Evaluation of the cytotoxicity and the genotoxicity induced by α radiation in an A549 cell line (original) (raw)

Exposure to radon and its progenies represents one of the greatest risks of ionizing radiation from natural sources. Nowadays, these risks are assessed by the extrapolation of biological effects observed from epidemiological data. In the present study, we made a dose response curve, to evaluate the in vitro response of A549 human lung cells to a-radiation resulting from the decay of a 210 Po source, evaluated by the cytokinesis blocked micronuclei assay. The clonogenic assay was used to measure the survival cell fraction. As expected, the results revealed an increase of cellular damage with increased doses made evident from the increased number of micronuclei (MN) per binucleated cell (BN). Besides this study involving the biological effects induced by direct irradiation, and due to the fact that radiation-induced genomic instability is thought to be an early event in radiation carcinogenesis, we analyzed the genomic instability in early and delayed untargeted effects, by using the medium transfer technique. The obtained results show that unirradiated cells exposed to irradiated medium reveal a higher cellular damage in earlier effects when compared to the delayed effects. The obtained results may provide clues for the biodosimetric determination of radon dose to airway cells at cumulative exposures.