Many Children Worldwide Suffer Asthma Due To Early Traffic Exposure, Study Finds

Exposure to traffic-related air pollution has been found causing asthma in nearly four million children across the world. Due to alarming rates, researchers called on the World Health Organization to update its guideline in protecting children from pediatric asthma. 

The study published in the journal The Lancet Planetary Health highlights the impact of inhaling nitrogen dioxide from motor vehicle exhaust in 194 countries and 125 major cities worldwide. It shows that between 2010 and 2015, 64 percent of all new cases of asthma occurred in urban areas.

The researchers from the George Washington University Milken Institute School of Public Health said that NO2 pollution continued to contribute to pediatric asthma, causing an average of 13 percent of new cases annually around the globe. 

For the study, the team looked at global datasets of NO2 concentrations, pediatric population distributions and asthma incidence rates proven related to traffic-derived NO2 pollution.

Results showed that Shanghai, China recorded the highest number of asthma incidence linked to traffic pollution. Up to 48 percent of pediatric asthma in the country was found caused by NO2. 

Around 40 percent of asthma cases in Moscow, Russia, and Seoul, South Korea, were found with NO2 traces. 

In the U.S., Los Angeles, New York, Chicago, Las Vegas and Milwaukee were among the major cities with the highest percentage of pediatric asthma cases linked to polluted air.

Due to the large number of children being affected by air pollution, the researchers called on WHO to consider their findings to make updates in its Air Quality Guidelines. The team said nearly 92 percent of new pediatric asthma cases attributable to NO2 were found in areas that met the WHO guideline.

"That finding suggests that the WHO guideline for NO2 may need to be re-evaluated to make sure it is sufficiently protective of children's health," Pattanun Achakulwisut, lead author of the paper and a postdoctoral scientist at Milken Institute SPH, said in a statement posted Wednesday on EurekAlert. 

"Our findings suggest that millions of new cases of pediatric asthma could be prevented in cities around the world by reducing air pollution," Susan Anenberg, senior author of the study and an associate professor of environmental and occupational health at Milken Institute SPH, said.