Effect of Perinatal Multiple Exposures to Heavy Metals and Dioxins on Serum Steroids in Preschool Children—A Follow‐Up Study in an E‐Waste Contaminated Area in China

Taizhou City in Zhejiang Province was once one of China's largest e-waste-polluted areas. We assessed the effects of perinatal exposure to multiple heavy metals and dioxins on serum steroid levels in children from this area. We recruited 42 pairs of mothers and infants, collected breast milk and blood samples from the children, and detected dioxins and heavy metals in the breast milk, as well as steroid hormones in the serum. We employed multiple analytical approaches, including multivariable linear regression (MLR) model and Bayesian kernel machine regression (BKMR) models, to investigate the relationship between heavy metals, dioxins, and the serum steroid hormone levels in these children. In a separate exposure model using MLR, total polychlorinated dibenzofurans (PCDFs) (β: -0.930, 95% CI: -1.837, -0.023) and total polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDDs/DFs) (β: -0.578, 95% CI: -1.142, -0.013) were negatively associated with DHEA. Within the MLR mixed exposure model, a negative association was observed between cadmium (Cd) and progesterone (β: -0.225, 95% CI: -0.447, -0.004), while a positive association was found between 2,3,7,8-TeCDD (TCDD) and dehydroepiandrosterone (DHEA) (β: 0.841, 95% CI: 0.196, 1.485). However, based on the BKMR results, these associations were attenuated. Perinatal exposure to heavy metals and dioxins may disrupt sex hormone levels and may have an impact on later reproductive health.