[Cytogenetic effects in Allium schoenoprasum growing on the anthropogenically contaminated soil].

Cytogenetic effects in Allium schoenoprasum meristematic root tip cells grown for a year on the territory contaminated with 235U, 238U and 232Th decay series radionuclides, heavy metals and As were studied. The area is characterized with different concentrations of chemical compounds in soil affecting a toxic element migration in biocoenosis. Analysis of the chromosome aberration spectrum showed an ambiguous cell response to soil contamination. Within the weighted absorbed dose range up to 1.2 Gy the higher the dose the aberrant cell frequency increase was shown. But further increase in the dose resulted in a genotoxic effect decrease due to high toxic effects of heavy metals and radionuclides in soil. This was registered as a mitotic index decrease that can provoke a chromosome aberration frequency underestimation and result in erroneous conclusions about genotoxic effects in A. schoenoprasum used as a bioindicator.

Genotoxicity and cytotoxicity assay of water sampled from the underground nuclear explosion site in the north of the Perm region (Russia).

The results of our study revealed a local biologically relevant surface water contamination in the radionuclide anomaly in the north of Russia (Perm region) by means of Allium schoenoprasum L. anaphase-telophase chromosome aberration assay. This radionuclide anomaly was formed in 1971 as a result of an underground nuclear explosion with soil excavation. Specific activities of main dose-forming radionuclides in all examined reservoirs are below intervention levels officially adopted in Russia for drinking water. We found that (90)Sr significantly contributes to induction of cytogenetic disturbances. Our previous data and the data described here suggest that metal and radionuclide combined exposure (with the dose below permissible exposure limits for human) may cause substantial biological effects. These effects are in part due to synergic response. The findings described here indicated that development of a new concept of radiation protection for humans and biota should be based on the clear understanding of biological effects of low doses of radiation in chronic exposure to multi-pollutant mixtures.