Background: Recently, cyantraniliprole (CYA) and sulfoxaflor (SUL) have been considered as alternatives to neonicotinoid insecticides. In this study, we evaluated the acute and chronic toxicities of CYA and SUL on honey bee (Apis mellifera L.) larvae reared in vitro.
Results: In the acute toxicity test, the following test doses were used to determine the median lethal dose (LD50 ): CYA 0.007, 0.014, 0.028, 0.056 and 0.112 μg larva-1 ; SUL 2.5, 5, 10, 20 and 40 μg larva-1 . In the chronic toxicity test, the following test doses were used to determine the LD50 : CYA 0.00512, 0.0128, 0.032, 0.08 and 0.2 μg larva-1 ; SUL 0.0625, 0.125, 0.25, 0.5 and 1.0 μg larva-1 . The acute LD50 values of CYA and SUL were 0.047 and 11.404 μg larva-1 , respectively. Larvae acutely exposed to SUL had significantly lower body weight than controls, but those exposed to CYA showed no difference. The no observed adverse effect level (NOAEL) and LD50 values of the chronic toxicity tests for each insecticide were 0.00512 and 0.064 μg larva-1 for CYA, and 0.0625 μg larva-1 and 0.212 μg larva-1 for SUL, respectively. Larvae chronically exposed to SUL emerged as bees with deformed wings, reaching adult deformation rates of over 50%; however, CYA had no effect on adult deformation.
Conclusion: Exposure to CYA increased larval mortality but did not cause any adult deformation, whereas SUL exposure increased pupal mortality and caused wing deformation in newly emerged bees. Our study may be useful for the assessment of pesticide toxicity by providing valuable findings on the effects of these insecticides on honey bee larvae. © 2022 Society of Chemical Industry.
Keywords: Cyantraniliprole; honey bee larvae; sulfoxaflor; toxicity assessment.
© 2022 Society of Chemical Industry.