Bioaccumulation of dehydroabietic acid in rainbow trout (Oncorhynchus mykiss): role of biotransformation enzymes

The role of Phase I and Phase II metabolism in rainbow trout on the bioaccumulation of dehydroabietic acid, an abundant and persistent compound found in pulp and paper mill effluents, was investigated using known inducer/inhibitor compounds for cytochromes P450 (P450s), ethoxyresorufin O-deethylase (EROD) and uridine diphosphoglucuronosyltransferase (UDPGT). The inducer/inhibitor compounds consisted of piperonyl butoxide (PBO), salicylamide (SAL) and β-naphthoflavone (βNF). PBO induced EROD, SAL had no effect on the measured biotransformation enzyme activities and βNF induced EROD and UDPGT. Treatment of trout with these compounds altered the bioaccumulation and distribution of dehydroabietic acid (DHAA) between bile, liver, and muscle in trout exposed to both the pure compound and an untreated mill effluent indicating that biotransformation enzyme activities may directly influence these bioconcentration processes in recipient biota.