OXIDATIVE STRESS-INDUCED BY ENVIRONMENTAL TOBACCO-SMOKE IN THE WORKPLACE IS MITIGATED BY ANTIOXIDANT SUPPLEMENTATION

Environmental tobacco smoke (ETS) is a pervasive contaminant in the wo rkplace, Previous studies by this laboratory have shown that exposure to workplace ETS results in increased oxidative stress and damage, as measured by increased levels of the antioxidant enzymes superoxide dis mutase, catalase, glutathione reductase, and glutathione peroxidase. 8 -Hydroxy-2-deoxyguanosine, a marker of oxidative DNA damage, was also 63% greater in the exposed group compared with controls. Subjects in t he previous study who reported workplace exposure to ETS were given a 60-day supply of an over-the-counter antioxidant formulation consistin g of 3000 mu g of beta-carotene, 60 mg of vitamin C, 30 I.U. of alpha- tocopherol, 40 mg of zinc, 40 mu g of selenium, and 2 mg of copper, Af ter the 60-day supplementation period, blood samples were again drawn, and the results,were compared with the presupplementation values. A 6 2% decrease in 8-hydroxy-2-deoxyguanosine was observed after supplemen tation. Lipid peroxidation levels were also decreased, as were the ant ioxidant enzyme activities. The biochemical evidence suggests that exp osure to ETS in the workplace increases oxidative stress and that anti oxidant supplementation may provide some protection.