I. Biological implications of radiation

This paper deals principally with the potential late effects of radiation. It also covers briefly some cellular effects of radiation and the early effects of radiation on man. There is an obvious difference between the early and late effects of radiation. Doses delivered at low dose rates were compared to the same doses delivered at high dose rates in a number of biological systems. Radiation can be harmful and even lethal if delivered at high doses and dose rates. As one goes down to very low doses and low dose rates, there are no observable effects. With respect to possible radiation exposure risks from power reactors, with routine reactor operations, one would not expect to detect any effect as a result of that exposure. Bile acids labelled with stable isotopes may be used for determination of bile acid kinetics with an isotope dilution technique. Details of methodology using deuterium and carbon 13 are discussed.