Milk is a complete food useful to promote growth and development of the infant mammals as it contains vital nutrients including proteins, essential fats, vitamins, and minerals, in a balanced proportion. Milk can also contain chemical hazards and contaminants, such as heavy metals which can be a risk for health. This study was aimed at determining the level of the heavy metals in cow’s milk collected from Butajirra and Meskan districts, south Ethiopia. Cows’ milk was collected from 193 healthy and lactating cows. Samples were digested by optimized microwave digestion method using HNO 3 and H 2 O 2 . Analysis was done using ICP-OES for Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn. MP-AES was used for Ca, Mg, K and Na.
Ni was not detected in all the milk samples. The concentrations of metals in the studied milk samples were, Cd (0.0 – 0.03), Cr (0.0 – 0.4), Cu (0.03 – 1.1), Fe (0.0– 1.9), Mn (0.0– 0.7), Pb (0.0– 12.3), Zn (0.0–8.2), Ca (380.1– 532.4), Mg (159.6– 397.9), K (1114.2–1685.8) and Na (495.9–1298.3) ppm. These values were compared with guide lines of different international organizations for food and other available literatures. Cd, Cr, Cu, Mn, Pb, Zn and Mg were found over the permissible limits.
Special attention should be given to the level of heavy metals in cows’ milk, since they are difficult to remove from the body and are dangerous to health once they accumulate to a level greater than their limit.