ENVIRONMENTAL TOBACCO-SMOKE IN THE WORKPLACE INDUCES OXIDATIVE STRESSIN EMPLOYEES, INCLUDING INCREASED PRODUCTION OF 8-HYDROXY-2'-DEOXYGUANOSINE

Environmental tobacco smoke (ETS) is a pervasive contaminant in the wo rkplace. Our objective was to determine the oxidative stress effects o f ETS on employees who are exposed. The results provide information th at is useful to the resolution of risk assessment questions associated with ETS. We analyzed two blood draws from volunteers in our control and exposed groups. The level of exposure to ETS was determined throug h plasma cotinine measurements, which showed a 65% increase from the c ontrol group to the exposed group. Exposure to ETS resulted in a stati stically significant increase of 63% of the oxidative DNA mutagen 8-hy droxy-2'-deoxyguanosine in the blood of exposed subjects. This oxidati ve DNA damage has been linked to an increased risk of developing sever al degenerative chronic diseases, including coronary heart disease and cancer. The exposed subjects also had increased levels of superoxide dismutase, catalase, glutathione peroxidase (GPOX), and glutathione re ductase, However, these increases were only statistically significant in catalase and GPOX. Catalase levels were 13% higher in the exposed g roup, and GPOX levels were 37% higher in exposed volunteers. The bioch emical evidence suggests that exposure to ETS causes oxidative stress, resulting in DNA damage that may increase the risk of certain disease s.