- 31 a burden range of 0.5 uCi fluctuated between 0.04 | - to 50 uCi the observed tumor incidence 51 and 0.37”. All of these lung cxperiments involved intense exposures and a significant level of carcinogenesis. Severe damage and disruption of tissue were associated with the exposures. The most relevant lung experiment is Bair's Pu 3905 inhalation study with beagles>*7 4, Exposure was to particulates of 0.25 u or 0.5 u median diameter; burdens were in the uCi range. Twenty of the 21 dogs that survived more than 1600 days post exposure had lung cancer. cancers were multicentric in origin. Many of these The cancers again appeared in conjunction with severe lung injury. natural incidence of the disease is small, Since the it appears that at this level of exposure the induction of lung cancer is a certainty during the normal beagle life span. S1/ Cember, H., Op. cit. $2/. Bair, W.J., J.F. Park, and W.J. Clarke, At the same , “Long-term study of inhaled plutonium in dogs," Battelle Memorial Institute (Richland), AFWL-TR-65-214, 1966 (AD-631 690). 593/ Park, J.F., W.J. Clarke and W.J. Bair, "Chronic effects of inhaled 239pPu02 in beagles," Battelle-Northwest Laboratory Annual Report for 1967 to the USAEC Division of Biology and Medicine, Vol. I, Biological Sciences, BNWL-714, 1968, pp. 54/ 3.3-3.4. Park, J.F., et al, "Progress in Beagle Dog Studies with Transuranium Elements at Battelle-Northwest," Health Physics, Vol. 22, No. 6, June 1972, pp. 803-810. ome ST ne Tt om et. Peefagear pet x ‘= oe * wn é ' son .