In one of his first major actions as head of the Environmental Protection Agency (EPA), Scott Pruitt has blocked a scheduled ban of the use of a pesticide that evidence has shown causes developmental damage to children’s brains.

Pruitt vetoed the ban – which had been a decade in the making after petitions from the Natural Resources Defence Council and Pesticide Action Network started back in 2007 – at the “eleventh hour” after the EPA itself proposed the ban based on its own scientific findings in 2015. The EPA was under court order to issue a final rule by the end of March this year.

The proposed ban on the use of chlorpyrifos, banned from use in US households but still widely used as a pesticide, was based on evidence provided by studies from Columbia University, University of California, Berkeley, and Mount Sinai Medical Center, among others that showed a link between cognitive impairment in children due to pre- and postnatal exposure to organophosphates.

After the EPA proposed the ban in October 2015, Croplife America, the United States’ biggest pesticide lobbying group, petitioned the EPA to block the ban. That Pruitt has come down on the side of pro-pesticide groups has incurred, if not surprise, then a scathing response from those seeking the ban.

“The Trump EPA’s denial of the NRDC and Pesticide Action Network 2007 petition to ban chlorpyrifos contradicts the EPA’s own analysis from November 2016 (just five months ago!) that found widespread risk to children from residues of the pesticide on food, in drinking water, and in the air in agricultural communities,” the Natural Resource Defense Council (NRDC) said in a statement on Wednesday, after the EPA’s announcement. “Up until last night, the EPA explained that because of these risks a ban was needed to protect children’s health.”

"The chance to prevent brain damage in children was a low bar for most of Scott Pruitt's predecessors, but it apparently just wasn't persuasive enough for an administrator who isn't sure if banning lead from gasoline was a good idea," chimed in Environmental Working Group President Ken Cook. "Instead, in one of his first major decisions as head of the EPA, like a toddler running toward his parents, Pruitt leaped into the warm and waiting arms of the pesticide industry."

Pruitt claimed in his own statement: “By reversing the previous Administration’s steps to ban one of the most widely used pesticides in the world, we are returning to using sound science in decision-making – rather than predetermined results.” The EPA has said that it will continue studying this chemical.

This doesn't mean those seeking the ban will give up though. Earthjustice, who serves as the legal team for the NRDC and Pesticide Action Network, claims that blocking the ban is not legal and they will fight Pruitt's decision in court. “We have a law that requires the EPA to ban pesticides that it cannot determine are safe, and the EPA has repeatedly said this pesticide is not safe,” Patti Goldman, managing attorney at Earthjustice, told The New York Times.