Air pollution may increase risk of a child developing autism

Air pollution may increase risk of a child developing autism

Pollutants a pregnant woman is exposed to may influence fetal brain development.

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Published: November 12, 2024 at 8:57 am

Researchers have discovered air pollution could increase a child’s risk of developing autism spectrum disorder (ASD). Specifically, a new study reveals a pregnant woman’s exposure to common air pollutants could have a drastic effect on her fetus’ brain during critical development periods.

"Different kinds of neurological disorders, including autism spectrum disorder, can be associated with [pollutants]," explained Professor Haitham Amal, senior author of the study. 

"The timing of exposure appears crucial, with heightened vulnerability during prenatal development.”

The research, published in Brain Medicine, suggests ultra-small pollutants known as ‘fine particulate matter’ and nitrogen oxides (NO) impact a young brain the most. While some of these pollutants are naturally occurring in the atmosphere, they also come from transport and fossil fuels

Researchers argue these findings seem to be especially relevant to individuals with a genetic predisposition for autism. That’s to say, people whose genes indicate they are more likely to develop the neurological and developmental disorder. As high as 80 per cent of autism cases are believed to be hereditary

"This interaction between genetic and environmental factors opens new avenues for understanding ASD's complex [causes],” said Amal. 

Scientists suggest the pollutants can cross the placenta and affect a fetus’ brain growth. They have proposed a few pathways where these pollutants could disrupt the body – including how it transmits chemical messages between nerves, chemical reactions and the hormone system. 

Around 1-1.5 per cent of the global population has autism spectrum disorder. Outside of this study, scientists are yet to conclude what causes autism. Experts theorise various genes may play a factor in the condition, but some evidence suggests environmental factors may play a role.

The researchers hope their findings will encourage health professionals to take protective steps for pregnant women living in areas with high pollution.

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