6. Recommendatcies: It is urged that the U.S. Favironmental Protection Agency consider and act upon each of the following recommendations which are called for (a) in order to provide an improved basis for the assessment of health risks and standards for plutonium and other actinides and (b) to provide a higher degree of protection from the effects o tty internal eipha emitters fer occupational groups and the general public by acopting more conservative interim standards for plutonium exposure. (1) Initiate a comprehensive interagency research progrem to assess the health risks of inhaled alpha emitting particles, with special attention to both "hot" particles and insoluble particles of low activity Ms af re ae ° 7 per particle (Some pertinent studies have been proposed to the EPA (2) Conduct a comprehensive epidemiological health study of all past and present plutonium workers, and of all other groups which have been exposed to the inhalation of plutonium at levels significantly above fallout plutoniun. (3) Call upon the National Cancer Institute and the National Heart and Lung Institute to apply an appropriate fraction of their resources to . assess the role of inhaled alpha emitting particles on the incidence of human cancer and heart disease. i (4) Adopt more conservative occupational standards for plutoniun. A reduction of present air concentration and lung burden standards by a factor between 100 and 1000 appears to be in order. Better protection should be provided for younger employees and groups exposed to possible inhalation of finely divided and higher specific activity plutonium. (5) Maiatain public exposure levels of plutonium. and other alpha emitters to the practical mininum. In my view this would limit public exposure to airborne dusts not exceeding 0.5 picocurtes of alpha activity (about one alpha disintegration per minute) per gram of nitric acid insoluble hy wegPhe Spe