Date: December 16, 2025
To: Lee M. Zeldin, Administrator
U.S. Environmental Protection Agency
1200 Pennsylvania Avenue, N.W.
Washington, DC 20460
Dear Administrator Zeldin:
We, the undersigned 105 groups and organizations, and on behalf of our millions of members and supporters nationwide, are gravely concerned by the Environmental Protection Agency (EPA)’s recent action abandoning its defense of national health-protective pollution standards for fine particulate matter (PM2.5 or soot). The national ambient air quality standard (NAAQS) for soot was strengthened in 2024 in line with scientific, health-based evidence; consensus among experts that the existing standards were insufficiently protective; and the EPA’s statutory requirement to promulgate NAAQS that protect human health with a margin of safety. You have not at all disputed the overwhelming scientific evidence supporting the NAAQS. In seeking to undo the soot standard and allow more pollution into our air and lungs, your EPA is undermining its own authority, skirting its responsibility to the American people, and sacrificing public health and safety and the very lives of vulnerable Americans to polluters’ interests.
Soot pollution is dangerous and can be deadly. Studies indicate that soot causes between 85,000-200,000 deaths every year in the United States.1 It is linked to a wide range of health challenges, including increases in hospitalization rates and emergency room visits, cases of asthma, heart attacks, strokes, heart disease, lung cancer, breast cancer, chronic obstructive pulmonary disease, Parkinson’s disease, dementia, low birth weight, preterm birth, and infant mortality.2,3
Air pollution is a nationwide problem, but the harms are experienced disproportionately across communities and populations. Research shows that the health harms of air pollution affect communities of color and low-income groups to a greater extent,4 with black communities exposed to roughly 1.5 times more deadly soot pollution than white communities.5 Children are also disproportionately impacted by soot pollution: their lungs and organ systems are still developing, and childhood exposure to unhealthy air can lead to lifelong health consequences.6
Soot is also the primary cause of reduced visibility, or haze, in urban, rural and wilderness areas as well as national parks.7 Haze that ruins scenic views is one of the most visible manifestations of this air pollution, while fine particles can also enter aquatic ecosystems and negatively affect the health of wildlife both directly and indirectly through bioaccumulation. The strengthened PM2.5 standard was a step in the right direction to achieving secondary benefits for the environment by reducing public welfare harms from this pollution.
Setting and implementing pollution standards to protect public health and the environment is fundamental to EPA’s mission. And seeking to weaken soot protections does not serve to achieve that mission or benefit the nation or our economic security. Cleaner air goes hand-in-hand with positive economic outcomes.8 Since 1970, as air pollution has gone down, economic growth has gone up.9 Decades of evidence show that we can both cut pollution and create jobs. We can protect children, families, workers, and natural spaces while growing the economy. We can reduce health harms and be a global leader in innovation.
The EPA is required by the Clean Air Act to set health-based NAAQS for criteria pollutants including PM2.5. As reaffirmed by a unanimous Supreme Court decision, NAAQS for PM2.5 must protect public health with an adequate margin of safety.10 The EPA’s own independent panel of experts unanimously recommended a stronger standard in order to achieve that requirement.11 EPA’s abandonment of its defense of the 2024 standard means it aims to revert back to an insufficient level of protection, allowing, by the agency’s own estimation, 4,500 more deaths annually, 290,000 lost work days, nearly 1 million more cases of asthma-related health complications, and up to $46 billion in unrealized public health benefits by 2032.12
Families, workers, and communities across America would benefit from EPA implementing the 2024 soot standard. And that is precisely what the EPA should and must be doing now. A major step in implementing the 2024 PM2.5 NAAQS is coming up in February 2026: formally identifying the areas that have unhealthily polluted air so states and Tribes with those areas in their jurisdiction can get to work developing pollution reduction strategies in line with the Clean Air Act’s commonsense track to healthy air.
Under your leadership and President Trump’s direction, the EPA has abandoned not only its defense of life-saving national pollution standards, but also its protection of families and workers against the health, economic, and environmental harms of dangerous soot pollution. Instead of taking steps to consign millions of Americans to still more years of breathing in polluted air that can cause illness or death, EPA should be focusing its energies and efforts on cleaning up the air. We urge the EPA to realign itself to its core mission and recommit itself to taking action that would truly protect human health and the environment.
Sincerely,
350 Bay Area Action
350 Colorado
5 Gyres Institute
AFGE Local 704
Air Alliance Houston
Alliance of Nurses for Healthy Environments
American Public Health Association
Animals Are Sentient Beings, Inc.
