Effects of heavy metal mixture exposure on hematological and biomedical parameters mediated by oxidative stress

Background Heavy metal mixture pollution is currently a serious global environmental health concern. The toxicity of heavy metal mixture is mainly mediated by oxidative stress. However, the effects of heavy metal mixture exposure on hematological and biochemical parameters mediated by oxidative stress are unclear.Methods Our cross-sectional study had a final sample of 585 participants who were divided into exposure and non-exposure groups according to whether their areas of residence were near the ferroalloy factory. The assessment of internal heavy metal exposure markers was based on blood concentrations of chromium, lead, and manganese. Linear regression models were used to explore the relationships between heavy metal mixture exposure, hematological and biochemical parameters, and oxidative stress parameters. Furthermore, mediation analysis was conducted to evaluate the mediation effects of oxidative stress on the relationship between heavy metal mixture exposure and hematological or biochemical parameters.Results Compared with participants who were not exposed to heavy metal mixture, those who were exposed had greater levels of hematological (e.g., white blood cell and red blood cell markers) and biomedical (e.g., liver function markers, glucose, and lipid metabolism markers) parameters (p < 0.05), whereas levels of platelet markers were lower in participants who were exposed to heavy metal mixture (p < 0.05). We observed significant mediation effects of oxidative stress on the association between exposure status (exposure vs. no exposure group) and hematological parameters (e.g., red blood cell markers, platelet markers, and white blood cell markers) as well as biomedical parameters (e.g., liver function markers, glucose and lipid metabolism markers).Conclusion Heavy metal mixture exposure is associated with hematological and biochemical parameters, and oxidative stress potentially mediates this relationship.