Air Pollution - Particulate Matter Brochure

This page last reviewed May 6, 2009

What is Particulate Matter (PM10)?

Particulate matter (PM10) pollution consists of very small liquid and solid particles floating in the air. Of greatest concern to public health are the particles small enough to be inhaled into the deepest parts of the lung. These particles are less than 10 microns in diameter - about 1/7th the thickness of the a human hair - and are known as PM10. This includes fine particulate matter known as PM2.5.

PM10 is a major component of air pollution that threatens both our health and our environment.

Where does PM10 come from?

In the western United States, there are sources of PM10 in both urban and rural are as, major sources include:

  1. Motor vehicles.
  2. Wood burning stoves and fireplaces.
  3. Dust from construction, landfills, and agriculture.
  4. Wildfires and brush/waste burning.
  5. Industrial sources.
  6. Windblown dust from open lands.

PM10 is a mixture of materials that can include smoke, soot, dust, salt, acids, and metals. Particulate matter also forms when gases emitted from motor vehicles and industry undergo chemical reactions in the atmosphere.

How does PM10 affect our health?

PM10 is among the most harmful of all air pollutants. When inhaled these particles evade the respiratory system's natural defenses and lodge deep in the lungs.

Health problems begin as the body reacts to these foreign particles. PM10 can increase the number and severity of asthma attacks, cause or aggravate bronchitis and other lung diseases, and reduce the body's ability to fight infections.

Although particulate matter can cause health problems for everyone, certain people are especially vulnerable to PM10's adverse health effects. These "sensitive populations" include children, the elderly, exercising adults, and those suffering from asthma or bronchitis.

Of greatest concern are recent studies that link PM10 exposure to the premature death of people who already have heart and lung disease, especially the elderly.

Does PM10 affect our view?

PM10 is often responsible for much of the haze that we think of as smog. This is a problem in our cities, rural areas and pristine areas - such as national parks and forests.

What is being done to reduce PM10 pollution?

The United States Environmental Protection Agency has set air quality standards for PM10. Based on health research, these identify acceptable levels of PM10. Currently, these standards are violated in many parts of the western United States.

Air quality agencies in several states have developed, or are now developing, air quality plans to bring PM10 concentrations down to healthful levels. These plans include a variety of programs to reduce emissions, including:

  1. Dust control for roads, construction, and landfills.
  2. Landscaping, barrier, and fencing to reduce windblown dust.
  3. Programs to reduce emission from wood stoves and fireplaces.
  4. Cleaner - burning gasoline and diesel fuels.
  5. Emission control devices for motor vehicles.
  6. Controls for industrial facilities.

What can you do?

Here are a few things individuals, business, and other organizations can do immediately to reduce the threat of PM10:

  1. Reduce travel on days with poor air quality.
  2. Avoid vigorous physical activity on days that have poor air quality.
  3. Avoid using your wood stove and fireplace on days that have poor air quality.
  4. Avoid using leaf blowers and other dust - producing equipment.
  5. Drive slowly on unpaved roads and other dirt surfaces.
  6. Get involved with air quality improvement programs in your community.
  7. If you own or operate an industrial source of PM10, comply with local rules that apply to your operation. Work with local agencies to develop strategies that will further reduce PM10 emissions.