PRELIMINARY EVALUATION OF THE FACTORS INFLUENCING THE TRACE-ELEMENT CONTENT OF MILK AND DAIRY-PRODUCTS

As part of an overall monitoring programme launched by the Istituto Superiore di Sanita (Italian National Institute of Health) within the framework of the RAISA (Advanced Researches for the Innovation of Agricultural Systems) project sup ported by the National Research Council, an investigation was undertaken with the following goals: (i) assessment of the content of selected trace elements such as Al, Ba, Cd, Co, Cr, Cu, Fe, Rig, Mn, Ni, Pb, Pt, Sr and Zn in raw cow's milk and cheese; (ii) identification of possible correlations between animal feeding, year period of sample collection, environmental conditions and levels of elements in raw cow's milk; and (iii) evaluation of the influence of the manufacturing process on the concentration ranges of certain health-related elements in milk products. Quantitative determinations were carried out mainly by inductively coupled plasma atomic emission spectrometry. The results obtained show considerable differences among the levels of trace elements in raw milk samples collected during different periods of the same year. Furthermore, differences occur also among the trace element contents of raw milk and related products. All this provides evidence that animal feeding, year period of sample collection, environmental conditions and manufacturing processes all play a key role in the distribution of trace elements.