The main function of the kidneys is to filter the blood and eliminate wastes. Because the waste gets concentrated in the process, toxins can be at much higher levels in the kidneys. Toxins that damage this organ are known as nephrotoxins.
Most heavy metals fall into this category, including mercury, arsenic, and lithium. Many halogenated (i.e., chlorinated) organic compounds are also nephrotoxins such as tetrachloroethylene, carbon tetrachloride, and chloroform. Other chemicals that damage the kidneys include carbon disulfide, methanol, toluene, and ethylene glycol.
Substances capable of producing blood disorders are called hematoxins. Chemicals that affect the bone marrow, which is the source of most of the components of blood, are arsenic, bromine, methyl chloride, and benzene. Chemicals that affect platelets, which are cell fragments that help in the process of blood clotting, are aspirin, benzene, and tetrachloroethane.
Chemicals that affect white blood cells, which help the body defend against infection, are naphthalene and tetrachloroethane. Arsine, naphthalene, and warfarin can affect red blood cells, which carry oxygen throughout the body. Effects in the exposed individual may include reduced red blood count, or anemia; reduced white blood cell count, which leaves the victim susceptible to disease; and reduced platelet count, which increases the possibility of hemorrhaging.
Reproductive toxins can cause sterility, infertility, or spontaneous abortions. They can also affect an individual's hormone levels and activity. Examples of male reproductive toxins are mercury, lead, DDT, PCBs, dioxin, benzene, toluene, and xylene. Examples of female reproductive toxins are DDT, PCBs, parathion, and diethylstilbestrol. In the ACGIH publication: Threshold Limit Values for Chemical Substances and Physical Agents, OSHA Standard 29 CFR Part 1910.1000, and other Standard references. These documents identify substances that can be readily absorbed through the skin, mucous membranes, and/or eyes by either airborne exposure or direct contact with a liquid.
This information, like most available information on skin absorption, is qualitative. It indicates whether, but not to what extent, a substance can pose a dermal hazard. Thus, decisions made concerning skin hazards are necessarily judgmental.
Quantitative data on eye irritation is not always available. Where a review of the literature indicates that a substance causes eye irritation, but no threshold is specified, one should have a competent health professional evaluate the data to determine the level of personal protection needed for workers.