Traffic Pollution Raises ER Visits for Asthma
Study Shows Link Between Kids' Trips to ER and High Pollution Levels From Traffic Sources
WebMD News Archive
April 22, 2010 -- Ozone and pollution emitted by traffic have been linked to
spikes in asthma-related emergency room visits among children, particularly
during summer, according to a large, population-based study.
Researchers from the Rollins School of Public Health at Emory University in
Atlanta collected data on more than 91,000 emergency room visits that took
place at 41 Atlanta-area hospitals between 1993 and 2004. The children, who
ranged from ages 5 to 17, had been seen in a hospital emergency room for asthma
The research team also gathered data from the Study of Particles and Health
in Atlanta to assess daily air quality and the presence of 10 different
pollutants from traffic sources and ground-level ozone, a form of oxygen that
is created when organic compounds, like fossil fuels, mix with nitrogen oxide
The study showed that ozone was strongly associated with an increase in
pediatric emergency room visits due to asthma, especially between the months of
May and October. There was also evidence of a dose-response relationship,
meaning the greater the ozone exposure, the greater the likelihood of an
asthma-related emergency room visit. This association was observed beginning
with concentrations as low as 30 parts per billion.
When analyzing all of the pollutants together, the researchers found that
ozone and primary pollutants from traffic were independently associated with
pediatric asthma hospitalizations.
The researchers also reported that emergency room visits for pediatric
asthma increased by 60% during the colder months, a factor that is not
surprising given that viral respiratory infections occur more frequently during
the winter and can worsen asthma. However, the association between pollution
and increased emergency room visits held even after taking seasonal differences
Pollution's Impact on Public Health
The findings were released just in time for Earth Day, a worldwide effort
commemorated on April 22 and created to rally communities and individuals
toward improving environmental standards. The study results were published on
the American Thoracic Society's web site ahead of the print edition of the
American Journal of Respiratory and Critical Care Medicine.
"Characterizing the associations between ambient air pollutants and
pediatric asthma exacerbations, particularly with respect to the chemical
composition of particulate matter, can help us better understand the impact of
these different components and can help to inform public health policy
decisions," writes study researcher Matthew J. Strickland, PhD, MPH, assistant
professor of environmental health.