ANALYSIS OF TRACES OF ORGANO-CHLORIDE PES TICIDES AND OF POLYCHLORO-BIPHENYLS IN FOODS OF ANIMAL ORIGIN - MULTIRESIDUE RAPID METHOD - STUDYOF THE REPEATABILITY AND IMPROVEMENT OF PURIFICATION

A rapid method of extraction and purification of pesticide traces in f oods of animal origin with high content of fat is described. The speci ficity of this method consists in the extraction step which is perform ed at a temperature at a temperature of -10 degrees C. Resolution of a ll components has been achieved thanks to the use of a purification pr ocedure of fractionation to separate pesticides adn PCBs. Detection li mits are between 1.6 and 3.1 ppb and the interval of confidence of the purification yield on Florisil is from 70 to 103%. Interlaboratory tr ials led to the calculation of relative repeatability adn reproducibil ity values, evaluated to be 10 and 30%, respectively. These values hav e been observed over a long period (several years) and guarantee the r obustness of the method. Analytical parameters obtained with the metho d comply with the application of European Regulations regarding the de tection of pesticide residues in food of animal origin.