New U.S. research has found that children with asthma who grow up in areas of high air pollution may need emergency medical treatment more often than asthmatics living in less polluted areas.

Carried out by researchers at Columbia University and published in the journal Pediatric Research, the new study looked at 190 children aged seven and eight growing up in four New York City neighbourhoods: the Bronx, Brooklyn, Queens, and Manhattan.

All the children had been diagnosed as having asthma before the study, and were grouped as living in neighbourhoods with high numbers of asthma cases or neighbourhoods with a low rate of asthma.

The researchers also assessed the annual average nitrogen dioxide (NO2), particulate matter (PM2.5), elemental carbon (EC), summer average ozone (O3), winter average sulfur dioxide (SO2) concentrations in the areas, before looking at the association between exposure to these pollutants and seeking urgent asthma care.

The findings showed that all pollutants, except O3 were higher in areas with a high number of asthma case than in areas where asthma was less common.

In addition, children living in neighborhoods where asthma was more common, and where levels of pollution was also higher, needed emergency care more often and were more like to suffer from exercise-induced wheezing.

However, lead author Stephanie Lovinsky-Desir, adds that even in neighbourhoods where asthma cases in children are less common, it is still important to make efforts to improve air quality.

Previous research has also linked exposure to air pollution to an increased risk of asthma in both children and adults and found that growing up near green spaces could reduce the risk of experiencing respiratory problems later in adult life.