Additivity test for composition of binomial effects in chromosome aberrations after radiation injury

Additivity of clastogenic effects of two doses of radiation to human peripheral blood lymphocytes is considered. We compare the effects of combined tritium and gamma irradiation with the sum of the effects of either irradiation administered separately. Our solution is based on combination of de Moivre and Cramèr-Slucky theorems. The results for 14 subjects where the deletion types of chromosome aberrations were counted indicate a Normal distribution of the sample additivity index, oscillating non-significantly around zero, with one outlier towards adaptivity and another towards synergism of the effect of the two doses absorbed by the cells.