to an electron. A positively charged beta particle is called a positron. Large amounts of beta radiation may cause skin burns, and beta emitters are harmful if they enter the body. Beta particles may be stopped by thin sheets of metal or plastic.
Bioaccumulants
Substances that increase in concentration in various tissues of living organisms as they take in contaminated air, water, or food because the substances are very slowly metabolized or excreted. (See: biological magnification .)
Biochemical Oxygen Demand (BOD)
A measure of the amount of oxygen consumed in the biological processes that break down organic matter in water. The greater the BOD, the greater the degree of pollution.
Biocid/e n., -al adj.
Substance intended to kill living organisms.
Biohazard
An agent of biological origin that has the capacity to produce deleterious effects on humans, i.e. microorganisms, toxins, and allergens derived from those organisms; and allergens and toxins derived from higher plants and animals.
Biological Exposure Indices (BEI)
Biological Exposure Indices. A guidance value recommended by ACGIH ® for assessing biological monitoring result
Biologic monitoring
The measuring of hazardous substances in biologic materials (such as blood, hair, urine, or breath) to determine whether exposure has occurred. A blood test for lead is an example of biologic monitoring.
Biologic uptake
The transfer of substances from the environment to plants, animals, and humans.
Biomarker
A cellular or molecular indicator of exposure, health effects, or susceptibility. Biomarkers can be used to measure internal dose, biologically effective dose, early biological response, altered structure or function, suceptability.
Biomedical testing
Testing of persons to find out whether a change in a body function might have occurred because of exposure to a hazardous substance.
Bioremediation
Use of living organisms to clean up oil spills or remove other pollutants from soil, water, or wastewater; use of organisms such as non-harmful insects to remove agricultural pests or counteract diseases of trees, plants, and garden soil.
Biota
The animal and plant life of a given region
Biotechnology
The broad definition of biotechnology is simply the industrial use of living organisms (or parts of living organisms) to produce foods, drugs, or other products.
BOD5
The amount of dissolved oxygen consumed in five days by biological processes breaking down organic matter.
Body burden
Total amount of a substance, organism, or noxious agent present in an organism at a given time
Built Environment
It encompasses all buildings, spaces and products that are created, or modified, by people. It includes homes, schools, workplaces, parks/recreation areas, greenways, business areas and transportation systems. It extends overhead in the form of electric transmission lines, underground in the form of waste disposal sites and subway trains, and across the country in the form of highways. It includes land-use planning and policies that impact our communities in urban, rural and suburban areas.
Cancer risk
A theoretical risk for getting cancer if exposed to a substance every day for 70 years (a lifetime exposure). The true risk might be lower.
Carcinogen
Any substance that can cause or aggravate cancer.
Case study
An uncontrolled (prospective or retrospective) observational study involving an intervention and outcome in a single patient. (Also known as a single case report or anecdote.)
CAS Registration Number
A number assigned by the Chemical Abstract Service to identify a chemical.
Centers for Disease Control and Prevention (CDC)
Collaborates to create the expertise, information, and tools that people and communities need to protect their health - through health promotion, prevention of disease, injury and disability, and preparedness for new threats.

CDC seeks to accomplish its mission by working with partners throughout the nation and the world to

- monitor health
- detect and investigate health problems
- conduct research to enhance prevention
- develop and advocate sound public health policies
- implement prevention strategies
- promote healthy behaviors
- foster safe and healthful environments
- provide leadership and training
Certified Output Protection Protocol
A device driver technology used to enable high-bandwidth Digital Content Protection ( HDCP ) during the transmission of digital video between applications and high-definition displays. COPP is a Microsoft security technology for video systems that require a logo certification. For security drivers are authenticated and protected from tampering to prevent unauthorized high-quality recording from the video outputs. COPP control signals are also encrypted.
Chemical, Biological, Radioactive Nuclear, Explosive (CBRNE) Incidents
CBRN incidents are deliberate, malicious acts with the intention to kill or sicken and disrupt society. CBRN may be used in warfare or terrorism
Chemical Oxygen Demand (COD)
A measure of the oxygen required to oxidize all compounds, both organic and inorganic, in water.
Chronic Effect
1. An adverse effect on a human or animal resulting from long term exposure to a substance.
2. A persistent (month, years or permanent) adverse health effect resulting from a short term (acute) exposure
Chronic Exposure
Multiple exposures occurring over an extended period of time or over a significant fraction of an animal's or human's lifetime (Usually seven years to a lifetime.)
Chronic Obstructive Pulmonary Disease
Chronic obstructive pulmonary disease (COPD) is a lung disease characterized by chronic obstruction of lung airflow that interferes with normal breathing and is not fully reversible. The more familiar terms 'chronic bronchitis' and 'emphysema' are no longer used, but are now included within the COPD diagnosis. COPD is not simply a "smoker's cough" but an under-diagnosed, life-threatening lung disease.
Cluster investigation
A review of an unusual number, real or perceived, of health events (for example, reports of cancer) grouped together in time and location. Cluster investigations are designed to confirm case reports; determine whether they represent an unusual disease occurrence; and, if possible, explore possible causes and contributing environmental factors.
Cohort study
An epidemiological method of identifying two groups (cohorts) of individuals, one which has received the exposure of interest and one which has not, and following both groups forward for the outcome of interest.
Command and control
Standards are usually tailor-made to regulate how a specific activity or class of activities need to be carried out. Compliance monitoring and eventual sanctioning of trespasses are usually indispensable features of effective C&C. The primary disadvantages of the C&C approach are that it is overly constraining, leaves little room for flexibility, is not adaptable on a case-by-case basis and tends to retard technological change. Moreover, regulations underlying the C&C approach offer no incentive for producers to attain standards higher than those imposed by the law. While C&C is often criticized for these reasons, it is widely used by government agencies and even sometimes requested by the industry. Producing regulations is done within the logic of public administration, often regardless of their enforceability. In terms of political relations, "something has been done", and since the same norm or standard applies to everybody, it provides a sense of fairness. The frequent weakness of results monitoring and accountability, in the political arena, however, often leaves implementation in the shadow.
Community Assistance Panel (CAP)
A group of people from a community and from health and environmental agencies who work with ATSDR to resolve issues and problems related to hazardous substances in the community. CAP members work with ATSDR to gather and review community health concerns, provide information on how people might have been or might now be exposed to hazardous substances, and inform ATSDR on ways to involve the community in its activities.
Comparison value (CV)
Calculated concentration of a substance in air, water, food, or soil that is unlikely to cause harmful (adverse) health effects in exposed people. The CV is used as a screening level during the public health assessment process. Substances found in amounts greater than their CVs might be selected for further evaluation in the public health assessment process.
Composite Sample
1. Composite sampling is a technique whereby multiple temporally or spatially discrete, media or tissue samples are combined, thoroughly homogenized, and treated as a single sample. An example would be a series of water samples taken over a given period of time and weighted by flow rate.
Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA)
CERCLA, also known as Superfund, is the federal law that concerns the removal or cleanup of hazardous substances in the environment and at hazardous waste sites. ATSDR, which was created by CERCLA, is responsible for assessing health issues and supporting public health activities related to hazardous waste sites or other environmental releases of hazardous substances. This law was later amended by the Superfund Amendments and Reauthorization Act (SARA) .
Concentration
The relative amount of a substance within another substance. An example is five ppm of carbon monoxide in air or 1 mg/l of iron in water.
Consumer Product Safety Commission (CPSC)
The U.S. Consumer Product Safety Commission is charged with protecting the public from unreasonable risks of serious injury or death from more than 15,000 types of consumer products. Deaths, injuries and property damage from consumer product incidents cost the nation more than $800 billion annually. The CPSC is committed to protecting consumers and families from products that pose a fire, electrical, chemical, or mechanical hazard or can injure children. The CPSC's work to ensure the safety of consumer products - such as toys, cribs, power tools, cigarette lighters, and household chemicals - contributed significantly to the 30 percent decline in the rate of deaths and injuries associated with consumer products over the past 30 years.
Criteria Pollutants
The 1970 amendments to the Clean Air Act required EPA to set National Ambient Air Quality Standards for certain pollutants known to be hazardous to human health. EPA has identified and set standards to protect human health and welfare for six pollutants: ozone, carbon monoxide, total suspended particulates, sulfur dioxide, lead, and nitrogen oxide. The term, "criteria pollutants" derives from the requirement that EPA must describe the characteristics and potential health and welfare effects of these pollutants. It is on the basis of these criteria that standards are set or revised.
Cryptosporidium
A protozoan microbe associated with the disease cryptosporidiosis in man. The disease can be transmitted through ingestion of drinking water, person-to-person contact, or other pathways, and can cause acute diarrhea, abdominal pain, vomiting, fever, and can be fatal as it was in the 1993 Milwaukee episode.
Curie (Ci)
The basic unit used to describe the intensity of radioactivity in a sample of material. The curie is equal to 37 billion (3.7 x 10 10 ) disintegrations per second, which is approximately the activity of 1 gram of radium. A curie is also a quantity of any radionuclide that decays at a rate of 37 billion disintegrations per second. It is named for Marie and Pierre Curie, who discovered radium in 1898. 37 billion (3.7 x 10 10 ) becquerels = 1 curie (Ci).
Cytokine
Any of a group of soluble proteins that are released by a cell causing a change in function or development of the same cell (autocrine), an adjacent cell (paracrine), or a distant cell (endocrine); cytokines are involved in reproduction, growth and development, normal homeostatic regulation, response to injury and repair, blood clotting, and host resistance (immunity and tolerance).
Delayed health effect
A disease or an injury that happens as a result of exposures that might have occurred in the past.
Dermal Absorption/Penetration
Process by which a chemical penetrates the skin and enters the body as an internal dose.
Dermal Exposure
Contact between a chemical and the skin.
Dermal Toxicity
The ability of a pesticide or toxic chemical to poison people or animals by contact with the skin. (See: contact pesticide.)
Descriptive epidemiology
Study of the occurrence of disease or other health -related characteristics in populations, including general observations concerning the relationship of disease to basic characteristics such as age, sex, race, occupation, and social class; it may also be concerned with geographic location. The major characteristics in descriptive epidemiology can be classified under the headings: individuals, time and place
Detection Limit
The lowest concentration of a chemical that can reliably be distinguished from a zero concentration.
Disease registry
A system of ongoing registration of all cases of a particular disease or health condition in a defined population.
Disease Vector
A phrase used in parasitology and entomology to describe a special type of intermediate host for parasites. A vector is not only required as part of the parasite's development, but it also delivers the parasite directly to subsequent hosts, avoiding free living stages such as those observed in Schistosoma which infects snails before having a brief free living stage that actively infects their next host.
Disinfectant
A chemical or physical process that kills or prevent the growth of bacteria and other micro- organisms in water, air, or on surfaces. Chlorine is often used to disinfect sewage treatment effluent, water supplies, wells, and swimming pools.
Disinfectant By-Product
A compound formed by the reaction of a disinfenctant such as chlorine with organic material in the water supply; a chemical byproduct of the disinfection process
DNA Repair
As a major defense against environmental damage to cells DNA repair is present in all organisms examined including bacteria, yeast, drosophila, fish, amphibians, rodents and humans. DNA repair is involved in processes that minimize cell killling, mutations, replication errors, persistence of DNA damage and genomic instability. Abnormalities in these processes have been implicated in cancer and aging.
Dosage/Dose
1. The actual quantity of a chemical administered to an organism or to which it is exposed.
2. The amount of a substance that reaches a specific tissue (e.g. the liver).
3. The amount of a substance available for interaction with metabolic processes after crossing the outer boundary of an organism. (See: absorbed dose, administered dose, applied dose, potential dose.)
Dose-Response Relationship
The quantitative relationship between the amount of exposure to a substance and the extent of toxic injury or disease produced.
Ecological Risk Assessment
The application of a formal framework, analytical process, or model to estimate the effects of human actions(s) on a natural resource and to interpret the significance of those effects in light of the uncertainties identified in each component of the assessment process. Such analysis includes initial hazard identification, exposure and dose-response assessments, and risk characterization.
Economic Incentives
Incentives are a different approach. The idea of incentives is not to strictly forbid/allow, but rather to provide signals on public objectives while leaving some room for individual and collective decision-making to respond to them. Incentives play indirectly through the determinants of individual/collective choices, such as the profit motive or normative values. Market or social forces can be very efficient vectors to force the global outcome of individual actions towards collectively set objectives. Different kinds of incentives can be developed in isolation or in combination:

- improving the institutional framework (definition of rights and participatory processes)
- developing collective values (education, information, training)
- creating nonmarket economic incentives (taxes and subsidies)
- establishing market incentives (tradable property/access rights; eco-labelling)
ED50
The dose of a drug that is pharmacologically effective for 50% of the population exposed to the drug or a 50% response in a biological system that is exposed to the drug.
Emergency Planning and Community Right-to-Know Act (EPCRA)
Emergency Planning and Community Right-to-Know Act (EPCRA) establishes requirements for Federal, state and local governments, Indian Tribes, and industry regarding emergency planning and "Community Right-to-Know" reporting on hazardous and toxic chemicals. The Community Right-to-Know provisions help increase the public's knowledge and access to information on chemicals at individual facilities, their uses, and releases into the environment. States and communities, working with facilities, can use the information to improve chemical safety and protect public health and the environment. EPCRA was passed in response to concerns regarding the environmental and safety hazards posed by the storage and handling of toxic chemicals. These concerns were triggered by the disaster in Bhopal, India, in which more than 2,000 people suffered death or serious injury from the accidental release of methyl isocyanate. To reduce the likelihood of such a disaster in the United States, Congress imposed requirements on both states and regulated facilities.
Emission
Pollution discharged into the atmosphere from smokestacks, other vents, and surface areas of commercial or industrial facilities; from residential chimneys; and from motor vehicle, locomotive, or aircraft exhausts.
Endocrine disruptor
Exogenous chemical that alters function(s) of the endocrine system and consequently causes adverse health effects in an intact organism, its progeny or (sub) populations.
Environmental Equity/Justice
Equal protection from environmental hazards for individuals, groups, or communities regardless of race, ethnicity, or economic status. This applies to the development, implementation, and enforcement of environmental laws, regulations, and policies, and implies that no population of people should be forced to shoulder a disproportionate share of negative environmental impacts of pollution or environmental hazard due to a lack of political or economic strength levels.
Environmental media
Soil, water, air, biota (plants and animals), or any other parts of the environment that can contain contaminants.
Environmental media and transport mechanism
Environmental media include water, air, soil, and biota (plants and animals). Transport mechanisms move contaminants from the source to points where human exposure can occur. The environmental media and transport mechanism is the second part of an exposure pathway
Ergonomics
Ergonomics is the study of human characteristics for the appropriate design of the living and working environment. Ergonomic researchers strive to learn about human characteristics (capabilities, limitations, motivations, and desires) so that this knowledge can be used to adapt a human-made environment to the people involved. There are three levels of ergonomic knowledge utilization: tolerable, acceptable, and optimal.
Estrogen
Any of various natural steroids (as estradiol) that are formed from androgen precursors, that are secreted chiefly by the ovaries, placenta, adipose tissue, and testes, and that stimulate the development of female secondary sex characteristics and promote the growth and maintenance of the female reproductive system.
Eutrophication
The slow aging process during which a lake, estuary, or bay evolves into a bog or marsh and eventually disappears. During the later stages of eutrophication the water body is choked by abundant plant life due to higher levels of nutritive compounds such as nitrogen and phosphorus. Human activities can accelerate the process.
Exposure Assessment
Identifying the pathways by which toxicants may reach individuals, estimating how much of a chemical an individual is likely to be exposed to, and estimating the number likely to be exposed.
Exposure-dose reconstruction
A method of estimating the amount of people's past exposure to hazardous substances. Computer and approximation methods are used when past information is limited, not available, or missing.
Exposure investigation
The collection and analysis of site-specific information and biologic tests (when appropriate) to determine whether people have been exposed to hazardous substances.
Exposure pathway
The route a substance takes from its source (where it began) to its end point, and how people get exposed to it. An exposure pathway has five parts: a source of contamination (such as an abandoned business); an environmental media and transport mechanism (such as movement through groundwater); a point of exposure (such as a private well); a route of exposure (eating, drinking, breathing, or touching), and a receptor population (people potentially or actually exposed). When all five parts are present, the exposure pathway is termed a completed exposure pathway.
Feasibility Study
1. Analysis of the practicability of a proposal; e.g., a description and analysis of potential cleanup alternatives for a site such as one on the National Priorities List. The feasibility study usually recommends selection of a cost-effective alternative. It usually starts as soon as the remedial investigation is underway; together, they are commonly referred to as the "RI/FS".

2. A small-scale investigation of a problem to ascertain whether a proposed research approach is likely to provide useful data.
Exposure Point
A location of potential contact between an organism and a chemical or physical agent.
Exposure registry
A system of ongoing follow-up of people who have had documented environmental exposures.
Exposure-Response relationship
the connection between the amount of a chemical administered and a specific toxic effect in the organism, also called the dose-response relationship
Gamma radiation
High-energy, short wavelength, electromagnetic radiation emitted from the nucleus. Gamma radiation frequently accompanies alpha and beta emissions and always accompanies fission. Gamma rays are very penetrating and are best stopped or shielded by dense materials, such as lead or depleted uranium. Gamma rays are similar to x-rays.
Gas phase
The simplest chemical reactions are those that occur in the gas phase in a single step, such as the transfer of a chlorine atom from ClNO 2 to NO to form NO₂ and ClNO.

ClNO₂ ( g ) + NO( g ) ↔ NO₂ ( g ) + ClNO( g )

This reaction can be understood by writing the Lewis structures for all four components of the reaction. Both NO and NO₂ contain an odd number of electrons. Both NO and NO₂ can therefore combine with a neutral chlorine atom to form a molecule in which all of the electrons are paired. This reaction therefore involves the transfer of a chlorine atom from one molecule to another, as shown in the figure below.
Geographic Information System (GIS)
A computer system designed for storing, manipulating, analyzing, and displaying data in a geographic context.
Gene
Structurally a basic unit of hereditary material; an ordered sequence of nucleotide bases that encodes one polypeptide chain (following transcription to mRNA).
SN cistron.
Global Warming
An increase in the near surface temperature of the Earth. Global warming has occurred in the distant past as the result of natural influences, but the term is most often used to refer to the warming predicted to occur as a result of increased emissions of greenhouse gases. Scientists generally agree that the Earth's surface has warmed by about 1 degree Fahrenheit in the past 140 years. The Intergovernmental Panel on Climate Change (IPCC) recently concluded that increased concentrations of greenhouse gases are causing an increase in the Earth's surface temperature and that increased concentrations of sulfate aerosols have led to relative cooling in some regions, generally over and downwind of heavily industrialized areas.
Gradient
Change in the value of a quantity (as temperature, pressure, or concentration) with change in a given variable and especially per unit on a linear scale.
Gray (Gy)
The international system (SI) unit of absorbed dose. One gray is equal to an absorbed dose of 1 Joule/kilogram (one gray equals 100 rads).
Ground Water
The supply of fresh water found beneath the Earth's surface, usually in aquifers, which supply wells and springs. Because ground water is a major source of drinking water, there is growing concern over contamination from leaching agricultural or industrial pollutants or leaking underground storage tanks.
Hazard Analysis and Critical Control Points
HACCP is a production control system for the food industry. It is a process that identifies where potential contamination can occur (the critical control points or CCPs) and strictly manages and monitors these points as a way of ensuring the process is in control and th
Half-Life
1. The time required for half the atoms in a sample to decay, or a pollutant to lose one-half of its original concentration, for example, the biochemical half-life of DDT in the environment is 15 years.
2. The time required for half of the atoms of a radioactive element to undergo self-transmutation or decay (half-life of radium is 1620 years).
3. The time required for the elimination of half a total dose from the body.
Hazard
1. Potential for radiation, a chemical or other pollutant to cause human illness or injury.
2. In the pesticide program, the inherent toxicity of a compound. Hazard identification of a given substances is an informed judgment based on verifiable toxicity data from animal models or human studies.
Hazardous Substance
1. Any material that poses a threat to human health and/or the environment. Typical hazardous substances are toxic, corrosive, ignitable, explosive, or chemically reactive.
2. Any substance designated by EPA to be reported if a designated quantity of the substance is spilled in the waters of the United States or is otherwise released into the environment.
Hazardous Substance Release and Health Effects Database (HazDat)
The scientific and administrative database system developed by ATSDR to manage data collection, retrieval, and analysis of site-specific information on hazardous substances, community health concerns, and public health activities.
Hazardous Waste
By-products of society that can pose a substantial or potential hazard to human health or the environment when improperly managed. Possesses at least one of four characteristics (ignitability, corrosivity, reactivity, or toxicity), or appears on special EPA lists.
Health Assessment
Public health assessments challenge ATSDR to integrate environmental sampling data, health outcome data, and community concerns successfully in the evaluation of the health implications of hazardous substances released to the environment. Doing so enables ATSDR staff members to make the difficult decisions as to why, where, and for whom public health actions should be undertaken.
Health Consultation
A review of available information or collection of new data to respond to a specific health question or request for information about a potential environmental hazard. Health consultations are focused on a specific exposure issue. Health consultations are therefore more limited than a public health assessment, which reviews the exposure potential of each pathway and chemical [compare with public health assessment ].
Health effects studies related to contaminants
a combination of procedures, methods and tools bywhich a policy, program or project may be judged as to its potential effects on thehealth of a population, and the distribution of those effects within the population.
Health investigation
The collection and evaluation of information about the health of community residents. This information is used to describe or count the occurrence of a disease, symptom, or clinical measure and to evaluate the possible association between the occurrence and exposure to hazardous substances.
Health Registry
The Agency for Toxic Substances and Disease Registry (ATSDR) , based in Atlanta, Georgia, is a federal public health agency of the U.S. Department of Health and Human Services . ATSDR serves the public by using the best science, taking responsive public health actions, and providing trusted health information to prevent harmful exposures and diseases related to toxic substances.
Health Statistics Review
The analysis of existing health information (i.e., from death certificates, birth defects registries, and cancer registries) to determine if there is excess disease in a specific population, geographic area, and time period. A health statistics review is a descriptive epidemiologic study.)
Heavy Metals
Metallic elements with high atomic weights; (e.g. mercury, chromium, cadmium, arsenic, and lead); can damage living things at low concentrations and tend to accumulate in the food chain.
Helminths
A group of parasites commonly referred to as worms. The group includes trematodes, cestodes, and nematodes.

