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–1 of thiamethoxam significantly (P 0.05) between controls and adult workers exposed to thiamethoxam and/or prothioconazole. CONCLUSION These results indicate that chronic exposure to field‐realistic doses of thiamethoxam and/or prothioconazole are unlikely to affect the survival of adult workers and brood. © 2019 Society of Chemical Industry Honey bees are chronically exposed to pesticides in honey and pollen. We investigated the effects of neonicotinoids and fungicides on survival on honey bee worker adults and brood.