23.04.2013 Views

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

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

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

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

E.11<br />

TABLE E.4.1. Comparison <strong>of</strong> Transuranic Health Risk Estimates<br />

(Tumor deaths per million organ-rem)<br />

Mays Risk Estimates<br />

BEIR (1972) et al. Based on Data<br />

Hight 1<br />

Low MRC (1975) (1976) from Animals<br />

Lung tumors 100 16 25 60-200<br />

Bone tumors 17 2 5 4 10-100<br />

Liver tumors<br />

(a) Relative risk model with lifetime plateau (Newcombe 1975).<br />

(b) Absolute risk model with 30-year plateau (Necombe 1975).<br />

(c) Data from Bair and Thomas (1976).<br />

(d) Data from Bair (1974) and Mays et al. (1976).<br />

E.4.4 Data on Effects <strong>of</strong> Other Types <strong>of</strong> Radiation on Man<br />

Inferences concerning the effects <strong>of</strong> transuranic elements in man may be drawn from<br />

information available on the effects <strong>of</strong> other forms <strong>of</strong> ionizing radiation in man; e.g., data<br />

derived from medical, occupational, accidental, or wartime exposure <strong>of</strong> humans to different<br />

radiation sources, including external x-radition, atomic bomb gamma and neutron radiation,<br />

radium, radon and short-lived radon decay products. Such information has been summarized in<br />

the BEIR and UNSCEAR Reports, as previously described. England's Medical Research Council<br />

(1975), considering much the same information covered in the BEIR and UNSCEAR Reports,<br />

derived risk estimates specifically applicable to plutonium.<br />

Also <strong>of</strong> interest are recently accumulated data on the carcinogenicity <strong>of</strong> 2 2 4 Ra in<br />

human bone (Spiess and Mays 1971, 1972). These data are particularly relevant to risks from<br />

plutonium, since 22 4 Ra is predominantly an alpha emitter and, because <strong>of</strong> its very short<br />

half-life (3.64 days), irradiates only the surface layer <strong>of</strong> bone, in much the same manner<br />

as plutonium does. From these 22 4 Ra data, Mays et al. (1976) have estimated a bone cancer<br />

risk <strong>of</strong> 4 per million bone-rem.<br />

Table E.4.1 compares tumor risk estimates from these several sources. Quantitative<br />

application <strong>of</strong> these data to the very low exposure levels involved in population exposure<br />

resulting from commercial waste management practices is uncertain; however, the kinds <strong>of</strong> data<br />

presented in Table E.4.1 are reassuring because <strong>of</strong> their general agreement, and because they<br />

predict no unusual incidence <strong>of</strong> effects not contemplated in the selection <strong>of</strong> the general risk<br />

estimates used in this Statement.<br />

20<br />

( c )<br />

(d )

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!