What Is Particle Pollution and Does It Affect Health?

It's often too small to see, but it can kill you

Particle pollution, also known as particulate matter, is a mixture of tiny particles and droplets made up of dirt, dust, soot, smoke, and liquid compounds. These particles are a type of air pollution, and they can be particularly damaging to your health.

This article explores the health risks of particle pollution and the types that are the most harmful. Plus, it includes things you can do to protect yourself.

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Health Risks of Particle Pollution

When you inhale particle pollution, it can harm your lungs, especially if you have lung diseases such as chronic obstructive pulmonary disease or asthma. Particle pollution also has been implicated in heart attacks and in lung cancer, and in low birth weight for babies. Exposure to this type of air pollution can lead to eye and throat irritation.

Particle pollution is typically made up of components like nitrates, sulfates, organic chemicals, metals, and soil or dust particles. The ingredients can vary by season. For example, soot and smoke from wood fires, more common in winter, is a form of particle pollution.

Early evidence suggests locations with a high amount of air pollution have higher death rates for COVID-19 patients, compared to locations with less air pollution, but more research is needed.

Which Particles Are More Harmful?

When it comes to particle pollution, the Environmental Protection Agency (EPA) says that the size of the particle matters most.

In general, smaller particles (those that are 10 micrometers or less in diameter) have a greater potential for causing health problems than larger ones. This is because smaller particles can enter the lungs much more easily during inhalation, by way of the nose and throat. Some even can enter your bloodstream.

The EPA separates particle pollution into two distinct categories:

  • Inhalable coarse particles often are found near dusty roadways or industrial areas, for example. They are larger than 2.5 micrometers and smaller than 10 micrometers in diameter. Sources of this size of particle pollution include grinding operations and dust stirred up by traffic on roads.
  • Fine particles are found in smoke and haze. They can be emitted from forest fires, or they can form when gasses from industrial power plants or cars reach the air and produce a chemical reaction.

It's estimated that reducing fine particle pollution by 10% could prevent more than 13,000 deaths annually in the U.S.

Protecting Yourself From Particle Pollution

It may seem like particle pollution is all around you (and it is), but there are some steps you can take to protect yourself from it.

First, familiarize yourself with the EPA's Air Quality Index, which is reported daily on weather websites (and on weather broadcasts, especially when it reaches unhealthy levels).

When you plan a day outdoors, check the Air Quality Index, and consider changing your plans to spend more time indoors if the air quality is expected to be problematic.

In addition, when air quality is bad or marginal, try not to plan outdoor activities that cause you to breathe heavily. In other words, walk leisurely instead of jogging, and avoid busy roads where there's more traffic (and therefore pollution).

Older adults, people with heart or lung conditions, and babies and children are the most susceptible to health problems from particle pollution, so take extra care to protect yourself and your family if you fall into those categories.


Particle pollution is made of many different components and tends to vary by season. Once inhaled, it can affect the lungs and heart.

Particles that are 10 micrometers or smaller in diameter can more easily pass into the lungs and are generally more of a health risk. 

The EPA's Air Quality Index can alert you to any air quality concerns in your area.

4 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. American Lung Association. Particle pollution.

  2. Harvard University. Exposure to air pollution and COVID-19 mortality in the United States.

  3. U.S. Environmental Protection Agency. Particle pollution and your patients' health.

  4. Centers for Disease Control and Prevention. Outdoor air.

By Deborah Leader, RN
 Deborah Leader RN, PHN, is a registered nurse and medical writer who focuses on COPD.