Appalachian Voices
Arizona Forward
Arizona Interfaith Power & Light
Asthma and Allergy Foundation of America
Between the Waters
Breathe Free Detroit
Breathe Project
California Communities Against Toxics
Californians Against Waste
Center for Biological Diversity
Center for Earth Energy & Democracy (CEED)
Center for Engagement Environmental Justice and Health
Center for Progressive Reform
Change the Chamber
Cherokee Concerned Citizens
Chesapeake Physicians for Social Responsibility
Citizens For Chiquita Canyon Closure
Clean Air Council
Clean Water and Air Matter
Climate Action California
Climate Action Campaign
Climate Communications Coalition
Climate Law & Policy Project
Coalition for Clean Air
Comite Pro Uno
Defend Our Health
Deignan Institute for Earth and Spirit at Iona University
Don't Waste Arizona
Earth Ethics, Inc.
Earthjustice
EcoMadres
EDF Action
Elders Climate Action
Elders Climate Action Maryland
Elders Coalition for Climate Action
Environmental Justice Ministry Cedar Lane Unitarian Universalist Congregation
Environmental Law & Policy Center
Environmental Protection Network
Faith Organizing Alliance
FreshWater Accountability Project
GAIA (Global Alliance for Incinerator Alternatives)
Girl Plus Environment
Great Lakes Business Network
GreenLatinos
Greenpeace USA
Group Against Smog & Pollution
Heartwood
Illinois Environmental Council
League of Conservation Voters
Little Village Environmental Justice Organization
Maryland League of Conservation Voters
Maryland Legislative Coalition
Maryland Legislative Coalition - Climate Justice Wing
Metropolitan Group
Micah Six Eight Mission
Michigan Clinicians for Climate Action
Moms Clean Air Force
Mothers & Others For Clean Air
Mount Shasta Bioregional Ecology Center
Nassau Hiking & Outdoor Club
National Environmental Health Association
National Parks Conservation Association
Natural Resources Defense Council
New Mexico Environmental Law Center
New Virginia Majority
New York Progressive Action Network
Nia Impact Capital
Northeastern Minnesotans for Wilderness
Nuclear Information and Resource Service ("for a nuclear-free, carbon-free world")
Ocean Conservation Research
Oil and Gas Action Network
Partnership for Policy Integrity
Physicians for Social Responsibility
Physicians for Social Responsibility of PA
Protect Our Streams
Putnam Progressives
Rachel Carson Council
Respiratory Health Association
Seneca Lake Guardian
Sethi Orchid Miner LLP
Sierra Club
Silvix Resources
Solar United Neighbors
Swan View Coalition, Inc.
The New York League Of Conservation Voters ‘NYLCV’
The Ocean Project
The People's Justice Council
Turtle Island Restoration Network
Union of Concerned Scientists
Valley Improvement Projects (VIP)
Valley Watch, Inc.
Vfp#35
Warehouse Workers for Justice
Washington Conservation Action
West Berkeley Alliance for Clean Air and Safe Jobs
Wheelbarrow Productions, Inc.
Zero Waste Ithaca
1. Science Advances, “PM2.5 polluters disproportionately and systemically affect people of color in the United States”
2. American Lung Association, State of the Air 2025
3. American Journal of Public Health, “Air Pollutants and Breast Cancer Risk: A Parallel Analysis of Five Large US Prospective Cohorts,” (Nov. 12, 2025)
4. Harvard School of Public Health, “Racial, ethnic minorities and low-income groups in U.S. exposed to higher levels of air pollution,” (Jan. 12, 2022)
5. American Journal of Public Health, “Disparities in Distribution of Particulate Matter Emission Sources by Race and Poverty Status,” (March 7, 2018)
6. Moms Clean Air Force, Fact Sheet: Soot Pollution and Your Health
7. National Parks Conservation Association, Air & Climate Report: Polluted Parks
8. EPA, “The Clean Air Act and the Economy”
9. EPA, “Benefits and Costs of the Clean Air Act”
10. Whitman v. Am. Trucking Ass’ns, 531 U.S. 457, 462-71 (2001).
11. CASAC Review of the EPA’s Policy Assessment for the Reconsideration of the National Ambient Air Quality Standards for Particulate Matter (External Review Draft – October 2021)
12. EPA, Final Rule to Strengthen the National Air Quality Health Standard for Particulate Matter: Health Sheet 1 (Feb. 7, 2024)