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

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Most of the argument on the RSS report centered on low dose rate,
low LET radiation. Alpha radiation dose response curves are usually The genetic effects estimates attributed to the BEIR report and
characterized as both linear and dose rate independent (BEIR, 1972; EPA in Table E.3 are not comparable to those given in the 1977 UNSCEAR
UNSCEAR, 1977) or as possibly providing underestimated effects at low report since they assume a 30-year reproductive generation time. To
doses (Martin Brown, J., "Linearity vs. Non Linearity of Dose Response compare the BEIR and EPA estimates with those of UNSCEAR, the BEIR and
for Radiation Carcinogenesis," Health Physics, 31, pp.231- 2 4 5, 1976; EPA estimates should be multiplied by a factor of about 0.6 to adjust
Archer, V.E., Radford, E.P., and Axelson, 0.; "Radon Daughter Cancer in for a 30-year population generation vs. the current, approximately
Man: Factors in Exposure-Response Relationships," Health Physics 50-year population generation. More recent EPA estimates have been
Society Annual Meeting, June 1978). No reports except the RSS report adjusted for the current population generation (EPA 520/1-76-010), to
consider a threshold curve a viable concept, yield 200 genetic effects, close to the UNSCEAR 1977 estimate.
129. (Page E.4, Table E.1) A column in Table E.1, headed 131. (Page E.9, Table E.4) The column titled "Mays(19)" may contain an
"Environmental Protection Agency," purports to be the risk estimates error. Mays, et al. (reference 19) estimated 200 bone cancer
used by EPA. They are actually averages for various risk models used
by EPA in reports and therefore are not directly comparable to the
deaths/10 person-rads. Using a 0 of 10, this would be equivalent to
20 bone cancer deaths/10 6 other risk estimates in the table.
person-rem. In a contemporary paper (Mays,
C.W., Estimated Risk from 39 Pu to Human Bone, Liver and Lung,
The estimates
of 54 leukemia death person-rem listed in the
The estimates of 54 leukemia deaths/000 person-rem lis ted in the
pp. 373-384 in Biological and Environmental Effects of Low-Level
Radiation Vol. II, IAEA, Vienna, 1976), Mays estimated (again assuming
table were extracted from EPA 520/9-73-003-B (reference 4). As stated a Q of 10) 20 lung cancer deaths, 20 bone cancer deaths and 10 liver
in that report (p. A-14), the risk conversion factors are average
values for absolute and relative risks in the BEIR Report, 1972.
cancer deaths per 106 person-rem.
Moreover, they apply only to the dosimetric models used in EPA report EPA in its guidance on transuranium elements (EPA 520/4-77-016)
520/9-73-003-B. provided an analysis of the health impact of exposure to transuranium
elements in the environment which includes both risk and dose-rate
The EPA risk for thyroid listed in Table E.I, 15 thyroid cancer estimates for a cohort of 100,000 exposed since birth. This guidance
deaths/10 6 person-rem, is referenced to EPA 520/4-76-017 is supplemented by technical reports, Technical Report EPA 520/4-78-010
(reference 6). That risk estimate cannot be found the cited reference. and Technical Note CSD-78-1, which provide background information for
However, on p. 96, ibid., it states "...., a population age weighted the basic guidance document. Since the health impact calculated in
value of 60 thyroid cancers per million rems to the thyroid was used." these reports is based on lifetime exposure and risk coefficients for
A similar risk estimate is shown in Tables 45 and 46 of EPA report specific organs, the results are not directly comparable with Table E.4
520/9-73-003-C, Environmental Analysis of the Uranium Fuel Cycle. but they are a more realistic estimate of health impact from
Part II - Nuclear Power Reactors, 1973. Note that these thyroid risk transuranium elements in the environment.
estimates refer to cases, not fatalities,-and so do not fit into
Table E.I. 132. (Page E.10, paragraph 6) Although BEIR, 1972 did not provide a
risk estimate for skin cancer, the 1978 Stockholm meeting of ICRP
130. (Page E.7, last paragraph and page E.8, Table E.3) Newcombe's suggested if a skin cancer risk is required, an estimate of 1 fatal
estimate of ten genetic effects based on a normal incidence rate of cancer per 106 person rem could be used. Averaging the risk
0.1 percent for autosomal dominant disorders has not been supported by estimates in UNSCEAR, 197 , the skin cancer incidence is around
other studies. Current incidence estimates are about 1 percent 0.5 cases per year per 10 person-rem; with a 6 percent mortality
autosomal dominant and X-linked disorders, the estimate in UNSCEAR, this would be about 2 fatal skin cancers per 106 person-rem. The
1977. 1977 UNSCEAR Report suggests alpha risk might be higher.
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133.(Appendix F) The description of the geology at the bottom of
page F.2 would be improved if there were some indication of the depth
of the basement rocks and of the general nature of the overlying rocks.