Since its establishment in 1955 the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR)' has reported yearly to the General Assembly and at irregular intervals has submitted more comprehensive reports with detailed scientific annexes. This is the eighth in the series of such substantive reports.2 It consists of a summary and a main text outlining the conclusions reached in the Committee's discussions and twelve scientific annexes reviewing in considerable detail the procedures and the scientific information on which such conclusions rest