title: Sublethal effects induced by morphine to the freshwater biological model Dreissena polymorpha.
abstract: Opioids are considered as emerging contaminants in aquatic ecosystems, mainly due to their large illicit consume worldwide. Morphine (MOR) is the main opiate and it was commonly found at measurable concentrations in freshwaters. Even though its occurrence is well documented, just limited information is available regarding its hazard to nontarget organisms. The aim of this study was of the evaluation of sublethal effects induced by MOR to the freshwater bivalve Dreissena polymorpha. We exposed mussels to two MOR concentrations (0.05 µg/L and 0.5 µg/L) for 14 days and we investigated the sublethal effects by a suite of biomarkers. The Neutral Red Retention Assay (NRRA) was used as a test of cytotoxicity, while the oxidative stress was evaluated by the activity of antioxidant and detoxifying enzymes, namely catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione-S-transferase (GST), and by measuring the levels of lipid peroxidation (LPO) and protein carbonylation (PCC). The genetic damage was assessed by the Single Cell Gel Electrophoresis (SCGE) assay, the DNA diffusion assay and the micronucleus test (MN test). Finally, the filtration rate of D. polymorpha was evaluated in order to investigate possible physiological effects. Both tested concentrations reduced the lysosome membrane stability of bivalves, but only the highest MOR concentration induced significant changes in the activity of antioxidant enzymes (SOD, CAT, and GPx) and increase in lipid peroxidation levels. Slight increase in primary DNA fragmentation was noticed, while no fixed genetic damage and alterations of the filtering rate were found.
authors.affiliation: Department of Biosciences, University of Milan, Via Celoria 26, 20133, Milan, Italy.
authors.forename: Stefano
authors.initials: S
authors.lastname: Magni
authors.affiliation: Department of Biosciences, University of Milan, Via Celoria 26, 20133, Milan, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Parolini
authors.affiliation: Department of Biosciences, University of Milan, Via Celoria 26, 20133, Milan, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Binelli
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D002374:Catalase / Q000378:metabolism; D020552:Comet Assay; D053938:DNA Fragmentation / Q000187:drug effects; D049875:Dreissena / Q000187:drug effects* / Q000201:enzymology / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008954:Models, Biological; D009020:Morphine / Q000633:toxicity*; D009499:Neutral Red / Q000737:chemistry; D018384:Oxidative Stress / Q000187:drug effects; D050050:Protein Carbonylation / Q000187:drug effects; D013482:Superoxide Dismutase / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D014874:Water Pollutants, Chemical; D009499:Neutral Red; D009020:Morphine; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D005982:Glutathione Transferase
keywords: Dreissena polymorpha; biomarkers; morphine