Schistosomes are trematodes; the species that most commonly infect humans are: Schistosoma haematobium, S. intercalatum, S. japonicum, S. mansoni, and S.mekongi.

Cestodes include the beef and pork tapeworms, the largest of the helminths, and nematodes include the roundworm Ascaris lumbri-coides, the whipworm Trichuris trichiura, and the hookworms Necator americanus and Ancylostoma duodenale; these nematodes are collectively referred to as soil-transmitted helminths (STH).
Herbicide
Substance intended to kill plants.
HGPRT
Hypoxanthine-guanine phosphoribosyltransferase ( HGPRT ) is an enzyme in purine metabolism . The enzyme primarily functions to salvage purines from degraded DNA to renewed purine synthesis. In this role, it acts as a catalyst in the reaction between guanine and phosphoribosyl pyrophosphate (PRPP) to form GMP
Incineration
A treatment technology involving destruction of waste by controlled burning at high temperatures; e.g., burning sludge to remove the water and reduce the remaining residues to a safe, non-burnable ash that can be disposed of safely on land, in some waters, or in underground locations.
Indeterminate public health hazard
The category used in ATSDR's public health assessment documents when a professional judgment about the level of health hazard cannot be made because information critical to such a decision is lacking.
Industrial Hygiene
Industrial hygiene is the science of anticipating, recognizing, evaluating, and controlling workplace conditions that may cause workers' injury or illness. Industrial hygienists use environmental monitoring and analytical methods to detect the extent of worker exposure and employ engineering, work practice controls, and other methods to control potential health hazards.
Ingestion
The act of swallowing something through eating, drinking, or mouthing objects. A hazardous substance can enter the body this way [see route of exposure].
Infection control
Infection control refers to all policies, procedures and activities, which aim to prevent or minimize the risk of transmission of infectious diseases. This refers to health care acquired infections (HAI) as well as to infections of public health concern, making it a crosscutting, multidisciplinary activity
Infectious Diseases
Infectious diseases are caused by pathogenic microorganisms, such as bacteria, viruses, parasites or fungi; the diseases can be spread, directly or indirectly, from one person to another. Zoonotic diseases are infectious diseases of animals that can cause disease when transmitted to humans
Inhalation
The act of breathing. A hazardous substance can enter the body this way [see route of exposure]
Injury Prevention
A combination of research, development of data collection systems, the introduction of specific prevention measures such as improvements in the local environment, legislation, public education, product safety, and improvements in the level and quality of emergency care
Inorganic Chemicals
Chemical substances of mineral origin, not of basically carbon structure.
Institute of Medicine (IOM)
The IOM was established in 1970 and chartered under the National Academy of Sciences. IOM provides independent, objective, evidence-based advice to policy makers, health professionals, the private sector and the public. The mission of the IOM is to embrace the health of people everywhere.
Intermediate duration exposure
Contact with a substance that occurs for more than 14 days and less than a year [compare with acute exposure and chronic exposure ]
International Agency for Research on Cancer
IARC's mission is to coordinate and conduct research on the causes of human cancer, the mechanisms of carcinogenesis, and to develop scientific strategies for cancer control. The Agency is involved in both epidemiological and laboratory research and disseminates scientific information through publications, meetings, courses, and fellowships.
In vitro
In glass, referring to a study in the laboratory usually involving isolated organ, tissue, cell, or biochemical systems
In vivo
In the living body, referring to a study performed on a living organism
Ionizing radiation
Any radiation capable of displacing electrons from atoms or molecules, thereby producing ions. Some examples are alpha, beta, gamma, x-rays, neutrons, and ultraviolet light. High doses of ionizing radiation may produce severe skin or tissue damage.
Inversion
A layer of warm air that prevents the rise of cooling air and traps pollutants beneath it; can cause an air pollution episode.
Ionizing Radiation
Radiation that can strip electrons from atoms; e.g. alpha, beta, and gamma radiation
IRIS
EPA's Integrated Risk Information System, an electronic data base containing the Agency's latest descriptive and quantitative regulatory information on chemical constituents. The information in IRIS is intended for those without extensive training in toxicology, but with some knowledge of health sciences.
Landfills
1. Sanitary landfills are disposal sites for non-hazardous solid wastes spread in layers, compacted to the smallest practical volume, and covered by material applied at the end of each operating day

2. Secure chemical landfills are disposal sites for hazardous waste, selected and designed to minimize the chance of release of hazardous substances into the environment
Latency
Time from the first exposure of a chemical until the appearance of a toxic effect.
LD 50/ Lethal Dose
The dose of a toxicant or microbe that will kill 50 percent of the test organisms within a designated period. The lower the LD 50, the more toxic the compound
Leaching
The process by which soluble constituents are dissolved and filtered through the soil by a percolating fluid. (See: leachate.)
Leachate
Water that collects contaminants as it trickles through wastes, pesticides or fertilizers. Leaching may occur in farming areas, feedlots, and landfills, and may result in hazardous substances entering surface water, ground water, or soil.
Life Cycle management
Every activity that a business performs has an impact - on a social, economic and environmental level. Often these impacts are not obvious or immediate, there are many that are hidden or indirect, that only appear when you take a more holistic view - essentially, when you take a step back and examine the complete life cycle of your products and services . A life cycle is made up of all the activities that go into making, selling, using, transporting and disposing of a product or service - from initial design, right through the supply chain
Lipophilic
Having an affinity for fat and high lipid solubility: a physicochemical property which describes a partitioning equilibrium of solute molecules between water and an immiscible organic solvent, favoring the latter, and which correlates with bioaccumulation.

Related bioaccumulation , bioaccumulation factor, bioconcentration , octanol-water partition coefficient .
Synonyms; hydrophobicity .
Antonyms; hydrophilicity , lipophobicity .
Local Emergency Planning Committee (LEPC)
A committee appointed by the state emergency response commission, as required by SARA Title III, to formulate a comprehensive emergency plan for its jurisdiction.
Lowest-observed-adverse-effect level (LOAEL)
Lowest concentration or amount of a substance ( dose ), found by experiment or observation, which causes an adverse effect on morphology, functional capacity, growth, development, or life span of a target organism distinguishable from normal (control) organisms of the same species and strain under defined conditions of exposure
Lymphocyte
Animal white blood cell (as opposed to red blood cell) that interacts with a foreign substance or organism, or one which it identifies as foreign, and initiates an immune response against the substance or organism. There are two groups of lymphocytes, B lymphocytes and T lymphocytes
NT B lymphocyte , immune response , T lymphocyte
Macrophage
Large (10-20 mm diameter) amoeboid and phagocytic cell found in many tissues, especially in areas of inflammation; macrophages are derived from blood monocytes and play an important role in host defense mechanisms.
Malaria
A mosquito-borne disease caused by a parasite. People with malaria often experience fever, chills, and flu-like illness. Left untreated, they may develop severe complications and die. Each year 350-500 million cases of malaria occur worldwide, and over one million people die, most of them young children in sub-Saharan Africa. This sometimes fatal disease can be prevented and cured. Bednets, insecticides, and antimalarial drugs are effective tools to fight malaria in areas where it is transmitted. Travelers to a malaria-risk area should avoid mosquito bites and take a preventive antimalarial drug.
Material Safety Data Sheet (MSDS)
A compilation of information required under the OSHA Communication Standard on the identity of hazardous chemicals, health, and physical hazards, exposure limits, and precautions. Section 311 of SARA requires facilities to submit MSDSs under certain circumstances.
Maximum Contaminant Level
The maximum permissible level of a contaminant in water delivered to any user of a public system. MCLs are enforceable standards.
Measure of effect (measurement endpoint)
A change in an attribute of an assessment endpoint or its surrogate in response to a stressor to which it is exposed.
Medical Monitoring
an automated medical device that senses a patient's vital signs and displays the results. In critical care units of hospitals it allows continuous supervision of a patient without continuous attendance thus improving patient care
Medical Waste
Any solid waste generated in the diagnosis, treatment, or immunization of human beings or animals, in research pertaining thereto, or in the production or testing of biologicals, excluding hazardous waste identified or listed under 40 CFR Part 261 or any household waste as defined in 40 CFR Sub-section 261.4 (b)(1)
Mesothelioma
Malignant tumor of the mesothelium of the pleura, pericardium or peritoneum, that may be caused by exposure to asbestos fibers and some other fibers
BT tumour
RT malignant
Metabolism
The conversion or breakdown of a substance from one form to another by a living organism
Metabolites
Any substances produced by biological processes, such as those from pesticides
Metabolomics
The use of genomic information to facilitate studies of metabolic processes.
Migration
Moving from one location to another.
Minimal Risk Level (MRL)
An MRL is an estimate of the daily human exposure to a hazardous substance that is likely to be without appreciable risk of adverse noncancer health effects over a specified duration of exposure. These substance specific estimates, which are intended to serve as screening levels, are used by ATSDR health assessors and other responders to identify contaminants and potential health effects that may be of concern at hazardous waste sites.
Missense mutations
A single base pair substitution that results in the translation of a different amino acid at that position
Mold
include all species of microscopic fungi that grow in the form of multicellular filaments, called hyphae . [1] In contrast, microscopic fungi that grow as single cells are called yeasts . A connected network of these tubular branching hyphae has multiple, genetically identical nuclei and is considered a single organism, referred to as a colony or in more technical terms a mycelium
MRSA
M ethicillin- r esistant S taphylococcus a ureus : any of several bacterial strains of the genus Staphylococcus ( S. aureus ) that are resistant to beta-lactam antibiotics (as methicillin and nafcillin, amoxicillin, and penicillin. ) and that are typically benign colonizers of the skin and mucous membranes (as of the nostrils) but may cause severe infections (as by entrance through a surgical wound) especially in immunocompromised individuals.
Mutagen/Mutagenicity
An agent that causes a permanent genetic change in a cell other than that which occurs during normal growth. Mutagenicity is the capacity of a chemical or physical agent to cause such permanent changes.
Nanoscale
Materials and structures range from 1-100 nanometers. They can have different properties at the nanoscale.
Nanotechnology
Research and technology development at the atomic, molecular or macromolecular levels, in the length scale of approximately 1 - 100 nanometer range, to provide a fundamental understanding of phenomena and materials at the nanoscale and to create and use structures, devices and systems that have novel properties and functions because of their small and/or intermediate size. The novel and differentiating properties and functions are developed at a critical length scale of matter typically under 100 nm.
National Academy of Science
The National Academy of Sciences (NAS) is an honorific society of distinguished scholars engaged in scientific and engineering research, dedicated to the furtherance of science and technology and to their use for the general welfare.
National Ambient Air Quality Standards (NAAQS)
Standards established by EPA that apply for outdoor air throughout the country. (See: criteria pollutants , state implementation plans , emissions trading .)
National Institutes of Health
The National Institutes of Health (NIH), a part of the U.S. Department of Health and Human Services , is the primary Federal agency for conducting and supporting medical research.
National Institute for Occupational Safety and Health (NIOSH)
The National Institute for Occupational Safety and Health (NIOSH) is the federal agency responsible for conducting research and making recommendations for the prevention of work-related injury and illness. NIOSH is part of the Centers for Disease Control and Prevention (CDC) in the Department of Health and Human Services .
National Priorities List (NPL)
EPA's list of the most serious uncontrolled or abandoned hazardous waste sites identified for possible long-term remedial action under Superfund. The list is based primarily on the score a site receives from the Hazard Ranking System. EPA is required to update the NPL at least once a year. A site must be on the NPL to receive money from the Trust Fund for remedial action.
National Research Council
The mission of the NRC is to improve government decision making and public policy, increase public education and understanding, and promote the acquisition and dissemination of knowledge in matters involving science, engineering, technology, and health.
National Toxicology Program (NTP)
The NTP is an interagency program, within the Department of Health and Human Services, whose mission is to evaluate agents of public health concern by developing and applying tools of modern toxicology and molecular biology. The program maintains an objective, science-based approach in dealing with critical issues in toxicology and is committed to using the best science available to prioritize, design, conduct, and interpret its studies. To that end, the NTP is continually evolving to remain at the cutting edge of scientific research and to develop and apply new technologies.
Natural attenuation
Reliance on natural attenuation processes (within the context of a carefully controlled and monitored site cleanup approach) to achieve site-specific remediation objectives within a time frame that is reasonable compared to that offered by other more active methods. The 'natural attenuation processes' that are at work in such a remediation approach include a variety of physical, chemical, or biological processes that, under favorable conditions, act without human intervention to reduce the mass, toxicity, mobility, volume, or concentration of contaminants in soil or groundwater. These in-situ processes include biodegradation; dispersion; dilution; sorption; volatilization; radioactive decay; and chemical or biological stabilization, transformation, or destruction of contaminants." ( EPA, OSWER Directive 9200.4-17P )
No apparent public health hazard
A category used in ATSDR's public health assessments for sites where human exposure to contaminated media might be occurring, might have occurred in the past, or might occur in the future, but where the exposure is not expected to cause any harmful health effects.
Noise-induced hearing loss
Irreversible hearing loss caused by exposure to very loud impulse sounds, such as an explosion, or to less-intense sounds for an extended period of time. Loud noise levels damage hair cells of the inner ear.
Non-ionizing Electromagnetic Radiation
1. Radiation that does not change the structure of atoms but does heat tissue and may cause harmful biological effects.
2. Microwaves, radio waves, and low-frequency electromagnetic fields from high-voltage transmission lines.
No Observable Adverse Effect Level (NOAEL)
An exposure level at which there are no statistically or biologically significant increases in the frequency or severity of adverse effects between the exposed population and its appropriate control; some effects may be produced at this level, but they are not considered as adverse, or as precursors to adverse effects. In an experiment with several NOAELs, the regulatory focus is primarily on the highest one, leading to the common usage of the term NOAEL as the highest exposure without adverse effects.
No public health hazard
A category used in ATSDR's public health assessment documents for sites where people have never and will never come into contact with harmful amounts of site-related substances.
Not in my Back Yard (NIMBY)
Not in My Backyard thoroughly analyzes the issues and documents the problems that make enforcement of environmental justice almost nonexistent. Executive Order 12,898, which created a right to environmental justice, has yet to be fully realized or enforced. As a result of judicial decisions limiting the ability of individuals to file disparate impact cases under § 602 of Title VI and § 1983 of the Civil Rights Act, communities have been forced to rely even more on what should be but often is not—vigorous agency enforcement to remedy environmental justice complaints.
Odor Threshold
The minimum odor of a water or air sample that can just be detected after successive dilutions with odorless water. Also called threshold odor.
Organophosphates
Pesticides that contain phosphorus, some of which are used in fertilizers and pesticides, are short-lived, but some can be toxic when first applied.
Occupational Safety and Health Administration (OSHA)
OSHA's mission is to assure the safety and health of America's workers by setting and enforcing standards; providing training, outreach, and education; establishing partnerships; and encouraging continual improvement in workplace safety and health.
Particulates
1. Fine liquid or solid particles such as dust, smoke, mist, fumes, or smog, found in air or emissions
2. Very small solids suspended in water; they can vary in size, shape, density and electrical charge and can be gathered together by coagulation and flocculation.
Parts Per Billion (ppb)/Parts Per Million (ppm)
Units commonly used to express contamination ratios, as in establishing the maximum permissible amount of a contaminant in water, land, or air.
Permeability
The rate at which liquids pass through soil or other materials in a specified direction.
Permissible Exposure Limit
Also referred to as PEL, federal limits for workplace exposure to contaminants as established by OSHA.
Persistence
Refers to the length of time a compound stays in the environment, once introduced. A compound may persist for less than a second or indefinitely.
Persistent Organic Pollutants (POPs)
POPs are a set of chemicals that are toxic, persist in the environment for long periods of time, and biomagnify as they move up through the food chain. POPs have been linked to adverse effects on human health and animals, such as cancer, damage to the nervous system, reproductive disorders, and disruption of the immune system. Because they circulate globally via the atmosphere, oceans, and other pathways, POPs released in one part of the world can travel to regions far from their source of origin.
Pesticide
Substances or mixture intended for preventing, destroying, repelling, or mitigating any pest. Also, any substance or mixture intended for use as a plant regulator, defoliant, or desiccant.
Physiologically based pharmacokinetic model (PBPK model)
A computer model that describes what happens to a chemical in the body. This model describes how the chemical gets into the body, where it goes in the body, how it is changed by the body, and how it leaves the body.
Plume
1. A visible or measurable discharge of a contaminant from a given point of origin. Can be visible or thermal in water, or visible in the air as, for example, a plume of smoke.
2 The area of radiation leaking from a damaged reactor.
3. Area downwind within which a release could be dangerous for those exposed to leaking fumes.
PM-10/PM-2.5
PM-10 is a measure of particles in the atmosphere that are less than 10 micrometers in diameter that include both fine and coarse dust particles. These particles pose the greatest health concern because they can pass through the nose and throat and get into the lungs. PM-2.5 is a measure of smaller particles in the air. The particle mix in most U.S. cities is dominated by fine particles (less than 2.5 micrometers in diameter) generated by combustion sources, with smaller amounts of coarse dust (between 2.5 and 10 micrometers in diameter).PM-10 has been the pollutant particulate level standard against which EPA has been measuring Clean Air Act compliance. On the basis of newer scientific findings, the Agency is considering regulations that will make PM-2.5 the new "standard".
Point of exposure
The place where someone can come into contact with a substance present in the environment [see exposure pathway].
Polarity
In electricity, the quality of having two oppositely charged poles, one positive and one negative.
Polluter-pays principle
Office of Site Remediation Enforcement manages the enforcement of EPA's national hazardous waste cleanup programs: Superfund (officially known as the Comprehensive Environmental Response, Compensation and Liability Act), the Resource Conservation and Recovery Act (RCRA), the Oil Pollution Act (OPA), and underground storage tanks (UST). OSRE support and provide the means for the regions and states to vigorously and effectively enforce these statutes. OSRE goals are to achieve prompt site cleanup and maximum liable party participation in performing and paying for cleanup in ways which promote environmental justice and fairness.
Population
A group of interbreeding organisms occupying a particular space; the number of humans or other living creatures in a designated area.
Potable Water
Water that is safe for drinking and cooking.
Potentially Responsible Party (PRP)
Any individual or company--including owners, operators, transporters or generators--potentially responsible for, or contributing to a spill or other contamination at a Superfund site. Whenever possible, through administrative and legal actions, EPA requires PRPs to clean up hazardous sites they have contaminated.
Precautionary Principle
When information about potential risks is incomplete, basing decisions about the best ways to manage or reduce risks on a preference for avoiding unnecessary health risks instead of on unnecessary economic expenditures.
Preliminary Assessment
An assessment of information about a site and its surrounding area. A Preliminary Assessment is designed to determine whether a sites poses little or no threat to human health and the environment or if it does pose a threat, whether the threat requires further investigation. PA investigations collect readily available information about a site and its surrounding area. The PA is designed to distinguish, based on limited data, between sites that pose little or no threat to human health and the environment and sites that may pose a threat and require further investigation. The PA also identifies sites requiring assessment for possible emergency response actions. If the PA results in a recommendation for further investigation, a Site Inspection is performed.
Prevalence
The number of existing disease cases in a defined population during a specific time period [contrast with incidence ]. When used without qualification, the term usually refers to the situation at a specified point in time (point prevalence). Note that this is a number not a rate.
Prevalence survey
The measure of the current level of disease(s) or symptoms and exposures through a questionnaire that collects self-reported information from a defined population
Prevention
Actions that reduce exposure or other risks, keep people from getting sick, or keep disease from getting worse.
Probability
Chance (a measure of how likely it is that some event will occur; a number expressing the ratio of favorable cases to the whole number of cases possible) "the probability that an unbiased coin will fall with the head up is 0.5"
Promoter
A chemical believed to promote carcinogenicity or mutagenicity
Proteomics
The term 'proteome' was first used in 1994 to refer to all the proteins in a cell, tissue, or organism. Proteomics refers to the study of the proteome. Because proteins are involved in almost all biological activities, including disease, the proteome is a critical target for understanding how disease arises and how to prevent it.

