Article

Comparative Sublethal Toxicity of Nine Pesticides on Olfactory Learning Performances of the Honeybee Apis mellifera

Université Bordeaux 1, Talence, Aquitaine, France
Archives of Environmental Contamination and Toxicology (Impact Factor: 1.9). 03/2005; 48(2):242-50. DOI: 10.1007/s00244-003-0262-7
Source: PubMed

ABSTRACT

Using a conditioned proboscis extension response (PER) assay, honeybees (Apis mellifera L.) can be trained to associate an odor stimulus with a sucrose reward. Previous studies have shown that observations of conditioned PER were of interest for assessing the behavioral effects of pesticides on the honeybee. In the present study, the effects of sublethal concentrations of nine pesticides on learning performances of worker bees subjected to the PER assay were estimated and compared. Pesticides were tested at three concentrations. The highest concentration of each pesticide corresponded to the median lethal dose value (48-h oral LD50), received per bee and per day, divided by 20. Reduced learning performances were observed for bees surviving treatment with fipronil, deltamethrin, endosulfan, and prochloraz. A lack of behavioral effects after treatment with lambda-cyalothrin, cypermethrin, tau-fluvalinate, triazamate, and dimethoate was recorded. No-observed-effect concentrations (NOECs) for the conditioned PER were derived for the studied pesticides. Our study shows that the PER assay can be used for estimating sublethal effects of pesticides on bees. Furthermore, comparisons of sensitivity as well as the estimation of NOECs, useful for regulatory purposes, are possible.

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    • "Neonicotinoids act on the insect nervous system through agonistic actions on nicotinic acetylcholine receptors (Tan et al., 2007). For European honeybees, the LD50 for oral administration of thiamethoxam over 48 h is 5 ng, and LD50 for contact administration over 24 h is 29 ng (Decourtye et al., 2005). Furthermore, the LD50 of thiamethoxam for newly emerged AHBs is 4.28 ng bee À1 (Oliveira et al., 2014). "
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    • ") versus other neonicotinoids, and can act synergistically with N. ceranae to kill honey bees in the laboratory (Vidau et al., 2011; Retschnig et al., 2014a). Taufluvalinate has an acute contact toxicity of 0.2 g μg bee −1 , but was reported to have no lethal effect at daily oral doses of 5 or 10 μg bee −1 (Decourtye et al., 2005). "
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