Potential oxidative stress in the bodies of electric arc welding operators: effect of photochemical smog / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate whether photochemical smog emitted during the process of electric arc welding might cause oxidative stress and potential oxidative damage in the bodies of welding operators.</p><p><b>METHODS</b>Seventy electric arc welding operators (WOs) and 70 healthy volunteers (HVs) were enrolled in a randomized controlled study design, in which the levels of vitamin C (VC) and vitamin E (VE) in plasma as well as the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), and the level of lipoperoxide (LPO) in erythrocytes were determined by spectrophotometry.</p><p><b>RESULTS</b>Compared with the average values of the above experimental parameters in the HVs group, the average values of VC and VE in plasma as well as those of SOD, CAT and GPX in erythrocytes in the WOs group were significantly decreased (P < 0.005-0.0001), while the average value of LPO in erythrocytes in the WOs group was significantly increased (P < 0.0001). The findings from the partial correlation analysis on the controlling of age suggested that with a prolonged duration of exposure to photochemical smog the values of VC, VE, SOD, and GPX, except for CAT, in the WOs were decreased gradually (P < 0.05-0.005), the value of LPO in the WOs was increased gradually (P < 0.001), and that with the ozone dose increased in the air in each worksite VC, VE, SOD, CAT and GPX decreased (P < 0.005-0.001), but LPO increased (P < 0.001). The findings from the reliability analysis for the VC, VE, SOD, CAT, GPX, and LPO values which were used to reflect oxidative stress and potential oxidative damage in the WOs showed that the reliability coefficients' alpha (6 items) was 0.8021, P < 0.0001, and that the standardized item alpha was 0.9577, P < 0.0001.</p><p><b>CONCLUSION</b>Findings in the present study suggest that there exists an oxidative stress induced by long-term exposure to photochemical smog in the bodies of WOs, thereby causing potential oxidative and lipoperoxidative damages in their bodies.</p>

Ozone emitted during copying process--a potential cause of pathological oxidative stress and potential oxidative damage in the bodies of operators / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To estimate the impact of copying on the indoor air quality, and to investigate whether ozone emitted during such a process induces pathological oxidative stress and potential oxidative damage in the bodies of operators.</p><p><b>METHODS</b>67 copying operators (CO) and 67 healthy volunteers (HV) were enrolled in a random control study, in which levels of lipoperoxide (LPO) in plasma and erythrocytes, and levels of vitamin C (VC), vitamin E (VE) and beta-carotene (beta-CAR) in plasma as well as activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) in erythrocytes were determined by spectrophotometric methods.</p><p><b>RESULTS</b>Compared with the HV group, the average values of LPO in plasma and erythrocytes in the CO group were significantly increased (P<0.0001), while those of VC, VE and beta-CAR in plasma as well as those of SOD, CAT and GPX in erythrocytes in the CO group were significantly decreased (P<0.0001). Pearson product-moment correlation analysis showed that with increase of ozone level in copying sites and duration of exposure to ozone, the values of LPO in plasma and erythrocytes in the bodies of operators were gradually increased,while those of VC, VE, beta-CAR, SOD, CAT and GPX were decreased in the same manner. Odds ratio (OR) of risk of biochemical parameters reflecting potential oxidative damage of the copying operators ranged from 4.440 to 13.516, and 95% CI of OR was from 2.113 to 34.061. Reliability coefficient (alpha) of the biochemical parameters used to reflect the potential oxidative damage of the operators was 0.8156, standardized item alpha=0.9929, P<0.0001.</p><p><b>CONCLUSION</b>Findings in the present study suggest that there exist a series of free radical chain reactions and pathological oxidative stress induced by high dose ozone in the operators, thereby causing potential oxidative and lipoperoxidative damages in their bodies.</p>