BEEware: overcoming risks to bees posed by agrochemical synergies through transcriptomics

Increasing evidence has linked agrochemical exposure to significant declines in pollinator populations, prompting heightened concerns and legislative actions. However, recent studies demonstrate that even legally-applied pesticides continue to adversely affect social bees. A critical challenge in addressing this issue is the co-exposure of pollinators to multiple agrochemicals. In agricultural environments, pollinators are typically exposed to complex mixtures of agrochemicals, rather than the single products upon which risk assessment has been based. This is a problem because recent work has highlighted that agrochemicals often interact synergistically, such that their combined effects are significantly greater than anticipated, and that such synergistic interactions are both larger and more common than expected. Finding a means to identify synergy during the licensing process is difficult because synergistic interactions are hard to predict based on biochemical properties, and because the number of potential mixtures that may be encountered in the real world is too large to allow for untargeted testing of mixtures. I propose a means to overcome this barrier, through transcriptomic profiling of exposure to single products to detect key indicators of synergy for social bees. Gene expression can detect key overriding impacts of individual agrochemicals on bee physiology, and comparison of profiles could potentially predict synergistic partners. Building upon my background in insect transcriptomics and the expertise in agrochemical stress within my proposed research group, I will combine large-scale transcriptomic resources with a comprehensive pre-existing database of synergistic agrochemical pairs to explore the key general shared features of synergistic pairs, such as shared metabolic targets. In doing so, I will identify potential biomarker genes to provide a more sensitive, short-term experimental method for bioassays in pesticide environmental risk assessment.