Determination of Zn, Pb, Cd and Cu contents in raw milk from Khorram-Abad dairies

Heavy metals are the most important chemical pollutants of foods. Milk and dairy products due to the nutritional functions are largely consumed by infants and children around the world. The purpose of this study was to analyze Zn, Pb, Cd and Cu contents in raw cow milks produced in dairies of Lorestan industrial livestock zone during 2014. A total of 24 milk samples was collected from eight dairies. The samples were subjected to acid digestion according to standard method. Afterwards, the metal contents were determined using ICP-OES. All statistical analyses were performed using the SPSS statistical package. The results showed that mean concentrations of Zn, Pb, Cd and Cu in milk samples were 3072±674, 2720±2790, 104±18.5 and 142±149 µg/kg, respectively. Also comparison of the mean concentrations of the metals with the WHO maximum permissible limits in milk revealed that the mean concentrations of all metals were significantly higher than permissible limits. Because of the mean concentrations of Zn, Pb, Cd and Cu in milk samples were higher than Mean Residual Limits, therefore to achieve the consumers’ safety, monitoring of feed intake, water supplies, soil properties around livestock and forage crops and control of pollutants emission from industries near the livestock are recommended.