Teet em ee ee omen - 39 - . Positive counts were obtained for 14 of 21 persons measured. These counts suggested chest burdens ranging from 3 to about 10 nCi. However, in no case did the estimated cnast burden exceed the MDA at the 95% con- fidence level. Seven of the 14 subjects with positive chest counts had estimated chest burdens of 7 nCi or greater and mav be considered (at the 68% level of coniidence) to have statistically significant chest buréens of from 7 to 10 nci.68 Since the plutonium is still in the lung cavity, 27 vears in tne o= Pp. sost-exsccsure, it 15 correct to assume that it was initially insolunle form and hence pertinent here. this measurement, however, most of exvectec to be in the lymoh noces. 69 At the time the material would bea Nevertheless, we coulda particle burden in these subjects fron tnese G€ai2 if we xnew the initial particle size at the time Tne nature This particle size Gata is unavailable. ~~ ison. of the contaminating events suggest that the particle size micnt nave been somewhat larger than those tnat result from oslucsnium fires where most of the respirable activity resiaes on particles in the size range of 0.1 u to 2.3 u in diameter. Much of the contamination of the 43/ [JOPP Dublicarion 19, The Piuconitum and Qcnar Actnides, “3/ Mann, d.R. and A.R. Netabolisn of Comsounds oF Pergamon Prass, Mew York, 1372, Kirchner, Oo. cit., p. 880. p. 7.