This report assesses the levels and effects of exposure to ionizing radiation. Scientific findings underpin radiation risk evaluation and international protection standards. This report comprises a report with two underpinning scientific annexes. The first annex recapitulates and clarifies the philosophy of science as well as the scientific knowledge for attributing observed health effects in individuals and populations to radiation exposure, and distinguishes between that and inferring risk to individuals and populations from an exposure. The second annex reviews the latest thinking and approaches to quantifying the uncertainties in assessments of risk from radiation exposure, and illustrates these approaches with application to examples that are highly pertinent to radiation protection.

DDT is a pesticide that was once widely used to control insects. Both DDD and DDE are breakdown products of DDT. This profile includes: (1) The examination, summary, and interpretation of available toxicologic info. and epidemiologic evaluations on DDT/DDD/DDE to ascertain the levels of significant human exposure for the substance and the associated chronic health effects; (2) A determination of whether adequate info. on the health effects of DDT/DDD/DDE is available to determine levels of exposure that present a significant risk to human health of chronic health effects; and (3) Identification of toxicologic testing needed to identify the types or levels of exposure that may present significant risk of adverse health effects in humans. Illus.