explosures radiation doses and their effects Chap 6, sherer 33-34 bushong
1000 Gy or 100,000 rads
how much radiation causes instant death?
what is the result of exposure of 1,000 Gy?
gross disruption of cell form and structure, chemical changes, DNA breaks up, proteins coagulate
what is the result of exposure of 1-10 grays?
cell looses its ability to duplicate and produce daughter cells
radiosenstivity of invidual types of cells governs the dose required to cause ___________
cells die without attempting cell division, formerly called interphase death, or programed cell death
relatively small doses can cause ______, less than whats required to produce apoptosis in slowly dividing or nondividing cells
radiation inhibits cell division, and cell dies in 1 or more divisions
.01 GY or 1 rad causes ______ _______
failure of cell to start dividing on time, may resume normal fuction after its 'late start'
interference of function
permanant or temporary impairment of function other than division, may occur as a result of exposure to ionizing radiation, repair enzymes may fix, and cell can recover and continue function
caused by whole body does of 0.25 GY or 25 rad within a few days
0.25 GY or 25r ad within a few days
what amount of radiation can cause hemologic depression?
3-4 GY or 300-400 rads
amount of radiation that causes death, without treatment
whole body dose over 5 GY
what amount of radiation causes death within 30-60 days?
radiation amount causing severe depletion of bone marrow, taking longer than a few weeks to repopulate
less than 1 GY or 100 rad
exposure amount allowing repopulation of bone marrow cells in a few weeks
greater than 10 GY
radiation amount which can cause a permanent decrease in stem cells which create blood
a few hundred centigrays
radiation amount to cause death of lymphocyte cells
.25 or 25 rads
amount that can depress the amount of lymphoctyes in blood, which can impair immune system
amount which reduces number of neutrophils in blood
upon exposure of radiation, the initial response causes an INCREASE in these cells, then with increased exposure they rapidly decrease in number, and then more slowly. Takes about 2 months to fully repopulate
less tha 0.5 GY or 50 rads
radiation that lowers thromboytes in blood
exposure amount which requires 2 months for thromboytes to recover to original amount
over 50 GY or 5000 rads
very high exposure which causes death in a matter of hours
the window of maximum radiosensitivity to fetus
0.1 SV (10 rem)
radiation amount causing as much as 4% risk of mental retardation
less than 0.05 SV or 5 rem
radiation amount in a routine flouro abdomen
2 Gy or 200 rad
may cause temporary male sterility for up to 12 months
5-6 GY or 500-600 rad
amount which may cause permanent male sterility
0.1 GY- 10 rads
radiation amount which can cause genetic defects on future generations to male reproductive cells