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Exposure of larvae to thiamethoxam affects the survival and physiology of the honey bee at post-embryonic stages
2017
Tavares, Daiana Antonia | Dussaubat, Claudia | Kretzschmar, Andre | Carvalho, Stephan Malfitano | Silva-Zacarin, Elaine C.M. | Malaspina, Osmar | Bérail, Géraldine | Brunet, Jean-Luc | Belzunces, Luc | Departamento de Biologia ; Universidade Estadual Paulista Júlio de Mesquita Filho = São Paulo State University (UNESP) | Abeilles et Environnement (AE) ; Institut National de la Recherche Agronomique (INRA)-Avignon Université (AU) | Biostatistique et Processus Spatiaux (BioSP) ; Institut National de la Recherche Agronomique (INRA) | Universidade Federal de Lavras = Federal University of Lavras (UFLA) | Universidade Federal de São Carlos [São Carlos] (UFSCar) | Laboratoire de l'Environnement et de l'Alimentation de la Vendée ; Institut National de la Recherche Agronomique (INRA) | Sao Paulo Research Foundation 2013/21634-8 2012/50197-2
Under laboratory conditions, the effects of thiamethoxam were investigated in larvae, pupae and emerging honey bees after exposure at larval stages with different concentrations in the food (0.00001 ng/µL, 0.001 ng/µL and 1.44 ng/µL). Thiamethoxam reduced the survival of larvae and pupae and consequently decreased the percentage of emerging honey bees. Thiamethoxam induced important physiological disturbances. It increased acetylcholinesterase (AChE) activity at all developmental stages and increased glutathione-S-transferase (GST) and carboxylesterase para (CaEp) activities at the pupal stages. For midgut alkaline phosphatase (ALP), no activity was detected in pupae stages, and no effect was observed in larvae and emerging bees. We assume that the effects of thiamethoxam on the survival, emergence and physiology of honey bees may affect the development of the colony. These results showed that attention should be paid to the exposure to pesticides during the developmental stages ofthe honey bee. This study represents the first investigation of the effects of thiamethoxam on the development of A. mellifera following larval exposure.
Показать больше [+] Меньше [-]B-type esterases in the snail <em>Xeropicta derbentina</em>: an enzymological analysis to evaluate their use as biomarkers of pesticide exposure
2009
Laguerre, Christel | Sanchez-Hernandez, Juan C. | Köhler, Heinz-R. | Triebskorn, Rita | Capowiez, Yvan | Rault, Magali | Mazzia, Christophe | Abeilles et Environnement (AE) ; Institut National de la Recherche Agronomique (INRA)-Avignon Université (AU) | Santé Végétale (SV) ; Institut National de la Recherche Agronomique (INRA)-École Nationale d'Ingénieurs des Travaux Agricoles - Bordeaux (ENITAB) | Universidad de Castilla-La Mancha = University of Castilla-La Mancha (UCLM) | Eberhard Karls Universität Tübingen = Eberhard Karls University of Tuebingen | Steinbeis Transfer-Center for Ecotoxicology and Ecophysiology | Unité de recherche Plantes et Systèmes de Culture Horticoles (PSH) ; Institut National de la Recherche Agronomique (INRA)
International audience | The study was prompted to characterize the B-type esterase activities in the terrestrial snail <em>Xeropicta derbentina</em> and to evaluate its sensitivity to organophosphorus and carbamate pesticides. Specific cholinesterase and carboxylesterase activities were mainly obtained with acetylthiocholine (Km =77.2 mM; Vmax= 38.2 mU/mg protein) and 1-naphthyl acetate (Km= 222 mM, Vmax= 1095 mU/mg protein) substrates, respectively. Acetylcholinesterase activity was concentration-dependently inhibited by chlorpyrifos-oxon, dichlorvos, carbaryl and carbofuran (IC50 =1.35 x 105–3.80 x 108 M). The organophosphate-inhibited acetylcholinesterase activity was reactivated in the presence of pyridine-2- aldoxime methochloride. Carboxylesterase activity was inhibited by organophosphorus insecticides (IC50 =1.20 x 105–2.98 x 108 M) but not by carbamates. B-esterase-specific differences in the inhibition by organophosphates and carbamates are discussed with respect to the buffering capacity of the carboxylesterase to reduce pesticide toxicity. These results suggest that B-type esterases in<em> X. derbentina</em> are suitable biomarkers of pesticide exposure and that this snail could be used as sentinel species in field monitoring of Mediterranean climate regions
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