By Abbas Nazil
Babies born to mothers exposed to higher levels of air pollution during pregnancy show slower brain myelination — a key process in early brain development, a Spanish research has found out.
Published in Environment International, the research examined 93 newborns born in Barcelona between 2018 and 2021, revealing that prenatal exposure to fine particulate matter (PM2.5) may delay the formation of myelin, the protective sheath that enables faster and more efficient brain communication.
Researchers used magnetic resonance imaging (MRI) on the infants at around one month of age to measure brain volume and myelination.
They discovered that higher PM2.5 exposure in early pregnancy was linked to reduced cortical myelination, while later exposure was associated with lower overall myelination.
No significant association was found with brain volume, suggesting that air pollution may specifically disrupt the wiring rather than the size of the brain.
Particulate matter such as PM2.5 can cross the blood-brain barrier and affect neural development.
It contains both toxic pollutants and trace metals like iron, copper, and zinc — essential for brain growth — making its effects complex and potentially contradictory.
Lead author Dr. Jordi Pujol explained that these findings highlight how environmental factors can subtly alter early brain maturation.
Although the study shows signs of slower myelination, researchers caution that this may not necessarily result in permanent damage since brain development continues rapidly in the first years of life.
In some cases, slower early myelination has been linked to higher cognitive abilities later, suggesting that the impact may depend on multiple factors including nutrition and postnatal environment.
The study underscores the need for stronger air quality policies and long-term monitoring to understand how prenatal pollution exposure may influence children’s cognitive and behavioral outcomes.
Researchers emphasized that cleaner air is crucial for ensuring healthy brain development from the earliest stages of life.
