Using the micronucleus assay to detect genotoxic effects of metal ions.

The lymphocyte micronucleus assay was used to measure the average frequency of micronuclei in a population and thus assess genotoxic effects. Data from 174 persons give an average value of 16.4 +/- 7.3, and a slight age-dependence was observed. To detect combined environmental mutagen injuries the micronucleus assay was used to study the effects of metal compounds. Cadmium ions increased the micronucleus frequency linearly after incubation with whole blood in vitro with 10(6)-10(-3) M concentrations for 30 min. Similarly, a linear increase in micronucleus frequency was detected with 10(-3)-10(-1) M mercury ions. Concerning the biological effect of selenium, it was found that neither sodium selenite nor selenium dioxide induced increases at concentrations of 10(-7)-10(-6) M; 10(-5) M caused a slight increase; 10(-4) M, however, destroyed the cells. These results suggest that the human lymphocyte micronucleus test can be used to assess genotoxic injuries due to environmental effects in human lymphocytes.