Comparative lipidomic and proteomic analysis reveals species-specific differences in midgut composition and...

The importance of bee pollinators for agricultural and ecological reasons is widely recognised and the declines in pollinator populations have been partly attributed to insecticide exposure in addition to habitat loss, climate change, pathogens and parasites. While metabolic detoxification of insecticides in bees is well-studied, less is known about species-specific differences in absorption. This study investigates the link between midgut composition and patterns of absorption in two key pollinator species, the Western honeybee Apis mellifera and the buff-tailed bumblebee Bombus terrestris.

Comprehensive lipidomic and proteomic analysis revealed large-scale differences in the gut composition between the two species, with B. terrestris showing a higher ratio of sphingomyelins to phosphatidylcholines compared to A. mellifera. Ex vivo Ussing chamber experiments and in vivo feeding assays demonstrated that the A. mellifera displayed higher midgut permeability for the two insecticides imidacloprid and chlorantraniliprole when compared to B. terrestris. The observed structural variation in midgut composition correlates with the differing absorption rates, suggesting a potential mechanism for species-specific variations in insecticide toxicity.

The finding that A. mellifera midguts display a higher rate of insecticidal absorption provides a novel insight into the role of absorption in bee toxicology. This also has implications for the development of more selective insecticides and improved risk assessment strategies for non-target organisms. © 2025 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.