Dietary exposure of finfish to aromatic contaminants and tissue distribution

Large rainbow trout (400 g) were exposed to food pellets spiked with four polycyclic aromatic compounds (PACs). Muscle, liver, internal organs, fatty tissue, and blood were analyzed after 5, 10, 15, and 19 weeks for PAC, lipid, and moisture content. At all collection times, concentrations expressed on a per gram basis were higher in fatty tissue and internal organs, followed by liver and muscle, and lowest levels were observed in blood. When examining the tissue burden, the highest bioaccumulations of carbazole, dibenzofuran, dibenzothiophene, and fluorene were in muscle and internal organs, intermediate in fatty tissue, and lowest in blood and liver. Carbazole with the lowest log K(OW) showed the lowest concentration within any tissue. Levels in tissues were significantly correlated to log K(OW) (> 5% level of significance), especially with longer exposure, and were more highly correlated when examining muscle, fatty tissue, and internal organs (> 0.05%). Different tissues displayed different time trends, and ratios between organs help determine the length of exposure. The most striking change in levels observed with time was in internal organs relative to other tissues, particularly when compared to daily exposure. The elimination of contaminants in feces and gallbladder bile was also compared, because they represent additional tools to assess recent exposure.