C3: -a‘ 6. Recommendations: It is urged that the U.S. Environmental Pretection Agency consider and act upon each cf the following recommendations which ave called for (a) in oxrder 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 protectior from the effects of internal alpha emitters for occupational groups and the general public by adopting 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 particlee of low activity per particle (Some pertinent studies have been proposed to the EPA (58) |) (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 plutonium. (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. , (4) Adopt more conservative eccupational standards for plutonium. .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 emplovees and groups exposed to possible inhalation of finely divided and higher specific activity plutonium. (5) Maintain public exposure levels of plutontum. and other alpha emitters to the practical minimun. In my view this would limit public exposure to airborne dusts not eaceeding 0.5 picocurtes of alpha activity (about one alpha disintegration per minute) per gram of nitric acid insoluble s4