Cigarette smoke exposure of school children: effect of passive smoking and vitamin E supplementation on blood antioxidant status.

Despite similar vitamin E concentrations, erythrocytes of 25 children of smoking parents had an increased tendency (p < 0.01) to peroxidize in vitro as compared with those of 28 children of nonsmoking parents. This difference was abolished by vitamin E supplementation (100 mg alpha-tocopherol acetate/day for 14 days). The increased susceptibility to erythrocyte peroxidation in the smokers may reflect lower erythrocyte glucose-6-phosphate dehydrogenase, glutathione peroxidase and superoxide dismutase activities (p < 0.001, p < 0.005, and p < 0.02, respectively) in children of smoking parents. Children of smoking parents seem to be under sustained oxidant stress with increased plasma-conjugated dienes (p < 0.01) and dehydroascorbate (p < 0.002) concentrations. Total plasma cholesterol was similar in children of smoking and nonsmoking parents, and was unaffected by vitamin E supplementation. Indices of sustained oxidant stress in children of smoking parents were partially ameliorated by vitamin E supplementation.