Daily intake of heavy metals by infants through milk and milk products

Concentrations of the essential elements Zn and Cu and potentially toxic elements Pb and Cd in different milk samples and baby food materials were measured, primarily to assess whether the intakes comply with recommended desired levels for essential and permissible levels for toxic elements. The geometric mean concentrations of Pb, Cd, Cu and Zn in different types of milk were found to vary from 1.70 to 3.35, 0.07 to 0.10, 43.2 to 195 and 1772 to 4230 μg/l, while the same in different baby foods had values from 39.5 to 77.7, 0.45 to 17.7, 1106.3 to 3157.3 and 9367 to 34 592 μg/kg, respectively. The concentration of Cd was found to be very low (0.1 μg/l) and fairly constant in all types of milk. The lead content in cow milk was observed to be the lowest even in comparison with breast milk. Concentrations of all these metals are approximately one order of magnitude higher in baby food products than those observed in different types of milk owing to higher fat content. The infant baby food Amul Spray contains low concentrations of toxic (Pb and Cd) and high concentrations of essential (Cu and Zn) elements. The daily intakes of Pb, Cd, Cu and Zn by infants through milk and baby foods marketed in Mumbai city have also been estimated. The daily intakes of Pb (1.1 μg/kg) and Cd (0.01 μg/kg) for infants through baby foods are well below the recommended tolerable levels of 3.57 μg/kg and 0.8–1.0 μg/kg, respectively. Similarly the daily intake levels of essential elements are also significantly lower than the recommended desirable levels of 3–5 mg and 0.5–1.0 mg for Zn and Cu, respectively. Milk from an Indian mother also does not provide adequate levels of essential elements to the infants and children.