Figure 6.

Induction of micronuclei (a), binucleated and multinucleated cells (b) after 24 h incubation of A549 cells. After 24 h in culture, logarithmically growing A549 cells were treated with arsenite, MMA^III, DMA^III, thio-DMA^V, MMA^V, or DMA^V for 24 h; cells were fixed, stained and finally analysed by fluorescence microscopy as described in Materials and Methods. (a): additionally induced micronuclei, micronuclei level in control was 27 ± 3; (a, b): shown are mean values of at least three independent determinations + SD; statistically significant different from nonarsenic exposed controls: *P < 0.01 as determined by Student's t-test.