Molecular and cell models of biological effects of heavy ion radiation.

Many quantitative models have been developed for the biological effectiveness of radiation of different quality. They differ substantially in their assumptions, and a lack of firm knowledge remains as to the detailed nature of the critical early molecular damage. Analyses of microscopic features of the stochastic structures of radiation tracks have led to hypotheses on the importance of clustered damage in DNA and associated molecules. Clustered damage of greater complexity or severity is suggested to be less repairable and therefore to dominate the biological consequences.