Chlorpyrifos, a common farming pesticide that’s been in use since 1965, has been banned by the Biden administration and the Environmental Protection Agency (EPA). The pesticide has been linked to neurological damage in children, including reduced IQ, memory loss and attention deficit disorders. Pregnant people exposed to the pesticide may have negative birth outcomes.

Environmental Protection Agency officials issued a final ruling on Wednesday, stating that chlorpyrifos can no longer be used on food in the U.S. Chlorpyrifos is one of the most commonly used pesticides, and is typically applied to corn, soybeans, apples, broccoli, asparagus and other produce.


The new ruling will take effect in six months—according to The New York Times, labor and environmental advocacy groups estimate that the decision will eliminate more than 90% of chlorpyrifos use in the country. Many of these advocacy groups have been protesting the use of the pesticide for years.

The EPA was considering a ban on chlorpyrifos use a few years ago, but under the Trump administration, the agency declined to ban its use. Environmental organizations, health advocates, and advocacy groups that represent farm workers have all tried to stop the use of chlorpyrifos after many studies showed exposure to the pesticide could lead to lower birth weights, reduced I.Q.s and other developmental problems in children. Studies traced some of those health effects to prenatal exposure to the pesticide.

Even low to moderate levels of exposure to the insecticide chlorpyrifos during pregnancy may lead to long-term, potentially irreversible changes in the brain structure of the child, according to an MRI study conducted by researchers at Columbia Center for Children’s Environmental Health at the Mailman School of Public Health, Duke University Medical Center, Emory University, and the New York State Psychiatric Institute.

The changes in brain structure are consistent with cognitive deficits found in children exposed to this chemical. The study is the first to use MRI to identify the structural evidence for these cognitive deficits in humans, confirming earlier findings in animals. Changes were visible across the surface of the brain, with abnormal enlargement of some areas and thinning in others. The disturbances in brain structure are consistent with the IQ deficits previously reported in the children with high exposure levels of chlorpyrifos, or CPF, suggesting a link between prenatal exposure to CPF and deficits in IQ and working memory at age 7.

“Today E.P.A. is taking an overdue step to protect public health,” the agency’s head, Michael S. Regan, said in a statement. “Ending the use of chlorpyrifos on food will help to ensure children, farmworkers, and all people are protected from the potentially dangerous consequences of this pesticide.”

The pesticide is harmful to farmworkers in addition to those who ingest it via purchased produce—pregnant people and parents are particularly vulnerable, according to Elizabeth Strater, director of strategic campaigns for United Farm Workers of America.

“They don’t hug their kids until they change clothes, they wash their laundry separately,” Strater told the Times. “When they miscarry, or when their children have birth defects or learning disabilities, they wonder if their work exposures harmed their children.”

In a statement, EPA Administrator Michael Regan called the banning of chlorpyrifos an “overdue step to protect public health from the potentially dangerous consequences of this pesticide.”

“After the delays and denials of the prior administration, EPA will follow the science and put health and safety first,” Regan said.