Protein scientists pursue many avenues of inquiry about proteins, working to determine their function and amino acid sequence; their three-dimensional structure; how the addition of sugars, phosphates, or fats affects protein function; and how proteins interact with other molecules, including other proteins. Some researchers focus on the proteins present in particular parts of the cell such as the outer cell membrane, the nucleus, the cytoplasm (the region of the cell outside the nucleus), or the nuclear membrane; others analyze protein-protein interactions in a particular cell or organism; some study the differences between the proteins present in diseased vs. healthy cells.
Protocol
A series of formal steps for conducting a test.
Protozoa
One-celled animals that are larger and more complex than bacteria. May cause disease.
Public availability session
An informal, drop-by meeting at which community members can meet one-on-one with ATSDR staff members to discuss health and site-related concerns.
Public Comment Period
The time allowed for the public to express its views and concerns regarding an action by EPA (e.g. a Federal Register Notice of proposed rule-making, a public notice of a draft permit, or a Notice of Intent to Deny).
Public health action
A list of steps to protect public health.
Public health advisory
A statement made by ATSDR to EPA or a state regulatory agency that a release of hazardous substances poses an immediate threat to human health. The advisory includes recommended measures to reduce exposure and reduce the threat to human health.
Public health assessment (PHA)
An ATSDR document that examines hazardous substances, health outcomes, and community concerns at a hazardous waste site to determine whether people could be harmed from coming into contact with those substances. The PHA also lists actions that need to be taken to protect public health [compare with health consultation].
Public health hazard
A category used in ATSDR's public health assessments for sites that pose a public health hazard because of long-term exposures (greater than 1 year) to sufficiently high levels of hazardous substances or radionuclides that could result in harmful health effects.
Public health hazard categories
Public health hazard categories are statements about whether people could be harmed by conditions present at the site in the past, present, or future. One or more hazard categories might be appropriate for each site. The five public health hazard categories are no public health hazard , no apparent public health hazard , indeterminate public health hazard , public health hazard , and urgent public health hazard .
Public health statement
The first chapter of an ATSDR toxicological profile. The public health statement is a summary written in words that are easy to understand. The public health statement explains how people might be exposed to a specific substance and describes the known health effects of that substance.
Public health surveillance (epidemiologic surveillance)
The ongoing, systematic collection, analysis, and interpretation of health data. This activity also involves timely dissemination of the data and use for public health programs.
Public meeting
A public forum with community members for communication about a site. ( http://www.atsdr.cdc.gov/glossary.html ) Pulmonary airways: The lung is the essential respiration organ in air-breathing vertebrates , the most primitive being the lungfish . The two lungs are located in the chest on either side of the heart . Their principal function is to transport oxygen from the atmosphere into the bloodstream , and to release carbon dioxide from the bloodstream into the atmosphere. This exchange of gases is accomplished in the mosaic of specialized cells that form millions of tiny, exceptionally thin-walled air sacs called alveoli . The lungs also have non respiratory functions.
Quality Assurance/Quality Control
A system of procedures, checks, audits, and corrective actions to ensure that all EPA research design and performance, environmental monitoring and sampling, and other technical and reporting activities are of the highest achievable quality.
Radiation Measurement Units
Most scientists in the international community measure radiation using the System Internationale (SI), a uniform system of weights and measures that evolved from the metric system. In the United States, however, the conventional system of measurement is still widely used. Different units of measure are used depending on what aspect of radiation is being measured. For example, the amount of radiation being given off, or emitted, by a radioactive material is measured using the conventional unit curie (Ci), named for the famed scientist Marie Curie, or the SI unit becquerel (Bq). The radiation dose absorbed by a person (that is, the amount of energy deposited in human tissue by radiation) is measured using the conventional unit rad or the SI unit gray (Gy). The biological risk of exposure to radiation is measured using the conventional unit rem or the SI unit sievert (Sv).
Radioisotope
An unstable isotope of an element that decays or disintegrates spontaneously, emitting radiation. Approximately 5,000 natural and artificial radioisotopes have been identified.
Radionuclide
Radioactive particle, man-made (anthropogenic) or natural, with a distinct atomic weight number.
Receptor
Ecological entity exposed to a stressor.
Recycle/Reuse
Minimizing waste generation by recovering and reprocessing usable products that might otherwise become waste (.i.e. recycling of aluminum cans, paper, and bottles, etc.)
Reference Dose (RfD)
The RfD is a numerical estimate of a daily oral exposure to the human population, including sensitive subgroups such as children, that is not likely to cause harmful effects during a lifetime. RfDs are generally used for health effects that are thought to have a threshold or low dose limit for producing effects.
Registry
A systematic collection of information on persons exposed to a specific substance or having specific diseases [see exposure registry and disease registry ].
Relative Risk Assessment
Estimating the risks associated with different stressors or management actions.
Remedial Investigation
After a site is listed on the NPL, a remedial investigation/feasibility study (RI/FS) is performed at the Superfund site to establish site cleanup criteria; identify preliminary alternatives for remedial action; and support technical and cost analyses of alternatives. The remedial investigation is usually done with the feasibility study. Together they are usually referred to as the "RI/FS".
Remediation
1. Cleanup or other methods used to remove or contain a toxic spill or hazardous materials from a Superfund site;
2. for the Asbestos Hazard Emergency Response program, abatement methods including evaluation, repair, enclosure, encapsulation, or removal of greater than 3 linear feet or square feet of asbestos-containing materials from a building.
Renewable Energy Production Incentive (REPI)
Incentive established by the Energy Policy Act available to renewable energy power projects owned by a state or local government or nonprofit electric cooperative.
Resource Conservation and Recovery Act (1976, 1984) (RCRA)
This Act regulates management and disposal of hazardous wastes currently generated, treated, stored, disposed of, or distributed.
Risk
A measure of the probability that damage to life, health, property, and/or the environment will occur as a result of a given hazard.
Risk Assessment
Qualitative and quantitative evaluation of the risk posed to human health and/or the environment by the actual or potential presence and/or use of specific pollutants.
Risk communication
The exchange of information to increase understanding of health risks.
Risk Management
The process of evaluating and selecting alternative regulatory and non-regulatory responses to risk. The selection process necessarily requires the consideration of legal, economic, and behavioral factors.
Risk Reduction
The goal of risk reduction is to reduce the risk to life and property, which includes existing structures and future construction, in the pre and post-disaster environments. This is achieved through regulations, local ordinances, land use and building practices, and Mitigation projects that reduce or eliminate long-term risk from hazards and their effects
Rodenticide
A chemical or agent used to destroy rats or other rodent pests, or to prevent them from damaging food, crops, etc.
Route of Exposure
The avenue by which a chemical comes into contact with an organism, e.g., inhalation, ingestion, dermal contact, injection.
Safety factor
See SN uncertainty factor.
Sample
A portion or piece of a whole. A selected subset of a population or subset of whatever is being studied. For example, in a study of people the sample is a number of people chosen from a larger population [see population ]. An environmental sample (for example, a small amount of soil or water) might be collected to measure contamination in the environment at a specific location.
Sample size
The number of units chosen from a population or an environment.
Sampling Strategy
A detailed outline of which measurements will be taken at what times, on which material, in what manner, and by whom. Sampling plans should be designed in such a way that the resulting data will contain a representative sample of the parameters of interest and allow for all questions, as stated in the goals, to be answered.
Sanitary Landfill
(See: landfills.)
Secondary infection
Secondary infection occurs during or after treatment of a primary infection because the normal bacterial flora is destroyed, allowing yeast to flourish.
Select Agent Program
The Public Health Security and Bioterrorism Preparedness and Response Act of 2002 ( Public Law 107-188; June 12, 2002 ) requires that the United States improve its ability to prevent, prepare for, and respond to acts of bioterrorism and other public health emergencies that could threaten either public health and safety or American Agriculture. It necessitates that individuals possessing, using, or transferring agents or toxins deemed a severe threat to public, animal or plant health, or to animal or plant products notify either the Secretary of the Department of Health and Human Services (HHS) or the Secretary of the Department of Agriculture (USDA). In accordance with the Act, implementing regulations detailing the requirements for possession, use, and transfer for select agents and toxins were published by HHS ( 42 CFR part 73 ) and by USDA ( 9 CFR part 121 and 7 CFR part 331 ) . Registration of an entity requires that an "Application for Laboratory Registration for Possession, Use, and Transfer of Select Agents and Toxins" ( APHIS/CDC Form 1 ) should be completed and submitted to either HHS Centers for Disease Control ( CDC ) or to USDA Animal Plant Health Inspection Service (APHIS) within seven days. Registration also requires that the U.S. Department of Justice ( DOJ ) complete a security risk assessment ( SRA ) for the facility, its owners, and the designated responsible official.
Sievert (SV)
The international system (SI) unit for dose equivalent equal to 1 Joule/kilogram. 1 sievert = 100 rem. Named for physicist Rolf Sievert.
Signaling Pathways
A series of specific actions in a cell in which a signal is passed from one molecule to the next in the series. Signaling pathways are used to control many cell functions, such as cell division and programmed cell death.
Silicosis
Silicosis is a disabling, nonreversible and sometimes fatal lung disease caused by overexposure to respirable crystalline silica. Silica is the second most common mineral in the earth's crust and is a major component of sand, rock, and mineral ores. Overexposure to dust that contains microscopic particles of crystalline silica can cause scar tissue to form in the lungs (fibrosis), which reduces the lungs' ability to extract oxygen from the air we breathe.
Single nucleotide polymorphism (SNP)
DNA sequence variations that occur when a single nucleotide (A, T, C, or G) in the genome sequence is altered. Each individual has many single nucleotide polymorphisms that together create a unique DNA pattern for that person. SNPs promise to significantly advance our ability to understand and treat human disease.
Site Inspection
The collection of information from a Superfund site to determine the extent and severity of hazards posed by the site. It follows and is more extensive than a preliminary assessment. The purpose is to gather information necessary to score the site, using the Hazard Ranking System, and to determine if it presents an immediate threat requiring prompt removal.
Slope factor
Value, in inverse concentration or dose units, derived from the slope of a dose-response curve; in practice, limited to carcinogenic effects with the curve assumed to be linear at low concentrations or doses. The product of the slope factor and the exposure is taken to reflect the probability of producing the related effect.
RT concentration-effect curve , concentration-response curve , dose , dose-effect curve , dose-response curve .
Social Capital
The fabric of a community and the community pool of human resources available to it is often called its "social capital." This term refers to the individual and communal time and energy that is available for such things as community improvement, social networking, civic engagement, personal recreation, and other activities that create social bonds between individuals and groups.
Solubility
The amount of mass of a compound that will dissolve in a unit volume of solution. Aqueous Solubility is the maximum concentration of a chemical that will dissolve in pure water at a reference temperature.
Solvent
A liquid capable of dissolving or dispersing another substance (for example, acetone or mineral spirits)
Somatic
1. Pertaining to the body as opposed to the mind.
2. Pertaining to nonreproductive cells or tissues.
3. Pertaining to the framework of the body as opposed to the viscera.
Source of contamination
The place where a hazardous substance comes from, such as a landfill, waste pond, incinerator, storage tank, or drum. A source of contamination is the first part of an exposure pathway.
Special populations
People who might be more sensitive or susceptible to exposure to hazardous substances because of factors such as age, occupation, sex, or behaviors (for example, cigarette smoking). Children, pregnant women, and older people are often considered special populations.
Stakeholder
Any organization, governmental entity, or individual that has a stake in or may be impacted by a given approach to environmental regulation, pollution prevention, energy conservation, etc.
Statistics
A branch of mathematics that deals with collecting, reviewing, summarizing, and interpreting data or information. Statistics are used to determine whether differences between study groups are meaningful. Substance
A chemical.
Substance-specific applied research
A program of research designed to fill important data needs for specific hazardous substances identified in ATSDR's toxicological profiles . Filling these data needs would allow more accurate assessment of human risks from specific substances contaminating the environment. This research might include human studies or laboratory experiments to determine health effects resulting from exposure to a given hazardous substance.
Substrate (in biology)
Substance material on which an enzyme acts. Surface on which an organism grows or to which is attached.
Susceptible populations
A susceptible population is a group who may experience more severe adverse effects atcomparable levels or adverse effects at lower exposure levels than the general population. The greater response of these sensitive subpopulations may be a result of a variety of intrinsic or extrinsic factors.
Sustainable Development
"Development that meets the needs of the present without compromising the ability of future generations to meet their own needs." — from the World Commission on Environment and Development's
Sustainable Management
Defined under the RMA as managing the use, development, and protection of natural and physical resources in a way, or at a rate, which enables people and communities to provide for their social, economic, and cultural well being and for their health and safety while (a) sustaining the potential of natural and physical resources (excluding minerals) to meet the reasonably foreseeable needs of future generations; (b) safeguarding the life-supporting capacity of air, water, soil, and ecosystems; and (c) avoiding, remedying, or mitigating any adverse effects of activities on the environment.
State Emergency Response Commission (SERC)
Commission appointed by each state governor according to the requirements of SARA Title III. The SERCs designate emergency planning districts, appoint local emergency planning committees, and supervise and coordinate their activities.
State Implementation Plans (SIP)
EPA approved state plans for the establishment, regulation, and enforcement of air pollution standards.
Superfund
The program operated under the legislative authority of CERCLA and SARA that funds and carries out EPA solid waste emergency and long-term removal and remedial activities. These activities include establishing the National Priorities List, investigating sites for inclusion on the list, determining their priority, and conducting and/or supervising cleanup and other remedial actions
Superfund Amendments and Reauthorization Act (SARA)
In 1986, SARA amended the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA) and expanded the health-related responsibilities of ATSDR. CERCLA and SARA direct ATSDR to look into the health effects from substance exposures at hazardous waste sites and to perform activities including health education, health studies, surveillance, health consultations, and toxicological profiles.
Surface Water
All water naturally open to the atmosphere (rivers, lakes, reservoirs, ponds, streams, impoundments, seas, estuaries, etc.)
Surveillance
[see public health surveillance ]
Survey
A systematic collection of information or data. A survey can be conducted to collect information from a group of people or from the environment. Surveys of a group of people can be conducted by telephone, by mail, or in person. Some surveys are done by interviewing a group of people [see prevalence survey].
Synergistic effect
A biologic response to multiple substances where one substance worsens the effect of another substance. The combined effect of the substances acting together is greater than the sum of the effects of the substances acting by themselves [see additive effect and antagonistic effect ].
Target organ(s)
Organ(s) in which the toxic injury manifests itself in terms of dysfunction or overt disease
WHO, 1979
RT receptor
T cell
See T lymphocyte .
T-lymphocyte
One type of white blood cell that attacks virus-infected cells, foreign cells, and cancer cells. T lymphocytes also produce a number of substances that regulate the immune response. Also called T cell.
TD50
May be defined as follows: for a given target site(s), if there are no tumors in control animals, then TD50 is that chronic dose-rate in mg/kg body wt/day which would induce tumors in half the test animals at the end of a standard lifespan for the species. Since the tumor(s) of interest often does occur in control animals, TD50 is more precisely defined as: that dose-rate in mg/kg body wt/day which, if administered chronically for the standard lifespan of the species, will halve the probability of remaining tumorless throughout that period. A TD50 can be computed for any particular type of neoplasm, for any particular tissue, or for any combination of these. The range of statistically significant TD50 values for chemicals in the CPDB that are carcinogenic in rodents is more than 10 million-fold.
Technical safety services (TSS)
Technical Safety Services, Inc. has built its foundation by providing superior testing and certification services to the most demanding Fortune 100 biotechnology, pharmaceutical and medical device companies in the nation. Our ability to listen to clients' needs, in addition to our flexibility, innovation, and precision, are the qualities that distinguish TSS from all other service companies
Temperature Danger Zone
The "danger zone" is the range of temperatures at which bacteria can grow - usually between 40° and 140° F (4° and 60° C). For food safety, it's important to keep food below or above the "danger zone."
Teratogen
A substance capable of causing birth defects.
Threshold
The lowest dose of a chemical at which a specified measurable effect is observed and below which it is not observed. // Dose or exposure concentration below which a defined effect will not occur.
Total maximum daily load
A regulatory term in the U.S. Clean Water Act (CWA), describing a value of the maximum amount of a pollutant that a body of water can receive while still meeting water quality standards . [1] Alternatively, TMDL is an allocation of that pollutant deemed acceptable to the subject receiving waters . TMDLs have been used extensively by the United States Environmental Protection Agency (EPA) and state environmental agencies in implementing the CWA by establishing maximum pollution limits for industrial wastewater dischargers. EPA published regulations in 1992 establishing TMDL procedures. [2] Application of TMDL has broadened significantly in the last decade to include many watershed-scale efforts. This process incorporates both point source and nonpoint source pollutants within a watershed .
Toxic agent
Chemical or physical (for example, radiation, heat, cold, microwaves) agents that, under certain circumstances of exposure, can cause harmful effects to living organisms
Toxicant
A harmful substance or agent that may injure an exposed organism.
Toxicological Profile
An examination, summary, and interpretation of a hazardous substance to determine levels of exposure and associated health effects.
Toxicology
Scientific discipline involving the study of the actual or potential danger presented by the harmful effects of substances (poisons) on living organisms and ecosystems, of the relationship of such harmful effects to exposure, and of the mechanisms of action, diagnosis, prevention and treatment of intoxications
NT chemical toxicology
Toxic substances Control Act (TSCA)
regulates the introduction of new or already existing chemicals. It grandfathered most existing chemicals, in contrast to the Registration, Evaluation and Authorization of Chemicals (REACH) legislation of the European Union . However, as explained below, the TSCA specifically regulates polychlorinated biphenyl (PCB) products. The TSCA is found in United States law at 15 USC (C. 53) 2601-2692 . It is administered by the U.S. Environmental Protection Agency (EPA). Subchapter I of the TSCA, "Control of Toxic Substances," is the original substance of the 1976 act, PL 94-469, including regulation of polychlorinated biphenyl (PCB) products.
Toxin
Poisonous substance produced by a biological organism such as a microbe, animal or plant
PS venom
Trauma
a physical injury or wound caused by an external force which may cause death or permanent disability. Trauma is also used to describe severe emotional or psychological shock or distress.
Tumor
1. Any abnormal swelling or growth of tissue, whether benign or malignant.
2. An abnormal growth, in rate and structure, that arises from normal tissue, but serves no physiological function
SN neoplasm
Tumor initiation
A process in which normal cells are changed so that they are able to form tumors. Substances that cause cancer can be tumor initiators.
Tumor progression
Increase in the size of a tumor or spread of cancer in the body.
Tumor promotion
A process in which existing tumors are stimulated to grow. Tumor promoters are not able to cause tumors to form.
Uncertainty Factor
One of several factors used in calculating the reference dose from experimental data. UFs are intended to account for
(1) the variation in sensitivity among humans
(2) the uncertainty in extrapolating animal data to humans
(3) the uncertainty in extrapolating data obtained in a study that covers less than the full life of the exposed animal or human
(4) the uncertainty in using LOAEL data rather than NOAEL data.
Unit risk (as used by the USEPA)
Incremental upper-boundary lifetime risk estimated to result from lifetime exposure to an agent if it is in air at a concentration of 1 mg/m3 or in the water at a concentration of 1 mg/L
Urgent public health hazard
A category used in ATSDR's public health assessments for sites where short-term exposures (less than 1 year) to hazardous substances or conditions could result in harmful health effects that require rapid intervention.
U.S. Department of Defense (DoD)
The Defense Department manages an inventory of installations and facilities to keep Americans safe. The Department's physical plant is huge by any standard, consisting of more than several hundred thousand individual buildings and structures located at more than 5,000 different locations or sites. When all sites are added together, the Department of Defense utilizes over 30 million acres of land.
U.S. Department of Energy (DOE)
The Department of Energy's overarching mission is to advance the national, economic, and energy security of the United States; to promote scientific and technological innovation in support of that mission; and to ensure the environmental cleanup of the national nuclear weapons complex.
U.S Department of Health and Human Services (DHHS)
The Department of Health and Human Services is the United States government's principal agency for protecting the health of all Americans and providing essential human services, especially for those who are least able to help themselves.
U.S Department of Homeland Security
In 2002, the Homeland Security Act was created as a vehicle to mobilize and organize the nation to secure the US from terrorist attacks. In order for this mission to be successful, it requires focused effort from our entire society. The Homeland Security was established, primarily, to unify, guide and coordinate this vast national effort. The DHS has developed its own high level strategic plan, a vision, mission statements, strategic goals and objectives to guide the approximately 180,000 DHS employees that daily perform this very important task.
U.S. Environmental Protection Agency (EPA)
The mission of the Environmental Protection Agency is to protect human health and the environment. Since 1970, EPA has been working for a cleaner, healthier environment for the American people. View the Agency's complete strategic plan , annual report , and policy resources.
U.S. Food and Drug Administration
The FDA is responsible for protecting the public health by assuring the safety, efficacy, and security of human and veterinary drugs, biological products, medical devices, our nation's food supply, cosmetics, and products that emit radiation. The FDA is also responsible for advancing the public health by helping to speed innovations that make medicines and foods more effective, safer, and more affordable; and helping the public get the accurate, science-based information they need to use medicines and foods to improve their health.
Vector
1. An organism, often an insect or rodent which carries disease.

