Emission-related Heavy Metal Associated with Oxidative Stress in Children: Effect of Antioxidant Intake

Abstract

Background: Heavy metals, the common pollutants emitted from industrial activities, are believed to cause harmful effects partially through the mechanism of elevated oxidative stress, and the antioxidant intake have been hypothesized to provide a potential protective effect against oxidative stress in human. Therefore, the objective of our study is to investigate the environmental exposure of heavy metals and the associated oxidative damage of young children living near a petrochemical complex and to assess the potential protective effect of dietary antioxidant intake. Methods: There were168 children recruited from the kindergartens near a huge petrochemical complex, with 87 as the high exposure group and 81 as the low exposure group. Urinary concentrations of eleven metals were detected by inductively coupled plasma mass spectrometry, and four biomarkers of oxidative stress were measured in urine samples by liquid chromatography-tandem mass spectrometry. The food frequency questionnaire was collected to assess participants’ intake of antioxidants. Multiple linear regression was performed to determine the significant predictors of metals for oxidative stress and to measure the potential beneficial effect of antioxidants. Weighted quantile sum regression was performed to determine the highest contributors among metals to the oxidative stress biomarkers. Results: Study subjects in high exposure grouphad significantly higher concentrations of chromium, manganese, nickel, arsenic, strontium, cadmium, and lead when compared to those in low exposure group. There was no obviously difference on the total antioxidant intake and dietary profile between the two groups.The elevated levels of two oxidative stress markers were significantly associated with most of the urinary metal concentrations in all study subjects after adjusting confounding factors, while no significant association was found between oxidative stress and antioxidant intake. Among the metals, mercury and strontium showed the dominated contributions for elevated levels of oxidative stress. Conclusion: Higher metal exposure were associated with elevated oxidative stress but with no protective affect by the antioxidant intake among the young children residents near a petrochemical industry.

“Assessing exposure of printing factory workers in thailand to selected heavy metals using urine and hair as non-invasive matrices”

“…LOQs were 0.0053, 0.0057, 0.0056, 0.006, 0.005, 0.028, 0.0377 and 0.0302 mg/L for Pb, Ni Cd, Cr, As, Mn, Hg and Co in urine and 0.0216, 0.0352, 0.0233, 0.0211, 0.0149, 0.4277, 0.0244 and 0.0105 mg/kg dry weight for As, Pb, Ni, Cd, Cr, Hg, Co and Mn in hair. Metals with concentrations below the LODs were replaced with onehalf of the LOD [36]. Each sample was tested in triplicate, and the relative standard deviation did not exceed 5% in any case.…”