A recent study has found that exposure to chlorpyrifos (CPF), a common insecticide, before birth can lead to lasting changes in children’s brain structure and reduced motor skills. These effects were observed in children and teenagers living in New York City.
The research, carried out by scientists from Columbia University Mailman School of Public Health, Children’s Hospital Los Angeles, and the Keck School of Medicine of USC, is the first to show that prenatal CPF exposure can cause long-term molecular, cellular, and metabolic changes in the human brain. The findings were published in the medical journal JAMA Neurology.
How the Study Was Done
The study followed 270 children who were part of the Columbia Center for Children’s Environmental Health birth cohort. These children were born to mothers of Latino and African-American backgrounds in New York City. At birth, each child had detectable levels of CPF in their umbilical cord blood. Later, between the ages of 6 and 14, these children underwent brain scans and behavioural tests.
The results clearly showed that children with higher levels of CPF exposure before birth had more noticeable differences in their brain structure and function. They also performed less well on tests measuring how quickly they could move and how well they could coordinate their bodies.
This evidence suggests that exposure to CPF before birth disrupts brain structure, function, and metabolism. The extent of this disruption seems to be directly related to the amount of exposure.
Widespread Exposure and Ongoing Risks
For the children in this study, the main way they were exposed to CPF was through indoor pesticide use. It’s important to note that the U.S. Environmental Protection Agency banned CPF for home use in 2001. However, it is still used in farming for non-organic produce and grains.
Because it’s still used in agriculture, farm workers and people living near farms can still be exposed. This can happen through contaminated air and dust. “Current widespread exposures, at levels comparable to those experienced in this sample, continue to place farm workers, pregnant women, and unborn children in harm’s way,” said Dr. Virginia Rauh, a senior author of the study.
She added, “It is vitally important that we continue to monitor the levels of exposure in potentially vulnerable populations, especially in pregnant women in agricultural communities, as their infants continue to be at risk.”
Dr. Bradley Peterson, the first author of the study, explained, “The disturbances in brain tissue and metabolism that we observed with prenatal exposure to this one pesticide were remarkably widespread throughout the brain.” He believes that other organophosphate pesticides likely have similar effects. He stressed the importance of caution to minimize exposure during pregnancy, infancy, and early childhood, periods when the brain is developing rapidly and is most vulnerable to toxic chemicals.
The research team included many contributors from different institutions. Financial support for this project came from several sources, including the National Institute of Environmental Health Sciences, the U.S. Environmental Protection Agency STAR program, and the National Institute of Mental Health. Additional funding was provided by several foundations and donors.
Some researchers reported potential conflicts of interest, such as stock options or patents related to psychiatric health. However, all other researchers stated they had no conflicts of interest.