Polluted city neighborhoods are bad news for asthmatic children

For this study, 190 participants aged seven and eight were recruited between 2008 and 2011. All participants were part of the New York City Neighborhood Asthma and Allergy Study and had previously been diagnosed as having asthma. They all grew up in middle-income families in neighborhoods in the Bronx, Brooklyn, Queens, and Manhattan.

The participants were grouped as belonging to neighborhoods with high numbers of asthma cases or neighborhoods with low instances of asthma. There was no significant difference between the household incomes and access to health care (private insurance) enjoyed by the families of the participants. However, those growing up in areas where asthma was more common tended to live in apartment buildings or on higher floors. They were also more likely to live in crowded environments and be raised by single mothers.

Lovinsky-Desir and her colleagues found that children living in neighborhoods where asthma was more common needed emergency care more often and tended to suffer more from exercise-induced wheezing. Also, the concentrations of ambient pollutants in these neighborhoods were higher. Over the course of a year, concentrations of known air pollutants such as nitrogen dioxide, small airborne particles and elemental carbon were much higher in these neighbourhoods than in those with fewer asthma cases.

An interesting finding was that children living in neighborhoods where asthma was less common were effected most by pollution, even though pollution levels were higher in the more common asthma neighborhoods.

"In neighborhoods with less poverty, children exposed to air pollution were more likely to be taken for emergency asthma treatment. However, in neighborhoods with more poverty, it's likely that other things in the environment, such as stress and violence, have a stronger effect on urgent asthma treatment than air pollution," explains Lovinsky-Desir.