How Mobile Source Pollution Affects Your Health

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Mobile sources of air pollution

Mobile sources of air pollution are divided into two categories:

On-road vehicles include:
  • Motorcycles;
  • Passenger cars and trucks; and
  • Commercial trucks and buses.
Nonroad vehicles and engines include: 
  • Aircraft;
  • Heavy equipment;
  • Locomotives;
  • Marine vessels;
  • Recreation vehicles (snowmobiles, all-terrain vehicles, etc.); and
  • Small engines and tools (lawnmowers, etc.).
Related documents:
Use the links below to visit EPA websites about mobile and stationary sources of air pollution, including factories, refineries, boilers, and power plants.

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Smog and Your Health

Ground level or "bad" ozone is not emitted directly into the air, but is created by chemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOC) in the presence of sunlight. Ozone at ground level is a harmful air pollutant, because of its effects on people and the environment, and it is the main ingredient in “smog." Breathing ozone can trigger a variety of health problems, particularly for children, the elderly, and people of all ages who have lung diseases such as asthma.

Breathing ozone can:
  • Make it more difficult to breathe deeply and vigorously;
  • Cause shortness of breath, and pain when taking a deep breath;
  • Cause coughing and sore or scratchy throat;
  • Inflame and damage the airways;
  • Aggravate lung diseases such as asthma, emphysema, and chronic bronchitis;
  • Increase the frequency of asthma attacks;
  • Make the lungs more susceptible to infection;
  • Continue to damage the lungs even when the symptoms have disappeared; and
  • Cause chronic obstructive pulmonary disease (COPD).
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Particle Pollution

Particle pollution (also called particulate matter or PM) is the term for a mixture of solid particles and liquid droplets found in the air. Some particles, known as primary particles are emitted directly from a source, such as construction sites, unpaved roads, fields, smokestacks or fires. Others form in complicated reactions in the atmosphere of chemicals such as sulfur dioxides and nitrogen oxides that are emitted from power plants, industries and automobiles. These particles, known as secondary particles, make up most of the fine particle pollution in the country.

Particulate Matter is associated with:
  • Premature death in people with heart or lung disease,
  • Nonfatal heart attacks,
  • Irregular heartbeat,
  • Aggravated asthma,
  • Decreased lung function, and
  • Increased respiratory symptoms, such as irritation of the airways, coughing or difficulty breathing;
  • Reduced visibility (haze) in many parts of the U.S., including many of our national parks and wilderness areas; and
  • Lake and stream acidification. 
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Near Roadway Air Pollution and Health 

People who live, work or attend school near major roads appear to have an increased incidence and severity of health problems associated with air pollution exposures related to roadway traffic. Children, older adults, people with preexisting cardiopulmonary disease, and people of low socioeconomic status are among those at higher risk for health impacts from air pollution near roadways.  

These risks include:
  • Higher rates of asthma onset and aggravation;  
  • Cardiovascular disease;  
  • Impaired lung development in children;  
  • Pre-term and low-birthweight infants;  
  • Childhood leukemia; and
  • Premature death. 
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Air Toxics

Air toxics tend to pose greater risks in urban areas because these areas have large populations and a higher concentration of emission sources, including stationary sources like power plants. Low-income neighborhoods, tribal populations and communities of color that live in urban areas may be disproportionately exposed to air pollution, which is a barrier to economic opportunity and security. 

People exposed to toxic air pollutants at sufficient concentrations and durations may have an increased chance of getting cancer or experiencing other serious health effects, including: 

  • Damage to the immune system;   
  • Neurological disorders;
  • Reproductive disorders (e.g., reduced fertility);
  • Developmental disorders; and
  • Respiratory and other health problems.  

In addition to exposure from breathing air toxics, some toxic air pollutants such as mercury can deposit onto soils or surface waters, where they are taken up by plants and ingested by animals and are eventually magnified up through the food chain. Like humans, animals may experience health problems if exposed to sufficient quantities of air toxics over time. 

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