Association between occupational lead exposure and plasma levels of selected oxidative stress related parameters in Jordanian automobile workers.

OBJECTIVES: To study any possible correlation between blood lead levels and some oxidative stress parameters of selected groups of lead-exposed automobile occupational Jordanian workers.

MATERIAL AND METHODS: Blood lead levels were determined for a total of 90 male automobile workers aged within the range of 25-45 years old along with the group of 20 agematched healthy males control. To get an idea about the antioxidant status of controls and lead-exposed workers, and to estimate the oxidative stress caused by exposure to lead, we measured the hydrogen peroxide (H₂O₂) concentration, superoxide dismutase (SOD) activity, lipid peroxidation as malondialdehyde (MDA) and total antioxidant capacity of controls and workers.

RESULTS: The study showed that lead levels in the case of workers were approximately 4-5 times as high as in controls 14.5-21 μg×dl^-1 vs. 4.3 μg×dl^-1, respectively. There was a significant decrease (16-25%) in the level of plasma reduced glutathione and 21-33% decrease in total antioxidant capacity (TAOC) in all worker groups, as compared to controls. The results showed that the concentration of malondialdehyde (MDA) in plasma was higher (120-333%) in the case of workers than controls being the highest in automobile electronics and the lowest - in mechanics. Furthermore, there was 149-221% increase in hydrogen peroxide (H₂O₂) concentration, and 26-38% increase in SOD activity in the case of workers compared to the control group.

CONCLUSIONS: There is a strong evidence for the associations between occupational lead exposure and various markers of oxidative stress in Jordanian automobile occupational workers. Thus, there is an urgent need to raise awareness and to initiate suitable protection guidelines for workers. Int J Occup Med Environ Health 2018;31(4):517-525.