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  2. Air Research

Research on Near Roadway and Other Near Source Air Pollution

On this page:

  • Overview
  • Roadways
  • Ports and Rail Yards
  • Wildfires
  • Related Resources

Overview

People who live and work near sources of air pollution can be exposed to higher levels of air contaminants, many of which contribute to adverse health effects including:
  • reduced lung function,
  • asthma,
  • cardiovascular disease, and
  • premature death.
Some communities are more impacted than others. Children, older adults, people with pre-existing cardiopulmonary disease, and people living in low socioeconomic communities are among those at higher risk for health impacts associated with living near:
  • busy highways,
  • rail yards,
  • marine ports, and
  • industries where pollutants are emitted from multiple sources.

Smoke from wildfires is another close-by source of air pollution that is becoming more common because of the impacts of a changing climate.  As a result, some populations who live in areas prone to wildfires are more vulnerable to the effects of wildfire smoke. Wildfires can become a regional air pollution concern as well since smoke can travel many miles to other locations.

Research is conducted to:

  • Assess near-source impacts for single source and complex multi-source environments.
  • Understand factors influencing adverse health effects attributed to near-source impacts.
  • Develop models and tools to quantify near-source emissions and exposures to guide community planning.
  • Develop mitigation strategies to reduce emissions, exposures and health effects.
The research includes field studies, computer modeling, analytical methods development, and epidemiological and toxicological studies to evaluate exposures and health effects of air pollutant emissions.

Findings provide important information to:

  • Develop and implement the National Ambient Air Quality Standards (NAAQS).
  • Develop emissions standards and control strategies.
  • Assist states, communities and local groups with planning for roads, schools, and other land-use decisions as well as regional wildfire smoke overdrafts.  

Roadways

With more than 45 million people in the U.S. living within 300 feet of a major transportation facility or infrastructure, notably busy roads, there is concern about the potential health impacts from air pollutants emitted from cars, trucks and other vehicles.  Research has demonstrated that exposure to pollutants emitted from motor vehicles can cause lung and heart problems and premature death.

EPA’s emissions and fuel standards have reduced pollutant emissions from on-road vehicles.  However, additional research is being conducted on alternative mitigation strategies to further reduce the impact of living near busy roads.  For example, researchers are evaluating how roadway design, including noise barriers and roadside vegetation, can help to reduce exposure to air pollutants.

  • Recommendations for Constructing Roadside Vegetation Barriers to Improve Near-Road Air Quality
  • Near Roadway Air Pollution and Health: Frequently Asked Questions

Researchers continue to study the health effects of single and multiple pollutants and examine specific components of emissions that are associated with the effects. In addition, EPA supports the Health Effects Institute, an independent nonprofit organization that provides science on the health effects of pollutants from motor vehicles and other sources. Supported jointly with industry, HEI has produced important research findings on the health effects of air pollutants related to motor vehicle emissions.

HEI Reports:

  • Research Report: Concentrations of Air Toxics in Motor Vehicle-Dominated Environments
  • Special Report: Traffic-Related Air Pollution: A Critical Review of the Literature on Emissions, Exposure, and Health Effects

Ports and Rail Yards

Ports and rail yards are another source of air pollution from locomotives, transport trucks, loading and unloading equipment, and ships. The many different types of traffic and activity at rail yards and ports generates a variety of pollutants that can impact nearby communities and neighborhoods. Research is conducted to better understand near-rail and near-port air emissions and air quality, including how pollutants from these sources impact areas surrounding these facilities and nearby freight movement corridors. Studies are examining the sources of emissions, how emissions are dispersed to surrounding areas, and ways to improve modeling to evaluate near-source impacts and control strategies.

Wildfires

Research has found that wildfire smoke can increase health risks and leads to lung and heart problems and premature death. Climate-related changes and land-use practices are expected to increase the risk of wildfires in the coming decades, pointing to a growing need for more information on the health and economic impacts.

Researchers continue to focus on understanding the health effects from wildfires, identify the most susceptible populations, learn more about the economic effects in terms of health care costs, lost revenues, and loss of environmental resources. Research is also pursuing ways to mitigate the health effects from wildfires.

Publications

Roadways & Air Research Publications

  • Journal articles about Roadways
  • Reports about Roadways

Ports & Air Research Publications

  • Panama Canal Expansion Illustrates Need for Multimodal Near-Source Air Quality Assessment 
    • Other journal articles about Ports
  • Reports about Ports

Railyards & Air Research Publications

  • Journal articles about Railyards
  • Cicero Rail Yard Study (CIRYS) Final Report (PDF)(159 pp, 12 MB, About PDF)
    • Other reports about Railyards

Wildfires & Air Research Publications

  • Cardiopulmonary toxicity of peat wildfire particulate matter and the predictive utility of precision cut lung slices
    • Other journal articles about Wildfires
  • Reports about Wildfires

Related Resources

  • 2024 Science Matters Story: Sowing Seeds for Cleaner Air: How EPA Researchers are Addressing Air Pollution at Chicago Area Schools
  • 2020 Science Matters Story: Researchers Assess Roadside Vegetation Barriers with a Suite of Air Monitors
  • 2017 Science Matters Story: Living Close to Roadways: Health Concerns and Mitigation Strategies
  • Near-road NO2 Monitoring
  • Health Effects Institute
  • Smog, Soot, and Other Air Pollution from Transportation

Air Research

  • Air Monitoring & Emissions
  • Air Quality Modeling
  • Wildland Fires
  • Health Effects from Air Pollution
  • Air & Energy
  • Outreach, Tools & Resources
Contact Us About Air Research
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on February 14, 2025
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