2. Plasmids, viruses, or bacteria used to transport genes into a host cell. A gene is placed in the vector; the vector then "infects" the bacterium.
Ventilation/Suction
The act of admitting fresh air into a space in order to replace stale or contaminated air; achieved by blowing air into the space. Similarly, suction represents the admission of fresh air int
Virus
A virus is an extremely tiny infectious agent that is only able to live inside a cell. To reproduce, a virus invades a cell within the body of a human or other creature. Once replicated, the new viruses leave the host cell and are ready to invade others.
Volatile
Any substance that evaporates readily.
Volatile Organic Compound (VOC)
Any organic compound that participates in atmospheric photochemical reactions except those designated by EPA as having negligible photochemical reactivity.
Waste Minimization
Measures or techniques that reduce the amount of wastes generated during industrial production processes; term is also applied to recycling and other efforts to reduce the amount of waste going into the waste stream.
Wastewater Treatment Plant
A facility containing a series of tanks, screens, filters, and other processes by which pollutants are removed from water. Most treatments include chlorination to attain safe drinking water standards.
Waterborne Disease Outbreak
The significant occurrence of acute illness associated with drinking water from a public water system that is deficient in treatment, as determined by appropriate local or state agencies.
Watershed
The land area that drains into a stream; the watershed for a major river may encompass a number of smaller watersheds that ultimately combine at a common point.
Water Quality Management
Planning for the protection of a water's quality for various Beneficial Uses , for theprovision of adequate wastewater collection, treatment, and disposal for municipalities and industries, and for activities that might create water quality problems, and regulating and enforcing programs to accomplish the planning goals and laws and regulations dealing with water pollution control.
Weapons of Mass Destruction
- Any explosive or incendiary device, as defined in Title 18 USC, Section 921: bomb, grenade, rocket, missile, mine, or other device with a charge of more than four ounces;
- Any weapon designed or intended to cause death or serious bodily injury through the release, dissemination, or impact of toxic or poisonous chemicals or their precursors;
- Any weapon involving a disease organism; or
- Any weapon designed to release radiation or radioactivity at a level dangerous to human life.
X-rays
Penetrating electromagnetic radiation (photon) having a wavelength that is much shorter than that of visible light. These rays are usually produced by excitation of the electron field around certain nuclei. In nuclear reactions, it is customary to refer to photons originating in the nucleus as x-rays
Zoonotic diseases
Any disease and/or infection which is naturally "transmissible from vertebrate animals to man" is classified as a zoonosis according to the PAHO publication "Zoonoses and communicable diseases common to man and animals". Over 200 zoonoses have been described and they are known since many centuries. They involve all types of agents: bacteria, parasites, viruses and unconventional agents
Biodegradable
Capable of decomposing under natural conditions.
Bioterrorism
Terrorism by intentional release or dissemination of biological agents ( bacteria , viruses or toxins ); these may be in a naturally-occurring or in a human-modified form.
Cancer
Any one of a group of diseases that occur when cells in the body become abnormal and grow or multiply out of control.
Central nervous system
The part of the nervous system that consists of the brain and the spinal cord.
Completed exposure pathway
[see exposure pathway ].
Contaminant
Any physical, chemical, biological, or radiological substance or matter that has an adverse effect on air, water, or soil.
Epidemiology
Study of the distribution of disease, or other health-related states and events in human populations, as related to age, sex, occupation, ethnicity, and economic status in order to identify and alleviate health problems and promote better health.
Lumen
the cavity of a tubular organ <the lumen of a blood vessel>
Morbidity
Rate of disease incidence.
Mortality
Death rate.
Molecule
The smallest division of a compound that still retains or exhibits all the properties of the substance.
Exposure-effect relationship
See NT concentration-effect relationship , dose-effect relationship
Hydrophilic
Having a strong affinity for water.
Hydrophobic
Having a strong aversion for water.
Incidence
The number of new cases of disease in a defined population over a specific time period [contrast with prevalence]. Often confused with incidence rate.
Ionizing radiation
Any radiation capable of displacing electrons from atoms or molecules, thereby producing ions. Some examples are alpha, beta, gamma, x-rays, neutrons, and ultraviolet light. High doses of ionizing radiation may produce severe skin or tissue damage.

Radiation that can strip electrons from atoms; e.g. alpha, beta, and gamma radiation.
Mutation
A change (damage) to the DNA, genes, or chromosomes of living organisms.
What is Environmental Health?
Environmental health can be viewed as the basis for the development of public health because as societies evolved, communities had to deal with multiple environmental hazards. Safe water, clean air, safe foods are all pivotal to human survival.
What are three of public health's principal activities and how do they related to environmental health?
Three of public health's principal activities, "the science and art of preventing disease, prolonging life, and promoting health and efficiency through organized community efforts"; "successive re-defining of the unacceptable"; and "fulfilling society's interest in assuming conditions in which people can be healthy," provides a fertile foundation for the field of environmental health
How does the World Health Organization define Environmental Health?
The World Health Organization defines environmental health as "those aspects of human health, disease, and injury that are determined by physical, chemical, biological, social, and psychosocial factors." As a consequence, environmental health encompasses many areas of science from toxicology and risk assessment to food safety and climate change.
T/F: The scope of Environmental health studies are purposely broad
True.
Equally broad is the scope of environmental health: traditional focus areas such as water and air pollution have become have become increasingly important globally, while advances in genomics are contributing to identifying biomarkers of disease susceptibility.
T/F: Environmental health science, policy and practice are not linked.
False.
Environmental health science, policy and practice are inextricably linked.
T/F: Social determinants of health affect how environmental health is practiced.
True.
Social determinants of health affect how environmental health is practiced.
T/F: Environmental Health does not use a systems approach
False.
Practicing environmental health requires a systems approach; and ecosystem services such as purification of air and water and detoxification of wastes are increasingly related to modern era environmental health.
T/F: Environmental pollution can occur in many forms, differ in type and geographic impact, and can affect different populations.
True
Environmental pollution can occur in many forms, differ in type and geographic impact, and can affect different populations.
What are the main types of environmental pollution?
The main types of environmental pollution involve air, water, soil, solid and hazardous waste, radiation, and noise.
T/F: Environmental contaminants are significant contributors to pollution.
True
Environmental contaminants are significant contributors to pollution.
What is the general definition of a contaminant?
The general definition of a contaminant is "a substance that is either present in an environment where it does not belong or is present at levels that might cause harmful health effects".
How can a contaminant to cause adverse human health effects?
For a contaminant to cause adverse human health effects, either directly or through damage to the ecosystem, exposure to that substance must occur.
How can humans be exposed to a contaminant?
Exposure to an environmental contaminant is defined as contact by an individual with a substance by swallowing, breathing, or touching the skin or eyes. Exposure may be short term (acute exposure of less than 24 hours), of intermediate duration (exposures of weeks to months), or long term (chronic exposure of months to years). Exposure can also be defined as contact over time between a person and one or more biologic, chemical or physical agents
What is the environmental exposure pathway?
An environmental exposure pathway consists of five elements:

