[Residues of organochlorine insecticides in human and bovine milk in Colombia].

Studies carried out in various countries have determined the presence of organochlorine insecticides in human and cow's milk. To quantify this contamination in Colombia, the concentrations of these insecticides were measured in 170 samples of milk from lactating mothers in Bogotá (105 samples) and three agricultural areas where fumigation is done frequently (65 samples). Also, for purposes of comparison, the study included 75 samples of fresh cow's milk, 10 samples of pasteurized milk, and 10 samples of whole powdered milk. In all the samples of human or cow's milk, high concentrations of total DDT were found. In some samples there were also appreciable amounts of benzene hexachloride (BHC) and other insecticides not included in the study. The samples of cow's milk contained lower concentrations of sufficient total DDT. In a comparison of the means, the samples of human milk showed contamination several times greater than the cow's milk. The pasteurized and powdered milk had lower levels of contamination. The average amount of total DDT in the samples of human milk (0.075 ppm, or micrograms/ml) far exceeded the DDT contamination limit established for milk by FAO/WHO (0.050 ppm). However, there was a wide range in the levels found (the lowest being 0.002, and the highest, 0.680), which means that in some of the samples the concentrations of total DDT were more than 10 times greater than the maximum set by FAO/WHO while in many other cases they were close to the recommended limit.