Reduction of heavy metals (Cd, Cr, Hg and Pb) in dairy products from areas near mining pollution, to protect food safety

Cayo Barrionuevo R.A.; Guerra Lima R.; Llanos Condori J.A.; Cotacallapa Ochoa K.L.; Torres-Cruz E. · Nutricion Clinica y Dietetica Hospitalaria (2026) · DOI: 10.12873/461etorres

Resumen

Introduction: Heavy metal contamination represents a risk to food safety in regions influenced by mining activities, where milk and its derivatives may act as vehicles of human exposure to cadmium (Cd), chromium (Cr), mercury (Hg), and lead (Pb). Objective: To evaluate the presence and reduction of heavy metals in milk, fresh cheese, whey, and cream from areas affected by mining activities and inadequate mine closure in the LLallimayo basin (Peru), using skimming and adsorption with activated carbon, from a food safety perspective. Methodology: An experimental study was conducted on dairy products collected in the Puno region. A mechanical skimming pretreatment and an adsorption process in fixed-bed columns with activated carbon were applied, evaluating two bed heights (10 and 20 cm). Concentrations of Cd, Cr, Hg, and Pb were determined using X-ray fluorescence (XRF). Results: Increasing the bed height improved removal efficiency across all matrices. Whey showed the highest reduction of metals, achieving complete removal of Pb, while milk showed high removal of Cr and fresh cheese showed the greatest reduction of Cd. Cream concentrated the highest metal loads, confirming the affinity of metals for the lipid phase. Conclusion: The combination of skimming and adsorption with activated carbon is a viable and low-cost alternative for reducing heavy metals in dairy products, contributing to food safety and the protection of public health in areas affected by mining contamination.

Instituciones: Universidad Nacional del Altiplano