Effect on peripheral blood chromosomes

A survey of investigations on chromosome aberrations in peripheral blood lymphocytes of people exposed to elevated levels of radon in the atmosphere shows non linear dose relationship. At very low doses a sharp increase occurred, followed by a plateau. A hypothesis involving DNA repair mechanism is given. In vivo the doses are always not only due to internal alpha but also due to the external gamma irradiation, which must be taken into account, especially in the low dose range. Therefore in vitro experiments with alpha particles of radon daughters at doses comparable to the in vivo investigations have been carried out (0.05 to 3 mGy). The method is described. Preliminary results show similar dose response as at our in vivo studies