Coumaphos Distribution in the Hive Ecosystem: Case Study for Modeling Applications

Abstract

Pesticides are currently used inside hives, against the honeybee parasite Varroa destructor, producing unwanted contamination effects. To assess the distribution and fate of one of these pesticides (coumaphos), two experimental hives were treated with Perizin (the commercial product containing the active ingredient coumaphos). Samples of honey, wax, pollen, adult bees and larvae taken before treatment and up to 104 days afterwards, showed diffuse contamination. Wood hedges and wax bridges, where the pesticide solution was applied, were analysed as well. A mass balance was calculated, yielding a recovered amount of around 60% just after treatment and 38% 1 month later. Directly contaminated surfaces and wax contained the highest amount of residues. Wax and honey contained different amounts (10, and 0.1% respectively) but both retained residues for long time. Bees ingest most of the product just after treatment, then rapidly eliminate it by metabolism, advection and deposition processes. On the basis of analytical results, a simple model (level I of the fugacity model) was applied to the hive system for different pesticides (coumaphos, malathion, fluvalinate and bromopropylate). Predicted concentrations in wax and honey were compared with those measured, indicating the good predictive capability of this approach.

Interaction between pesticides and other factors in effects on bees

“…menthol, thymol. (Tremolada et al, 2004) assessed the possible distribution of coumaphos applied as Perizin within a beehive following a varroacide treatment with 32mg/hive. Based on the vapour pressure of 0.013 mPa at 20C this equates to an air saturation of 1.9 μg/m3 and the volume of air within a hive of 0.2m3 gives a saturation in the air of 0.000001%.…”

“…The majority of published studies relate to in-hive treatments with varroacides and antibiotics and solely measured residues in honey intended for human consumption (e.g. (deGrandi-Hoffman and Hagler, 2000;Nakajima et al, 1997;Nakajima et al, 1998;Bonzini et al, 2011;Tremolada et al, 2004;Tremolada et al, 2011). However, there are a small number of studies which specifically address the distribution of incoming contaminated nectar within hives including Nixon and Ribbands (1952), who demonstrated that releasing just six foragers fed with radiolabelled sμgar into a colony resulted in about 20% of the workers in the brood area receiving some labelled food within 3.5 hours and this included nurse bees which demonstrated the potential exposure of brood.…”

“…Only fluvalinate was detected at significant levels in bee heads and in larvae suggesting high levels of trophyllaxis occur within the hive. Tremolada et al (2004) followed the distribution of the varroacide coumaphos in 2 hives. Although deliberately introduced into the hive as a varroacide, unlike other varroacides such as fluvalinate which is formulated in a plastic strip, the formulation was applied in water to the top bars of the frames as a liquid and can thus provide some information on the distribution around the hive if the "indirectly contaminated" compartments are considered.…”

Research strategies to improve honeybee health in Europe

“…It is also used widely to control the mites in beekeeping, and accumulates in the wax of the comb at high concentrations (Bogdanov et al, 1998;Wallner, 1999;Tremolada et al, 2004). It is one of the most common pesticides found in honeybee colonies.…”

Acute Contact Toxicity Test of Oxalic Acid on Honeybees in the Southwestern Zone of Uruguay

“…Currently, the main biological factor harming honey production in Uruguay is the prevalence of varroosis (the infection of hives caused by the mite Varroa destructor) . However, efforts to control mites with synthetic miticides (normally with xenobiotic characteristics) have led to two additional problems, that is, an increase in the risk of selecting resistant V. destructor strains (Lodesani et al, 1995;Elzen et al, 2000;Thompson et al, 2002;Pettis, 2004) and an increase in the risk of hive products by miticides (e.g., coumaphos) (Wallner, 1999;Tremolada et al, 2004). More specifically, the first problem has led to a progressive decrease in the efficacy of synthetic acaricides to control resistant V. destructor strains.…”