Laboratory Evaluation of Honey Bee Locomotor Abilities: A Method to Identify Sublethal Effects Following Exposure to Pyrethroids and Neonicotinoids

In response to EFSA recommendations for behavioral toxicity assays, this paper details a standardized laboratory protocol to quantify sublethal locomotor effects in honey bees (Apis mellifera). One-day-old workers are anesthetized with CO2 and dosed individually on the dorsal thorax with increasing concentrations of cypermethrin, thiamethoxam or fipronil. The sublethal dose at 48 hours (DSL48h) is identified as the highest exposure not causing mortality and used to evaluate locomotor performance in a 30×30×4 cm vertical open-field arena under controlled illumination. Tracking via video analysis reveals mobility deficits that may compromise foraging or homing behavior. This approach adapts rodent test paradigms to bees and holds promise for interlaboratory validation and regulatory adoption.