Risk from Radiation ; At Rongelap there are two distinet populatiens at risk. One group . Ceslied the exposed greup) vas exposed acutely in 1954 and in addition was exposed to low levels of radiation in «@ protracted fashion from 1957 to present. Another Rroup (called the unexposed group) was exposed only from 1957 to present. The cancer mortality risk from & eingle exposure te radiation is protracted in time (see Figure 3), thus, the exposed group is experiencing risk from the 1954 expesure in addition to experiencing risk from the protracted exposure. TI have tabulated the retrespeetive and prespective annual risk for the Rengelap people in Table 4. I based the estimate on the rectanele approximation of annual risk given in Figure 3. L. Gh | ! l L ‘tT Leukemia O.8210°%x 252 2,107 */rad Solid Tumors 2x10°S2 402 8x O°/rad Total Risk (Mortality)= lG74/rad Ns] & Cancers All Other casatann. 2 ee wt . *e, ath mT = ZL/ |.eukemia om 2 ed “Pe, exernema vee hen axe aati O oct a 2 ‘S o~ 1G oe "e,5 , L ". . am cence apegonm ORE EREDID 20 30 Years After trradiation ‘. , &O SO Figure 3. Pretracted risk following a dose of ome rad, adapted from Sinclair “Risk es e Basis fer Radiation Pretection”, paper presented at 6th International Congress of the International - Radielogical Protection Association, in Berlin (West), May 7-12, 1984. 5904b4