APIStrip, a new tool for environmental contaminant sampling through honeybee colonies.

Honeybee colonies are proven bio-samplers in their foraging area, as organic contaminants such as pesticides are continuously deposited in their hives. However, the use of honeybee colonies for the biomonitoring of contaminants requires the sampling of biological matrices such as bees, pollen, honey or beeswax. This active sampling alters the colonies, especially in the case of frequent sampling intervals. In this study, a non-biological passive sampler based on Tenax TA is described: the APIStrip (Adsorb Pesticide In-hive Strip). A concentrated solution of Tenax in dichloromethane has been applied to a polystyrene strip, resulting in a bee-proof, in-hive passive sampler. The pesticides and related contaminants adsorbed onto its surface can be extracted in acetonitrile and analyzed by LC-MS/MS and GC-MS/MS. The APIStrip preparation has been optimized, the optimal exposure period has been stablished as 14 days and the stability of the pesticides on the APIStrip surface has been evaluated. Preliminary tests demonstrated the efficacy, sensitivity, representativeness and reproducibility of the APIStrip-based sampling when compared to the analysis of beeswax comb, which facilitates the detection of contaminants even in beehives exposed to low polluting pressure. Field studies in Denmark, performed in the INSIGNIA monitoring study over a six-month period, demonstrated their value and applicability by detecting 40 different pesticide residues.