Pesticides in Honey Bee Colonies: Establishing a baseline for real world exposure over seven years in the USA

Authors: TRAYNOR, KIRSTEN - University Of Maryland; TOSI, SIMONE - French Agency For Food, Environmental And Occupational Health & Safety (ANSES); RENNICH, KAREN - University Of Maryland; STEINHAUER, NATHALIE - University Of Maryland; FORSGREN, EVA - Swedish University Of Agricultural Sciences; ROSE, ROBYN - US Department Of Agriculture (USDA); KUNKEL, GRACE - University Of Maryland; Madella, Shayne; Lopez, Dawn; EVERSOLE, HEATHER - University Of Maryland; FAHEY, RACHEL - University Of Maryland; PETTIS, JEFFERY - Retired ARS Employee; Evans, Jay; VANENGELSDORP, DENNIS - University Of Maryland

Submitted to: Environmental Pollution
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/19/2021
Publication Date: 5/15/2021
Citation: Traynor, K.S., Tosi, S., Rennich, K., Steinhauer, N., Forsgren, E., Rose, R., Kunkel, G., Madella, S., Lopez, D.L., Eversole, H., Fahey, R., Pettis, J., Evans, J.D., Vanengelsdorp, D. 2021. Pesticides in Honey Bee Colonies: Establishing a baseline for real world exposure over seven years in the USA. Environmental Pollution. 279. https://doi.org/10.1016/j.envpol.2021.116566.
DOI: https://doi.org/10.1016/j.envpol.2021.116566

Interpretive Summary: Honey bee colonies, and beekeepers, are challenged by parasites, pathogens, pesticides, and poor nutrition. It is difficult to measure the long-term impacts of these factors and their interactions. Survey data, such as from the USDA-APHIS Honey Bee Health Survey, can provide insights into the colony impacts of disease and stress. This study combines multi-year survey data with risk analyses based on colony losses. Chemicals used to treat mites in honey bee hives were widespread and impactful, as were pesticides. The results can help direct needed research and inform beekeepers, growers, and regulatory agencies.

Technical Abstract: Evaluating pesticide exposure risk to pollinators is an ongoing problem. Here we apply five metrics for pesticide exposure risk (prevalence, diversity, concentration, significant pesticide prevalence, and hazard quotient (HQ)) to a nation-wide field study of honey bees, Apis mellifera. Pesticides in pollen were highly prevalent and variable across states. While pesticide diversity increased over time, most detections occurred at levels predicted to be of low risk to colonies. Varroacides contributed most to concentration, followed by fungicides, while insecticides were the main contributor to significant pesticide diversity. High risk samples contained one of 12 different insecticides/varroacides. Exposures predicted to be low-risk were nevertheless associated with colony morbidity, and low-level fungicide exposures were tied to queen loss, Nosema infection, and brood diseases.