WASHINGTON, D.C., — The U.S. Environmental Protection Agency (EPA) announced a preliminary pollinator risk assessment for the neonicotinoid insecticide, imidacloprid, which shows a threat to some pollinators. EPA’s assessment, prepared in collaboration with California’s Department of Pesticide Regulation, indicates that imidacloprid potentially poses risk to hives when the pesticide comes in contact with certain crops that attract pollinators.

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.

For example, research shows that citrus and cotton may have residues of the pesticide in pollen and nectar above the threshold level. Other crops such as corn and leafy vegetables either do not produce nectar or have residues below the level. Additional data is being generated on these and other crops to help the EPA evaluate whether imidacloprid poses a risk to hives.

The imidacloprid assessment is the first of four preliminary pollinator risk assessments for the neonicotinoid insecticides. Preliminary pollinator risk assessments for three other neonicotinoids: clothianidin, thiamethoxam and dinotefuran, are scheduled to be released 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.

In addition to working with California, EPA coordinated efforts with Canada’s Pest Management Regulatory Agency.

Canada’s Imidacloprid pollinator-only assessment reaches the same preliminary conclusions as EPA’s report.

The 60-day public comment period will begin upon publication in the Federal Register. After the comment period ends, EPA may revise the pollinator assessment based on comments received and, if necessary, take action to reduce risks from the insecticide.

In 2015, EPA proposed to prohibit the use of pesticides that are toxic to bees, including the neonicotinoids, when crops are in bloom and bees are under contract for pollination services. The Agency temporarily halted the approval of new outdoor neonicotinoid pesticide uses until new bee data is submitted and pollinator risk assessments are complete.

EPA encourages stakeholders and interested members of the public to visit the imidacloprid docket and sign up for email alerts to be automatically notified when the agency opens the public comment period for the pollinator-only risk assessment. The risk assessment and other supporting documents will be available here. EPA is planning a webinar on the imidacloprid assessment in early February 2016.