Toxicity of mercury and post-exposure recovery in Corbicula fluminea: Neurotoxicity, oxidative stress and oxygen consumption

摘要: Abstract The toxicity of mercury to the invasive species Corbicula fluminea and post-exposure recovery were investigated in relation previous developmental exposure distinct environmental conditions. Bivalves collected estuaries Minho River (M-est) Lima (L-est) that have several abiotic differences, including contamination, with former being generally less contaminated. After 14 days acclimation laboratory conditions, two 14-day bioassays performed simultaneously: one bivalves from M-est other L-est. In each bioassay, treatments were: dechlorinated tap water (clean medium) for 8 days, clean medium 14 days, 31 µg/L 8 days followed by 6 days (post-exposure recovery). effect criteria oxygen consumption rate (OCR), activity enzymes cholinesterases (ChE), NADP-dependent isocitrate dehydrogenase (IDH), octopine (ODH), catalase (CAT), glutathione reductase (GR), peroxidase (GPx) S-transferases (GST) lipid peroxidation (LPO) levels. Exposure caused significant (p ≤ 0.05) inhibition GR bivalves, whereas no adverse effects observed L-est animals. Moreover, evidences delayed 8-day OCR, IDH LPO levels found individuals but not those depression OCR animals both estuaries, indicating reduced individual fitness hypoxia oxidative stress damage exposed Differences conditions which wild likely contributed differences sensitivity between bivalves. results this study highlight importance investigating toxicity, recovery, taking into consideration background contamination original habitats when assessing contaminants on populations.