A week before a federal court deadline to make a final decision on its use, the US Environmental Protection Agency (EPA) has denied a petition to ban the insecticide active ingredient chlorpyrifos, calling it “crucial to U.S. agriculture.” The agency said it will continue to review the science addressing neurodevelopmental effects of chlorpyrifos as part of the ongoing registration review and complete its assessment of the chemical by the statutory deadline of Oct. 1, 2022.

Chlorpyrifos is used on corn, strawberries, wheat, citrus, apples, broccoli and a number of other crops, as well as on golf courses, turf and in greenhouses. The US blocked its residential use in 2000. It is also restricted in wildlife areas.

In October 2015, the EPA proposed to revoke all food residue tolerances for the insecticide ingredient, acting on a petition from the Natural Resources Defense Council (NRDC) and Pesticide Action Network North America filed in 2007. Capping years of litigation, the environmental watchdog in November 2016 released an assessment of chlorpyrifos, concluding that current usage carries dietary and drinking water risks. It said also that the residues on food crops exceed safety standards and that there are risks to workers who apply the insecticide.

Quoting “serious scientific concerns and substantive process gaps,” new EPA Administrator Scott Pruitt, an appointee of President Donald Trump, said the 2015 proposal to ban the chemical “largely relied on certain epidemiological study outcomes, whose application is novel and uncertain. Reliable data, overwhelming in both quantity and quality, contradicts the reliance on – and misapplication of – studies to establish the end points and conclusions used to rationalize the ban,” he asserted.

In the past Dow Chemical, which manufactures the insecticide under the name Lorsban, pressed to keep the product in use, claiming the science was not conclusive. The chemical producer did not comment on the EPA’s move, but Pruitt argued that the government “needs to provide regulatory certainty to the thousands of American farms that rely on chlorpyrifos, while still protecting human health and the environment. We are returning to using sound science in decision-making – rather than predetermined results.”

Sheryl Kunickis, current director of the Office of Pest Management Policy at the US Department of Agriculture (USDA), welcomed the overturn of the 2015 proposal, saying “it means that this important pest management tool will remain available to growers, helping to ensure an abundant and affordable food supply for this nation and the world.”

In the director’s view – Congress has not yet confirmed Trump’s pick for new Secretary of Agriculture, former Georgia governor, Sonny Perdue – “this frees American farmers from significant trade disruptions that could have been caused by an unnecessary, unilateral revocation of chlorpyrifos tolerances in the United States. It is also great news for consumers, who will continue to have access to a full range of both domestic and imported fruits and vegetables.”

The original petitioners have filed a complaint against the Pruitt decision, seeking to force the government to follow through with the ban. According to the environmental groups, research shows that use of the insecticide is correlated with lower IQ, attention deficit disorders and developmental delays. The new complaint, filed by advocacy group Earthjustice, asks a panel of three federal appeals court judges to order the EPA to permanently ban chlorpyrifos based on its own science.