A large body of research has been published in peer-reviewed journal articles by EPA and EPA-funded scientists on the link between air pollution and asthma. Highlights of recent discoveries show how research is improving our understanding of the contribution of air pollution to the health problem of asthma. 

Full list of asthma-related publications from EPA’s Science Inventory

Near-road air monitoring tool R-LINE

• EPA researchers have updated its dispersion model called R-LINE (v.1.2) to better capture temporal and spatial variability of mobile source-related concentrations in the near-road environment. The modeling system provides information on exposure to traffic-related air pollutants, and model outputs are matched to the desired temporal and spatial resolution needed for the health study.
• R-Line is available to the public and can be found on the Community Modeling & Analysis System Exit. The site is a forum for air quality modelers and others to use R-LINE and contribute to the improvement and future development of this model.

Children’s lung development and exposure to air pollution

• Lung function development in children with and without asthma improved with declines in air pollution from 1994-2011, according to a study by the University of Southern California. Researchers found that respiratory health in children improved as air pollution decreased over each four-year study period in southern California. The study is partially funded by the Health Effects Institute (HEI), an independent research organization funded by EPA and industry partners to investigate the health effects of air pollution.
• Association of Improved Air Quality with Lung Development in Children Exit, published in the New England Journal of Medicine, March 2015.

Size of particulate matter effect on asthma

• EPA researchers have found links between the size of particulate matter and its relationship to allergic asthma. Downwind coarse particulate matter increased inflammation indicators related to asthma more than upwind coarse PM. In contrast, upwind fine PM increased indicators related to inflammation more than the downwind fine PM. This finding supports previous research showing that source as well as size of PM contribute to PM health effects.
• Differential Effects of Particulate Matter Upwind and Downwind of an Urban Freeway in an Allergic Mouse Model Exit, published in Environmental Science and Technology, February 2015.

Ozone exposure and asthma in rural areas

• EPA researchers are working to improve the ability to conduct research on the health effects of air pollution in rural areas. Rural areas are difficult to study because of the limited data from regulatory air monitoring networks, which are located in metropolitan cities. Using the Community Multiscale Air Quality (CMAQ) model, researchers have studied associations between asthma emergency department visits and short term ozone exposure.
• The results support a link between short-term ozone exposures and asthma emergency department visits and suggest that children and individuals living in counties with poorer health status are at increased risk of asthma-related visits to the emergency department following ozone exposure.
• Influence of Urbanicity and County Characteristics on the Association between Ozone and Asthma Emergency Department Visits in North Carolina Exit, published in Environmental Health Perspectives, May 2014.