What is Particulate Matter?

Basic Information

In addition to monitoring ground-level ozone levels in West Michigan, the West Michigan Clean Air Coalition educates citizens about additional air quality concerns in our area, including particulate matter.
Particle matter pollution (PM) is the term for a mixture of solid particles and liquid droplets found in the air. Some particles, such as dust, dirt, soot, or smoke, are large or dark enough to be seen with the naked eye. Others are so small, they can only be detected using an electron microscope.

Particle pollution includes "inhalable coarse particles," with diameters larger than 2.5 micrometers and smaller than 10 micrometers and "fine particles," with diameters that are 2.5 micrometers and smaller. A single hair from your head is about 70 micrometers in diameter—which means a hair is 30 times larger than the largest fine particle.

These particles come in many sizes and shapes and can be made up of hundreds of different chemicals. 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.

The EPA regulates inhalable particles (fine and coarse). Particles larger than 10 micrometers (sand and large dust) are not regulated by EPA, and this is why the forecasts provided by the WMCAC (through the Michigan Department of Environmental Quality) only include fine particulate matter (PM2.5) at this time. Please keep in mind that if you have signed up for EnviroFlash you may receive email alerts regarding particulate matter. Currently, however, Ozone Action days are only called when ground level ozone is forecast to be unhealthy for sensitive groups. Ozone Action days are not called for unhealthy levels of particulate matter. For more information on EPA particulate matter standards click here.

What negative effects are associated with particulate matter pollution?

Health Effects
Particle pollution contains microscopic solids or liquid droplets that are so small that they can get deep into the lungs and cause serious health problems. The size of particles is directly linked to their potential for causing health problems. Small particles less than 10 micrometers in diameter pose the greatest problems, because they can get deep into your lungs, and some may even get into your bloodstream.

Numerous scientific studies have linked particle pollution exposure to a variety of problems, including:

increased respiratory symptoms, such as irritation of the airways, coughing, or difficulty breathing;
decreased lung function;
aggravated asthma;
development of chronic bronchitis;
irregular heartbeat;
nonfatal heart attacks; and
premature death in people with heart or lung disease.

People with heart or lung diseases, children and older adults are the most likely to be affected by particle pollution exposure. However, even if you are healthy, you may experience temporary symptoms from exposure to elevated levels of particle pollution.

Environmental Effects

Visibility reduction
Fine particles (PM2.5) are the major cause of reduced visibility (haze) in parts of the United States, including many of our treasured national parks and wilderness areas.

Environmental damage
Particles can be carried over long distances by wind and then settle on ground or water. The effects of this settling include: making lakes and streams acidic; changing the nutrient balance in coastal waters and large river basins; depleting the nutrients in soil; damaging sensitive forests and farm crops; and affecting the diversity of ecosystems.

Aesthetic damage
Particle pollution can stain and damage stone and other materials, including culturally important objects such as statues and monuments.

Further Reading

Particle Pollution and Your Health: Learn who is at risk from exposure to particle pollution, what health effects you may experience as a result of particle exposure, and simple measures you can take to reduce your risk. (PDF, 2 pp, 320 KB)

How Smoke From Fires Can Affect Your Health: It's important to limit your exposure to smoke -- especially if you may be susceptible. This publication provides steps you can take to protect your health.

Programs and Requirements for Reducing Particle Pollution

The Clean Air Act requires EPA to set National Ambient Air Quality Standards (NAAQS) for six criteria pollutants, of which particulate matter pollution is one. EPA works with partners at state, local, and tribal air quality agencies to meet these standards. In Michigan they primarily work through the Michigan Department of Environmental Quality (MDEQ).

Under the Clean Air Act (CAA), as amended in 1990, each state must develop a plan describing how it will attain and maintain the NAAQS. In other words, how it plans to clean up polluted areas and keep them clean. This plan is called the State Implementation Plan (SIP) and is required under Section 110 of the CAA (40 CFR Part 51, Subparts F & G). In general, the SIP is a collection of programs, including:

a monitoring program, which is a collection of monitoring devices which provide actual measurements of the concentrations in the air, to identify whether an area is meeting the air quality standards
air quality calculations and computer modeling, which are used to predict future trends and the effects of emissions reduction strategies
emissions inventories, which describe the sources and categories of emissions to the air for a given pollutant, and how much is emitted by each source or source category

There are four monitors in West Michigan that collect information for the MDEQ and EPA regarding particulate matter pollution. For a map of these monitoring stations click here.

More information

Realtime PM Data – view current particle pollution information from DEQ air monitoring sites.

PM Air Quality Standards (NAAQS) – find out what air quality levels are used to define "clean air" for particles under the Federal Clean Air Act

Particulate Matter Designations – find out if a geographic area you are interested in meets clean air standards for particle pollution

Regulatory Actions – find EPA regulations detailing the requirements for State Implementation plans for particle pollution, and fact sheets and summaries of those regulations

Controlling Particle Pollution – find information, and links to information, on work that is underway to reduce particles in the air, both by reducing directly emitted particles, and by reducing emissions of pollutants that are gases when emitted, but which form particles in the atmosphere.

Sources

The West Michigan Clean Air Coalition is a partnership of businesses, academic institutions, government agencies, industry, and non-profit organizations in Kent, Ottawa, Muskegon, and Kalamazoo counties working together to achieve cleaner air in the region through the education and promotion of voluntary emission reduction activities.