Assessment of the bioactivity of creosote-contaminated sediment by liver biotransformation system of rainbow trout

A sediment site in the Lake Jamsanvesi (municipality of Petajavesi, Finland ) contaminated by creosote was investigated to assess the possible ecotoxic ological risks it may cause to benthic animals, including ones which may ar ise due to physical measures in remediating the site. It is suggested that polycyclic aromatic hydrocarbons (PAHs) are bioavailable to fish and other aquatic animals during exposure to contaminated water, sediment, and food. In order to assess toxicological risks of sediment contents to fish, juveni le rainbow trout (Onchorhynchus mykiss) were intraperitoneally dosed with e xtracts of the creosote-contaminated sediments and their elutriates. This w as compared to pristine lake sediment spiked with creosote. Activity of CYP 1A1 in trout liver was measured as ethoxyresorufin O-deethylase (EROD). Whe n compared to vechicle controls and the pristine reference sediment (0.9-1. 3 pmol/minlmg PMS protein), the extract of creosote-contaminated sediment o f Lake Jamsanvesi induced EROD activity up 20-30 times with a dose of 100 m g/kg [total PAHs (mg)/(kg) in fish]. The rise of EROD was associated with i ncreasing levels of PAH metabolites in bile, analyzed as 1-OH pyrene equiva lents, (C) 1999 Academic Press.