- 33 Laskin, et al, indicate a significant carcinocenic response in the luna at 1400 of lung tissue?®. rem, succesting a comparable sensitivity Geesaman indicates that the tissue revair time in the lung is of the order of one year’, It therefore seems aDprooriate, Sut not necessarily conservative, to accept as guidance that tnis enhanced cancer risk occurs when particles irradiate tne surrounding lune tissue at a dose rate of 1000 rem/yr or more. . 58 19090 raemn/vear to the Surrounding Lung Tissue Particle Activity ee {oCi) Particle Diameter 239... Prd5 2383.., Put? 3/4 max initlsczed (138 alveoli} 0.14 0.3 0.12 1/2 max inflated ( 63 alveoli) 0.07 0.5 0.93 0.02 0.4 0.06 Closest 29 alvacli id Laskin, 57/ Geesaman, Donali >., UCPrL-50387, Co. Cit, 3- 33." Tbid 33 37/ NA wwe @2 41, 23. cit. =e: i <4 Jepdees 1° iOy Based+.uron sracitic activity given ate —_- —-e y we ” ’ \. Laniznan wanaisl, ll. teh, » ‘ (1)