RADIATION INDUCED CANCER IN ANIMALS

摘要

1. Studies in long-term surviving monkeys after relatively high doses of X rays have revealed a risk factor of 9 × 10~(-2) Gy~(-1) for tumour induction. A relatively high number of tumours in the kidney and brain were observed. These tissues are classified by the ICRP [6] with low tissue weighting factors.rn2. Dose-effect relations can be described by biphasic curves with maxima at doses of 4 to 8 Gy depending on the endpoint.rn3. High RBE values for tumour induction after neutron irradiation do not necessarily imply an extremely high risk factor for this radiation modality, but reflect more the low efficacy for tumour induction by low-LET radiation.rn4. Relative risks for radiogenic tumours in most rodent strains do not vary more than a factor of three for various neoplasms. The variation in tissue weighting factors for radiogenic tumours by a factor of 24 [5] and the correlation with various organs in experimental animals require a more sound scientific basis.