ABSTRACT This article reviews the recent analytical methods used for the analysis of pesticides in bee health surveys which include bees, beebread, beeswax, honey, nectar and pollen. Limits of detection (LOD) and limits of quantitation (LOQ) for pesticide residue methods need to be <1/10 the acute toxicity (LD50) for bees which is more challenging for insecticide analysis. LD50’s are expressed in units of micrograms/bee where mass of a bee is ~0.1 g. The most frequent multi-residue analysis method used was liquid chromatography-tandem mass spectrometry for pesticide classes including carbamates, conazole fungicides, neonicotinoid insecticides, and strobilurin fungicides. For improved LODs for organochlorines and pyrethroids, GC-MS or GC-MS/MS analysis was also required. Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) was predominately used in recent studies of pesticides in pollen, beebread, and bees which can be attributed to the ease and cost benefit of this approach with considerations of modifications of the method to account for removal of fats and phenolic compounds either in the extraction step or in the clean-up step requiring appropriate selection of the dispersive solid phase extraction (dSPE) sorbent used during clean-up. Sample preparation approaches were more varied for the analysis of pesticides in honey and beeswax and also included solid phase extraction (SPE), liquid-liquid extractions, and specialized miniaturized approaches. LODs varied for many individual target analytes over an order of magnitude which is attributed to the extraction and clean-up approach and chromatographic-mass spectrometry operating conditions. Future method development for pesticide residue analysis should consider further reductions in sample size requirements and combining sample preparation approaches to minimize interferences. Separation conditions in ultrahigh performance liquid-chromatography (UPLC) or nano-LC should be optimized to improve detection limits and further minimize impacts of interferences. This would allow for analysis of environmentally relevant concentrations of pesticides from individual beehives, thereby reducing the need to pool samples to obtain sufficient extract for a more complete analysis of a full range of pesticides in usage.
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