Air pollution linked to higher autism risk in children: Study

The study highlights specific pollutants, including nitrogen oxides and particulate matter.

PUBLISHED NOV 12, 2024

In cities like Phoenix, which ranks among the worst in the US for air pollution, residents are particularly susceptible to high levels of pollutants.

Phoenix, Arizona: Air pollution exposure during pregnancy may elevate the risk of children developing autism spectrum disorder (ASD), according to new research by Dr Haitham Amal and his team at the Hebrew University of Jerusalem.

The study highlights specific pollutants, including nitrogen oxides and particulate matter, commonly found in Arizona’s urban areas like Phoenix, that could play a significant role in autism risk when combined with genetic factors.

Originally established to curb volatile organic compound emissions, Rule 338 will now incorporate additional controls for nitrogen oxide (NOx) emissions.

This study comes as autism rates continue to rise globally and in the US, where approximately three in every 100 children are now diagnosed with ASD. The researchers reviewed a combination of studies involving both human cells and animal models to understand how pollutants affect brain development.

Dr. Amal’s focus was on nitric oxide (NO), a gas prevalent in emissions from car exhaust and industrial processes. When inhaled, NO and other pollutants can enter the bloodstream, cross protective brain barriers, and cause inflammation, potentially disrupting neural development.

Prevalence estimates by sex (Source: CDC)

In cities like Phoenix, which ranks among the worst in the US for air pollution, residents are particularly susceptible to high levels of pollutants like nitrogen oxides, sulfur dioxide, and particulate matter. These pollutants are generated by heavy traffic, industrial activity, and desert dust, and Arizona's climate can exacerbate air quality issues, leading to frequent high-pollution days.

According to the American Lung Association, 39% of Americans live in regions with hazardous air quality, exposing vulnerable populations like pregnant women and young children to increased health risks.

Prevalence estimates by Race/Ethnicity (Source: CDC)

Dr. Amal’s team suggests that early exposure to air pollution could disrupt the production of brain-regulating chemicals such as dopamine and norepinephrine, essential for cognitive development and behavior. Exposure to these pollutants may also influence gene expression in ways that heighten autism risk.

Harvard research supports these findings, indicating that exposure to particulate matter can increase autism risk by up to 64% during early childhood and by 31% during pregnancy.