Inter-individual differences in radiation response shown by an in vitro micronucleus assay: effects of 3-aminobenzamide on x-ray treatment

Among the methods of biological dosimetry of ionizing radiation, the authors propose cytokinesis-block micronucleus assay for the measurement of individual dose absorbed. The dose-response curve was determined for in vitro-irradiated lymphocytes from 25 individuals. The dose-response relationship, fitted by the linear-quadratic function, was FMN = 0.015 (±0.0016) + 0.043 (±0.0075). D+0.083 (±0.0045).D2. Results are compared with those of other authors. 3-aminobenzamide (3AB) combined with X-rays was used to evaluate the micronucleus dose-response relationship in blood from 14 individuals. While it is known that 3AB inhibits poly(ADP-ribose) polymerase activity in vitro, they demonstrate that it also increases the X-ray-induced micronucleus yields. The resulting dose-response relationship varies from subject to subject. The possibility of using this approach to identify the individual radiosensitivity level is discussed. (author)