Association between urinary heavy metal(loid)s exposure and dyslipidemia in children from e-waste dismantling areas

To assess temporal trends of urinary heavy metal(loid)s burden and lipid levels, and explore the single and joint associations of heavy metal(loid)s exposure with lipid profiles among children in Guiyu, a typical e-waste dismantling area in China. Based on 2016 and 2024 surveys in Guiyu, 197 children (aged 3-7) were enrolled. Urinary concentrations of 13 heavy metal(loid)s were determined using inductively coupled plasma mass spectrometry (ICP-MS). Serum lipid parameters including total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) were measured, and non-high-density lipoprotein cholesterol (non-HDL-C) was calculated. To investigate the independent and combined associations between metals and blood lipid profiles, multiple linear regression and Bayesian kernel machine regression (BKMR) models were employed. Urinary concentrations of Chromium (Cr), Nickel (Ni), Copper (Cu), Cadmium (Cd), and Lead (Pb) in 2024 were significantly lower than those in 2016 (all P < 0.05). In adjusted models, Manganese (Mn), Cobalt (Co), Cd, and Pb were positively associated with TC and non-HDL-C, while Cd and Pb were negatively associated with HDL-C (all P < 0.05). BKMR confirmed a significant joint positive effect of a 12-metal mixture on TC and non-HDL-C, and a negative effect on HDL-C. Despite decreased individual metal levels over the eight-year interval, the biological risk from co‑exposure to these metals remains a critical concern These findings highlight the need for vigilance regarding the synergistic cardiovascular toxicity of heavy metals on pediatric lipid homeostasis.