EPA study says pesticides pose risk to honeybees; critics call study flawed

Neonicotinoids, a widely used pesticide used on crops that attract pollinators, poses a risk to honeybees, said a study released Wednesday by the Environmental Protection Agency. "The preliminary risk assessment identified a residue level for imidacloprid of 25 ppb, which sets a threshold above which effects on pollinator hives are likely to be seen—and at that level and below which effects are unlikely. These effects include decreases in pollinators as well as less honey produced." EPA in 2015 proposed banning pesticides, including neonicotinoids, that are harmful to bees, which are responsible for more than $15 billion in increased crop value each year. (Bee Informed graphic)

The study, the first of four to be conducted by EPA, "focused primarily on the best known and most economically important species, the Western honey bee (Apis mellifera), and said more study was needed to fully evaluate the effects of imidacloprid on all pollinators," Stephen Davies reports for Agri-Pulse. "Preliminary assessments for clothianidin, thiamethoxam and dinotefuran are scheduled to be released for public comment in December 2016. A preliminary risk assessment of all ecological effects for imidacloprid, including a revised pollinator assessment and impacts on other species such as aquatic and terrestrial animals and plants, will also be released in December 2016, EPA said."

The EPA study has already been criticized, with the The Center for Biological Diversity—which has sued EPA to force it to conduct assessments of pesticide risks—saying the analysis was flawed in numerous ways, Davies writes. Also, Bayer CropScience, a major manufacturer and registrant of imidacloprid, said in a statement: “We will review the EPA document, but at first glance it appears to overestimate the potential for harmful exposures in certain crops, such as citrus and cotton, while ignoring the important benefits, these products provide and management practices to protect bees. We hope the final risk assessment is based on the best available science as well as a proper understanding of modern pest management practices.” (Read more)