Human biochemical response to ozone and vitamin E

Abstract

To determine whether vitamin E (dl ‐α‐tocopherol ) supplementation of the diet provides protection from inhaled oxidants such as ozone (O₃ ) in community air pollution, its effects were studied in healthy adult volunteers. Experimental groups received 800 or 1600 IU of vitamin E for 9 wk or more; control groups received placebos. Double‐blind conditions were maintained throughout the study. Biochemical parameters studied included red blood cell fragility; hematocrit and hemoglobin values; red cell glutathione concentration; and the enzymes acetylcholinesterase, glucose‐6‐phosphate dehydrogenase, and lactic acid dehydrogenase. No significant differences between the responses of the supplemented and placebo groups to a controlled O ₃ exposure (0.5 ppm for 2 h) were found for any of these parameters. The results indicate that vitamin E supplementation in humans, at the levels employed in this experiment, gives no added protection against blood biochemical effects of O ₃ in intermittently exercising subjects under exposure conditions simulating summer ambient air pollution episodes.