1. The contaminant source
2. The contaminated environmental media
3. The exposure point(s)
4. The exposure routes
5. The receptor population(s)
What kinds of contaminant sources are there?
The contaminant source can be either natural, e.g. volcanic emissions, or anthropogenic, such as industrial wastes or an uncontrolled industrial operation. Environmental media serve as the mechanism of transport for the contaminant. Air, both indoor and outdoor; surface- and groundwater; soil, and animal and plant biota can aid in the transport of toxicants or may be consumed following contamination; and they represent the key environmental media capable of "transporting" contaminants to exposure points.
What is an exposure point? Give an example.
An exposure point is the place or "point" where a person can come into contact with a substance present in the environment. Examples of exposure points include playgrounds, a residence, a water tap, and a yard.
How can contaminants get into the body?
For exposure to occur a contaminant has to enter the body. Inhalation, ingestion, dermal contact, and in the case of infants also ingestion of breast milk, are all considered exposure routes. In addition to the chemical properties and the susceptibility of the exposed populations, the effectiveness of a toxicant and response of the body to a toxicant depends on the route of exposure routes.
T/F: All five elements of the exposure pathway must be present for the pathway to be considered "completed".
True
All five elements of the exposure pathway must be present for the pathway to be considered "completed".
T/F: An analysis of exposure pathways lays the foundation for evaluating the public health implications of all current, potential (future), and past exposures.
True
An analysis of exposure pathways lays the foundation for evaluating the public health implications of all current, potential (future), and past exposures.
What is the first empirical step towards documenting exposure?
The presence of a completed exposure pathway represents the first empirical step towards documenting exposure.
What is the field in environmental health dedicated to determining the extent of exposure?
Exposure assessment is that field in environmental health dedicated to determining the extent of exposure and hence one of the important aspects of the potential of a toxicant to be harmful.
What is the hierarchy of data to assess exposure giving the highest preference to quantifiable data?
In order of preference, they are: quantified individual exposure measurements; quantified ambient exposure measurements; quantified surrogates of exposure; distance 'from' and duration 'of' exposure; distance or duration of exposure; residence or employment proximity to the exposure source; and residence or employment in geographic area.
T/F: The results of the exposure assessment provide a valuable foundation for further risk assessment and toxicological evaluations.
True.
The results of the exposure assessment provide a valuable foundation for further risk assessment and toxicological evaluations.
What is the underlying science of environmental health?
Whether addressing issues of air pollution, climate change, disasters or injuries, toxicology is, with some exceptions such as radiation and infectious pathogens, the underlying science of environmental health.
What is Toxicology is traditionally defined as?
Toxicology is traditionally defined as "the study of adverse effects of chemicals on biological systems.
T/F: Toxicology integrates many different areas of science and encompasses both basic, mechanistic approaches as well as applications in population studies.
True
Toxicology integrates many different areas of science and encompasses both basic, mechanistic approaches as well as applications in population studies.
Within environmental public health what does toxicology aim to do?
Within environmental public health, toxicology supports efforts to determine under which conditions a toxicant can be harmful to humans.
What four key toxicokinetic processes take place when exposure to a toxicant occurs?
Once exposure to a toxicant occurs, four key toxicokinetic processes take place: absorption, distribution, metabolism and excretion.
T/F: Following contact with a toxicant, the route of exposure plays an important role in the efficiency and the effectiveness of the absorption process.
True
Following contact with a toxicant, the route of exposure plays an important role in the efficiency and the effectiveness of the absorption process.
What are the primary routes of absorption for toxicants?
Ingestion, inhalation, and dermal contact are considered the primary routes of absorption.
What are the secondary routes of absorption for toxicants?
Breast milk, transplacental, intrauterine are classified as secondary routes of absorption.
Why is the gastrointestinal tract an effective absorption system?
The gastrointestinal tract with its large surface area and numerous nutrient transport mechanisms represents an effective absorption system.
How is absorption via the lungs is determined?
Absorption via the lungs is determined by the characteristics of the alveoli. For example, water soluble compounds are easily absorbed through the alveolar system while small size particulates (2.5 um or smaller) are much easier absorbed than large ones. Lipid soluble compounds have more difficulty to traverse the alveoli and enter the bloodstream.
What is the most effective way to absorb lipid soluble toxicants?
Absorption via the dermis is most effective for lipid soluble toxicants.
What does distribution via the blood stream to the site of action, often referred to as the target organ/site, depend on?
Distribution via the blood stream to the site of action, often referred to as the target organ/site, depends both on the chemical characteristics of the compound and the mechanism of absorption.
How are lipid soluble chemicals typically carried through the bloodstream?
Lipid soluble chemicals are typically carried through the bloodstream by binding to proteins, often albumin.
T/F: Lipid soluble chemicals are typically carried through the bloodstream by binding to proteins, often albumin. In general, the laws of diffusion apply (high to low concentration gradient).
True
Lipid soluble chemicals are typically carried through the bloodstream by binding to proteins, often albumin. In general, the laws of diffusion apply (high to low concentration gradient).
How are chemicals entering the body through the gastrointestinal system carried in the blood stream?
Chemicals entering the body through the gastrointestinal system are carried in the blood stream through the portal vein to the liver and may undergo "first pass" metabolism.
What are some examples of enhancing mechanisms which enhance and counteract distribution to the target site?
Several mechanisms exist which enhance and counteract distribution to the target site. Examples of enhancing mechanisms include specialized transport across the plasma membrane through ion channels and endocytosis, while prolonged binding to plasma proteins delays the availability of the toxicant at the target site.
Following distribution in the body, most chemicals are ___________.
Following distribution, most chemicals are metabolized.
This biotransformation process can either lead to _____________ resulting in the formation of harmful products (metabolic activation) or _____________ resulting either in the elimination of the toxicant or prevention of its formation.
This biotransformation process can either lead to toxication resulting in the formation of harmful products (metabolic activation) or de-toxication resulting either in the elimination of the toxicant or prevention of its formation.
Toxication results in conversion of what four chemical configurations?
Toxication results in conversion of four chemical configurations: electrophiles (electron-deficient); free radicals (containing highly reactive unpaired electrons); nucleophiles (negative charge- react with electrophiles); and redox- molecules (can donate and accept electrons).
What is involved in Phase I of Biotransformation?
Phase I involves oxidation, reduction, and hydrolysis. Oxidation and dehydrogenation are more common than reduction.
What is involved in Phase II of Biotransformation?
Phase II involves the attachment of a molecular side-chain to the chemical in a process called chemical conjugation. This reaction usually makes it less toxic, more water soluble, and facilitates urinary excretion.
Oxidation is aided by __________ __________
Oxidation is aided by microsomal enzymes
What is the most well-known phase I enzyme system and what is it recognized for?
The most well-known phase I enzyme system is the cytochrome P450 system. This system is traditionally recognized as the most efficient mechanism to create free radicals.
________________ in the P450 system can result in a decrease or increase of the metabolic capability of some people for certain chemical compounds, potentially increasing or decreasing their risks for adverse health effects following exposure to those compounds.
Polymorphism in the P450 system can result in a decrease or increase of the metabolic capability of some people for certain chemical compounds, potentially increasing or decreasing their risks for adverse health effects following exposure to those compounds.
Name some things that may influence an individual's biotransformation capacity.
Existing disease burden, nutritional status, and interaction with other xenobiotics, such as medications, may also influence an individual's biotransformation capacity.
What happens when Phase I and II biotransformation processes occur consecutively?
When Phase I and II biotransformation processes occur consecutively, the result is often an increase in polarity and decrease in fat solubility, ultimately leading to a greater opportunity for urinary excretion.
Excretion involves what four major routes?
Excretion involves four major routes: 1) through the kidney via urine; 2) through the liver and the gastrointestinal system via feces; 3) through the pulmonary system via exhaled air; and 4) via breast milk.
Excretion via the kidney is facilitated by _______ _________ ____________ for all molecules 70,000 Daltons in size or smaller.
Excretion via the kidney is facilitated by passive glomerular filtration for all molecules 70,000 Daltons in size or smaller.
Compounds bound to larger serum proteins are excreted via active _____ __________.
Compounds bound to larger serum proteins are excreted via active tubular secretion.
T/F: Passive tubular diffusion from the serum to the tubules (organic bases) and in the opposite direction (reabsorption of lipid-soluble molecules) also influences excretion via urine.
True
Passive tubular diffusion from the serum to the tubules (organic bases) and in the opposite direction (reabsorption of lipid-soluble molecules) also influences excretion via urine.
Toxicants delivered to the liver by the gastrointestinal system are excreted into the ____.
Toxicants delivered to the liver by the gastrointestinal system are excreted into the bile.
The biliary excretion system is analogous to _______ _________.
The biliary excretion system is analogous to tubular secretion.
T/F: Unless reabsorption via the intestinal wall takes place, compounds excreted in the bile leave the body via feces.
True
Unless reabsorption via the intestinal wall takes place, compounds excreted in the bile leave the body via feces.
T/F: Passive diffusion facilitates excretion of volatiles and vapors via exhaled air.
True
Passive diffusion facilitates excretion of volatiles and vapors via exhaled air.
How does the fat solubility of compounds influences the timeframe of excretion via the pulmonary system?
The fat solubility of compounds influences the timeframe of excretion via the pulmonary system; the higher the fat solubility the longer it takes for a chemical to be excreted.
T/F: Excretion via breast milk poses a risk to infants, a vulnerable population from an environmental public health perspective.
True
Excretion via breast milk poses a risk to infants, a vulnerable population from an environmental public health perspective.
T/F: Excretion via sweat and saliva also contribute to elimination of toxicants from the body.
True
Excretion via sweat and saliva also contribute to elimination of toxicants from the body.
Toxicology studies are primarily conducted in ______ and are important in determining dose-response relationships.
Toxicology studies are primarily conducted in animals and are important in determining dose-response relationships.
T/F: Dose-response studies are critical to understand how much of a toxicant can cause an adverse effect to a specific target tissue.
True
Dose-response studies are critical to understand how much of a toxicant can cause an adverse effect to a specific target tissue. These studies typically occur in controlled conditions where dose, duration, and route of administration are predetermined to evaluate specific adverse effects.
Give examples of "benchmarks" used to evaluate the adverse health effects in humans.
The Lethal Dose that kills 50% of the test animals (LD50) and the No Observed Adverse Health Effect Level (NOAEL) are examples of "benchmarks" used to evaluate the adverse health effects in humans.
Key factors influencing toxicity are:
Key factors influencing toxicity are the dose at the target organ, the potency of the toxicant, and the susceptibility of the receptor population.
Figure 1 shows three typical dose response curves. The linear relationship represents increasing effects with increasing dose; the "hockey stick" formation depicts the presence of a threshold, which helps determine the NOAEL which is the highest dose where no toxicity is observed. The third J-shaped curve represents a phenomenon well-known in pharmacology called hormesis. This relationship indicates a toxic effect at low doses, followed by a homeostatic effect, and at higher doses toxicity resembling for example target organ damage.
Describe the image
Toxicologically, chemicals can generate a ________ ____________ ___________ which is different than that of the chemicals by themselves.
Toxicologically, chemicals can generate a concurrent toxic effect which is different than that of the chemicals by themselves.
What is an additive effect in toxicology?
An additive effect results when the concurrent toxicity of chemicals represents the sum of their individual adverse effects (4+3=7).
_________ occurs when the concurrent toxicity of the chemicals is far greater than their simple sum (1+1=10).
Synergism occurs when the concurrent toxicity of the chemicals is far greater than their simple sum (1+1=10).
What is potentiation?
An interaction between two chemicals with differing target organs, (one without adverse effects to the same target organ) is referred to as potentiation ( 0+2= 8);
What is antagonism
antagonism represents the blocking at varying degrees of adverse effects of one chemical by the other (1+-1= 0; 1+ 4= 2).
A _________ can be any measurement that characterizes exposure, susceptibility, or response in a biological system.
A biomarker can be any measurement that characterizes exposure, susceptibility, or response in a biological system.
How are biomarkers used?
Biomarkers are used in hazard assessments, risk assessments and in epidemiologic studies.
_________ is the presentation of a hazardous substance at the portal of entry into the human.
Exposure is the presentation of a hazardous substance at the portal of entry into the human.
What are some portals of entry for a hazardous substance?
Portals of entry may be the nose, mouth, skin, or other unique methods such as injection.
What are some routes of exposure for a hazardous substance?
Routes of exposure are inhalation, ingestion, dermal absorption.
Even when attempting to directly measure exposure to a toxic substance, _________ ___________ moderate the intake and delivery of a toxicant to the target organ or tissue.
Even when attempting to directly measure exposure to a toxic substance, physiological factors moderate the intake and delivery of a toxicant to the target organ or tissue.
What would the direct measure of exposure entail?
The direct measure of exposure would be measuring the toxicant in the environmental media presented to the person, such as a personal sampling measurement of a chemical in air near the nose and mouth.
The _________ of exposure may be a biological dose measurement in a person.
The biomarker of exposure may be a biological dose measurement in a person.
T/F: many physiological changes are measured as a biomarker of effect.
True
many physiological changes are measured as a biomarker of effect.
What are Biomarkers of susceptibility used for?
Biomarkers of susceptibility are used to identify biological characteristics among people in a population for whom exposure to a toxicant might have greater toxic effects.
What can Biomarkers be used in epidemiology studies for?
Biomarkers may be used to in epidemiology studies to document the relationship between exposure and adverse health effects by examining the linkages between exposure to a hazardous substance and adverse health effects.
Describe the linkages between exposure to a hazardous substance and adverse health effects.
Environmental → Biological → Exposure to → Physiologic → Disease
Exposure Uptake Target Tissue Changes
How can chemicals be categorized?
Chemicals can be categorized by chemical class, by exposure source, and by target organ.
Why does the category of environmental agents encompass so many public health hazards?
Hazards generally considered within the purview of environmental heath are commonly thought of as hazardous chemicals, but other hazardous agents may cause harm. Factors can include physical agents such as radiation and sound waves. Also, traditional environmental health includes sanitation actions that prevent exposure to infectious agents such as those which cause food and water borne illnesses and the control of disease vectors such as rodents. Allergens like dust mites and cockroaches have been recognized as potent risk factors for asthma. Therefore, the category of environmental agents may encompass many public health hazards.
History of lead and its use that has lead to human exposure.
Lead is a metal with the longest history of use by humans. It has been mined for thousands of years and a medical description of its toxic effects was reported among Roman miners. The use of lead throughout the late nineteenth and twentieth centuries was an important public health hazard mainly due to its use in lead based paint and gasoline. Lead use in paint took advantage of pigment properties of lead compounds. The dusting, or chalking property, of white lead-based paint made painted surfaces continue to appear white, but this characteristic allowed lead contaminated dust to be freely available. Childhood hand-to-mouth behavior resulted in lead exposure from contaminated indoor dust and outdoor soil of painted houses. Lead for use in house paint was banned in 1978. Tetraethyl lead was added to gasoline to enhance the octane rating. The lead was emitted in the automobile exhaust. This significant source of human exposure was phased out to a complete ban in 1995 due to the Clear Air Act Amendments of 1990. Lead used for water pipes could also be found throughout the mid-twentieth century, but the use of leaded pipe has been replaced by copper and plastic pipe. In 1998, the Safe Drinking Water Act prohibited the use of lead piping. Occupational exposures to lead still occur in the steel, manufacturing, smelting, automobile trades, and other sometimes unexpected industries such as rubber manufacturing. Lead is a common contaminant of hazardous waste sites, especially near mining and smelting operations. This source has been a significant human exposure route among some communities.
What organ systems is lead toxic to?
Lead is toxic to many organ systems, especially the renal and neurologic systems. At high exposure levels, lead can cause death. Non-lethal, but severe, toxicities of lead include neurological impairment and neurobehavioral deficits in children. An additional important toxicity of lead has been the adverse effects on the hematopoietic system by inhibiting the activities of several enzymes involved in heme biosynthesis.
History and exposure of Mercury.
Mercury occurs naturally in the environment and exists in several forms including metallic, or elemental mercury, inorganic mercury, and organic mercury. Metallic mercury is a shiny, silver-white metal that is a liquid at room temperature. Metallic mercury is the elemental or pure form of mercury (i.e., it is not combined with other elements). Metallic mercury is best recognized by most people but is seldom encountered as it has been replaced in many consumer products. Electric coal burning power generation facilities are also important sources of exposure. Inorganic and organic forms of mercury have produced significant exposures for humans through unique exposure routes and elevated mercury concentrations in seafood. Environmental contamination has resulted from mining, smelting and other industrial operations. Mercury can be converted to organic forms by microorganisms in aquatic systems. Industrial mercury emissions were converted to methyl mercury and bio-accumulated in fish eaten by pregnant women in Minamata Bay, Japan in the 1950s. This situation resulted in severe neurotoxicity and infantile cerebral palsy. Harvesting large ocean fish which have bio-accumulated organic mercury has become an important source of human mercury exposure. Other exposure routes include occupational exposures and pesticides and fungicides.
History and exposure of Arsenic.
Arsenic is an abundant element in the earth's crust and exists in organic and inorganic forms. Inorganic chemical forms are the trivalent and pentavalent compounds of which the trivalent form is generally more toxic. Arsenic is also a known carcinogen. Arsenic has been recognized for centuries due to its toxic properties and has been used in pesticides and fungicides. Arsenic readily passes the placenta and is especially toxic to the fetus. Acute ingestion of inorganic arsenic can affect all major organs with progression to severe gastrointestinal injury, shock, and death. Other forms of toxicity include a sensorimotor peripheral neuropathy affecting the lower ends of all extremities (glove and stocking effect). Lower level chronic exposures affect most organ systems, especially the hematopoietic system, with resulting bone marrow depression. The predominant sources of human exposure include food, especially seafood, and water. Exposure to pesticides or industrial and mining wastes can be a concern for some communities.
Chrome, in the +VI valence state is a ____________.
Chrome, in the +VI valence state is a carcinogen.
What diseases can manganese toxicity cause?
Manganese toxicity can result in a permanent neurological disorder with symptoms similar to those of Parkinson's disease, including tremors, difficulty walking, and facial muscle spasms.
Exposure and diseases caused by cadmium toxicity.
Cadmium may be found typically in small concentrations in soil but can also be a contaminant of mining operations. Tobacco smoke is a source of cadmium and may be the largest source of exposure for many people. Historically, exposure was possible from food containers and pottery with cadmium-containing glazes. Inhalation of cadmium in sufficient quantities can be toxic to the lungs. Ingested cadmium can be toxic to the kidneys. Accidental exposure to larger quantities of cadmium may cause gastrointestinal upset.
History and exposure of volatile organic compounds (VOCs).
The volatile organic compounds (VOCs) are so-named because they are short-chain or cyclic hydrocarbon compounds which are easily vaporized at ambient temperatures. These substances have become ubiquitous in the human environment since they are commonly used in many chemical products. VOCs are frequently found in adhesives used in building products such as fiberboard, carpeting, resins of furniture, and home products. Their ubiquitous presence has resulted in being a common waste product that has contaminated drinking water. Trichloroethylene (TCE) has become one of the most common contaminants of drinking water supplies because of its widespread use in industry. VOCs have been a common substance for exposures in the workplace, often as degreasing agents and solvents. Occupational exposures may occur via inhalation or dermal absorption. Skin absorption may be rapid due to the lipophilic nature of the degreasers. Once in the body, solvents affect the central and peripheral nervous system, liver, kidneys and hematopoietic system. Some solvents with exposure of historic public health significance include benzene, n-hexane, and fluorochlorocarbons called freons. Benzene has been strongly associated with bone marrow depression and acute mylogeneous leukemia. N-hexane is a cause of peripheral neuropathy in workers. Several solvents, including the special class of freons, have been associated with cardiac sensitization for arrhythmias. TCE is also considered a probable human carcinogen.
History and exposure of pesticides.
Pesticides are toxic compounds intended for the control of insects and have become common contaminants of the human environment. Many of these substances are available as commercial products for use in the home, while some substances, with higher toxicity, are intended for specialized uses by trained applicators. Unfortunately, unintentional human exposure to the pesticides with higher toxicity still occurs. Exposed populations include production workers, applicators, and the general public due to accidental or purposeful exposures; children are especially susceptible to accidental ingestion.
Chemically produced pesticides generally occur in three groupings:
Chemically produced pesticides generally occur in three groupings: organophosphates and carbamates, organochlorines, and pyrethroids.
History and exposure of Persistent Organic Pollutants (POPs)
The title "Persistent Organic Pollutants" is a general term which describes numerous man-made contaminants which are long-lived in the ecosystem and may bio-accumulate in living systems. When absorbed into humans and animals, these pollutants are stored in adipose tissue, especially since endogenous metabolic pathways such as the P450 mechanism often cannot break down POPs. This biological concentration in living systems is called bio- accumulation. This process is important for human exposure from the ingestion of meat or fish with POPs accumulated in fatty tissues.
What is the most toxic Persistent Organic Pollutants (POPs)?
The most toxic of the compounds is 2,3,7,8-tetrachloro-dibenzodioxin.
What do Endocrine Disrupting Compounds (EDC) interfere with?
Endocrine disruptors are exogenous chemical agents capable of interfering with the production, release, transport, metabolism, and elimination of natural hormones.
Exposure and consequences of Endocrine Disrupting Compounds (EDC)
Early studies of the effects of EDCs occurred in wildlife species: For example, municipal effluent containing conjugated estrogens caused feminization of male trout; and exposures to DDT, dioxins, PCBs and pesticides resulted in eggshell thinning and brain asymmetry in the American bald eagle. EDCs can interact with many target tissues and are particularly vulnerable in the developmental life stages. Both the estrogenic and androgenic components of the endocrine system can be affected. Examples of xeno-estrogenic compounds include Diethylstilboestrol (DES); estradiol, some pesticides, and anti-estrogenic compounds such as Tamoxifen. Disruptors of the androgenic pathway include DDE and phthalates. EDCs such as PCBs and PBBs may also affect thyroid system functioning. Increasing concern exists regarding the extent of thyroid deregulation caused by these compounds and specifically the contribution of these environmental agents to cognitive dysfunction, diabetes, and obesity.
Exposure and consequences of Nitrates and Nitrites
Nitrogen containing contaminants are common in US water systems. They are especially common in agricultural areas due to the use of nitrogen-based fertilizers and proximity to animal handling facilities. Nitrates in surface water sources can stimulate algae growth which ultimately increases the biochemical oxygen demand (BOD) and depletion of dissolved oxygen. This increased biochemical oxygen demand (BOD) can have a significant ecologic impact. Nitrites can have important health effects in a sub-population of people with homozygous recessive NADH methemoglobin reductase, and nitrates, while not directly being toxic, can be converted into nitrites by bacteria in the gut. Nitrites convert the iron in hemoglobin resulting in methemoglobin (from the Fe2+ state to Fe3+) which is incapable of carrying oxygen. Infants are especially susceptible to this condition.
What pollutants cause smog?
Smog in modern large cities is usually the result of irradiation of automobile emissions, nitrogen dioxide and ozone and may include other industrial hydrocarbons and pollutants.
What causes ozone?
Ozone is a secondary pollutant formed by the interaction of sunlight with VOCs.
Outdoor Air pollutants: history and exposure
Air emissions in the United States are currently regulated by the Clean Air Act of 1970, as amended, which is enforced by the U.S. Environmental Protection Agency. Several air pollutants, which have been recognized to have adverse public health effects, are regulated. Several significant public health events related to air pollution "smog" have been observed. Excess morbidity and mortality of these events were insidious and not completely recognized until after the event when the statistics for deaths and hospital visits were summarized. The 1948 smog inversion in Denora, Pennsylvania and the 1952 smog in London, England were two such events. These events are the extreme versions of sulfur smog events resulting from combustion, usually coal. More modern air events have been related to exhaust emissions from automobiles.
The National Ambient Air Quality Standards (NAAQS) include which 6 primary air pollutants?
The National Ambient Air Quality Standards (NAAQS) include primary air pollutants; carbon monoxide, sulfur dioxide, nitrogen dioxide, particulates, ozone, and lead.
Carbon monoxide
Carbon monoxide acts by reducing oxygen delivery to body tissues, especially the brain and heart. The health effects are most serious for those who have pre-existing cardiovascular conditions. Adverse central nervous effects, such as vision difficulties, reduced cognition and manual dexterity, and difficulty in performing complex tasks have been reported in healthy people.
Sulfur dioxide
Sulfur dioxide has been related to various adverse respiratory effects including bronchoconstriction and increased asthma symptoms. Studies have demonstrated a relationship between short-term exposure and increased visits to emergency departments and hospital admissions for respiratory illnesses, particularly in at-risk populations including children, the elderly, and asthmatics.
Nitrogen dioxide
Nitrogen dioxide has been linked to adverse respiratory effects including airway inflammation in healthy people and increased respiratory symptoms in people with asthma even with short term exposures. Studies have demonstrated a relationship between short-term inhalation of NO2 and increased visits to emergency departments and hospital admissions for respiratory issues, especially asthma.
Ozone
Ozone has been demonstrated to cause airway irritation, coughing and difficulty breathing. Wheezing may occur especially among asthmatics during exercise or other outdoor activities. Aggravation of asthma and an increased susceptibility to other respiratory diseases may occur. Also, ozone, at ground level, is a primary constituent of smog and is associated with increase rates of respiratory fatalities. Ozone is a secondary pollutant formed when nitrogen oxides (NOx), carbon monoxide (CO) and volatile organic compounds (VOCs) react in the atmosphere in the presence of sunlight.
Particulates
Particulates have been a recent contaminant of special concern. When introduced as a NAAQS pollutant, air particulates were measured as total suspended particulates (TSP) and later as those less than 10µ in diameter. Due to concerns about the greater adverse health effects of smaller particulates, EPA now requires testing for particulates less than 10µ in diameter and those less than 2.5µ in diameter (fine particulates). The fine particulates can enter the respiratory bronchioles and alveoli. Increased respiratory irritation can result in coughing, shortness of breath, decreased lung function and exacerbation of asthma. The fine particulates have been associated with an increase in premature deaths, especially from heart attacks and strokes.
Indoor Air Pollutants
The quality of indoor air has become a significant public health concern due to the increasing concentrations of airborne contaminants, the contained nature of modern structures, and the large amount of time spent indoors. There are many sources of indoor air contaminants including combustion products, chemicals such as cleaning products, personal grooming materials, or indoor propellants, off-gassing of solvents from construction materials, fabrics, and furniture, biological materials such as pet dander, insects, molds, and bacteria. In addition, other potentially dangerous contaminants may occur in some conditions such as the infiltration of radon and the migration of outdoor contaminants.
Environmental Tobacco Smoke and Combustion Products
Combustion products continue to be a significant contaminant of indoor air. This problem is being addressed, in some instances, through the modernization of forced air heating and ventilation systems. Some sources, such as indoor fire places remain in many homes; and worldwide indoor combustion from cooking and heating sources remains a significant exposure source. WHO considers indoor combustion of heating and cooking materials a major global health problem. Indoor tobacco smoke continues to be a major contributor to the adverse quality of indoor air. Second hand smoke, which is the inhalation of the non-inhaled portion of the smoke side stream, contains significant concentrations of many contaminants including several carcinogenic polycyclic aromatic hydrocarbons, and heavy metals. Children seem to be especially susceptible to the effects of second hand smoke with an increased prevalence of asthma, otitis media, lung infections, and other respiratory diseases. An increased incidence of sudden infant death syndrome (SIDS) has also been associated with second hand smoke exposure.
Insects
Dust mite (Dermatophagoides) and cockroach allergens are present on surfaces, especially soft surfaces such as carpeting, mattresses, pillows, and fabric covered furniture. The allergens become airborne when disturbed. These insect allergens are related to the degree of infestation and are demonstrated frequently in warm and moist environments. They have been demonstrated in inner-city living environments. Exposures have been associated with more days of wheezing, missed days of school, and more emergency department visits and hospitalizations.
Indoor Mold
Species of common indoor molds, such as Aspergillus, Penicillium, and Cladosporium, are found in humid household living environments such as basements, crawlspaces, or bathrooms. Poorly maintained buildings, with rainwater leakage, can have mold problems. Also, homes with weather damage developed extremely high mold concentrations as was observed in Louisiana and Mississippi flood damage after hurricanes Katrina and Rita. Many mold species are known allergens and may exacerbate asthma, particularly in children. . In 2004, the Institute of Medicine issued a report "Damp Indoor Spaces and Health". The report concluded that sufficient evidence exists "of an association between damp indoor environments and some upper respiratory tract symptoms, cough, wheeze, and asthma symptoms in sensitized persons". The report also includes a series of transdisciplinary recommendations for engineers, architects, and environmental health professionals.
Radon
Radon is the second leading cause of death from lung cancer. The gas is generated in the normal radioactive decay of small levels of uranium, in the earth's crust, to the final radioactively stable element, lead. Geographic areas with greater concentrations of granite rock have an increased risk for radon exposure. The physical state of radon is as a gas which easily diffuses into living areas from the soil and is also inhaled into the lungs. Radon can also be dissolved in ground water. The continued decay of radon into other radioactive substances, collectively called radon daughters, return the physical state back into a solid. Both radon and several of the radon daughters decay via the release of alpha particles which are especially carcinogenic if near lung bronchial cells. A 2003 EPA assessment of risk of radon in homes estimated approximately 21,000 lung cancer deaths per year. Radon exposure can be prevented and inexpensive toolkits exist to measure radon in the air and water.
Radiation
The toxic properties of radiation relates to the ability to generate changes in molecular structures due to the direct physical changes in nuclear material or to their ability to excite the nuclear components or electrons and enhance their reactivity. These changes in components of cells results in a loss of function or death or in changes in genetic material with resulting inheritable defects. These defects may lead to inheritable reproductive changes or to the production of an aberrant cell line and carcinogenic pathology. The carcinogenic potential is well recognized with ionizing radiation, but the evidence is less strong for non-ionizing radiation. One example is the association of ultraviolet light with skin cancer.
Light in the ultraviolet range has shorter wave lengths categorized into three spectra:
Light in the ultraviolet range has shorter wave lengths categorized into three spectra: 320 to 400 nm called UV-A, 290-320 nm UV-B, and less than 290 nm UV-C.
Which wavelength causes sunburns
UV-B is the predominant wave length range which causes "sunburn."
Electrical and magnetic fields
Electrical and magnetic fields are invisible gravitational forces created by the electrical charges of high voltage sources such as power lines, electrical appliances and other electric equipment. These waves are very long, measured in meters. Concern has been raised for other sources of frequent human contact such as cellular telephones, computer terminals, electric blankets, microwave ovens and many other devices. The toxic effect is theorized to relate to the activation, and heating, of water molecules at the cellular level. Some epidemiologic evidence suggests associations with breast cancer in men, adult leukemia, and adult brain cancer. The National Toxicology Program of the National Institute of Environmental Health Sciences is planning expanded studies on the radio frequency radiation emitted by cellular phones, but currently they report that "the weight of scientific evidence has not conclusively linked cell phones with any health problems."
Noise
Noise as a physical agent continues to be a significant occupational hazard. Although some studies suggest an association between lower, constant noise levels and cardiovascular disease, noise induced hearing loss is the main toxic effect. Noise generates a neurosensory change in the receptors of the inner ear. High, but short term, exposures can generate a temporary decrease in the hearing threshold, but both very loud and chronic noise exposure can generate permanent changes. Noise is measured in several ways, but the measure for regulatory purposes regulated by the Occupational Safety and Health Administration (OSHA) are intensity, measured as decibels, by the A scale.
What is the main social consequence of hearing impairment?
The main social consequence of hearing impairment is the inability to understand speech in normal conditions, which is considered a social handicap.
Particles and Pathologic Mechanisms
Ionizing radiation results from the release of atomic material or energy due to instability of the atomic structure. Some radiation comes from natural sources, such as that from cosmic rays and radioactive substances in the earth's crust. The gray (Gy) is the current official unit of measure for radiation exposure, but references to rads and rems are still used; a gray is equal to 100 rad. People are exposed to this "background" radiation at a rate of about 1 to 2 mGy per year. There are three types of radiation particulates: alpha particles, which consist of a hydrogen nucleus, a beta particle which consists of an electron or positron, and a neutron. The additional types of radiation are x-rays and gamma rays. The alpha particle is a relatively large mass unit which has, due to its size and lower energy, a low ability to penetrate tissue. External alpha sources cannot penetrate the dead keratin epithelial layer of the skin but are extremely toxic to the susceptible tissue such as occurs when the radioactive substance is taken internally, via ingestion or inhalation. Beta radiation has greater penetration but generate relatively less damage per particle. Likewise, gamma and x-rays have very high penetration, and a high energy level. When the relative biological effect of the individual types of radiation is considered, the biological radiation effective dose is measured as rems (Roentgen Equivalent Man). Since DNA is one of the most sensitive targets of radiation exposure, cancer is an important effect. Cancers of the lung, breast, bone, brain, hematopoietic system (leukemia and lymphoma), skin, and thyroid have all been associated with radiation exposure. Important epidemiologic associations between exposure to radiation and cancer have been identified in Japanese atomic bomb survivors for leukemia and breast cancer, uranium miners and lung cancer, and patients treated with radiation to the thymus and thyroid cancer. In addition to cancers and other conditions due to chronic exposures, acute radiation illnesses may be seen in occupational disasters. Acute radiation illness may begin after an exposure in excess of 1Gy (100 rad) and is always expected with exposures in excess of 4Gy. The three main organ systems affected are the gastrointestinal, hematopoietic and neurological system.
What is Ionizing radiation a result of?
Ionizing radiation results from the release of atomic material or energy due to instability of the atomic structure.
In the context of the risk assessment process, what is a hazard defined as?
In the context of the risk assessment process, a hazard is defined as "a factor or exposure that may adversely affect health."
What is risk and how is it expressed?
Risk is described as the probability that an event will occur and is expressed in many ways: voluntary/assumed versus involuntary/imposed; real versus perceived; absolute versus relative; total versus incremental.
What is zero risk?
Zero risk requires a complete elimination of a hazard, which is often not practical. Individuals or society via laws and policies may determine that some benefits are worth the risk, but the feasibility of eliminating all risk may not be realistic in the context of limited resources.
How is acceptable risk defined by the Clean Air Act?
While environmental regulations do not specify a true "acceptable standard", acceptable risk is expressed in terminology such as "ample margin of safety", and "lowest achievable emission rate (Clean Air Act).
What is "de minimis" risk?
Some policies use the concept of "de minimis "risk, determining that a given risk is so small that is it acceptable. A risk of 1 in a million is accepted as a threshold. A Supreme Court decision related to benzene considered the range between 1/10000 and 1/1,000,000 a gray area, influenced by other factors such as potency and susceptibility.
What is risk assessment?
Risk assessment is defined as "a qualitative/quantitative scientific process conducted to characterize the nature and magnitude of potential risks to public health from exposures to hazardous substances, pollutants or contaminants".
What is Risk management?
Risk management involves the judgment and analysis that combine the scientific results of a risk assessment with economic, political, legal, and social factors to produce a decision about environmental action.
What is Risk communication?
Risk communication refers to the interactive exchange of risk assessment and management information and opinions with communities, governmental officials, and the media.
What are the 4 risk assessment components?
The risk assessment process consists of four components: hazard identification, dose-response evaluation, exposure assessment, and risk characterization.
Risk assessors use a _________ ____________to review and analyze toxicity data, weigh the evidence that a substance causes adverse effects, and evaluate whether toxic effects in one setting are likely to occur in another setting.
Risk assessors use a qualitative approach to review and analyze toxicity data, weigh the evidence that a substance causes adverse effects, and evaluate whether toxic effects in one setting are likely to occur in another setting.
What are the primary purposes of the hazard identification step?
The primary purposes of the hazard identification step are to identify contaminants and exposures which may cause a health hazard and screen for and identify contaminants of concern to be evaluated further.
What are the sources of toxicity data?
Sources of toxicity data are derived from both human and animal studies. Human studies include case reports and epidemiologic studies. Animal studies include general toxicity studies to determine how duration of exposure influences toxicity, and specialized, target organ specific studies.
What approach is used to categorize the hazard posed by carcinogens?
A weight-of-evidence approach is used to categorize the hazard posed by carcinogens. Based on available human and animal data, risk assessors determine whether the evidence is sufficient, limited, or inadequate, or whether no data are available to assess the evidence. Lastly, they might decide that there is no evidence to suggest that a particular chemical may cause a carcinogenic effect
The International Agency for Research on Cancer (IARC) classification of cancer agents.
IARC's classification is widely used to determine the cancer risk of newly introduced compounds.
Non-Cancer risk assessments focus on __________ ___________ and are conducted to determine the effect of a specific toxicant on the target organ, or a specific disease endpoint (kidney, liver, lung etc).
Non-Cancer risk assessments focus on systemic toxicity and are conducted to determine the effect of a specific toxicant on the target organ, or a specific disease endpoint (kidney, liver, lung etc).
What is a dose-response evaluation?
A dose-response evaluation is an attempt to quantitatively determine the relationship between exposure to a toxicant and disease. These assessments rely heavily on mathematical models such as the cancer linear multistage model.
What do Exposure assessment involve?
Exposure assessment involves the development of a quantitative estimate of the magnitude, duration, frequency, and timing of an exposure to the toxicant of concern. Integral to assessing exposures in the context of risk assessments is ascertaining the target organs or tissues, the scenario-specific exposure pathway, and the manner in which exposure occurs ( for example, single versus lifetime duration of exposure).
T/F: Risk characterization integrates the first three components of the risk assessment to ultimately calculate the risk.
True
Risk characterization integrates the first three components of the risk assessment to ultimately calculate the risk.
Carcinogenic risk assessments use ________ models.
Carcinogenic risk assessments use probabilistic models.
Non-carcinogenic risk assessments employ _______ ___________ such as US EPA's Reference Dose; ATSDR's Minimal Risk Level, and the ACGIH Threshold Limit Value.
Non-carcinogenic risk assessments employ reference levels such as US EPA's Reference Dose; ATSDR's Minimal Risk Level, and the ACGIH Threshold Limit Value.
How is Non-carcinogenic risk calculated?
Non-carcinogenic risk is calculated in its simplest form using the following formula:

