Environmental Services Program

Particulate Matter

What is Particulate Matter (PM)?

Particulate Matter (PM) is a type of air pollution made up of tiny solid particles and liquid droplets suspended in the air. These particles can vary in size, composition, and origin, and are categorized by their diameter:

• PM₁₀ (Coarse): Particles with a diameter of 10 micrometers or smaller, such as dust, pollen, and mold.
• PM₂.₅ (Fine): Particles with a diameter of 2.5 micrometers or smaller, often created by combustion processes like vehicle engines, wood burning, or industrial emissions.

Figure 1: Size Comparisons for PM Particles
Source: Retrieved from What is PM, and how does it get into the air?, U.S. EPA, www.epa.gov/pm-pollution/particulate-matter-pm-basics

Because these particles are so small — especially PM₂.₅ — they can be inhaled deep into the lungs and even enter the bloodstream, posing serious health risks.

Where Does Particulate Matter Come From?

Particulate Matter pollution comes from both natural and human-made sources. Some common sources include:

• Vehicle exhaust and diesel engines
• Wood stoves and campfires
• Industrial processes and power plants
• Construction and road dust
• Agricultural activities
• Wildfires
• Windblown dust and pollen

While larger particles often settle to the ground quickly, smaller particles like PM₂.₅ can stay suspended in the air for long periods and travel long distances. This means even remote and rural areas like the LTBB community can experience elevated PM levels, especially during regional wildfires or dust events.

When is PM Pollution a Problem?

PM pollution can occur year-round, but certain conditions can make it worse:

• Cold winter months (due to wood burning and temperature inversions trapping pollution close to the ground)
• Summer wildfires (which produce large amounts of fine particles)
• Dry, windy conditions that stir up dust
• Busy travel times or areas with heavy traffic

Health Effects of Particulate Matter

Exposure to PM pollution can have both short-term and long-term health effects, particularly for sensitive groups like children, elders, and people with heart or lung conditions such as asthma or COPD. Health effects of PM exposure include:

• Difficulty breathing, coughing, and throat irritation
• Aggravation of asthma and bronchitis
• Increased risk of heart attacks and strokes
• Premature death in people with pre-existing heart or lung disease

For LTBB community members, PM pollution can make it difficult to safely engage in important outdoor activities like fishing, hunting, ceremonies, and gathering traditional medicines. Poor air quality days may limit time spent outdoors or near wood fires — both important aspects of Odawa cultural practices.

Figure 2: Fine Particulate Matter (PM2.5) Infographic
Source: Retrieved from What are the Health Effects of PM?, Capital Area Council of Governments – Air Central Texas, https://aircentraltexas.org/en/regional-air-quality/what-is-particulate-matter

Environmental Effects of PM on LTBB Lands

Particulate Matter pollution doesn’t just affect people — it can also impact the environment and natural resources important to the LTBB community. Environmental effects include:

• Reduced visibility (haze) over natural landscapes, affecting scenic views and tourism
• Deposition of particles onto soil and water, potentially harming fish and wildlife
• Damage to plants and trees by clogging leaf pores, reducing growth and photosynthesis
• Increased stress on culturally significant species of flora and fauna

PM pollution can also settle on lakes, rivers, and streams, potentially impacting water quality and aquatic life important for subsistence fishing and ecosystem health.

What Can Be Done to Reduce Particulate Matter Pollution?

Efforts to reduce PM pollution involve both community action and policy enforcement. The U.S. Environmental Protection Agency (EPA) sets national standards for PM levels, and states and Tribes like LTBB implement programs to monitor and improve local air quality. LTBB’s Environmental Services Program (ESP) works to protect Tribal sovereignty and public health through air quality research and outreach.

Community members can help reduce PM pollution by:

• Limiting wood burning or using cleaner-burning stoves
• Driving less or combining trips to reduce vehicle emissions
• Avoiding outdoor burning of trash or yard waste
• Keeping vehicles and equipment well-maintained
• Checking local air quality forecasts before outdoor activities

Figure 3: WHO PM2.5 Health Recommended Guidelines  
Source: Retrieved from IQAir, https://cms.iqair.com/sites/default/files/inline-images/2236_WHO-Guidlines-Chart_06152022.jpg

When air quality is poor — especially during wildfire smoke events — community members should take steps to protect their health by:

• Staying indoors when possible
• Using air purifiers or creating clean air spaces
• Wearing N95 masks outdoors if necessary
• Monitoring air quality at AirNow.gov or the AirNow App

APA References List

2024 World Air Quality Report. IQAir. (n.d.). https://www.iqair.com/world-air-quality-report

AirNow.gov. (n.d.). Air quality index (AQI). Retrieved from https://www.airnow.gov

American Lung Association. (n.d.). What is particulate matter? Retrieved from https://www.lung.org/clean-air/outdoor/what-makes-air-polluted/particle-pollution

Centers for Disease Control and Prevention. (2020). Health effects of particulate matter. Retrieved from https://www.cdc.gov/air/particulate_matter.html

Environmental Protection Agency. (n.d.). Particulate matter (PM) pollution. Retrieved from https://www.epa.gov/pm-pollution

Environmental Protection Agency. (2024a). What is PM, and how does it get into the air?. EPA. https://www.epa.gov/pm-pollution/particulate-matter-pm-basics

Governments, C. A. C. of. (n.d.). What is particulate matter?. English. https://aircentraltexas.org/en/regional-air-quality/what-is-particulate-matter

World Health Organization. (n.d.). Ambient (outdoor) air quality and health. Retrieved from https://www.who.int/news-room/fact-sheets/detail/ambient-(outdoor)-air-quality-and-health