Enzymatic biomarkers as tools to assess environmental quality: A study of exposure of the honeybee Apis mellifera to insecticides

Universidade Federal de Lavras, Departamento de Entomologia, Lavras, Minas Gerais, Brazil.
Environmental Toxicology and Chemistry (Impact Factor: 3.23). 09/2013; 32(9). DOI: 10.1002/etc.2288
Source: PubMed


This work was intended to evaluate the responses of enzymes in the honey bee Apis mellifera upon exposure to deltamethrin, fipronil and spinosad and their use as biomarkers. After LD50 determination, honey bees were exposed at doses of 5.07 and 2.53 ng/bee for deltamethrin, 0.58 and 0.29 ng/bee for fipronil and 4.71 and 2.36 ng/bee for spinosad (equivalent to LD50 /10 and LD50 /20, respectively). The responses of acetylcholinesterase (AChE), carboxylesterases (CaEs1-3), glutathione-S-transferase (GST), catalase (CAT) and alkaline phosphatase (ALP) were assessed. The results showed that deltamethrin, fipronil and spinosad modulated these biomarkers differentially. For the enzyme involved in the defense against oxidative stress, fipronil and spinosad induced CAT activity. For the remaining enzymes, three response profiles were identified: (i) Exposure to deltamethrin induced slight effects and modulated only CaE-1 and CaE-2 with opposite effects. (ii) Spinosad exhibited an induction profile for most of the biomarkers except AChE. (iii) Fipronil did not modulate AChE, CaE-2 or GST, increased CAT and CaE-1, and decreased ALP. Thus, this set of honey bee biomarkers appears to be a promising tool to evaluate environmental and honey bee health, and it could generate fingerprints to characterize exposures to pesticides. Environ Toxicol Chem © 2013 SETAC.

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Available from: Stephan Malfitano Carvalho, Nov 12, 2014
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