EPA is Advancing Pollinator Science and Sharing Useful Information with Growers and Beekeepers

At the request of beekeepers and growers alike, the agency has posted the Residual Time to 25% Bee Mortality (RT25) Data online. Bees may be susceptible to harm from direct exposure to pesticides sprayed on flowering plants, but pesticide residues generally decrease in toxicity as the spray dries and time passes. Farmers and beekeepers can use EPA’s RT25 data to gauge the amount of time after application that a particular pesticide product remains toxic enough under real-world conditions to kill 25 percent of bees that are exposed to residues on treated plant surfaces. Some have used this information to select pesticide products with shorter periods in which the chemicals remain active and can affect bees.