title: Total oxyradical scavenging capacity and cell membrane stability of haemocytes of the Arctic scallop, Chlamys islandicus, following benzo(a)pyrene exposure.
abstract: Industrial activities, notably oil and gas industries, are expanding in the Arctic. Most of the biomarkers were developed using temperate organisms living at temperatures above 10 degrees C. Little is known about the biomarker responses of organisms living between -1.88 and 5 degrees C. Therefore, assessment of the toxicity of chemicals to cold-water adapted species is required. In this study, the Arctic scallop, Chlamys islandicus, was selected as a key species for bio-monitoring because of wide distribution in Arctic waters and its commercial value. Test animals, stored in seawater at 2 degrees C, were injected with benzo(a)pyrene (diluted in cod liver oil 5 mg ml(-1)) in the adductor muscle every 24 h for four days giving a final dose of 0, 74 and 90.6 mg kg(-1) wet weight for control, low and high dose, respectively. The biomarkers used were total oxyradical scavenging capacity (TOSC) in the digestive gland and cell membrane stability of haemocytes. TOSC values were significantly reduced (ca. 30%) in exposed groups (P < 0.05), indicating a depletion in oxyradical molecular scavengers. The antioxidant defences appeared to be overwhelmed by the reactive oxygen species as the plasma membranes of haemocytes were destabilised (P < 0.05) probably due to lipid peroxidation. These data indicate that reactive oxygen species (ROS) were produced by Arctic scallops via the metabolisation of benzo(a)pyrene at 2 degrees C.
authors.affiliation: Plymouth Environmental Research Centre, Department of Biological Sciences, University of Plymouth, Devon, UK. lionel.camus@rf.no
authors.forename: L
authors.initials: L
authors.lastname: Camus
authors.forename: M B
authors.initials: MB
authors.lastname: Jones
authors.forename: J F
authors.initials: JF
authors.lastname: Børseth
authors.forename: B E
authors.initials: BE
authors.lastname: Grøsvik
authors.forename: F
authors.initials: F
authors.lastname: Regoli
authors.forename: M H
authors.initials: MH
authors.lastname: Depledge
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D000975:Antioxidants / Q000032:analysis; D001110:Arctic Regions; D001564:Benzo(a)pyrene / Q000009:adverse effects* / Q000378:metabolism; D015415:Biomarkers / Q000032:analysis; D002462:Cell Membrane / Q000473:pathology*; D003080:Cold Temperature; D016166:Free Radical Scavengers / Q000032:analysis*; D006434:Hemocytes / Q000502:physiology; D008974:Mollusca / Q000502:physiology*; D018384:Oxidative Stress; D014874:Water Pollutants, Chemical / Q000009:adverse effects* / Q000378:metabolism
chemical_list: D000975:Antioxidants; D015415:Biomarkers; D016166:Free Radical Scavengers; D014874:Water Pollutants, Chemical; D001564:Benzo(a)pyrene