This report is a review of the draft feasibility study that was issued at the request of Congress by the Centers for Disease Control and Prevention CDC and the National Cancer Institute NCI Over 500 atmospheric nuclear weapons tests were conducted at various sites around the world during 1945 1980 As public awareness and concern mounted over the possible health hazards associated with exposure to the fallout from weapons testing a feasibility study was initiated by CDC and NCI to assess the extent of the hazard The CDC NCI study claims that the fallout might have led to approximately 11 000 excess deaths most caused by thyroid cancer linked to exposure to iodine 131 The committee noted that CDC and NCI used the best available data to estimate exposure and health hazards The committee does not recommend an expanded study of exposure to radionuclides other than 131I since radiation doses from those radionuclides were much lower than those from 131I It also recommended that CDC urge Congress to prohibit the destruction of all remaining records relevant to fallout