Green Heart Initiative
- Health Research
- Sensitive Groups
- Sources of Air Pollution
- Control and Reduce Air Pollution
- Innovative Technologies
For more than 40 years, EPA scientists have studied the health effects, sources and risks of air pollutants in support of the Clean Air Act. Six major air pollutants are now regulated by the EPA to protect public health and the environment. The research by EPA and others provided the foundation for the development of the nation’s air quality standards.
Air pollution is known to cause a variety of health problems. A more recent focus of research has been on the cardiovascular system, comprised of the heart and arteries. Key developments are listed below.
- Because ozone is such a widespread urban pollutant and clear impacts could be observed at typical daily exposure levels, the pollutant was studied in detail. Studies by EPA and others found effects on the respiratory system that led to refined outdoor air quality standards.
- In the mid-90s, research focused on fine particle pollution or PM2.5, and its impact on respiratory health.
- Studies by researchers at EPA and EPA-funded PM Research Centers at universities linked exposure to PM2.5 to cardiovascular effects, an unanticipated outcome.
- Epidemiology studies began to show that exposure to ozone, once thought to be just a respiratory problem, may also be linked to cardiovascular effects
- EPA researchers began to investigate ozone exposure in animal and human studies, finding that ozone, like PM2.5, can lead to heart problems
- EPA researchers have found that ozone is linked to changes in the cardiac and vascular systems in healthy young adults, specifically inflammation of the vascular system, heart rate variability, and conditions that prevents blood clots from dissolving. Animal studies by EPA provided similar findings.
- Research is being conducted on other air pollutants to determine what sources of pollutants, what mixtures and what level of exposure can result in health effects, including effects on the cardiovascular system.
Researchers are studying pollutants such as ozone and PM and mixtures in order to determine the health effects on the heart.
- Since we are often exposed to more than one air pollutant at a time, EPA scientists are studying mixtures of air pollutants and 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.
- EPA scientists are studying groups of people who 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, as well as healthy people, scientists are identifying risk factors and genes that may cause a person to be more sensitive to air pollution.
- EPA is using the Multi-Ethnic Study of Atherosclerosis (MESA) Air Pollution Study to examine the development and progression of atherosclerosis, also known as hardening of the arteries, and other health effects of long-term exposure to fine particles in different cities and ethnic groups.
- EPA’s Clean Air Research Centers (CLARCs) are studying various health effects including cardiovascular risks from exposure to air pollutants. The centers are focused on mixtures of pollutants rather than any single pollutant.
- With partial funding by EPA, the Health Effects Institute (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.
Air pollution may pose risks for heart health, especially for people with conditions that make them more sensitive to pollutants in the air. EPA is studying groups and individuals who may be more at risk of exposure to air pollutants.
- Genetic characteristics may be a risk factor for health problems from air pollution exposure. EPA is studying people with heart disease and looking at their exposure to sources of pollutants and the potential that their genetic makeup affected their response to pollutants and the development of their heart disease.
- EPA is conducting studies to examine the correlation between an increased risk of heart disease and cardiac episodes and pre-existing respiratory and cardiac conditions, underlying hypertension, diabetes, and obesity.
- Findings from the MESA Air Study on arteriosclerosis will contribute to an understanding of the different genetic makeup of ethnicities and susceptibility to air pollution.
Sources of Air Pollution
In order to understand the impacts of air pollution on the heart and cardiovascular system, researchers are studying sources. 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 evaluate the toxicity of air pollution mixtures and their related health effects.
- To better understand the impact of major community sources, EPA is assessing the exposure levels near sources such as ports and rail yards, roadways, and wildfires.
- Hospital and population data is being analyzed for impacts on specific low-income communities affected by a recent North Carolina wildfire with a focus on assessing whether the smoke increased emergency department utilization and hospital admissions for respiratory and heart problems.
Control and 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.
- Interventions can be done on an individual basis as well. One EPA study found that a diet rich in omega-3 fatty acids found in fish oil and other foods can protect against the risks of heart dysfunction from exposure to air pollution.
- EPA is developing the National Atlas for Sustainability, a web-based mapping tool that allows communities to estimate the potential benefits and costs of decisions related to community planning and development. Community leaders can assess air quality levels and their health impacts from different planning scenarios to reduce exposure to pollutants and increase respiratory and heart health.
- Scientists are developing a virtual cardiopulmonary system to replace the use of laboratory animals and clinical studies in determining the health effects of air pollution. Similar to other virtual computer models like the Virtual Liver and the Virtual Embryo, to model toxic effects, the virtual cardiopulmonary system will be used to predict the impacts of air pollutants on the airways, lungs, and heart.
- Using advanced computer technology, EPA is assessing the hazards and risks of chemicals to determine which are most likely to lead to adverse health effects. Using advanced scientific tools, scientists can screen thousands of chemicals in less time with less cost. The approach is to characterize mixtures and group them according to how they might affect the body.