Lead and cadmium blood levels and transfer to milk in cattle reared in a mining area.

The presence of heavy metals in milk is a public health problem that negatively effects human health, especially infant health. This study evaluated the concentration levels of lead (Pb) and cadmium (Cd) in blood and its transfer to the milk of 20 cows in production in a rural community near the La Oroya Metallurgical Complex in Peru, which has emitted fine particulate matter for more than 90 years. Validated protocols were used for sample collection.