This European Standard specifies a gas chromatographic/mass spectrometric method for the determination of organochlorine pesticides (OC""s) and polychlorinated biphenyls (PCBs) in animal feeding stuffs and oil.The method is applicable to animal feeding stuffs with a water content up to about 20 wt% and oil/fatty samples containing residues of one or more of the following OC""s and PCBs and some of their isomers and degradation products: - Aldrin;- Dieldrin;- Chlordane (= sum of Chlordane isomers and Oxychlordane);- DDT (= sum of isomers op'-DDT, pp'-DDT, pp'-TDE (pp'-DDD), and pp'-DDE);- Endosulfan (sum of µ¡-/µ¢-isomers and Endosulphanesulphate);- Endrin;