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Management of Commercially Generated Radioactive Waste - U.S. ...

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E.8<br />

fail to demonstrate any important effect <strong>of</strong> irradiation on the irregularly<br />

inherited diseases, or on general health and well being," and concludes that "the<br />

collectively numerous irregularly inherited diseases <strong>of</strong> man are unlikely to be<br />

substantially increased in frequency by exposure <strong>of</strong> his germ plasm to radiation"<br />

(Newcombe 1975).<br />

3. Disorders due to chromosomal aberrations include diseases characterized by changes<br />

in the number <strong>of</strong> chromosomes, or in the structural sequence within chromosomes.<br />

It is generally agreed that these diseases will show little increase as a result<br />

<strong>of</strong> low-level, low-LET irradiation, and they were not quantified in the BEIR<br />

Report. The 1977 UNSCEAR Report includes a numerical estimate for such effects.<br />

4. Spontaneous abortions are known to occur as a result <strong>of</strong> chromosomal effects, <strong>of</strong>ten<br />

so early in pregnancy as to be undetectable. Such effects have been generally<br />

excluded as not a relevant health effect (NAS-NRC 1972).<br />

In addition to the above specifically identifiable genetic effects, there may well be<br />

genetic influence on other unquantifiable aspects <strong>of</strong> physical and mental ill health. The<br />

BEIR Report assumed that two-tenths <strong>of</strong> this "ill health".was due to genetic factors related<br />

to mutation, acknowledging that "it may well be less, but few would argue that it is much<br />

higher" (p. 57). Using this factor and a mutation doubling dose <strong>of</strong> 100 rem, one calculates<br />

an eventual 0.2% increase in "ill-health" as a consequence <strong>of</strong> continual exposure to 1 rem<br />

per generation. Such ill-defined effects cannot be quantitatively compared to specific<br />

genetic effects, or carcinogenic effects, not can they be stated on a man-rem basis.<br />

Table E.2.1 summarizes the BEIR Report and UNSCEAR Report genetic risk estimates.<br />

The EPA has employed an estimate <strong>of</strong> 300 genetic effects per million man-rem (EPA 1973,<br />

Part III), as has also the Medical Research Council in England (MRC 1975). The newer data<br />

on the normal frequency <strong>of</strong> autosomal dominant disorders (Trimble and Doughty 1974), and<br />

Newcombe's (1975) evaluation <strong>of</strong> the significance <strong>of</strong> multifactoria disorders, lead to an<br />

estimate for total genetic effects <strong>of</strong> only 10 per million man-rem. All <strong>of</strong> these estimates<br />

are for total effects, to be experienced over all future generations.<br />

TABLE E.2.1. Estimates <strong>of</strong> Genetic Effects <strong>of</strong> Radiation Over All Generations<br />

BEIR UNSCEAR EPA Newcombe<br />

Type <strong>of</strong> Effect Report (1972) Report (1977) (1973) (1975)<br />

Autosomal Dominant<br />

Disorders 50-500 100 10<br />

Chromosomal Disorders<br />

40<br />

Multifactorial Disorders 10-1000 45<br />

Total 60-1500 185 300 10

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