The research was published in the journal “Environment International” and is only the latest in a long series of studies proving the negative impact of air pollution on brain development, during the first years of life and, even earlier, during pregnancy.
Using data from more than 1,700 women and their children, selected in four regions of Spain, the researchers estimated daily exposure to NO2 during pregnancy and in the first six years of childhood.
At the same time, they assessed attentional function (a term from cognitive psychology meaning the ability to choose what to pay attention to and what to ignore) at 4–6 and at 6–8 years. And working memory (the ability to hold information temporarily) at 6–8 years, using computer tests.
The results showed fairly clearly that children exposed to higher levels of NO2 are more likely to have poorer attentional function at 4–6 years, and that at the age of 2 they are more sensitive to this pollutant.
The link between air pollution and attention capacity was also found by the Barcelona Institute for Global Health (ISGlobal) in children aged 6–8.
What causes do the researchers suggest?
Attentional function underlies the development of the executive functions of our brain, which control actions, thoughts and emotions.
“The prefrontal cortex, the part of the brain responsible for executive functions, develops slowly and is fully maturing during pregnancy and childhood”, explains Anne-Claire Binter, one of the study’s authors.
This is why it is more vulnerable to exposure to air pollution, which causes inflammation, oxidative stress and alteration of energy metabolism in the brain area.
Another striking finding is that boys appear more vulnerable than girls. “In boys, the association between NO2 exposure and attentional function may last longer because their brains mature more slowly. This may be the reason for their greater vulnerability”, explains Binter.
“This study suggests that early childhood, up to the age of 2, seems to be the period on which to focus preventive measures”, Binter adds. “Because even a small effect at individual level resulting from relatively low exposure levels can have major consequences at population level”.
The results of the Spanish study are therefore one more reason to act immediately and with the utmost seriousness on the crucial problem of reducing pollution, in this case for the benefit of our children’s health.
It may be worth recalling that, according to the shock report published in 2023 by the European Environment Agency (EEA), every year in Europe more than 1,200 children and adolescents die from causes linked to air pollution:
https://www.agi.it/scienza/news/2023-04-26/inquinamento_quanti_bambini_muoiono_europa-21100267/#:~:text=AGI%20%2D%20Secondo%20l'ultimo%20rapporto,salute%20fisica%20e%20mentale%20con
And that, as Gerardo Sanchez Martinez, an environment and health expert at the EEA, has pointed out, “when it comes to air pollution, children cannot be thought of as small adults. They suffer more from it, already during pregnancy, and feel its effects later at nursery and beyond. We are failing our children on air pollution”.
