Abnormal erythrocyte-related parameters in children with Pb, Cr, Cu and Zn exposure

The link between exposure to a particular heavy metal or metalloid and the development of anemia is well established. However, the association between combined exposure to multiple heavy metal(loid)s and anemia in children is still lacking in evidence. In this study, a total of 266 children aged 3 to 7 were recruited from Guiyu, China. Inductively coupled plasma mass spectrometry (ICP-MS) was used to measure blood heavy metal(loid) concentrations. Blood cell count, hemoglobin (HGB), mean corpuscular hemoglobin (MCH), mean corpuscular volume (MCV), mean corpuscular hemoglobin concentration (MCHC), hematocrit (HCT), and red blood cell distribution width (RDW) were measured by an automated hematology analyzer. Erythrocyte-related parameters were negatively correlated with the Cu and Cu/Zn ratios and positively correlated with Cr, Ni, Zn, and Se by Spearman correlation analysis. Only blood Cu level was negatively correlated with HGB [β = −2.74, (95% Cl: −4.49, −0.995)], MCH [β = −0.505, (95% Cl: −0.785, −0.226)], MCV [β = −1.024, (95% Cl: −1.767, −0.281)], and MCHC [β = −2.137, (95% Cl: −3.54, −0.734)] by multiple linear regression analysis. The Bayesian Kernel Machine Regression (BKMR) model analysis indicated a negative correlation between the combined exposure to Cu, Zn, Pb, and Cr and MCH and MCV. The single-factor analysis showed a considerable statistical difference only with Cu on MCV, MCH, and HGB. Furthermore, the interaction analysis highlighted the interdependent effects of Cu and Zn, Pb and Zn, and Cr and Zn on MCH and MCV levels. Additionally, the oxidation and/or antioxidation reactions may play a significant role in the development of metal(loid)-induced anemia risk. It is crucial to investigate the effects of co-exposure to multiple heavy metal(loid) elements on anemia, especially the interrelationships and mechanisms among them.