MULTIVARIATE MODELING OF PCB BIOACCUMULATION IN 3-SPINED STICKLEBACK (GASTEROSTEUS-ACULEATUS)

Three-spined sticklebacks were exposed to 20 polychlorinated biphenyls (PCBs) through gastrointestinal intake. The PCBs, viz. 2,2',3,4- TeCB , 2,2',4,6'-TeCB, 2,3,3',5'-TeCB, 2,3,4,4'-TeCB, 2,3',4,5'-TeCB, 3,3', 4,5-TeCB, 2,2',3,4',6-PeCB, 2,2',4,4',5-PeCB, 2,2',4,6,6'-PeCB, 2,3,3' ,5,6-PeCB, 2,3,4,4',6-PeCB, 3,3'4,4',5-PeCB, 2,2',3,4,5,6'-HxCB, 2,2', 4,4',5,5'-HxCB, 3,3',4,4',5,5'-HxCB, 2,2',3,3',4,5,6-HpCB, 2,2',3,4,4' ,6,6'-HpCB, 2,2',3,4',5,6,6'-HpCB, 2,3,3',4,4',5,6-HpCB, and 2,3,3',4' ,5,5',6-HpCB, were selected by means of a full factorial design in com bination with principal component analyses based on several physicoche mical properties of tetra- through hepta-PCBs. After exposure to the t raining set, pooled samples of the sticklebacks were analyzed by GCMS after lipid determination and cleanup using Florisil open-column chrom atography. Bioaccumulation factors (BAFs) were calculated on a lipid b asis by dividing the PCB concentrations in the fish by the respective concentrations in the feed. Higher chlorinated PCBs showed, in general , higher bioaccumulation than the lower chlorinated congeners. Polychl orinated biphenyls with vicinal hydrogens in the meta- and para-positi ons exhibited low bioaccumulation. Finally 18 of the 20 measured BAFs were used to calculate a multivariate quantitative structure-activity relationship (QSAR) by means of partial least squares fitting to laten t structures. By applying this QSAR, the bioaccumulation potentials of 136 nontested tetra- through hepta PCB congeners were predicted.