Radiation Carcinogenesis in Experimental Animals and Its Implications for Radiation Protection

SummaryCancer induction is generally considered to be the most important somatic effect of low doses of ionizing radiation. It is therefore of great concern to assess the quantitative cancer risk of exposure to radiations of different quality and to obtain information on the dose-response relationships for carcinogenesis.Tissues in the human with a high sensitivity for cancer induction include the bone marrow, the lung, the thyroid and the breast in women. If the revised dosimetry estimates for the Japanese survivors of the atomic bomb explosions are correct, there is no useful data base left to derive r.b.e. values for human carcinogenesis. As a consequence, it will be necessary to rely on results obtained in biological systems, including experimental animals, for these estimates.With respect to radiation protection, the following aspects of experimental studies on radiation carcinogenesis are of relevance:(1) Assessment of the nature of dose-response relationships.(2) Determination of the relative biolo...