MRL= [NOAEL/UFxMF)

where the uncertainty factors (UF) are used to account for the extrapolation from animals to humans, for inter human variability, or for uncertainty when a LOAEL (lowest observed adverse effect level) is used in place of a NOAEL.
What is the challenge once a risk assessment is completed?
Once a risk assessment is completed the challenge becomes how to use this information to make risk management decisions and how to communicate the often complex findings to stakeholders with widely varying interests.
What are local health agencies responsible for?
Local health agencies are responsible for many community services that aid in protecting the public from infectious and hazardous agents through environmental sanitation programs. These programs have traditionally included restaurant and food service inspections, review of sanitary sewage disposal including septic systems, rodent and animal control, and water hygiene. In recent years, housing safety, recreational water facility inspections, hotel inspections and many other community facilities have come under the purview of local health agencies.
The Centers for Disease control reports an estimated ____ million cases of foodborne illness occur each year in the United States.
The Centers for Disease control reports an estimated 76 million cases of foodborne illness occur each year in the United States.
What are the most common types of foodborne infections?
CDC reports that the most commonly recognized foodborne infections are those caused by the bacteria Campylobacter, Salmonella, and E. coli O157:H7, and by a group of viruses called calicivirus, also known as the Norwalk and Norwalk-like viruses.
T/F: Food protection is an extensive activity that involves federal, state and local agencies.
True
Food protection is an extensive activity that involves federal, state and local agencies.
How is food contaminated?
Food may be contaminated by toxins, agricultural chemicals, and pharmaceuticals, in addition to pathogens. Therefore, concern for food must be considered from the field or farm, through processing, and to preparation, cooking and storage at the serving location.
Temperature control continues to be a mainstay prevention activity. Maintaining raw foods at temperatures below ____°F, or prepared food at or above ___°F is required.
Temperature control continues to be a mainstay prevention activity. Maintaining raw foods at temperatures below 41°F, or prepared food at or above 140°F is required.
Where does drinking water typically come from?
Drinking water is typically obtained from surface lakes, reservoirs or rivers or from groundwater wells.
T/F: All surface water requires further treatment.
True
All surface water requires further treatment.
What are the 4 stages of water treatment?
The four stages of water treatment are flocculation, sedimentation, filtration and disinfection.
What is a common by-product of water disinfection?
A common by-product of disinfection is a group of chemicals called trihalomethanes (THMs) and halo-acetic acids (HAAs); the levels of these contaminants depends on disinfection technology, dose of applied disinfectant, and concentration of organic matter.
Why is proper sewage treatment important?
The proper treatment of sewage is important, not only as an esthetic issue, but to prevent contamination of food and water and to reduce the environmental impact of returning large quantities of biological waste into the environment.
What is the Five-day biochemical oxygen demand?
The Five-day biochemical oxygen demand (BOD, or BOD5), is measured by the quantity of oxygen consumed by microorganisms during a five-day period, and is the most common measure of the amount of biodegradable organic material in, or strength of, sewage. However, there is a large amount of variability in the BOD measurement within samples.
T/F: Total Organic Carbon (TOC) and Chemical Oxygen Demand (COD) will also be used to measure the strength of sewage influent and effluent.
True
Total Organic Carbon (TOC) and Chemical Oxygen Demand (COD) will also be used to measure the strength of sewage influent and effluent.
T/F: All sewage is not the same, because the contributors are not the same.
True
All sewage is not the same, because the contributors are not the same.
What is the primary treatment for sewage?
The 'primary treatment' involves the separation of course objects removed by a screen, heavy solids from liquids, and removal of fats, oil, and grease (FOG).
What is the secondary treatment for sewage?
The 'secondary treatment' is the digestion of the sewage by microorganisms; this occurs in a large basin in which excess oxygen is diffused into the mixed liquor. The next step of treatment is a physical removal step where the microbes and larger particulates are allowed to flocculate and settle in a clarifier.
What is the tertiary treatment for sewage?
The effluent can then be treated by tertiary processes (for example, to remove nitrogen or phosphorus) or disinfected and discharged to a receiving water (currently practiced by New Orleans).
Municipal effluent is disinfected prior to discharge to reduce the pathogen load, usually by ___________, but any technology used for drinking water can be applied.
Municipal effluent is disinfected prior to discharge to reduce the pathogen load, usually by chlorination, but any technology used for drinking water can be applied.
Where is waste sludge from the primary and secondary treatment processes deposited?
Waste sludge from the primary and secondary treatment processes, after dewatering, is usually deposited in landfills, incinerated, or further disinfected and applied to land as a soil-amender, or processed to generate other value-added products such as fertilizers.
Homes not on central sewer usual use ______ _________. These systems collect wastewater in large underground tanks, and anaerobic bacteria degrade the waste matter.
Homes not on central sewer usual use septic systems. These systems collect wastewater in large underground tanks, and anaerobic bacteria degrade the waste matter.
Solid waste is regulated under the ________ _________ and _______ Act (later amended as The Hazardous and Solid Waste Amendments of 1984) and categorizes waste as hazardous and non-hazardous.
Solid waste is regulated under the Resource Conservation and Recovery Act (later amended as The Hazardous and Solid Waste Amendments of 1984) and categorizes waste as hazardous and non-hazardous.
What level of government manages non-hazardous waste?
Managing non-hazardous waste is delegated to the states and typically managed at the local level.
T/F: The use of poorly designed and constructed landfills, especially for disposing chemical and hazardous waste, has had large public health implications.
True
The use of poorly designed and constructed landfills, especially for disposing chemical and hazardous waste, has had large public health implications.
Give an example of a large public health disaster following improper hazardous waste disposal
A famous example of improper disposal of hazardous waste is the Love Canal landfill near Niagara Falls, NY, which was a partially constructed canal converted to a depository for chemical waste. Waste materials migrated from the original 'landfill' to the surface and into homes and a school and created widespread human exposure to hazardous substances.
Many pathologic conditions may result from exposures to hazardous substances in the _______ and _________.
Many pathologic conditions may result from exposures to hazardous substances in the workplace and environment.
Environmental factors are also responsible for safety hazards resulting in injuries, as well as orthopedic repetitive motion and musculoskeletal injuries, especially ______ ________.
Environmental factors are also responsible for safety hazards resulting in injuries, as well as orthopedic repetitive motion and musculoskeletal injuries, especially back injuries.
Other significant organ systems affected by workplace exposures include the _____, ________ _______, _______ _____, ________ _______, and the _____ and ________ ____________.
Other significant organ systems affected by workplace exposures include the skin, respiratory system, cardiovascular system, hematopoietic system, and the brain and neurological system.
T/F: Toxicities can include adverse effects on the reproductive system resulting in birth defects and premature deliveries. Cancer is also an adverse health effect resulting from exposures to hazardous substances.
True
Toxicities can include adverse effects on the reproductive system resulting in birth defects and premature deliveries.Cancer is also an adverse health effect resulting from exposures to hazardous substances.
Give historic examples of diseases caused by exposure to hazardous substances.
Two important historic examples include acute myelogenous leukemia (AML) resulting from exposure to benzene, liver cancer from exposure to vinyl chloride monomer, and bladder cancer from exposure to aniline dyes.
Name three significant exposures with historic significance to workers
Three significant exposures with historic significance to workers include inhalation of asbestos and silica as well as mixed dust exposure in coal miners.
What is Asbestos?
Asbestos is an iron and magnesium containing non-crystalline silicate which has a characteristic fibrous physical state. The fibers may be short and firm or long and filamentous.
When and who were the first studies of asbestos done on?
Although cases of lung disease and cancer have been reported from the early part of the twentieth century, the first large studies were among shipyard workers exposed to chrysotile (historically called white) asbestos. These studies identified plural thickening and scarring, typically reported in the lower plural surfaces near the diaphragm and in the abdomen, scarring of the lung tissue or interstitial fibrosis (asbestosis) which is usually seen in the lower lung fields and two forms of cancer, bronchogenic carcinoma and mesothelioma, to be strongly associated with asbestos exposure.
What is silicosis and who does it effect primarily?
Silicosis is an inflammatory lung disease caused by the inhalation of crystalline silica and has been historically reported among miners, quarry and stoneworkers, sandblasters and many other professions.
What is Coal workers' pneumoconiosis?
Coal workers' pneumoconiosis, also called black lung, is a chronic obstructive lung disease among miners. The obstructive symptoms are due to chronic inflammation from dust inhalation creating bronchitis.
Exposures to environmental hazards in communities may be equally diverse, but they are frequently more difficult to document an _____-_______ relationship.
Exposures to environmental hazards in communities may be equally diverse, but they are frequently more difficult to document an exposure-response relationship.
What is one important community based disease in the US?
One important community based disease in the US is asthma.
What is asthma?
Asthma is a chronic respiratory disease characterized by airway inflammation and episodes of hyper-reactive airways with reversible airway obstruction. The etiology of asthma is complex with both genetic and environmental risk factors.
What environmental triggers have been identified to exacerbate asthma?
Many environmental triggers have been identified including specific allergens, like pollen, mold, and dust mites, as well as non-specific odors and irritants, such as perfumes. Tobacco smoke, insect allergens such as dust mites and cockroaches, animal dander including rodents, molds, formaldehyde, and volatile chemicals have been reported as important indoor substances associated with exacerbations of asthma. Episodes of enhanced outdoor air pollution have also been associated with asthma exacerbations.
What is a historic compound associated with occupational asthma?
A historic compound associated with occupational asthma is toluene di-isocyanate, which may have a pharmacological mechanism to its causation of asthma.
T/F: There is an increasing body of evidence which indicates that neither environmental factors nor genetic factors alone result in increased susceptibility to toxicants but rather the interaction of the two.
True
There is an increasing body of evidence which indicates that neither environmental factors nor genetic factors alone result in increased susceptibility but rather the interaction of the two.
T/F: Environmental health disparities research links intrinsic and extrinsic factors to develop sustainable, community-based interventions.
True
Environmental health disparities research links intrinsic and extrinsic factors to develop sustainable, community-based interventions.
T/F: The Federal Meat Inspection Act of 1920 provided a federal role for meat inspection.
False
The Federal Meat Inspection Act of 1906 provided a federal role for meat inspection.
T/F: The Federal Food, Drug, and Cosmetic Act of 1938 defined what constitutes food, food additives such as food colorings, drugs, medical devices, and dietary supplements. This legislation has had numerous amendments addressing such issues as infant formulas, food marketing, controlled substances, and animal food and pharmaceuticals.
True
he Federal Food, Drug, and Cosmetic Act of 1938 defined what constitutes food, food additives such as food colorings, drugs, medical devices, and dietary supplements. This legislation has had numerous amendments addressing such issues as infant formulas, food marketing, controlled substances, and animal food and pharmaceuticals.
In addition to the Food and Drug Act with amendments, numerous other pieces of legislation have been passed which address specific food or medication types, packaging and distribution, nutrition, and food protection from other contamination sources, such as the _________ __________ of 2002.
In addition to the Food and Drug Act with amendments, numerous other pieces of legislation have been passed which address specific food or medication types, packaging and distribution, nutrition, and food protection from other contamination sources, such as the Bioterrorism Act of 2002.
What is the principal law which addresses health in the workplace?
The principal law which addresses health in the workplace is the Occupational Safety and Health Act of 1970.
What did the Occupational Safety and Health Act of 1970 create?
This legislation created the regulatory agency the Occupational Safety and Health Administration (OSHA), under the Department of Labor, and the National Institute for Occupational Safety and Health (NIOSH), a health investigation and research agency. OSHA establishes regulatory exposure levels, called Permissible Exposure Limits (PELs), and has regulatory inspection authority to help assure a safe and healthy workplace.
What does National Institute for Occupational Safety and Health (NIOSH) do?
NIOSH conducts non-regulatory health hazard evaluations, conducts epidemiology, industrial hygiene and toxicological research and develops recommended exposure limits (RELs). NIOSH also conducts research in worker safety, occupational lung disease and respiratory protection, and currently has regulatory responsibilities for mine safety and health.
What act is the general overall foundation for organized environmental policy in the US?
The general overall foundation for organized environmental policy in the United States is the National Environmental Policy Act (NEPA).
What is the main purpose of National Environmental Policy Act (NEPA)?
The main focus of the law was to set national policy on protecting the general environment. It minimized adverse environmental and ecologic impact and required the development of environmental impact statements (EIS) which review the potential adverse ecologic effects of many construction and land use activities. EIS statements can address public health issues.
What was the first federal air legislation and what did it do?
The first federal air legislation began with the Air Pollution Control Act of 1955. This legislation did not provide regulations, but it initiated the study of the degree and sources of air pollution.
What did the The 1970 Clean Air Act accomplish?
The 1970 Clean Air Act authorized the establishment of National Ambient Air Quality Standards (NAAQS) and the establishment of National Emission Standards for Hazardous Air Pollutants (NESHAPs). NAAQS were established for lead, ozone, nitrogen dioxide, sulfur dioxide, carbon monoxide and particulates (toxic effects are discussed in the section on air pollutants.)
What did the Clean Air Act Amendments of 1977 address?
The Clean Air Act Amendments of 1977 addressed control measures including the definition of attainment areas.
What did the 1990 Amendments to the Clean Air act of 1970 authorize?
In 1990, the Amendments to the Clean Air act of 1970 authorized a program to control 189 toxic pollutants, including those previously regulated by the National Emission Standards for Hazardous Air Pollutants.
What are come laws that regulate water pollution?
There have been several Federal laws that regulate water pollution beginning with the first environmental law, the Rivers and Harbors Act of 1899. Other laws include the Protection of Coastal Areas Act in 1972, the Water Pollution Act of 1972, the Ocean Dumping Act of 1972, and the Water Quality Act of 1987.
What two laws with major public health implications deal with drinking water?
The two laws with major public health implications are the Clean Water Act of 1977 and the Safe Drinking Water Act of 1974.
What did the the Clean Water Act of 1977 do?
The clean water act was passed to protect the environmental quality of water. This passage had secondary implications to public health since most drinking water is derived from surface water sources.
What did the Safe Drinking Water Act of 1974 do?
The Safe Drinking Water Act required the routine testing of public drinking water supplies; it went into effect in 1977 and was later amended in 1996. Primary drinking water standards include microorganisms, inorganic contaminants, organic contaminants, disinfectants, disinfection byproducts, and radionuclides. An extensive list of non-regulated pollutants is also provided as secondary drinking water standards.
What was one of the first laws regulating toxic substances and what did it aim to do?
One of the first laws regulating toxic substances was the Federal Insecticide, Fungicide, and Rodenticide Act of 1946. The law regulates the manufacture, distribution, sale and use of pesticides. It requires the regulation of most pesticides and requires the certification of pesticide applicators. The intent was to minimize risks for human exposures and adverse health events.
What did the The Toxic Substance Control Act (TSCA) of 1976 do?
The Toxic Substance Control Act (TSCA) of 1976 defined a toxic substance and allowed for the regulation of chemical substances whose manufacture, distribution, or use may present an unreasonable risk of injury to health or the environment. This law requires manufacturers to notify the Environmental Protection Agency of new chemicals.
T/F: The EPA can require testing, additional information, and can prohibit or limit a chemical's manufacture and use.
True
The EPA can require testing, additional information, and can prohibit or limit a chemical's manufacture and use.
T/F: The TSCA inventory contains more than 83,000 chemicals.
True
The TSCA inventory contains more than 83,000 chemicals.
Give some examples of hazardous chemicals that the Toxic Substance Control Act (TSCA) of 1976 eliminated?
The limitation of hazardous and persistent chemicals was conducted by this legislation including the elimination of polychlorinated biphenyls (PCBs) and lead based paint.
What does the Solid and Hazardous Waste Act of 1976, also known as the Resources Conservation and Recovery Act (RCRA) require?
The Solid and Hazardous Waste Act of 1976, also known as the Resources Conservation and Recovery Act (RCRA) is sometimes referred as the "cradle to grave" law for toxic substances. Under this law, hazardous materials are tracked from manufacture, through use, to final disposal or recycle processing. The manufacturer is the responsible agent and repository for regulatory documentation. The law also regulates "solid" waste, which also includes liquids, underground storage tanks and waste treatment and storage facilities.
What is the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), also know as Superfund?
The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), also know as Superfund, is a federal program to provide regulatory oversight and funding to address uncontrolled hazardous waste sites.The legislation provided for a system of identifying, assessing, and cleaning of sites by the EPA.
Why do some PH agencies like using qualitative risk assessment approaches?
In contrast to a quantitative risk assessment approach used by regulatory agencies, a qualitative, weight-of-evidence approach provides public health officials other opportunities to identify and conduct public health actions in response to an identified hazard. The use of these approaches can be extremely effective when used jointly by regulatory and public health officials in providing effective public health actions and the clean-up of hazardous environmental contamination in a manner that meets regulatory and judicial requirements.
Name two federal public health agencies that use a qualitative health hazard assessment approach.
Two federal public health agencies that use a qualitative health hazard assessment approach are the National Institute for Occupational Safety and Health (NIOSH) of the Centers for Disease Control and Prevention, and the Agency for Toxic Substances and Disease Registry (ATSDR).
What does NIOSH do?
NIOSH conducts Health Hazard Evaluations (HHE) in workplaces when requested by workers or their authorized representatives, such as a labor union, at a specific worksite.
What are Health Hazard Evaluations (HHEs)?
The HHEs include a worksite evaluation by industrial hygienists and may also include medical or epidemiologic studies. The HHE provides a description of the worksite and processes, identifies opportunities for exposure to hazardous substances, usually includes exposure sampling results, and biomarker testing, if conducted.
What does ATSDR do?
ATSDR conducts Public Health Assessments (PHAs) in community settings for all sites on the National Priorities Listing (NPL) or if petitioned by the public.
What are Public Health Assessments (PHAs)?
PHAs evaluate data provided by environmental agencies, usually EPA, and assesses whether a completed human exposure pathway is present. If so, health education, epidemiology and medical studies, and other activities, such as toxicology research may be conducted.
T/F: Both the HHEs and the PHAs provide recommendations for actions that are provided to the public, state health agencies and responsible regulatory agencies, such as OSHA and the EPA, to help them in conducting their regulatory responsibilities.
True
Both the HHEs and the PHAs provide recommendations for actions that are provided to the public, state health agencies and responsible regulatory agencies, such as OSHA and the EPA, to help them in conducting their regulatory responsibilities.
Compare and contrast Health Hazard Evaluations (HHEs) and Public Health Assessments (PHAs).
What do biomarkers of exposure measure?
Biomarkers of exposure measure the level of a specific substance or its metabolite in body fluids or excreta.
T/F: Exposure assessments are a first and important step in characterizing the public health implications of toxicants.
True
Exposure assessments are a first and important step in characterizing the public health implications of toxicants.
Name the other measurements with decreasing level of specificity that measure the level of a specific substance.
a metabolite; an effect of the interaction of the toxicant with the target tissue; indirectly the absorption of the toxicant; and lastly the adverse effect on the target organ.
Following a comprehensive exposure pathway evaluation, environmental health scientists consider several types of ____________ studies.
Following a comprehensive exposure pathway evaluation, environmental health scientists consider several types of epidemiologic studies.
T/F: Because of the difficulty in establishing causal relationships and the inherent limitations associated with most studies, the results of environmental epidemiology studies are challenging to communicate.
True
Because of the difficulty in establishing causal relationships and the inherent limitations associated with most studies, the results of environmental epidemiology studies are challenging to communicate.
Two frequently used applications of environmental epidemiologic studies are ___________ ___________ and ______________.
Two frequently used applications of environmental epidemiologic studies are cluster investigations and surveillance.
What is surveillance, where does its data come from, and what are challenges associated with this type of epidemiologic study?
By definition, surveillance is the systematic, longitudinal collection, analysis and interpretation of health information and the sharing of that information with those who need to know. Data sources for surveillance activities include mortality records; cancer-, birth defects-, and hospital-based disease registries; hospital discharge data; and longitudinal cohort studies. Challenges associated with implementing surveillance activities include the absence of an ongoing data collection system for the outcome of interest; statistical difficulties (low power); lack of consistency of detection methods; and high costs.
What are Registries?
Registries are an example of special surveillance systems using a very structured system of data collection.
T/F: Environmental health education is an integral component of any community environmental health investigation.
True
Environmental health education is an integral component of any community environmental health investigation.
What do many health education activities begin with and what do they lead to?
Many health education activities begin with a systematic conduct of a needs/asset assessment. The needs assessment assists in delineating the target audiences, the educational content, and the desired intervention. The result of that assessment is the foundation of the educational intervention. As part of the intervention, both short term (up to 6 months) and long term (longer than 6 months) evaluations are conducted.
What do Evaluations focus on?
Evaluations focused on shorter term outcomes are targeting increased awareness and knowledge; longer term evaluations are geared to ascertaining sustained behavioral change.
What is one important aspect of community health education?
One important aspect of community health education in conjunction with health studies is to assure communities are aware of the limitations of health studies and the difference between epidemiologic associations and causality.
T/F: Exposures to lesser known hazardous substances or contaminants not previously identified in the most hazardous category or for which the likelihood of exposure was determined to be low may result in the conduct of more detailed toxicological research or the systematic summary of available toxicology information.
True
Exposures to lesser known hazardous substances or contaminants not previously identified in the most hazardous category or for which the likelihood of exposure was determined to be low may result in the conduct of more detailed toxicological research or the systematic summary of available toxicology information.
Give an example of more detailed toxicological research being conducted on a previously low risk hazardous chemical.
For example, the extensive exposure to the pesticide methyl parathion in seven states resulted in the development of a toxicological profile by ATSDR.
From a public health perspective environmental risks are managed in three tiers: ________, ____________, and __________.
From a public health perspective environmental risks are managed in three tiers: primary, secondary, and tertiary.
What is Primary risk management focused on?
Primary risk management focused on prevention is preferred. From a public health perspective, the development of standards and above all the enforcement of existing policies regulating the release of toxicants in the environment are the some of the most effective ways of managing environmental risk. Other examples include: identifying and replacing hazardous material; changing a production process to reduce emissions; encouraging women of childbearing age to avoid eating mercury contaminated fish.
What is Secondary risk management focused on?
Secondary environmental risk management centers on intervention in both biological and ecosystems to avoid adverse effects. This level of risk management emphasizes proactive intervention to avoid adverse effects to the environment and populations once release of that potential toxicant into the environment has occurred. Examples of secondary prevention include bio-monitoring to determine levels of contaminants in populations, or testing the hazard potential of a chemical in a frequently used consumer product.
What is tertiary risk management focused on?
Control is categorized as tertiary risk management. Actions categorized as tertiary risk management are carried out in circumstances where "harm" has already been done, either to the environment or to humans.

