Assessment risk to children's health due to consumption of cow's milk in polluted areas in Puebla and Tlaxcala, Mexico.

This study aimed to determine the heavy metal content in cow's milk produced in areas irrigated with waste water and to evaluate the health risk with daily consumption of milk for children. The sample consisted of four zones in which small farmers were selected and the milk of 160 cows in two seasons of the year. On average, the metals in the milk in decreasing order were 0.36; 0.046; 0.035; 0.029; 0.015; 0.012, and 0.002 mg kg-1 for Zn, Pb, As, Cu, Cr, Ni, and Cd, respectively. The Pb exceeded the limits allowed by Codex. The values shown in the hazard quotient for the As of more than 1 and HI were higher. On the other hand, the individual risk of cancer showed a descending order As> Cd> Cr> Pb, while the total risk indicated that the combined effect of metals put girls and boys at serious risk.