Toxicity of the insecticide chlorpyrifos to the South American toad Rhinella arenarum at larval developmental stage

Chlorpyrifos (CPF) is an insecticide widely used for pest control in the fruit-productive region of North Patagonia, Argentina, where it is found in superficial waters. The aim of this study was to establish the toxic effects of CPF in Rhinella arenarum toad larvae as a potentially exposed species....

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Detalles Bibliográficos
Autores: Liendro, Natacha, Ferrari, Ana, Mardirosian, Mariana, Lascano, Cecilia Inés, Venturino, Andrés
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2015
País:Argentina
Institución:Universidad Nacional del Comahue
Repositorio:Repositorio Digital Institucional (UNCo)
Idioma:inglés
OAI Identifier:oai:rdi.uncoma.edu.ar:uncomaid/17058
Acceso en línea:http://rdi.uncoma.edu.ar/handle/uncomaid/17058
Access Level:acceso abierto
Palabra clave:Amphibians
Organophosphates
Biomarkers
Cholinesterase inhibition
Oxidative stress
Ciencias de la Tierra y Medio Ambiente
Ciencias Agrarias y Forestales
Descripción
Sumario:Chlorpyrifos (CPF) is an insecticide widely used for pest control in the fruit-productive region of North Patagonia, Argentina, where it is found in superficial waters. The aim of this study was to establish the toxic effects of CPF in Rhinella arenarum toad larvae as a potentially exposed species. We determined the 96 h-LC50 (1.46 ± 0.27 mg/L), the LOEC (0.81 mg/L, LC10) and NOEC (0.43 mg/L, LC1) for CPF lethality as endpoint. We also analyzed biochemical biomarkers in larvae exposed to sublethal CPF concentrations. The IC50 for cholinesterase was 0.113 ± 0.026 mg/L, one order of magnitude lower than the LC50. Carboxylesterase activity was inhibited, buffering OP toxicity on cholinesterase. Reduced glutathione increased after 24 h as an antioxidant response, and decreased at 96 h together with catalase activity, due to oxidative stress. These biochemical effects suggest that environmentally relevant CPF concentrations pose a threat to R. arenarum larvae progression.