- To these comments, the comments " . of . Dr. A. 21- referenced by Geesaman, B. can be added Long: there is an urgent need to dispell the sense of security and certainty that the present limits for the maximum permisslvle lung burden and permissible air ccncentration bring . . the maxviman . the public should be informed of the uncertainties that exist. in these Vi. limits." Biological Data Related to Cancer Risk from Insoluole Plutonium Particles We have shown that insoluble alpha-emitting particles result in intense but localized radiation. They can irradiate We said that the available biological data strongly suggest i" at very high doses without being organism- or organ fatal. that a DF=1 grossly underestimates the DE for insoluble particulates of Pu-239, and consequently, the derived standards MPLB and MPC. for this radionuclide are greatly in error. We now turn to the experiments involving cancer induction é . by intense local exposure, , since these F ‘ are especially relevant in judging whether or not insoluble alpha-emitting particles constitute a unique risk. Geesaman collected and analyzed the pertinent experiments, and what follows 32/ Long, A.B-, Op. cit., p. 73. we ae re eyemrooes , . my »* . : . — Ca . ST cesT Tyee Btn ae a cy ~ ma .s ale : . wk . oe a Pea tae a8 Ta v rt otite 4 ‘o bot oe a oat BAN § Se' oe oe 2B os raed ‘ Oe rh he: oP aes pant . oye . ‘ . ' al ft < wae ‘pHG. pele1+ Arp ae T Be, a3 r, “ or, Be eg veh - ates “SPT [ta arepak oT gi