WASHINGTON (AP) — The Trump administration won’t ban a common pesticide used on food, reversing efforts by the Obama administration to bar the chemical based on findings it could hinder development of children’s brains.

In announcing the decision late Wednesday, Environmental Protection Agency Administrator Scott Pruitt said that by not banning chlorpyrifos, he was providing “regulatory certainty” to thousands of American farmers that rely on the pesticide.

“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,” Pruitt said Wednesday.

In approving the continued use of chlorpyrifos on citrus fruits, apples, cherries and other crops, Pruitt is overriding the scientific findings of his own agency’s experts. Pruitt, a Republican lawyer who took the lead at EPA last month, gave no indication of what process he used to determine chlorpyrifos is safe.

Environmental groups accused Pruitt of putting the profits of big business over public safety.

“EPA’s refusal to ban this dangerous pesticide is unconscionable,” said Patti Goldman, an attorney at Earthjustice. “EPA is defying its legal obligation to protect children from unsafe pesticides.”

Goldman said her group will seek a court to order to countermand Pruitt’s decision.

First developed as a chemical weapon prior to World War II, chlorpyrifos has been sold as a pesticide since 1965 and has been blamed for sickening dozens of farmworkers in recent years. Traces have been found in waterways, threatening fish, and experts say overuse could make targeted insects immune to the pesticide.

U.S. farms use more than 6 million pounds of the chemical each year — about 25 percent of it in California.

Under pressure from federal regulators over safety concerns, Dow withdrew chlorpyrifos for use as a home insecticide in 2000. EPA also placed “no-spray” buffer zones around sensitive sites, such as schools, in 2012.

But environmental and public health groups said those proposals don’t go far enough and filed a federal lawsuit seeking a national ban on the pesticide.

In October 2015, the Obama administration proposed revoking the pesticide’s use in response to a petition from the Natural Resources Defense Council and Pesticide Action Network North America.

EPA’s subsequent findings relied on three, peer-reviewed human health studies indicating that even minuscule amounts of chlorpyrifos, sold by Dow Chemical, can interfere with brain development of fetuses, infants and children.

“There is a breadth of information available on the potential adverse neurodevelopmental effects in infants and children as a result of prenatal exposure to chlorpyrifos,” said a risk assessment memo issued in November by nine EPA scientists.

The EPA said then that its analysis did not suggest risks from residual exposure to chlorpyrifos in food. But when those exposures are combined with estimated exposure from drinking water in certain watersheds, “EPA cannot conclude that the risk from aggregate exposure meets the Federal Food, Drug and Cosmetic Act safety standard,” it said.

Now under new management, the EPA said Wednesday that the previous administration’s proposal relied on a study “whose application is novel and uncertain, to reach its conclusions.”

“The public record lays out serious scientific concerns and substantive process gaps in the proposal,” the agency said. “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 proposal.”

The Dow Chemical subsidiary that sells chlorpyrifos quickly issued a statement praising Pruitt’s decision.

“Dow AgroSciences remains confident that authorized uses of chlorpyrifos products offer wide margins of protection for human health and safety,” the company said in a statement.

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Rodriguez reported from San Francisco.

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