DNA damaging effects of sulfur dioxide derivatives in cells from various organs of mice.

The DNA-damaging effects of sulfur dioxide (SO2) derivatives (a mixture of sodium sulfite and sodium bisulfite, 3:1 M/M) in the cells of various organs (brain, lung, heart, liver, stomach, spleen, thymus, bone marrow and kidney) of male mice were studied using the single cell gel electrophoresis technique (SCGE). Three groups of six mice each received an i.p. dose of SO2 derivatives (125, 250 or 500 mg/kg body wt) daily for 7 days. A control group of six mice received 200 microl of normal saline i.p. daily for 7 days. Our results show that SO2 derivatives caused significant increases in olive tail moment (OTM) in cells from all organs tested in a dose-dependent manner. These results show that SO2 derivatives can cause DNA damage to multiple organs of mice and that SO2 derivatives are systemic DNA-damaging agents, not only to the respiratory system. It is suggested that SO2 derivative exposure has a potential risk to DNA in multiple organs of mammals and might be related to carcinogenesis or other diseases related to DNA damage. Further work is required to understand the toxicological role of SO2 and its derivatives on multiple or even all organs in humans and animals. Recent research results have shown that SO2 and its derivatives can also induce an increase in the frequencies of chromosomal aberrations, sister chromatid exchanges and micronuclei in mammalian cells and cause oxidative damage in multiple organs of male and female mice. Taken together, these results suggest that SO2 and its derivatives are systemic toxic agents. However, further studies need to be performed before a definitive conclusion can be drawn.