Population-based examples of tertiary prevention include removing lead-based paint from inner-city housing of children with elevated blood lead levels; and the treatment of farmers with early signs of pesticide intoxication.

The National Research Council's "Grey Book" on Science and Decisions: Advancing Risk Assessment published a framework for risk-based decision making. Managing environmental health risk requires considering multiple solution options and addressing issues related to health and environmental benefit of proposed solutions; other factors influencing the feasibility of implementing each option; the justification why a specific solution was selected; how to communicate the decision; and ultimately how to monitor its effectiveness.
T/F: Environmental health policy plays a pivotal role in protecting communities against the adverse effects associated with exposures to hazardous substances.
True
Environmental health policy plays a pivotal role in protecting communities against the adverse effects associated with exposures to hazardous substances.
According to the United Nations Intergovernmental Panel on Climate Change (IPCC), by 2100 the average global temperatures will increase ____-__C; sea level is predicted to rise ___-____ cm; and there will likely be increased variability in the hydrologic cycle, increasing the likelihood for more flooding and drought in different local areas.
According to the United Nations Intergovernmental Panel on Climate Change (IPCC), by 2100 the average global temperatures will increase 1.8-5.8 C; sea level is predicted to rise 9-88 cm; and there will likely be increased variability in the hydrologic cycle, increasing the likelihood for more flooding and drought in different local areas.
T/F: The public health implications of climate change are profound and impact those already vulnerable and at risk of environmental insults and other health disparities.
True
The public health implications of climate change are profound and impact those already vulnerable and at risk of environmental insults and other health disparities.
Which regions/climates are particularly vulnerable to climate change?
According to the IPCC, particularly vulnerable regions are areas with highly endemic climate sensitive diseases such as malaria, areas where there is an observed association between epidemic disease and weather extremes such as El Nino associated increase in the severity of diarrheal diseases, areas at risk from combined public health related effects such as water supply and flooding, and areas with existing socio-economic challenges and limited ability to adapt to the environmental challenges associated with climate change.
What will be some public health effects of climate change?
Climate change affects morbidity and mortality globally. Major adverse effects include an increase in waterborne diseases, exacerbation of greenhouse gases, pollen, and other allergens increasing diseases of the respiratory system such as asthma as well as adverse cardiovascular health conditions, increases in vector-borne diseases both rodent-borne (hanta virus, plague), and vector-borne (malaria, West Nile virus), and food productivity often worsening malnutrition in already socio-economically challenged regions of the world.
What is the public health approach to addressing climate change?
The public health approach to addressing climate change is mitigation as a primary prevention strategy, and adaptation as a secondary strategy. Mitigation efforts are aimed at stabilizing or reducing the production of greenhouse gases through policy and advanced technologies capable of expediting removal. Adaptation strives to lessen the public health impact of climate change by preparing to effective manage the anticipated adverse effect (e.g. floods).
What is the "built environment"?
The built environment represents all aspects of community design including parks, schools, transportation and access to services. Design of the built environment affects health in major ways: ineffective land use stifles opportunities for physical activity thereby increasing the risk of obesity and cardiovascular disease.
What are Health Impact Assessments (HIA) and what are they used for?
Health Impact Assessments (HIA) are increasingly utilized in the US to guide land use decisions and community design from a public health perspective. HIAs have become a powerful tool to maximize the health benefit and minimize the effects on health of proposed land use projects.
What are the steps in implementing a Health Impact Assessments (HIA)?
Steps in implementing an HIA include: screening to determine the usefulness of conducting an HIA for the project in study, scoping to identify the health effects of concern, assessing risks and benefits focused on the target population, making recommendations, reporting the findings, and evaluating how the HIA affected the ultimate decision.
What is a transdisciplinary approach to addressing built environment issues and healthy community design?
A transdisciplinary approach to addressing built environment issues and healthy community design is referred to as Smart Growth.
What are the Smart Growth principles?
Among the Smart Growth principles are mixed land use, walkable neighborhoods, transportation choices, multiple housing opportunities, and community [participation in the decision-making process. Increasingly, populations in localities globally facing the consequences of climate change, strive for sustainable development in planning and land use to promote enduring socially, environmentally, and economically healthy communities.
Define environmental justice
Executive Order 12898 issued by President Bill Clinton defines environmental justice as "the fair treatment and meaningful involvement of all people, regardless of race, ethnicity, culture, income, or education level, with respect to the development, implementation, and enforcement of environmental laws, regulations, and policies".
The International Association of Public Participation developed a spectrum with five progressively higher levels of public participation
What is the next step when a baby has a positive result in the newborn screening?
(A) Follow-up testing to confirm the diagnosis
(B) Evaluation of the specimen handling
(C) Referral to a specialist
(D) Offer of genetic counseling to the family
What is the next step when a baby has a positive result in the newborn screening?
(A) Follow-up testing to confirm the diagnosis
Any positive result in a newborn screening procedure must be supported by additional testing before any other steps are taken.
HAACP is a food safety system employed to:
(A) Detect bacterial contamination in food after it happens
(B) Before they happen, identify and control problems that may cause foodborne illness
(C) Isolate and identify bacterial pathogens from a foodborne illness outbreak
(D) Set temperature limits for food containing eggs
HAACP is a food safety system employed to:
(B) Before they happen, identify and control problems that may cause foodborne illness
Reference: Frumkin, p. 608
Which of the following assays would best reveal whether genetic damage was present in a group of people who were exposed to ionizing radiation when an accidental release occurred at a nuclear power plant?
(A) Comet (or single-cell gel electrophoresis) assay
(B) Ames test for reversion mutations
(C) Increased mutation frequency at the HGPRT locus of hamster cells
(D) None of these assays
Which of the following assays would best reveal whether genetic damage was present in a group of people who were exposed to ionizing radiation when an accidental release occurred at a nuclear power plant?
(A) Comet (or single-cell gel electrophoresis) assay
The comet assay tests for DNA damage, and peripheral blood lymphocytes or other human cells can be collected and tested. The other options test for mutations, not damage, and are not applicable to human testing.
If a chemical that is directly cytotoxic is detoxified by metabolism via the microsomal enzyme system and if the activity of this system correlates with basal metabolic rate, which of the following species is expected to be the most sensitive to the chemical (assuming that all of the animals are given an equivalent dose based on weight)?
(A) Human
(B) Mouse
(C) Rat
(D) Dog
If a chemical that is directly cytotoxic is detoxified by metabolism via the microsomal enzyme system and if the activity of this system correlates with basal metabolic rate, which of the following species would you expect to be most sensitive to the chemical (assuming that all of the animals are given an equivalent dose based on weight?
(B) Mouse
The mouse has the highest metabolic rate.
Phase 2 metabolism usually involves:
(A) Microsomal enzymes
(B) Decrease in the polarity of a chemical
(C) Increase in the toxicity of a chemical
(D) Addition of an endogenous moiety
Phase 2 metabolism usually involves:
(D) Addition of an endogenous moiety
Microsomal enzymes represent phase 1 metabolism. For some chemicals, the toxicity of the chemical is increased.
By what programmatic mechanism does the U.S. Environmental Protection Agency (EPA) work with States to implement Environmental Standards such as NAAQS?
(A) By creating a memorandum of understanding focusing on cost sharing of environmental burdens
(B) By establishing air quality monitoring stations
(C) By using a State Implementation Plan (SIP) approved by the EPA
(D) By funding risk assessment studies that provide a basis for the NAAQS for any criterion pollutant
By what programmatic mechanism does the U.S. Environmental Protection Agency (EPA) work with States to implement Environmental Standards such as NAAQS?
(C) By using a State Implementation Plan (SIP) approved by the EPA
The Constitutional division of powers between the Federal and State governments means that both levels of government must operate on mutual respect, recognizing that cooperation rather than conflict better serves the public interest. The natural continuum of the environment cuts across geopolitical boundaries and rightly elicits the concerns of both Federal and State governments. To avoid or minimize contradictory measures and standards among States, the Federal government provides the umbrella (uniform) guidance and standards for ambient air quality and requires States to participate in the implementation by developing a plan that meets Federal requirements. That plan is known as the SIP and contains a number of air quality control measures.
The objective of the National Environmental Policy Act of 1969 and its equivalent at the State level is:
(A) To subject a proposed major project or action to an environmental review study with a view to understanding the potential environmental effects of such a project or action and considering alternative projects and mitigating measures as appropriate
(B) To ensure that an important industrial project or action is constructed
(C) To ensure that the environment is protected at all cost
(D) To achieve sustainable development while relieving the concerns of communities in which a major project or action will be located
The objective of the National Environmental Policy Act of 1969 and its equivalent at the State level is:
(A) To subject a proposed major project or action to an environmental review study with a view to understanding the potential environmental effects of such a project or action and considering alternative projects and mitigating measures as appropriate
Before the National Environmental Policy Act, there was no requirement for a systematic study of the environmental effects of a proposed project. Thus, projects could be executed with little or no regard to the environmental effects. Poor environmental stewardship was apparent in many cases, for example, in disposal of hazardous waste and groundwater contamination. The significant environmental movement of the 1960s pressured Congress to pass the National Environmental Policy Act to promote developments that are in harmony with environmental protection. This approach is executed by ensuring that the environmental effects of a proposed major Federal action or project are studied, understood, and mitigated as much as possible and that better alternatives to a proposed project are preferred.
Federal environmental laws usually allow States to make parallel environmental laws as long as standards in the latter are:
(A) Higher than Federal standards
(B) In conflict with Federal standards
(C) Same as, or equal to Federal standards
(D) No less stringent than Federal standards
Federal environmental laws usually allow States to make parallel environmental laws as long as standards in the latter are:
(D) No less stringent than Federal standards
The Federal government conducts or funds research to determine appropriate environmental and health standards and then makes those the minimum standards. By not allowing States to set less stringent standards, the environment and public health are better protected.
The Emergency Planning and Community Right to Know Act establishes the State Emergency Response Commissions (SERCs) and the Local Emergency Planning Committees (LEPCs) to develop comprehensive emergency response plans to address releases of extremely hazardous substances (EHSs). Such plans must contain the following information:
(A) Material safety data sheet, monitoring device, and emission gauge
(B) Environmental review process and names of responsible people
(C) Medical personnel, evacuation plan, and first aid kits
(D) Identity of regulated facilities, evacuation plan, medical response, and procedure for notifying people named in the plan as well as the general public that a release has occurred
The Emergency Planning and Community Right to Know Act establishes the State Emergency Response Commissions (SERCs) and the Local Emergency Planning Committees (LEPCs) to develop comprehensive emergency response plans to address releases of extremely hazardous substances (EHSs). Such plans must contain the following information:
(D) Identity of regulated facilities, evacuation plan, medical response, and procedure for notifying people named in the plan as well as the general public that a release has occurred
It is important for the plan to identify the facilities being regulated because you cannot manage what you do not know. Equally important is the procedure for notifying the public and the first responders, including medical personnel, that a release has occurred. This approach contributes to effective risk communication to the stakeholders so that efforts to limit exposure can begin promptly. An evacuation plan is crucial to remove people from the danger zone. The routes, means, and timing of evacuation and the officials in charge must be clearly stated and understood. These are some of the major components of the plan to limit human exposure to the release of EHSs.
Waste management is a key environmental public health issue. Hazardous waste is managed from cradle to g rave under the Federal Resource Conservation and Recovery Act. The Comprehensive Environ mental Response, Compensation, and Liability Act requires the clean-up of hazardous waste dump sites that threaten public health. States have parallel hazardous waste laws and exclusively regulate non-hazardous waste. Incorporated in these regulatory efforts are some waste management programs, of which the following is preferred:
(A) Treatment of biohazards before they are disposed
(B) Waste minimization through reuse, recycling, and investment in renewable energy
(C) Waste disposal in sanitary landfills
(D) Storage of waste in containers buried within impervious geological formations
Waste management is a key environmental public health issue. Hazardous waste is managed from cradle to grave under the Federal Resource Conservation and Recovery Act. The Comprehensive Environmental Response, Compensation, and Liability Act requires the clean-up of hazardous waste dump sites that threaten public health. States have parallel hazardous waste laws and exclusively regulate non-hazardous waste. Incorporated in these regulatory efforts are some waste management programs, of which the following is preferred:
(B) Waste minimization through reuse, recycling, and investment in renewable energy
It is best to avoid waste generation. Waste is, for the most part, a byproduct of human economic activities. Therefore, waste generation is inevitable in many instances. However, to pursue economic development and protect the environment at the same time, humans must seek ways to minimize waste generation. Strategies that have served society well over the years include reusing and recycling materials that would otherwise become waste. Furthermore, a significant quantity of generated waste is dependent on the source of energy. For example, the mining of fossil fuels or hydrocarbons such as coal causes enormous water and land pollution. In addition, the combustion of hydrocarbons releases a considerable quantity of waste into the air. Investments in renewable energy sources such as solar and wind power contribute to waste minimization and to a cleaner and healthier environment.
Environmental risk assessment is:
(A) A method of generating new empirical data on health effects
(B) A method of performing basic research
(C) A synthesis of existing scientific information, often aimed at addressing specific regulatory or policy issues
(D) A method of determining the cause of a disease
Environmental risk assessment is:
(C) A synthesis of existing scientific information, often aimed at addressing specific regulatory or policy issues
Reference: Frumkin, p. 941
Hazard identification accomplishes the following:
(A) Describes the relationship between exposure and disease
(B) Identifies and selects the environmental agents for assessment
(C) Measures the magnitude, duration, and timing of human exposure
(D) Identifies the completed exposure pathway
Hazard identification accomplishes the following:
(B) Identifies and selects the environmental agents for assessment
Reference: Frumkin, p. 942
Exposure assessment attempts to answer all of the following questions except:
(A) Toxicity of the exposure
(B) Frequency and duration of exposure
(C) Population exposed
(D) Route of exposure
Exposure assessment attempts to answer all of the following questions except:
(A) Toxicity of the exposure
Reference: Frumkin, p. 942
A remote population of Pacific Islanders has lived without influence from the outside world for several centuries. The islanders were introduced to cigarettes as the influence of Western culture impacted their island about 25 years ago. The incidence of lung cancer is now high in the islanders who started to smoke 20 or more years ago. The observation of high levels of lung cancer after years of smoking is:
(A) Unusual for Pacific Islanders who smoke
(B) Typical for any population of smokers
(C) Inconsistent with the standard model of tumor initiation, promotion, and progression
(D) Insufficiently explained by the information above
A remote population of Pacific Islanders has lived without influence from the outside world for several centuries. The islanders were introduced to cigarettes as the influence of Western culture impacted their island about 25 years ago. The incidence of lung cancer is now high in the islanders who started to smoke 20 or more years ago. The observation of high levels of lung cancer after years of smoking is:
(B) Typical for any population of smokers
A long lag period between the start of smoking and tumor appearance is normal. The processes of initiation, promotion, and tumor progression occur over this time period in smokers (classic tobacco epidemiology).
Which of the following methods allows for the conduct of the most accurate exposure assessment in workers?
(A) Determination of the chemical in the air
(B) Biomonitoring determination of metabolites of the chemicals in blood and urine
(C) Determination of the chemical on the skin
(D) Estimation of the exposure by taking an occupational history
Which of the following methods allows for the conduct of the most accurate exposure assessment in workers?
(B) Biomonitoring determination of metabolites of the chemicals in blood and urine
Biomonitoring gives the best estimate for individual exposure. In addition, information about individual susceptibilities can be deduced. Air, skin, and interview do not yield information about uptake, metabolism, and individual susceptibilities.
Scenario for Questions 16-19.
Several years ago, a cottage industry existed at an elevation of 1,000 meters above sea level in a mountainous region of Japan . In the wintertime, inhabitants earned their living by manufacturing tatami mats. The indoor work was carried out in so-called kakoi (closed rooms), with tightly seal ed windows and wall crevices. The crowded rooms, heated by an open charcoal fire, provided approximately 5 cubic meters of air volume per person, about as much as a Boy Scout tent. In the beginning stage of disease, affected workers complained of stiffness in the shoulders, backache, fat igue, and dizziness. As the disease progressed, workers became short of breath on exertion and experienced tightness and pain below the breast bone, numbness in the arms and hands, and swelling of the face. The att acks of shortness of breath occurred mostly at night, whereas the episodes of pain and tightness around the heart, a condition known as angina pectoris, followed light work during the day.
The most likely contaminant/pollutant causing the described symptoms was:
(A) Sulfur dioxide
(B) Particulates
(C) Carbon monoxide
(D) Carbon dioxide
The most likely contaminant/pollutant causing the described symptoms was:
(C) Carbon monoxide
Carbon monoxide is a common indoor air pollutant produced by combustion appliances. The open charcoal fire and tightly sealed rooms suggest that buildup of carbon monoxide and other combustion byproducts in the space could pose a toxic hazard through formation of carboxyhemoglobin in the blood. This would limit the ability of blood to carry oxygen to the tissues, resulting in shortness of breath and possibly chest pains (angina pectoris) upon exertion. Coal combustion also produces particulate matter and carbon dioxide and can produce sulfur dioxide as well if high-sulfur coal is used, but the most likely cause of the described symptoms is carbon monoxide.
Reference: Nadakavukaren, pp. 393-397
Scenario for Questions 16-19.
Several years ago, a cottage industry existed at an elevation of 1,000 meters above sea level in a mountainous region of Japan . In the wintertime, inhabitants earned their living by manufacturing tatami mats. The indoor work was carried out in so-called kakoi (closed rooms), with tightly seal ed windows and wall crevices. The crowded rooms, heated by an open charcoal fire, provided approximately 5 cubic meters of air volume per person, about as much as a Boy Scout tent. In the beginning stage of disease, affected workers complained of stiffness in the shoulders, backache, fat igue, and dizziness. As the disease progressed, workers became short of breath on exertion and experienced tightness and pain below the breast bone, numbness in the arms and hands, and swelling of the face. The att acks of shortness of breath occurred mostly at night, whereas the episodes of pain and tightness around the heart, a condition known as angina pectoris, followed light work during the day.
The major human portal of entry for the contaminant/pollutant was:
(A) Dermal
(B) Oral
(C) Respiratory
(D) Transplacental
The major human portal of entry for the contaminant/pollutant was:
(C) Respiratory
The scenario does not suggest the presence of a specific skin absorption or ingestion hazard, nor are the symptoms related to effects on a developing fetus. Inhalation of airborne combustion byproducts, specifically carbon monoxide, is indicated.
Reference: Nadakavukaren, pp. 393-397
Scenario for Questions 16-19.
Several years ago, a cottage industry existed at an elevation of 1,000 meters above sea level in a mountainous region of Japan . In the wintertime, inhabitants earned their living by manufacturing tatami mats. The indoor work was carried out in so-called kakoi (closed rooms), with tightly seal ed windows and wall crevices. The crowded rooms, heated by an open charcoal fire, provided approximately 5 cubic meters of air volume per person, about as much as a Boy Scout tent. In the beginning stage of disease, affected workers complained of stiffness in the shoulders, backache, fat igue, and dizziness. As the disease progressed, workers became short of breath on exertion and experienced tightness and pain below the breast bone, numbness in the arms and hands, and swelling of the face. The att acks of shortness of breath occurred mostly at night, whereas the episodes of pain and tightness around the heart, a condition known as angina pectoris, followed light work during the day.
The carboxyhemoglobin levels in the exposed workers:
(A) Was found in the kidneys
(B) Was elevated
(C) Stayed the same
(D) Dropped below 10% of normal levels
