Enhancing the environmental monitoring of pesticide residues through Apis mellifera colonies: Honey bees versus passive sampling

Evaluation of the honeybee exposome in European apiaries by combining passive samplers and liquid chromatography with Zeno trap-time-of-flight mass spectrometry

This study introduces an analytical methodology that combines passive sampling with ultra-high pressure liquid chromatography coupled with a high-end quadrupole-time-of-flight mass spectrometer (UHPLC-QTOF-MS) for monitoring the honeybee (Apis mellifera L.) exposome across various European regions and seasons. The sampling methodology employs the recently developed adsorb pesticide in-hive strips (APIStrip) passive samplers, which use TENAX® TA adsorbent, to collect a wide range of chemicals when placed inside beehives. Following acetonitrile-based desorption, extracts were analyzed by UHPLC-QTOF-MS, equipped with an advanced ion trap -the Zeno trap- that enhances tandem-mass spectrometry (MS/MS) signals and improves mass accuracy, facilitating efficient feature annotation. A non-targeted analysis (NTA) approach, combined with multivariate analysis, was used to simultaneously identify exposure analytes (e.g.natural products) and effect-related metabolites associated with honeybee health and condition (e.g. pheromones and other compounds emitted by bees). This methodology revealed geographical and seasonal variations in the chemical profiles of honeybee hives. In the evaluated Nordic countries, natural products from plants and pollen, along with bee-emitted substances such us neurotransmitters and pheromones, were prevalent. Seasonal analysis in Denmark revealed distinct chemical profiles associated with blooming flowers and peak brood rearing activity in April. This integrated, non-invasive methodology has proven highly effective in assessing the honeybee exposome, providing valuable insights into how environmental factors influence the chemical profiles emitted by bees.

Environmental assessment of PAHs through honey bee colonies - A matrix selection study

The steady conditions of temperature, humidity and air flux within beehives make them a valuable location for conducting environmental monitoring of pollutants such as PAHs. In this context, the selection of an appropriate apicultural matrix plays a key role in these monitoring studies, as it maximizes the information that will be obtained in the analyses while minimizing the inaccurate results. In the present study, three apicultural matrices (honey bees, pollen and propolis) and two passive samplers (APIStrips and silicone wristbands) are compared in terms of the number and total load of PAHs detected in them. Samplings took place in a total of 11 apiaries scattered in Austria, Denmark, and Greece, with analyses performed by GC-MS/MS. Up to 14 different PAHs were identified in silicone wristbands and pollen, whereas the remaining matrices contained a maximum of five contaminants. Naphthalene, 1-methylnaphthalene, 2-methylnaphthalene, and pyrene were found to be the most prevalent substances in the environment. Recovery studies were also performed; these suggested that the chemical structure of APIStrips is likely to produce very strong interactions with PAHs, thus hindering the adequate desorption of these substances from their surface. Overall, silicone wristbands placed inside the beehives proved the most suitable matrix for PAH monitoring through honey bee colonies.

Comparison of APIStrip passive sampling with conventional sample techniques for the control of acaricide residues in honey bee hives

Western honey bees are very sensitive bioindicators for studying environmental conditions, hence frequently included in many investigations. However, it is very common in both research studies and health surveillance programs to sample different components of the colony, including adult bees, brood and their food reserves. These practices are undoubtedly aggressive for the colony as a whole, and may affect its normal functioning and even compromise its viability. APIStrip-based passive sampling allows long-term monitoring of residues without affecting the colony in any way. In this study, we compared the effectiveness in the control of acaricide residues by using passive and conventional sampling, where the residue levels of the acaricides coumaphos, tau-fluvalinate and amitraz were evaluated. Conventional and APIStrip-based sampling differ in methods for evaluating bee exposure to residues. APIStrip is less invasive than conventional sampling, offers more efficient measurement of environmental contaminants, and can be stored at room temperature, saving costs and minimizing operator error.