Toxicity of formulated systemic insecticides used in apple orchard pest management programs to the honey bee (Apis mellifera (L.))

Authors: HELLER, SARAH - Pennsylvania State University; Fine, Julia; PHAN, NGOC - Vietnam Nationall University; RAJOTTE, EDWIN - Pennsylvania State University; BIDDINGER, DAVIS - Pennsylvania State University; JOSHI, NEELENDRA - University Of Arkansas

Submitted to: Environments
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/6/2023
Publication Date: 7/11/2022
Citation: Heller, S., Fine, J.D., Phan, N., Rajotte, E., Biddinger, D., Joshi, N. 2022. Toxicity of formulated systemic insecticides used in apple orchard pest management programs to the honey bee (Apis mellifera (L.)). Environments. 9(7). Article 90. https://doi.org/10.3390/environments9070090.
DOI: https://doi.org/10.3390/environments9070090

Interpretive Summary: Honey bees are one of the most important pollinating insects, but recently, populations of honey bees have been declining due to a combination of factors like the widespread use of agricultural pesticides. Laboratory studies were conducted to determine the oral toxicity of different pesticide products to honey bee adults. In particular, we assessed the toxicity of two neonicotinoids (acetamiprid, Assail 30SG and thiamethoxam, Actara 25WDG) and two other systemic insecticide products (sulfoxaflor, Closer 2SC and flupyradifurone, Sivanto 200SL) upon ingestion, all of which are generally used in pest management programs in commercial apple orchards in the eastern United States. Honey bees were fed a range of doses of each pesticide in order to create a response curve, and LC50, LC90, and LD50 values were determined. The pesticide formulation containing flupyradifurone as the active ingredient was found to be the least toxic to honey bees followed by the formulations containing sulfoxaflor and acetamiprid. The toxicity values obtained in this study are different from other studies using only technical active ingredients, suggesting the need to evaluate formulated products while conducting risk assessment.

Technical Abstract: Honey bees (Apis mellifera) are one of the most important pollinating species of flowering plants. Recently, populations of honey bees have been declining due to a combination of factors, including the widespread use of agricultural pesticides. Laboratory studies were conducted to determine the acute oral toxicity of different formulated pesticides to honey bee adults. In particular, we assessed the acute oral toxicity of two neonicotinoids (acetamiprid, Assail 30SG and thiamethoxam, Actara 25WDG) and two other systemic insecticide products (sulfoxaflor, Closer 2SC and flupyradifurone, Sivanto 200SL), all of which are generally used in pest management programs in commercial apple orchards in the eastern United States. Honey bees were fed a range of doses of each pesticide in order to create a response curve, and LC50, LC90, and LD50 values were determined. The pesticide formulation containing flupyradifurone as the active ingredient was found to be the least toxic to honey bees followed by the formulations containing sulfoxaflor and acetamiprid. The toxicity values obtained in this study differ from other studies using only technical active ingredient compound, suggesting the need to evaluate formulated products while conducting risk assessment.