Lead (Pb) is highly toxic heavy metal that is detrimental to the food system. There are large mining and metallurgical companies in the central highlands of Peru that have been active for almost a century and contribute to air, water, and soil pollution, affecting food quality and causing damage to the environment and human health. Our study, conducted in 2018, assessed the content and transfer of lead in the soil-root-plant system in the high Andean grasslands in a geographical area near the metallurgical complex of La Oroya. Lead levels were measured in 120 samples of top soil (0–20 cm), roots, and grass shoots by flame atomic absorption spectroscopy. No significant differences were found between the soil pH, organic matter content, and lead among the samples evaluated (P > 0.05). Mean Pb concentrations decreased in the order of soil > root > shoot (P < 0.01) (212.36 ±  38.40, 154.65 ±  52.85 and 19.71 ±  2.81 mg/kg, respectively). The soil-to-root Pb bioconcentration factor, root-to-shoot translocation factor, and soil-to-shoot bioaccumulation factor values were 0.74 ±  0.26, 0.14 ±  0.06 and 0.10 ±  0.03, respectively. Lead in the soil was 3.03 times higher than the maximum limit for agricultural soil, and was 1.97 times higher than the value limit for fodder. Our findings are important and show that soils and pasture in this geographical area have high Pb levels due to metallurgical emissions that have been occurring since 1922. Such pollution negatively impacts health and the socio-economic status of the exposed populations.

Milk quality is affected by the concentration of lead (Pb) in soil and pasture grasses used to raise cattle, especially in areas near mining-metallurgical complexes. In this study, the Pb content of soil and its transfer to grass and dairy milk in an area located to 20 km from the La Oroya Metallurgical Complex in Peru (altitude, &gt;3700 m s.a.l) was measured. Twenty soil samples (0–30 cm depth), 20 grass samples were collected, and 0.5 L of milk was obtained from 20 lactating cow in the communal cowshed. The Pb concentration (mg/kg) was quantified by flame atomic absorption spectrometry using a commercial Pb standard as quality control. The Pb average concentration in the soil, grass, and milk samples were 217.81 ± 39.48, 20.09 ± 2.83, and 0.58 ± 0.018 mg/kg (p &lt; 0.01), respectively. The transfer factor (ratio of metal concentration) for Pb from soil to grass and from grass to milk was 0.095 and 0.031, respectively. The soil, grass, and milk samples all presented high Pb concentrations, with the milk samples containing 29-fold more Pb than the safety limit established by European regulations and were not suitable for human consumption or the manufacture of cheese, yogurt, and other derivatives. Our findings demonstrate that action to remediate these soils is critically needed.