The carboxyhemoglobin levels in the exposed workers:
(B) Was elevated
Carbon monoxide reacts with hemoglobin in the red blood cells to produce carboxyhemoglobin, thereby tying up the hemoglobin and reducing the ability of the blood cells to carry oxygen. Carboxyhemoglobin concentration increases over the duration of exposure to carbon monoxide gas, approaching a maximum concentration that is determined by the airborne gas concentration. Therefore in this scenario an elevated carboxyhemoglobin level would be expected.
Reference: Nadakavukaren, pp. 393-397
Scenario for Questions 16-19.
Several years ago, a cottage industry existed at an elevation of 1,000 meters above sea level in a mountainous region of Japan . In the wintertime, inhabitants earned their living by manufacturing tatami mats. The indoor work was carried out in so-called kakoi (closed rooms), with tightly seal ed windows and wall crevices. The crowded rooms, heated by an open charcoal fire, provided approximately 5 cubic meters of air volume per person, about as much as a Boy Scout tent. In the beginning stage of disease, affected workers complained of stiffness in the shoulders, backache, fat igue, and dizziness. As the disease progressed, workers became short of breath on exertion and experienced tightness and pain below the breast bone, numbness in the arms and hands, and swelling of the face. The att acks of shortness of breath occurred mostly at night, whereas the episodes of pain and tightness around the heart, a condition known as angina pectoris, followed light work during the day.
Which term is used to characterize the social condition of unequal distribution of environmental hazards experienced by minority populations or groups with low income?
(A) Environmental equity
(B) Environmental justice
(C) Environmental pollution
(D) Environmental democracy
Which term is used to characterize the social condition of unequal distribution of environmental hazards experienced by minority populations or groups with low income?
(B) Environmental justice
Churches and other nonprofit interest groups that started the environmental fairness movement in the 1980s articulated their mission using the term "Environmental Justice". The inverse is environmental injustice. The overarching premise is fairness in the distribution of the burden of pollution across all population groups regardless of race, ethnicity or socio-economic status. The term "Environmental equity" is not the best answer because while it may be a component of environmental justice, it is not all that environmental justice is. Environmental justice is a much broader term, encompassing equity, equality and fairness. The term "Environmental pollution" is vaguely expressive of the message and is therefore not a good answer. The term "Environmental democracy" is completely wrong because it is not about majority rule. If it were a matter of majority rule, then minority health can be in serious jeopardy.
Reference: Johnson, p. 370
Executive Order 12898, entitled "Federal Actions to Address Environmental Justice in Minority Populations and Low Income Populations," is an example of which policy-making model?
(A) Policy Action Change and Monitoring (PACM) model
(B) Exposure-response relationship model
(C) Integrated assessment model
(D) NIMBY model
Executive Order 12898, entitled "Federal Actions to Address Environmental Justice in Minority Populations and Low Income Populations," is an example of which policy-making model?
(A) Policy Action Change and Monitoring (PACM) model
Where there is a legislative void or inaction on a matter that is of a pressing concern (emergency or non-emergency) an executive order (at the federal or state government level) may be used by the president or the governor to require and direct action to achieve a desired outcome. In this case, pressure from communities led to an action (executive order) that brought about change. To sustain this change, communities and the government in this case would monitor the policy outcome the president or governor intended. Communities could also use this model to bring about an environmental change, for example a change in the zoning code, or prevent what they perceive as a detrimental effect on the environment, for example locating an industrial facility in their neighborhood. Options B and C are not necessarily a policy intervention but rather scientific initiatives that could inform policy. Option D is a slogan of some people who do not welcome pollution sources in their neighborhood. This slogan can be driven more by public perceptions that may not be grounded in science. While it could politically pressure a president to make an executive order, such an executive order still would more appropriately fit into the PACM model.
Reference: Johnson, p. 401
All of the following are responsibilities prescribed for Federal agencies under Executive Order 12898, except:
(A) Creation of an interagency working group
(B) Development of agency strategies
(C) Federal agency responsibilities for Federal programs
(D) Mandate for the polluters-pay principle
All of the following are responsibilities prescribed for Federal agencies under Executive Order 12898, except:
(D) Mandate for the polluters-pay principle
Options A, B and C are all contained in the Executive Order 12898 as necessary items of action for the EPA to implement in order to fulfill the purpose of the Order. Option D is in the domain of existing environmental laws such as the CERCLA/SUPERFUND, the Federal Oil Pollution Act, and also through the permit and penalty regimes of the CAA and CWA. Therefore, an executive order is not needed to effectuate option D
Reference: Johnson, p. 401
Scenario for Questions 22-24.
The burden of environmental contamination and pollution is not equally distributed. Some areas and populations, particularly people of color and low-income communities, have been disproportionately affected by environmental insults or lack equal access to social, economic, and environmental amenities. Understanding why this happens is crucial, and new methods of collaboration must be developed to redress the harm, restore human and environmental health, allow sustainable development to proceed, and develop policies to prevent these inequities from recurring.
Along the Texas-Mexico border, there are many examples of environmental insults that disproportionately affect the Hispanic segment of the population. Many of these people live in colonias (neighborhoods). Some of these colonias are very primitive, with unpaved roads, no running water (water is brought in via tanker trucks), and no public sewage. The lack of a potable water supply is an example of environmental insult.
There are several methods for making drinking water available. Which of the following is not an acceptable method from a health standpoint?
(A) Using a tank truck to deliver water from a potable source
(B) Using a community tap connected to a potable source
(C) Pumping water from an uncontaminated aquifer
(D) Pumping water directly from a river
There are several methods for making drinking water available. Which of the following is not an acceptable method from a health standpoint?
(D) Pumping water directly from a river
Reference: Friis, pp. 202-209
Scenario for Questions 22-24.
The burden of environmental contamination and pollution is not equally distributed. Some areas and populations, particularly people of color and low-income communities, have been disproportionately affected by environmental insults or lack equal access to social, economic, and environmental amenities. Understanding why this happens is crucial, and new methods of collaboration must be developed to redress the harm, restore human and environmental health, allow sustainable development to proceed, and develop policies to prevent these inequities from recurring.
Along the Texas-Mexico border, there are many examples of environmental insults that disproportionately affect the Hispanic segment of the population. Many of these people live in colonias (neighborhoods). Some of these colonias are very primitive, with unpaved roads, no running water (water is brought in via tanker trucks), and no public sewage. The lack of a potable water supply is an example of environmental insult.
All of the following are potential sources of contamination of a water supply that is delivered by a tanker truck to a storage tank located at the home, except for:
(A) Storage tank at the home
(B) Plumbing from tank into the home
(C) Source of potable water
(D) Source of river water
All of the following are potential sources of contamination of a water supply that is delivered by a tanker truck to a storage tank located at the home, except for:
(C) Source of potable water
Reference: Yassi et al., pp. 227-228
Scenario for Questions 22-24.
The burden of environmental contamination and pollution is not equally distributed. Some areas and populations, particularly people of color and low-income communities, have been disproportionately affected by environmental insults or lack equal access to social, economic, and environmental amenities. Understanding why this happens is crucial, and new methods of collaboration must be developed to redress the harm, restore human and environmental health, allow sustainable development to proceed, and develop policies to prevent these inequities from recurring.
Along the Texas-Mexico border, there are many examples of environmental insults that disproportionately affect the Hispanic segment of the population. Many of these people live in colonias (neighborhoods). Some of these colonias are very primitive, with unpaved roads, no running water (water is brought in via tanker trucks), and no public sewage. The lack of a potable water supply is an example of environmental insult.
Safe, high-quality drinking water is an essential aspect of public health. Potable water should not contain:
(A) Disinfection residual
(B) Chlorine
(C) Biocides
(D) Fluorides
Safe, high-quality drinking water is an essential aspect of public health. Potable water should not contain:
(C) Biocides
References: Frumkin, pp. 499-500 | Yassi et al., pp. 220-221
Which of the following disinfection methods is most commonly used in US drinking water supply systems?
(A) Ozonation
(B) Bromination
(C) Chlorination
(D) Ultraviolet irradiation
Which of the following disinfection methods is most commonly used in US drinking water supply systems?
(C) Chlorination
Although disinfection can be accomplished with ozone, bromine, and ultraviolet radiation, most municipalities use chlorine. Chlorine is easy and relatively cheap to use, does not cause the taste problems associated with bromine, and a residual chlorine concentration in the water provides protection against re-contamination in the water distribution system.
Reference: Nadakavukaren, pp. 502-505
Which of the following water-borne disease organisms is very difficult to kill by chemical disinfection of drinking water supply systems and has caused a major US disease outbreak in recent years?
(A) Vibrio cholerae (causes cholera)
(B) Cryptosporidium (causes Cryptosporidiosis)
(C) Giardia lamblia (causes Giardiasis)
(D) E. coli (causes acute gastroenteritis)
Which of the following water-borne disease organisms is very difficult to kill by chemical disinfection of drinking water supply systems and has caused a major US disease outbreak in recent years?
(B) Cryptosporidium (causes Cryptosporidiosis)
Protozoa of the genus Cryptosporidium are highly resistant to chlorine disinfection, and are responsible for numerous and increasing waterborne disease outbreaks. The largest waterborne disease outbreak in US history, which occurred in Milwaulkee, Wisconsin in 1993, was caused by contamination of the city's drinking water with this organism; over 400,000 residents became ill. Contact with contaminated recreational waters, such as in swimming pools, is a particularly common source of exposure. Giardia is another chlorine-resistant parasite, but has not been associated with large-scale outbreaks.
References: Nadakavukaren pp. 522
http://www.cdc.gov/nceh/ehs/Topics/Cryptosporidium.htm
Municipal sewage is typically processed to remove organic material before disposing of the treated water. In large cities this treatment will generally consist of:
(A) Biological treatment in an aerated activated sludge system, followed by settling to remove sludge solids, then chlorination prior to discharge.
(B) Chemical treatment by coagulation and flocculation, followed by settling to remove solids, then chlorination prior to discharge.
(C) Filtering through sand beds to remove organic solids, followed by chlorination prior to discharge.
(D) Super-chlorination to destroy organic materials, followed by discharge.
Municipal sewage is typically processed to remove organic material before disposing of the treated water. In large cities this treatment will generally consist of:
(A) Biological treatment in an aerated activated sludge system, followed by settling to remove sludge solids, then chlorination prior to discharge.
The aerated activated sludge socondary treatment process is effective in removing organic materials from municipal sewage. The organics are consumed by a mix of aerobic biological organisms termed "activated sludge". Sludge is removed from the treated water by gravitational settling, and the water is disinfected by chlorination before discharge (e.g. to a receiving river) The chemical coagulation / flocculation / settling process is used to treat water distined for the drinking water supply system, and is usually required when the water is taken from a surface water source such as a lake or river. Filtering through sand beds is also used to treat drinking water, not municipal sewage. Super-chlorination is not an effective treatment for municipal sewage.
Reference: Nadakavukaren pp. 496-505
The nutrient-rich solids produced as a byproduct of municipal sewage treatment and often proposed for use a soil amender in agriculture is termed:
(A) Hazardous waste
(B) Suspended Solids
(C) Biochemical Oxygen Demand (BOD)
(D) Sludge
The nutrient-rich solids produced as a byproduct of municipal sewage treatment and often proposed for use a soil amender in agriculture is termed:
(D) Sludge
The secondary biological treatment process used by most large municipalities produces substantial quantities of settled solids, termed "sludge", composed largely of masses of bacteria. About half of this organic-rich material is recycled each year as fertilizer, but its use is strictly regulated by the EPA because some sludges may contain potentially harmful concentrations of heavy metals and other toxic substances.
Reference: Nadakavukaren pp. 505-508
The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA):
(A) Established the "Superfund" for financing cleanup of hazardous waste disposal sites, and the National Priorities List identifying such sites
(B) Created the United States Environmental Protection Agency (EPA) and authorized the agency to regulate environmental pollutants
(C) Established requirements and procedures for the proper disposal of municipal solid waste, e.g. via properly designed and operated municipal landfills
(D) Imposed the requirement for federal agencies to prepare Environmental Assessments and Environmental Impact Statements of the environmental effects of proposed federal agency actions
Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA):
(A) Established the "Superfund" for financing cleanup of hazardous waste disposal sites, and the National Priorities List identifying such sites
CERCLA, initially enacted in 1980 and later reauthorized and expanded in the Superfund Amendments and Reauthorization Act (SARA) of 1986, provides funding and authorizes the EPA to regulate and remediate hazardous waste storage and disposal sites. There are currently over 1200 sites listed in the NPL.
Resource: Nadakavukaren pp. 581-586
Which of the following is not a disease that can be contracted by the food-borne route?
(A) Salmonellosis
(B) Giardiasis
(C) West Nile Virus Neuroinvasive Disease
(D) Hepatitis A
Which of the following is not a disease that can be contracted by the food-borne route?
(C) West Nile Virus Neuroinvasive Disease
West Nile Virus Neuroinvasive Disease is caused by the transmission of West Nile Virus to humans through the bite of an infected mosquito. WNVND is seasonal with the highest rates in the warmer months when mosquito populations are highest. Only about 1 in 150 infected persons will become seriously ill, but about 1 in 5 may have milder symptoms.
References: Nadakavukaren pp. 238-240 | http://www.cdc.gov
A primary technique for preventing food-borne disease in cafeteria-type food service establishments is:
(A) Encouraging customers to wash their hands before eating
(B) Maintaining warm foods at a sufficiently high holding temperature
(C) Weekly application of pesticides to control cockroaches
(D) Annual physical examinations of food service workers
A primary technique for preventing food-borne disease in cafeteria-type food service establishments is:
(B) Maintaining warm foods at a sufficiently high holding temperature
Microbial food contaminants such as Salmonella, Campylobacter, and E. coli may multiply rapidly at warm temperatures (between about 41-140F or 5-60C). Maintaining warm foods above 140F (60C) will kill actively growing bacteria.
Reference: Nadakavukaren pp. 304-307
Which of the following is the most commonly occurring mosquito-borne disease in the United States?
(A) West Nile Virus Neuroinvasive Disease
(B) Malaria
(C) Dengue Fever
(D) Yellow Fever
Which of the following is the most commonly occurring mosquito-borne disease in the United States?
(A) West Nile Virus Neuroinvasive Disease
WNVND is common throughout the US, particularly in the warm months when mosquito populations are highest and people spend more time outdoors. Malaria, Dengue Fever, and Yellow Fever rarely occur in the US.
References: Nadakavukaren pp. 238-240 | http://www.cdc.gov
Rocky Mountain Spotted Fever and Lyme Disease are examples of diseases transmitted by:
(A) Mosquitoes
(B) Polluted water
(C) Contaminated food
(D) Ticks
Rocky Mountain Spotted Fever and Lyme Disease are examples of diseases transmitted by:
(D) Ticks
Ticks are responsible for transmission of a variety of diseases, of which Rocky Mountain Spotted Fever and Lyme Disease are most common. Other tick-borne diseases in the US include erlichiosis, Q-fever, relapsing fever, tularemia, and tick paralysis.
References: Nadakavukaren pp. 243-245 | http://www.cdc.gov/niosh/topics/tick-borne
Lead contamination of outdoor air in large cities has been greatly reduced over the past 25 years through:
(A) Restrictions on the sale of lead-based paints
(B) A ban on the sale of gasoline containing lead anti-knock compounds
(C) Widespread use of clean-burning coal in electric power plants
(D) Strict regulations on the proper disposal of batteries containing lead
Lead contamination of outdoor air in large cities has been greatly reduced over the past 25 years through:
(B) A ban on the sale of gasoline containing lead anti-knock compounds
Gasoline with lead anti-knock additives was phased out of use in the US during the 1980s. This action is believe to be the primary factor in the more than 80% reduction in the average blood lead levels of Americans compared to the 1970s.
Resource: Nadakavukaren pp. 218-220
Epidemiologic studies have shown a positive association between the concentration of particulate matter (PM) in ambient air and:
(A) An increased incidence of respiratory-related morbidity and mortality
(B) The destruction of the stratospheric ozone layer
(C) Effects on global climate change, specifically increased Global Warming
(D) Declines in bird populations due to thinning of their egg shells
Epidemiologic studies have shown a positive association between the concentration of particulate matter (PM) in ambient air and:
(A) An increased incidence of respiratory-related morbidity and mortality
Numerous studies have shown a positive correlation between the incidence of respiratory-related morbidity and mortality and the concentration of air pollutants, particularly airborne particulate matter (PM) small enough to penetrate to the respiratory tissues of the deep lung. The specific mechanism(s) and/or PM constituent(s) responsible for this observed increase remain unclear.
References: Nadakavukaren pp. 393-394 | http://www.epa.gov/air/particlepollution
In part due to the public attention focused on environmental pollution by Rachel Carson's book "Silent Spring", as well as studies such as those showing a drastic decline in the American Bald Eagle population, a ban was issued on the use of:
(A) Chlorofluorocarbon (CFC) refrigerant gases
(B) Leaded gasoline
(C) DDT pesticide
(D) Asbestos insulation materials
In part due to the public attention focused on environmental pollution by Rachel Carson's book "Silent Spring", as well as studies such as those showing a drastic decline in the American Bald Eagle population, a ban was issued on the use of:
(C) DDT pesticide
DDT is essentially non-toxic to humans and was widely used in past years as a general purpose pesticide. However, it was shown to "bioaccumulate" through the food chain of birds and to cause thinning of the birds' egg shells, resulting in broken eggs and a severe decline in some species including Bald Eagles, falcons, and pelicans.
References: Nadakavukaren pp. 252-254
http://www.epa.gov/pesticides/factsheets/chemicals/ddt-brief-history-status.htm
River water pollution due to storm water runoff from chemically fertilized farm fields is an example of:
(A) Area source pollution
(B) Point source pollution
(C) Accidental and unforeseeable pollution
(D) Unpreventable and inconsequential pollution
River water pollution due to storm water runoff from chemically fertilized farm fields is an example of:
(A) Area source pollution
An area water pollution source (also called a "non-point source") such as a fertilized or freshly plowed farm field, an animal feed lot, or an agricultural waste storage area (e.g. for manure from poultry feeding operation) requires a different control approach compared to point sources such as factory smokestacks or waste discharge pipes. Area sources are sometimes quite difficult to manage due to their size.
Reference: http://www.epa.gov/owow/nps/
Nitrates in ground water are of particular concern in rural communities that rely on well water because:
(A) Nitrates can cause Blue-Baby Syndrome in infants
(B) Nitrates are potent carcinogens in adults
(C) The well water will be undrinkable due to taste, odor, and color problems
(D) The well water will form nitric acid and become corrosive to metal pipes in the water system
Nitrates in ground water are of particular concern in rural communities that rely on well water because:
(A) Nitrates can cause Blue-Baby Syndrome in infants
Ingestion of nitrate-polluted water by infants under 6 months of age can cause the formation of potentially fatal levels of methemoglobin in the red blood cells. Methemoglobin restricts the ability of the cells to carry oxygen to the tissues, and although adults are generally unaffected, "methemoglobinemia" can be fatal to the infants. Methemoglobinemia produces a characteristic blue tint in the tissues due to oxygen deficiency (cyanosis), hence the name "Blue-Baby Syndrome."
Reference: Nadakavukaren pp. 529-530
The Stratospheric Ozone Layer is a concern because:
(A) Degradation of the Ozone Layer increases the amount of ultraviolet radiation reaching the Earth's surface
(B) An increase in the density of the Ozone Layer causes increases in Smog air pollution
(C) The Ozone Layer is a primary contributor to Global Warming
(D) An increase in the density of the Ozone Layer causes Acid Rain that can damage forests and lakes
The Stratospheric Ozone Layer is a concern because:
(A) Degradation of the Ozone Layer increases the amount of ultraviolet radiation reaching the Earth's surface
Ozone in the outer atmosphere blocks a substantial portion of the ultraviolet radiation impinging on the earth. Without this protective layer more UV would penetrate to the earth's surface, and modelers predict that this could cause a range of adverse effects from increased rates of human skin cancers to catastrophic damage to ocean plankton and plankton-dependent fish populations.
Reference: Nadakavukaren, pp. 363-369
The "Greenhouse Gas" of primary concern in global warming is:
(A) Chlorofluorocarbon refrigerant
(B) Carbon monoxide
(C) Sulfur dioxide
(D) Carbon dioxide
The "Greenhouse Gas" of primary concern in global warming is:
(D) Carbon dioxide
Carbon dioxide in the atmosphere absorbs and re-emits infrared radiation emitted from the earth's surface, acting as an insulating blanket that helps moderate the earth's temperature. This is termed the Greenhouse Effect. Atmospheric carbon dioxide concentration has increased substantially in recent decades due to fossil fuel combustion, causing great concern about the potential adverse effects of excessive global warming.
Reference: Nadakavukaren, pp. 369-389