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Healthy Heart Toolkit and Research: Current Research

Image of the Heart

Air pollution is known to cause a variety of health problems, including effects on the heart, nervous, and vascular system. A significant body of research has shown that long-term exposure to fine particulate matter, known as PM2.5, can impact heart disease. These particles can adversely affect the heart if it is weakened by disease.

Air pollution particles are emitted year-round from motor vehicles, power plants, industries, and forest fires and are created when sunlight interacts with vapor and gaseous pollutants. Evidence is also mounting that other air pollutants may affect the heart alone or in concert with particulate matter.

Research continues to focus on the relationship between air pollutants such as PM2.5, ozone and pollutant mixtures, and long-term and short-term effects on the cardiovascular system. The discoveries provide the scientific foundation to review the National Ambient Air Quality Standards and protect the health of the American people.

Health Effects

Researchers are studying air pollutants like ozone, PM, and mixtures to further understand the impacts on the heart and blood vessels and the potential impacts on underlying conditions, including hypertension, diabetes, and obesity.

  • CATHGEN. Using the CATHGEN database developed by Duke University School of Medicine researchers, EPA is exploring how health factors in individuals affect responses to air pollution. The research investigates the acute and chronic health effects of pollutant mixtures as well as individual effects on the cardiovascular system.

    Duke University’s CATHGEN web page Exit
  • Multi-pollutants. Since we are often exposed to more than one air pollutant at a time, air pollutant mixtures are being studied in human populations and in experimental animals to determine how they may interact with one another to cause health effects. Scientists are also studying selected mixtures where the effect of one pollutant may be modified by one or more in combination.
  • Vulnerable people. Some groups of people may be more susceptible to the negative effects of air pollution, including those with heart disease. Through close examination of at-risk groups— such as asthmatics, elderly people, or others with genetic markers for disease—as well as healthy people, scientists are identifying risk factors and genes that may cause a person to be more sensitive to air pollution.
  • Atherosclerosis. An EPA-funded study called the Multi-Ethnic Study of Atherosclerosis (MESA) Air Pollution Study examined the development and progression of atherosclerosis, also known as hardening of the arteries, and other health effects of long-term exposure to fine particles and multi-pollutants in different cities and ethnic groups.

    University of Washington grantee web page Exit

    EPA MESA web page
  • Air, Climate and Energy (ACE) Centers. EPA awarded grants to create research centers at three universities to investigate the effects of global climate change, technology, and societal choices on local and regional air quality and health. These university research centers will provide sound science to policymakers at the state and local levels for developing strategies that reduce health and environmental impacts of air pollution. Air, Climate and Energy Centers
  • Health Effects Institute (HEI). With partial funding by EPA, HEI is conducting research and assembling reports on exposure to mixtures of pollutants and very small particles, called ultrafine particles. Using models, researchers are working to analyze the health effects of these mixtures, including cardiovascular problems.

    Health Effects Institute Research

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Sources of air pollution

In order to understand the impacts of air pollution on the heart and cardiovascular system, researchers are studying combustion sources that emit particles and their precursors. Air pollution comes from a variety of natural and man-made sources, including wildfires, power plants, industry, and motor vehicles.

  • Using recent advances in molecular biology, researchers are working to determine the health risks to certain groups of people. Real-time monitoring is used to assess linkages between exposures to air pollution mixtures and their related health effects.
  • To better understand the impact of major emission sources near communities, EPA is assessing the pollutant exposure levels near known air pollution sources such as ports and rail yards, roadways, and wildfires.
  • Wildfire research is providing important information on the toxic effects of smoke exposure by individuals living near wildfires, including people in lower socioeconomic groups. Findings of a peat bog fire in North Carolina in 2008 show smoke from wildfires increases emergency room use because of lung and heart problems. Studies in experimental animals are being used to assess how different types of wildfires can carry varied risk of health effects due to varied emission components.

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Intervention strategies to control, reduce air pollution

EPA is evaluating tools and methods to help communities, states, and policy makers control and reduce air pollution’s health risks, including those to the heart.

  • Scientists are studying intervention strategies such as roadway barriers (walls or tree lines) to minimize pollutant exposure and health risks of roadway-related air pollutants.
  • Various modeling approaches that incorporate social and economic factors are being developed to assist communities with urban development and land use planning.
  • Potential personal intervention strategies are also being investigated. One EPA study found that dietary additions of omega-3 fatty acids, found in fish, can reduce some biochemical and physiological responses after exposure to air pollution.

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