A new study says air pollution – especially that from car exhaust – may be a significant cause of rising rates of autism in children.

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 the journal Brain medicine.

“NO” is a common air pollutant produced mainly by vehicle emissions and the burning of fossil and industrial fuels. Exposure to NO and its derivative NO2 during pregnancy and early childhood may disrupt normal brain development,” the study authors wrote.

“The timing of his exposure is crucial. Exposure to these pollutants during pregnancy and early postnatal development poses a significant risk of ASD, as these periods are critical 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, such as ozone, fine particulate matter and other emissions, and found that together, these environmental toxins increase the risk of autism.

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

The way it works, the authors found, is that toxins in the environment cause inflammation, and “prolonged neuroinflammation triggered by NO exposure has been shown to influence the activity of brain regions involved in social and cognitive functions that are typically affected in ASD.”

As the study authors explained, “exposure to air pollution 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 infants during early life are associated with poorer neurodevelopmental outcomes.

American Lung Association Air condition The report found that nearly 40 percent of Americans live in places with “unhealthy levels of air pollution.”

According to the latest data from US Centers for Disease Control, 1 in 36 children has been diagnosed with ASD – an increase from 1 of 44 just two years before.

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