Preliminary investigation on the balance of lead and cadmium content in milk and its by-products.

Many studies have recently been devoted to the determination of lead and cadmium in milk, in view of the toxicity of these metals and the importance of milk in the diet of infants and children. Enrichment of lead and cadmium in fatty dairy products has been sometimes noted. A systematic study on milk and its primary products (skimmed milk, cream and cheese) obtained from the same batch of milk is considered in order to define a tentative balance of these two metals. Lead and cadmium were determined by atomic-absorption spectrophotometry with graphite furnace on a solution of the ashed sample. As a consequence of the appreciable interference due to the matrix effects, the method of standard additions was adopted to determine the metals in few samples with a statistically acceptable degree of accuracy and precision. The range of the lead and cadmium content found in these products is comparable with recent literature data concerning uncontaminated samples.