Determination of metals in cow's milk by flame atomic absorption spectrophotometry

The essential (Ca, Cu, Fe, Mg, Mn, Zn) and toxic metals (Pb and Cd) were determined by flame atomic absorption spectrophotometry (FA-AAS) in raw cow's milk. Milk was sampled four times in March 2000 on fifteen farms near Kriz in the Zagreb region from bulk milk directly into plastic bottles (to avoid contamination). The raw cow's milk samples were digested in an MLS-1200 Mega Microwave Digestion System with MDR Technology, and the metals were determined directly by FA-AAS in the solutions of digested samples. Statistical analyses were performed using statistical software SAS v. 8.0. Contents of essential minerals (Ca, Cu, Fe, Mg, Mn, Zn) in milk from Croatian farms are on the normal levels in comparison with the data from other countries. The level of toxic metals (Ph and Cd) was lower than the tolerance level defined by Croatian regulations (Pb < 100 mug/l and Cd < 10 mug/l).