A new study shows that exposure to air pollution is associated with reduced attention span in children, especially when it occurs during the first two years of life.
- Exposure to nitrogen dioxide during the first two years of life is associated with lower attention span in children aged 4 to 8 years.
- The risk was higher if exposure to high levels occurred during early childhood.
- Boys are more impacted by exposure to the pollutant.
Asthma, allergies, eczema, obesity… air pollution is linked to an increased risk of several diseases in children. But the list of harmful effects on children does not end there, according to a study carried out by the Barcelona Institute for Global Health (ISGlobal) and published in the journal Environment International.
Exposure to nitrogen dioxide (NO2), gas emitted by gasoline and diesel vehicles, was associated with poorer attentional functions in school-age children. The risk of a reduced attention span was even greater when the little ones faced this pollutant during the first two years of their life.
Children’s attention span: it is impacted by nitrogen dioxide
To assess the impact of NO2 on children, researchers followed 1,703 women and their offspring from four Spanish regions. They calculated exposure to the pollutant during pregnancy and the first six years of childhood using their home address. In addition, attentional function – that is, the child’s ability to choose what to pay attention to and what to ignore – was measured at ages 4-6 and 6-8 years. Between ages 6 and 8, the children’s working memory was also tested.
Result: being exposed to high levels of NO2 was associated with lower attention span in children aged 4 to 6 years, “with increased susceptibility to this pollutant observed during the second year of life”. The association persisted between 6 and 8 years, but only in boys, “with a slightly longer period of susceptibility from birth to 2 years”.
On the other hand, no link has been demonstrated between higher exposure to NO2 and working memory in children aged 6 to 8 years.
“These findings highlight the potential impact of increased traffic-related air pollution on delayed development of attentional capacity and highlight the importance of further research into the long-term effects of air pollution in groups older”explains researcher Anne-Claire Binter in a communicated.
Pollution and attentional functions: repercussions on health
Why do boys seem to be impacted by air pollution for longer? “In boys, the association between exposure to N02 and attentional function could last longer because their brains mature more slowly, which could make them more vulnerable.”explains the author of the study.
Anne-Claire Binter also recalls that attentional functions are crucial for the development of executive functions of the brain. For her, the study shows that “early childhood, up to the age of 2, appears to be a relevant period for implementing preventive measures.”
“Even a small effect at the individual level due to relatively low exposure levels, as in this study, can have important consequences at the population level. Exposure to traffic-related air pollution is therefore decisive for health future generations”concludes the researcher.
