The U.S. Environmental Protection Agency (EPA) announced a preliminary pollinator risk assessment for the neonicotinoid insecticide, Imidacloprid, which the federal government says shows a threat to some pollinators.

The EPA’s assessment, prepared in collaboration with California’s Department of Pesticide Regulation (DPR), indicates that Imidacloprid presents a potential 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. These effects can include a decline in total pollinator numbers and a reduction in honey production.

For example, data show 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 EPA identified level. Additional data is being generated on these and other crops to help 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 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.

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 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.

The risk assessment and other supporting documents will be available online in the docket.

EPA is also planning a webinar on the Imidacloprid assessment in early February. Times and details will be posted online.

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