title: Subchronic organismal toxicity, cytotoxicity, genotoxicity, and feeding response of Pacific oyster (Crassostrea gigas) to lindane (gamma-HCH) exposure under experimental conditions.
abstract: This study evaluated organismal toxicity, cytotoxicity, and genotoxicity and the filtration rate in response to different concentrations of subchronic lindane (gamma-hexachlorocyclohexane [gamma-HCH]), exposure (12 d) in adult Pacific oysters Crassostrea gigas. Oysters were exposed in vivo in laboratory aquaria to 10 different concentrations (0.0-10.0 mg/L) of gamma-HCH. The median lethal concentration (LC50) after 12 d was calculated as 2.22 mg/L. Cytotoxic effects were observed in hemocytes, where the mean cell viability was significantly decreased at 1.0 mg/L of gamma-HCH after 12 d. Genotoxicity of gamma-HCH measured by single cell gel electrophoresis assay, in hemocytes was evident at 0.7 mg/L of gamma-HCH after 12 d. After 4 h of exposure to gamma-HCH, filtration rates were reduced compared with controls to 65.8 and 38.2% at concentrations of 0.3 and 0.7 mg/L, respectively, and after 11 d of exposure, filtration rates were reduced to 60.4 and 30.9% at concentrations of 0.1 mg/L and higher. These results show the subchronic effects of gamma-HCH at different concentrations and effect sensitivities are categorized as filtration rate < genotoxicity < cytotoxicity < mortality. The relevance of integral toxicity evaluation, considering different endpoints from molecular, cellular, and individual levels is discussed.
authors.affiliation: Department of Environmental Management and Conservation, Toxicogenomic and Reproduction of Aquatic Organism Laboratory (CIBNOR), P.O. 128, La Paz, Baja California Sur, México.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Anguiano
authors.forename: Raul
authors.initials: R
authors.lastname: Llera-Herrera
authors.forename: Emilio
authors.initials: E
authors.lastname: Rojas
authors.forename: Celia
authors.initials: C
authors.lastname: Vazquez-Boucard
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D020552:Comet Assay; D005247:Feeding Behavior / Q000187:drug effects*; D001556:Hexachlorocyclohexane / Q000633:toxicity*; D007306:Insecticides / Q000633:toxicity*; D009152:Mutagenicity Tests; D010125:Ostreidae; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D007306:Insecticides; D014874:Water Pollutants, Chemical; D001556:Hexachlorocyclohexane