Presence and distribution of pesticides in apicultural products: A critical appraisal

Pesticide analysis in bee-related matrices is a well-established methodology mainly based on LC-MS/MS and GC-MS/MS instrumentation that allows the determination of the chemical origin of certain colony disorders, as well as the assessment of the environmental contamination and the safety of apicultural products of human interest. The present work approaches this issue from two different perspectives. The first one is the critical evaluation of 50 representative monitoring studies performed in different world regions over the 2011–2021 period. These studies determined the pesticides in honey bee colonies by the analysis of pollen, honey, beeswax, bee bread and honey bees –healthy or poisoned–. The second approach revises the current legislations regarding the presence of chemicals in apicultural matrices, mainly honey, and the need of enlarging their application to other apicultural goods and broader scopes of target pesticides. For their part, the monitoring surveys revealed the need of establishing a straightforward definition of each apicultural matrix to avoid misleading results. The data presented showed some of the most widespread agricultural pesticides worldwide: chlorpyrifos, imidacloprid, dimethoate and tebuconazole. Out of the 363 pesticide residues detected by the abovementioned studies, these were reported by in more than half, distributed in the apicultural matrices according to their physicochemical properties. Some widely employed herbicides with specific difficulties in their analysis, like glyphosate, received scarce attention, but new reports show its occurrence in honey. Some ubiquitous varroacides ‒coumaphos, tau-fluvalinate, amitraz‒ are being slowly replaced by more “green” substances such as thymol or oxalic acid. The analytical methodologies should therefore evolve to include these and other new chemicals employed in agriculture and apiculture.