Fine Particle Pollution Will Soon Spawn a Stormcloud of News

June 8, 2022
Soot in a smoke cloud plume generated by extensive Pacific Northwest wildfires in summer 2017. Photo: NOAA Research News.

TipSheet: Fine Particle Pollution Will Soon Spawn a Stormcloud of News

By Joseph A. Davis

Soot will soon be in the news again, and environmental journalists should get ready to tell their audiences how it will affect them at the local and regional level.

The reason is that the U.S. Environmental Protection Agency is preparing a rulemaking on soot that may be proposed as soon as this summer.

No matter what the EPA proposes, there will be controversy. Actually, it has been controversial since the Clean Air Act was passed in 1970.


Why it matters

Soot is known to air pollution geeks as particulate matter. When the particles are 2.5 microns or smaller, it is called PM 2.5, or fine particulates. Inhaling PM 2.5 is bad for human health.

The problem with fine particulates is that their size allows them to go deep into the lungs. That makes them more damaging.

The health harms that PM 2.5 can cause or worsen only begin with lung diseases like bronchitis, asthma, lung cancer and COPD. They can also cause cardiac arrhythmias and heart attacks, especially in people with chronic heart disease.


Some research suggests that excess

deaths from PM 2.5 in the U.S. alone

amount to more than 50,000 per year.


Populations in underprivileged communities tend to be more exposed and face greater risks. Other vulnerable populations include the newborn, the elderly and people with chronic disease. Some research suggests that excess deaths from PM 2.5 in the U.S. alone amount to more than 50,000 per year.

The particles may vary a lot — they can consist of many different substances from many different sources.

Coal-burning power plants are still one source. Modern pollution control devices like baghouse filters and scrubbers can remove many of the particulates — but they are not always installed and working.

But wildfires, cars and trucks, factories and construction can also be major sources. Sometimes particles can also form from gases like sulfur dioxide emitted by power plants.


The backstory

The Clean Air Act requires the EPA to set (and revise) air pollution standards for health-harming pollutants. These are called the National Ambient Air Quality Standards, or NAAQS. Particulates (both fine particulates and the larger PM 10) are bad enough to require NAAQS.

The Clean Air Act requires regular review of the NAAQS and the science behind them, and the EPA has tightened the NAAQS for particulates over the years. There has been pushback from the start, not only from the electric utility industry, which back then burned a lot of coal, but from the petrochemical, manufacturing, agriculture, construction and other industries.

Because long-term exposure to particulates is even more harmful than short-term, the PM 2.5 standard evolved in two parts — an annual average and a 24-hour average. Over the years, the standards were progressively tightened.

Cutting to the chase: In December 2020, the EPA announced that it would keep the existing particulate air standards. You may notice that this was a month after Trump had lost the election and during the dying days of his administration. But the incoming Biden EPA, under Administrator Michael S. Regan, announced in June 2021 that it would reconsider this decision.

Since then, the EPA’s Clean Air Scientific Advisory Committee has urged the agency to tighten PM 2.5 standards. After that, it was news that the EPA air staff let it be known they opposed tightening the standard.


Story ideas

  • How bad is particulate air pollution in your region or locality? What is the trend?
  • Is your area in “attainment” of the PM 2.5 standard? Has it been so historically?
  • What are the major sources of particulate pollution in your area? Which sources have the worst health consequences? Talk to your state and local air agencies about this.
  • What actions (including enforcement) have state and local governments in your area taken to reduce or control particulate pollution?
  • Talk to staff at your local emergency rooms (while respecting their time constraints), or your local public health agency. How do emergency room visits (e.g., for asthma) correlate with times of high particulate pollution?
  • Does your area experience particulate pollution from wildfire? How about dust storms? What’s the health impact?


Reporting resources

  • AirNow: This site, a multi-agency collaboration with the EPA as a main player, will tell you what the current PM 2.5 pollution level is — in near-real-time — in your ZIP code.
  • EPA: You can find lots of info about PM 2.5 on the agency website.
  • State agencies: Under the Clean Air Act, enforcement in most states is delegated to the state’s environmental agency.
  • American Lung Association: A nonprofit organization that advocates for lung health.
  • Moms Clean Air Force: A nonprofit organization that advocates for clean air.

[Editor’s Note: For more on the politics of particulate air pollution, see TipSheets on the EPA soot standard and the Trump administration regulatory rollback, as well as a WatchDog Opinion on the EPA scientific integrity policy. For more on particulate sources, see TipSheets on wood-burning stoves and smoke from wildfires. To track data on particulates, check out Toolboxes on air quality monitors and on wildfire smoke, as well as this piece on the EPA’s environmental justice mapping tool. There’s also more about the Lung Association’s State of the Air report. Plus, read Inside Story Q&As on reporting local impacts of air pollution from a local coke plant and on kids sickened by air pollution, and a BookShelf review of “Choked: Life and Breath in the Age of Air Pollution.” For the latest headlines, see top “air” stories from EJToday.]

Joseph A. Davis is a freelance writer/editor in Washington, D.C. who has been writing about the environment since 1976. He writes SEJournal Online's TipSheet, Reporter's Toolbox and Issue Backgrounder, and curates SEJ's weekday news headlines service EJToday and @EJTodayNews. Davis also directs SEJ's Freedom of Information Project and writes the WatchDog opinion column.

* From the weekly news magazine SEJournal Online, Vol. 7, No. 23. Content from each new issue of SEJournal Online is available to the public via the SEJournal Online main page. Subscribe to the e-newsletter here. And see past issues of the SEJournal archived here.

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