Autism May Be Caused by Air Pollution — Specifically, Car Exhaust, New Study Says

Mar. 15, 2025

Stock image of a child playing with blocks.Photo:Liudmila Chernetska/Getty

Liudmila Chernetska/Getty

Exposure to nitric oxide (NO)— which is produced when fuel is burned — while a mother is pregnant, or in the early months of life, may pose a “significant risk” of a child developing Autism Spectrum Disorder (ASD), according to a study published Nov. 12 in in the journalBrain Medicine.

Stock image of an exhaust pipe.Toa55/Getty

Toa55/Getty

“The timing of its exposure is crucial. Exposure to these pollutants during pregnancy and early postnatal development poses a significant risk of ASD since these periods are essential for brain development.”

The study pointed out that “individuals with a genetic predisposition to ASD may be more vulnerable to the harmful effects of NO exposure.”

The study also looked at other air pollutants, like ozone, fine particles, and other emissions, and found that together, these environmental toxins increase the risk of autism.

“Benzeneis a volatile organic compound commonly found in vehicle emissions, industrial processes, and tobacco smoke. Maternal exposure to NO2 and benzene during pregnancy can also increase the risk of ASD,” the study authors wrote.

Stock image of a truck on the highway.clemspictures/Getty

clemspictures/Getty

As the study authors explained, “air pollution exposure during pregnancy can activate the mother’s immune system, leading to inflammation and altered fetal brain development. Elevated concentrations of inflammation-related cytokines in maternal serum in utero and children during their early life are associated with worse neurodevelopmental outcomes.”

The American Lung Association’sState of the Airreport found that nearly 40% of Americans live in places with “unhealthy levels of air pollution.”

According to the most recent data from theU.S. Centers for Disease Control,1 in 36 children have been diagnosed with ASD — an increase from1 in 44just two years prior.

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source: people.com