[Use of polychlorinated biphenyl congener analysis for monitoring food and raw material of animal origin].

Occurrence of individual polychlorinated biphenyl (PCB) congeners in the environment, foodstuffs and other biological materials was assessed. Analysis of specific PCB congeners (28, 52, 101, 138, 153, 180), occurring in animal raw materials and foodstuffs most frequently, has been implemented. Sample processing, isolation of fat from milk, meat, organs, fat tissue and eggs, and separation of PCB from fats using the sorbents Florisil or Ekosorb (a new Czechoslovak sorbent based on modified silica gel, Kavalier Glassworks, Votice) are described in detail. Individual PCB congeners were determined by capillary gas chromatography (gas chromatograph Varian VISTA 6,000, equipped with a 63Ni ECD; silica capillary column SPB-5, 30 m x 0.32 mm I.D., 0.25 micron film; column temperature programme: 60 degrees C for 2 min, then to 250 degrees C at 20 degrees C/min and held for 13 min; splitless injection). Chromatograms of commercial chemicals Delor 103 and Delor 106 (corresponding to Aroclor 1242 and 1260, respectively), of a mixture of six specific PCB congener standards and of a PCB--containing milk sample are presented in Fig. 1-3. Methods of PCBs estimation, currently used in Czechoslovakia, and benefits of congeneric analysis of PCBs (reproducibility of results, quantification of individual congeners) are discussed. Analysis of specific PCB congeners is used for the assay of PCBs in foodstuffs and investigations of PCBs dynamics in food chains and distribution and accumulation of PCBs in animal organisms. Contents of specific PCB congeners in milk, pork and pig liver and kidney samples are given in Tab. II.(ABSTRACT TRUNCATED AT 250 WORDS)