Bioconcentration of perfluorinated compounds in blackrock fish, Sebastes schlegeli, at different salinity levels

Bioconcentration of perfluorinated compounds (PFCs) was studied in a biphasic (uptake and elimination) study with blackrock fish, Sebastes schlegeli. The blackrock fish was acclimated to varying salinities over a two-week period before the present study. Among the four selected PFCs: perfluorooctane sulfonate (PFOS), perfluoro-octanoic acid (PFOA), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUnDA), PFUnDA accumulated significantly in serum, followed by PFDA, PFOS, and PFOA, in that order, while the accumulation profile in liver was PFOS > PFUnDA > PFDA > PFOA. Total PFC levels in plasma were approximately four times greater than those found in liver. The uptake and elimination rate constants (K(u) and K(e)) of PFCs decreased as salinity decreased, suggesting delayed diffusion of PFCs between water and fish, possibly associated with the osmolality gradient. A significant correlation was found between bioconcentration factors (BCF) of PFCs and salinity, except for PFOA, possibly resulting from the effects of salinity on biological responses and chemical activity of PFCs. Even though salinity did not affect the kinetics of PFC accumulation in serum and liver, the results provide useful information on the toxicokinetics of PFCs for saltwater fish.