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• Young children nationwide are exposed to a large swath of possibly toxic chemicals before kindergarten, new research suggests

• “Our study shows that childhood exposure to potentially harmful chemicals is widespread. This is alarming because we know early childhood is a critical window for brain and body development,” said the study’s lead author, Deborah Bennett

• Researchers found that of the 111 chemicals they focused on, 48 were found in more than 50% of the children

Before ever stepping foot inside a kindergarten classroom, young children nationwide are already exposed to a large swath of possibly toxic chemicals, new research suggests.

The study, published in Environmental Science and Technology on Monday, June 30, analyzed chemical exposure in 201 kids from the ages of 2-4 years old between 2010 and 2021, using urine samples from the children and most of their mothers during pregnancy. Researchers focused on 111 chemicals.

“Our study shows that childhood exposure to potentially harmful chemicals is widespread. This is alarming because we know early childhood is a critical window for brain and body development,” said the study’s lead author, Deborah Bennett in a statement from UC Davis, where she is a professor.

“Many of these chemicals are known or suspected to interfere with hormones, brain development and immune function,” Bennett added.

Researchers found that of the 111 chemicals, 96 were detected in at least five kids and 48 were found in more than 50% of the children. In addition, 34 were found in more than 90% of the kids — including nine substances “which have not been included in U.S. national biomonitoring.”

“This study reveals frequent exposure to multiple chemicals in young U.S. children, often exceeding prenatal levels,” the authors wrote in a summary. “Expanded biomonitoring of emerging chemicals of concern and studies of their health effects in this vulnerable population are warranted.”

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According to UC Davis, the study found children were exposed to phthalates, parabens, bactericides, and various other chemicals through “everyday activities, such as eating, drinking, breathing indoor and outdoor air and touching contaminated surfaces.”

“Exposure to certain chemicals in early childhood, such as pesticides, plasticizers and flame retardants, has been linked to developmental delays, hormone disruption and other long-term health issues,” the study’s first author, Jiwon Oh, told UC Davis.

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