Pesticide and veterinary drug residues in Belgian beeswax: Occurrence, toxicity, and risk to honey bees

Abstract

Pesticide and veterinary drug residues are one of the stress factors affecting bee health and mortality. To investigate the occurrence, the concentration and the toxicity risk to bees of pesticide residues in four different types of beeswax (brood comb wax, recycled comb wax, honey comb wax, and cappings wax), 182 samples were collected from apiaries located all over the Belgian territories, during spring 2016 and analysed by LC-MS/MS and GC-MS/MS for the presence of 294 chemical residues. The toxicity risk to bees expressed as the Hazard Quotient (HQ) was calculated for each wax sample, according to two scenarios with different tau-fluvalinate LD 50 values. Residues showing the highest prevalence were correlated to bee mortality in a multivariate logistic regression model and a risk-based model was used to predict colony bee mortality. Altogether, 54 different pesticide and veterinary drug residues were found in the four types of beeswax. The residues with a higher likelihood to be retained in beeswax are applied in-hive or with a high lipophilic nature. The multivariate logistic regression model showed a statistically significant influence of chlorfenvinphos on bee mortality. All our results indicated that cappings wax was substantially less contaminated. This national survey on beeswax contamination provides guidelines on the re-use of beeswax by beekeepers and shows the necessity to introduce maximum residue levels

Prioritizing changes in management practices associated with reduced winter honey bee colony losses for US beekeepers

“…The benefits of comb management support previous research that showed that newer comb better support honey bee colony health and reproduction (Berry and Delaplane, 2001). Beeswax has been shown to accumulate pesticide residues (Calatayud-Vernich et al, 2018;El Agrebi et al, 2020a), to levels that could result in increased bee mortality (El Agrebi et al, 2020b). Though colony-level effects (growth and survivorship) from wax contamination had not been confirmed through field trials (Payne et al, 2019), where the authors noted that Varroa levels were a far stronger predictor of colony failure.…”

The use of the Hazard Quotient approach to assess the potential risk to honeybees (Apis mellifera) posed by pesticide residues detected in bee‐relevant matrices is not appropriate

“…links to adverse effects at individual bee‐level or at the colony‐level. The use of the HQ threshold in assessing the risk posed by residues in wax 7,11,13,14,19,20 (or for solitary bees in soil 37 ), where contact transfer factors for compounds are required, 38,39 and in dead bees, 11,14,18,21 without relating to residues following exposure at the LD 50 are not defined, 40 are even more obscure. To compound matters, in assessing the significance of residues in pollen and nectar, the contact LD 50 has also been used, 2,9,13,17 or even an ‘average’ of acute toxicity values, 11,12,18 even though the acute oral LD 50 is clearly more relevant for this exposure route.…”

Organic Beekeeping Practices in Romania: Status and Perspectives towards a Sustainable Development

“…According to Mitchell et al [58], residues of neonicotinoids were detected in a variety of honey samples all over the world. Moreover, application of plant protection products in both urban and rural areas can lead to bee products' contamination [59,60]. Several contaminations by glyphosate were reported in Germany and one organic beekeeper had to destroy a significant amount of honey due to the exceeding the maximum residue levels of glyphosate [61].…”

“…Bee products' contamination may threaten the future of many beekeepers; however, organic beekeeping can bring certain benefits in case of these residues. Furthermore, organic beekeeping can solve the problems with residues from chemical treatments against Varroa, mainly from application of acaricides, which can create residues in bee products [59,63].…”