% CS ; Pooe fram a payer given by Gram last Octeber (Sanders, “2 Cl, 1970). Dr. “Bair and his colleagues have done the most relevant plutontumoxide inha~ - Jntion experiments. “Nontuifoen: ireadiation of the lung fram deposite radioactive particulates is clearly more carcinogenic than uniform expocure (on a total-luny dose basis), and alpha-irradiation is more carcinogenic than beta-irradiation. The doses required for a substantial tumor incidence, are very high, how ever, if measured in proximity to the particle; and, again, there are no data to establish the low-incidence end of a dose-effect eurve. And there is no general theory, or data on which to base a theory, which would perrait extrapolation of the high incidence por- tion of the curve into the low incidence region. " Tagree and I sugges that in sucha circumstance it is epppropriate to view the standar‘ds with extreme caution. There is another ha.zardous aspect of the particulate pe oblem in which suostantial uncertainty exists. In case of an acrosol depositing an a surface, the mate:‘ial may be resuspeended in the air. This process is crudely described by a quantity called a resuspension factor which is retyDORA SGPASK, ay, tue r, * 2 se markable in that it sccms cenerally known only te within a factor of bil- lions (Kaihren, R.L: .1988). Undoubtedly it can be pinpointed sornewhat 4 ~—y . w * 2-3 IE 5 te *. ere. + af see am oat. =. a %, better than this for plutonium oxide, but the handiest way to dispatch the problern is lo say there is some evidence that plutonium particles become wttachad to larger particles and are lhercfora no longer potential accosols. Uiitss miunorely there is alco evidence that lacee particles goneraic acroy ? aaoue Turoutenes, ainbare lise blown abort raore readily, gad an s .