Monitoring of pesticide residues in milk consumed by the population of the State of Sao Paulo, Brazil, 2000 and 2002

Milk is an important constituent of human diet, and its consumption rate is high especially among children. Unintentional pesticide residues and their metabolites may be found in milk as a result from the consumption of water, grazing ground, and residues-containing foods by cattle, or from the use of pesticides on cattle for controlling ectoparasites. With the objective of evaluating the levels of these residues, 73 milk samples collected in 2000 and 2002 by the Sanitary Surveillance authorities from diverse commercial establishments in the State of Sao Paulo were analyzed. Pesticides analysis were carried out by means of gas chromatography and high performance liquid chromatography. Recovery studies were performed in order to assess the accuracy and the precision of the method. Recovery results ranged from 71 to 105%, all of them within the acceptable limits, with coefficients of variation from 1.2 to 17.8%. Quantification limit of the method was 0.01 mg/kg for hexachlorobenzene, alpha HCH, beta HCH, gamma HCH, aldrin, heptachlor, heptachlor epoxide, endosulfan I, endosulfan II, endosulfan sulfate, dieldrin, endrin, pp'DDE, pp'DDD, op'DDT, pp'DDT; and 0.02 mg/kg for lambda cyhalothrin, alpha cypermethrin and deltamethrin; and 0.10 mg/kg for carbendazin and thiabendazol. None of evaluated pesticides were found in any of the analyzed milk samples.