Evaluation of enzymatic biomarkers and lipoperoxidation level in Hediste diversicolor exposed to copper and benzo[a]pyrene.

This study aims to evaluate the effects of exposure to copper, benzo[a]pyrene, and to their mixture on enzymatic and lipid peroxidation biomarkers in Hediste diversicolor. Worms were submitted to 1 microM of both single compounds and to their mixture during a period of test of 12, 24, 36, and 48 h. The biomarkers selected in this work were the activities of cytochrome P450-dependent NADPH cytochrome c reductase (NADPH red) as phase I enzyme, glutathione-S-transferase (GST) as phase II enzyme, and the acetylcholinesterase (AChE) activity as neurotoxicity marker. Oxidative stress was evaluated using catalase activity (CAT) and malondialdehyde accumulation (MDA). The NADPH red activity was not significantly affected by copper exposure; it shows a drastic increase in both B[a]P and mixture-exposed organisms. GST activities were significant in B[a]P-exposed worms only after 36 h, and in animals exposed to the mixture after 12 and 48 h. The ACHE activity was inhibited only in B[a]P-exposed worms.