Effects of chronic dietary thiamethoxam and prothioconazole exposure on Apis mellifera worker adults and brood.

Background: Chronic exposure of honey bees (Apis mellifera Linnaeus) to the neonicotinoid thiamethoxam and the fungicide prothioconazole is common during foraging in agricultural landscapes. We evaluated the survival and hypopharyngeal gland development of adult worker honey bees, and the survival of the worker brood when chronically exposed to thiamethoxam or thiamethoxam and prothioconazole in combination.

Results: We found that 30 days of exposure to 40 μg kg of thiamethoxam significantly (P < 0.