Milk is an ideal food essential for newborns due to its composition and availability. In addition to its macronutrient, i.e. protide, glucide and lipids, milk also contains micronutrients, i.e. vitamins (A, D and B groups) and elements that are absolutely essential during the first months of a baby's life since it is the only source of nutrients 1. Milk contains several elements, which are essential or toxic such as cadmium, lead and nickel, due to these elements presence in the biosphere in general 2. Quantitation of essential and toxic trace elements in milk is an important analytical task, both for human health safety reasons and environmental bio-monitoring purposes. This requires elaboration and application of analytical methods of high sensitivity, selectivity and robustness. But the determination of trace inorganic constituents in milk is not a trivial task because of the complexity of the emulsion. Cow milk contains around 3.4 % of proteins, 2.8 % of casein, 3.7 % of fat and 4.6 % of lactose; additionally, the elements are present as different compounds that can affect both the sample preparation and the measurement strategies 3. Direct procedures for milk analysis were proposed using different spectro-analytical techniques. Each one presents some difficulties where Quinaia and Nobrega 4 , demonstrated that the presence of fat compounds affects the performance of the auto-sampler in graphite furnace