Oxidative Stress Indices as Markers of Lead and Cadmium Exposure Toxicity in Auto Technicians in Ibadan, Nigeria

Abstract

Auto technicians (auto mechanics, panel beaters, battery chargers, and auto painters) are among the most valuable work force in the society. Reports on oxidative stress in persons occupationally exposed to mixed chemicals abound; however, few have narrowed down specifically on auto technicians, while even fewer have stratified the exposure in the different subgroups of auto technicians. This study evaluated the antioxidant status in auto technicians routinely exposed to lead and cadmium and stratified the results of exposure by different subgroups of auto technicians in Ibadan, Nigeria. Sixty-five apparently healthy males (aged 18 to 65years) were selected based on specific inclusion criteria using a structured questionnaire. Thirty-four were cases consisting of participants routinely working as auto technicians or apprentices(≥2years) while controls were thirty-one nonoccupationally exposed male members of staff/students of the University College Hospital, Ibadan, Nigeria. Blood was collected from all participants and analyzed for the presence of lead, total antioxidant capacity (TAC), and total plasma peroxides (TPP); oxidative stress index (OSI) was calculated. Urine samples collected from all participants were analyzed for the presence of urinary lead and cadmium using standard laboratory methods. Although values of TAC in cases (22538±8726.54) were not statistically different from what was obtained in controls (26741.87±8696.68), TPP and OSI were statistically higher in cases than in controls (183.88±53.39 and 120.16±70.54, respectively, and 0.93±0.45 and 0.49±0.33, respectively). The blood lead level in cases (10.11±4.47) was significantly higher than in controls (7.72±1.22) while elevated urinary lead and cadmium levels were observed in cases (0.65±0.21 and 0.34±0.11, respectively) compared to controls (0.52±0.19 and 0.27±0.10, respectively). Raised TPP and OSI levels—hallmark of active lipid peroxidation—found to be highest among panel beaters compared to others may be prognostic of membrane-damaging diseases in this subgroup of auto technicians.