Genotoxicity of sodium arsenite on the root tip cells of Vicia faba and Allium cepa

This study is concerned about an approach to evaluating the genotoxicity of sodium arsenite on the root tip cells of Vicia faba and Allium cepa by using the root tip micronucleus (MN) assay. As is known, arsenite is a kind of most ubiquitous environmental contaminants usually brought about by the large-scale mining or other industrial and agricultural activities. Epidemiological evidence reveals that long-term arsenic exposure may lead to occurrence of various human diseases and even cancers. On the other hand, broad bean ( Vicia faba L.) and common onion ( Allium cepa L.) are excellent plants for the assay of chromosome aberrations after chemical treatment. It is for this purpose that we have done a series of experiments to test the genotoxicity of sodium arsenite on the root tip cells of Vicia faba and Allium cepa. Our experimental results have shown that sodium arsenite is likely to induce MN formation in a concentration-dependent way, which is statistically different from the control (p0.05 and 0.01, respectively) of Vicia (0.3-10.0 mg/L) and Allium (1.0-30.0 mg/L) root tips after a 12 h exposure. In addition, arsenite is likely to cause the increase of cell-cycle length and decrease of concentration-dependent mitotic index. Thus, our research proves that Vicia and Allium root tip micronucleus (MN) assays can be used as a method for monitoring arsenic water contamination.