New research supports the growing belief that prenatal and early childhood exposure to air pollution negatively affects cognitive development. The study, from the Barcelona Institute for Global Health, concludes that exposure to tiny particulate matter — 2.5 micrometers in diameter or smaller (PM2.5) — during gestation and the first years of life is associated with impaired working memory and executive attention.
The study included 2,221 Barcelona school children between 7 and 10 years old. Students’ cognitive abilities were assessed via computer testing and air pollution exposure was estimated by a mathematical model using real measurements.
High levels of particulate exposure were correlated with reduced executive attention in both boys and girls. Executive attention is critical to many aspects of attention capacity, including error detection, emotional regulation and response inhibition.
Greater exposure to PM2.5 correlated with lower scores on working memory tests, but this was true only for boys. This unexpected discovery led researchers to theorize that “hormonal or genetic mechanisms” could protect girls from the toxicity and inflammatory processes triggered by the particulate matter.
As co-author Dr. Jordi Sunyer observed, “This study reinforces our previous findings and confirms that exposure to air pollution at the beginning of life and throughout childhood is a threat to neurodevelopment and an obstacle that prevents children from reaching their full potential.”