Kinetics of introduction of micronucleated polychromatic erythrocytes in bone marrow and peripheral blood following subchronic microwave exposure

The aim of this study was to investigate the induction kinetics of micronucleated polychromatic erythrocytes (MNPCEs) in bone marrow (BM) and peripheral blood (PB) of rats during intermittent subchronic exposure to selected radiofrequency microwave (RF/MW) radiation. Rats were exposed to RF/MW 2.45 GHz, power density 5-10 mW/cm2 2 hours a day, 7 days a week. The specific absorption rate (SAR) was 1.25±0.36 W/kg. The study included control groups. After the animals were killed, BM and PB smears were supravitally stained and MN frequency was recorded for both PB and BM by scoring 1000 PCEs/slides. The results were analysed using StatSoft 95 package. In comparison with controls, the MN frequency in BM significantly increased on experimental day 15. BM MN frequencies were elevated in each experimental phase. The incidence of MNPCEs in PB significantly increased after eight two-hour exposures. From that point on, MNPCEs declined to reach control values by the end of the experiment. These findings could indicate radiation effects on BM erythropoiesis and their reflection on PB. The kinetics MNPCE induction in BM and PB of irradiated rats revealed a complex chain of events, including temporary imbalance in erythrocyte maturation and/or proliferation processes, followed by a feedback mechanism of the homeostatic control system, and possible elimination of MNPCEs from PB by mononuclear phagocytes. This points to an adaptive mechanism in rats in response to experimental subchronic RF/MW exposure.(author)