Kids Near a Mine Had IQs 12 Points Lower From Heavy Metals

Children living near a mining site in Peru had six times more lead in their hair and scored 12.3 IQ points lower than children who weren't exposed. That's the difference between average and below-average intelligence.

What the Study Found

A 2026 study in Forensic Sci Int compared children living near the Cerro de Pasco mine in Peru to unexposed controls. They measured metals in hair and tested cognitive development.

Exposed children had 6 times more lead, 3 times more arsenic, and double the cadmium of unexposed children. Their mean total IQ was 12.3 points lower. Lead, cadmium, arsenic, manganese, and antimony all correlated with lower IQ scores.

Getting Worse Before Getting Better

Hair metal concentrations in the exposed children spiked 200% between 2016 and 2018. By 2021, levels dropped but still remained above 2016 concentrations. The mine keeps contaminating, and the children keep absorbing it.

Why This Matters Beyond Peru

Mining communities exist worldwide. Children near mining operations, smelters, and industrial sites face similar exposures. Lead alone has no safe level for children's brain development. Combined with arsenic and cadmium, the neurotoxic burden multiplies.

What Parents Can Do

If you live near industrial sites, test your children's blood lead levels. Filter drinking water. Wet-mop floors to reduce dust. Wash hands frequently. Grow food away from contaminated soil. Check out non-toxic baby products for safer everyday items.

Also see glass food storage for safer alternatives.

Source: Carreiro-DaCunha E, et al. (2026). Forensic Sci Int.