The effects of some boron compounds against heavy metal toxicity in human blood.

Heavy metals can accumulate in the environment and cause serious damages to ecosystems and human health. Boron is considered to be essential micronutrient with its well established biological functions and the antioxidant effects of boric acid (BA) are controversial. However, the potential of important boron compounds in cellular activities remains unexplored. Therefore, we aimed to assess the efficacies of some boron compounds (BA, borax, colemanite and ulexite) on the genotoxicity induced by heavy metals (arsenic trioxide, colloidal bismuth subcitrate, cadmium chloride, mercury chloride and lead chloride) in human blood cultures. For this aim, sister chromatid exchange (SCE) and micronuclei (MN) assays were performed to establish DNA damages in lymphocytes. Besides, oxidative stress was monitored by estimating the changes of main antioxidant enzyme activities and the levels of total glutathione (TGSH) in erythrocytes. The present study showed that heavy metal treatments increased the frequencies of SCE and MN and the plasma malondialdehyde (MDA) level; decreased the antioxidant enzyme activities and the level of TGSH compared to controls. Whereas, the tested boron compounds (5-20 ppm) significantly reduced the genotoxic effects induced by low doses of heavy metals. Our results revealed that the protective roles of boron compounds occurred with the effectiveness on their anti-oxidant capacity. In conclusion, these compounds could be useful in the development of functional food and raw materials of medicine.