Press Release Jun 10, 2021

EPA to Revisit Clean Air Standards, Prioritizing Science and Data

“We are pleased that the EPA is once again prioritizing science and its obligation to protect people and the environment." -  Ulla Reeves, NPCA's Clean Air Program Senior Advocacy Manager

Washington, DC — Today, the Environmental Protection Agency (EPA) announced it will reconsider the recent National Ambient Air Quality Standards (NAAQS) for particulate matter that were put in place during the last administration. In December 2020, despite scientific research demonstrating the incredibly damaging health and ecosystem harms from PM2.5 – soot spewed into the air by power plants and vehicles – the EPA announced it would keep the current, inadequate NAAQS in place instead of strengthening the standards.

These nationwide standards were originally created to protect both human health (primary standards) and our environment (secondary standard). The primary, health-based standards are meant to protect our most vulnerable populations like children, the elderly, people of color and people with preexisting health conditions. Research shows that exposure to PM2.5 is associated with thousands of premature deaths and can affect people’s lungs and heart and cause a variety of other health problems, including heart attacks, asthma and difficulty breathing.

The secondary, welfare-based standards are meant to safeguard our environment, including our national parks, wildlife, waters and climate. Yet, 85 percent of our national parks continue to have air that is unhealthy to breathe at times, while 88 percent have sensitive animal species and habitat that have been damaged by air pollution. PM2.5 can have a harmful effect on wildlife both big and small. Fish, frogs, snails and other aquatic life can absorb particulate matter, and as these animals are consumed by other predators, the particulate matter travels up the food chain to eagles, osprey, otters, pelicans and grizzly bears. Particle pollution can also travel hundreds of miles from its source dirtying the air in our national parks, and in turn impacting visitation that local economies depend on.

Represented by Earthjustice, NPCA and numerous partners sued EPA in January 2021.

Statement by Ulla Reeves, Clean Air Program Senior Advocacy Manager for the National Parks Conservation Association (NPCA):

“We are pleased that the EPA is once again prioritizing science and its obligation to protect people and the environment. Inadequate particulate matter standards on top of a global health pandemic has wreaked havoc on our most vulnerable communities, who are already disproportionately harmed by exposure to air pollution. We fully support EPA following the science to revisit and build back better standards.

“This is a great first step towards better protecting the health of our communities and ecosystems. People visit national parks expecting clean air and clear views, yet in reality, fine particulate matter leads to hazy skies and poor air quality in parks across the country from Cape Cod National Seashore to Yosemite. EPA must revise the secondary standards to follow the science and combat this pollution and the effects it is having on our country’s most treasured natural places and delicate ecosystems. We all deserve to breathe clean air and enjoy clear skies in our communities and national parks without being exposed to preventable pollution.”


About the National Parks Conservation Association: Since 1919, the nonpartisan National Parks Conservation Association has been the leading voice in safeguarding our national parks. NPCA and its nearly 1.6 million members and supporters work together to protect and preserve our nation’s most iconic and inspirational places for future generations. For more information, visit

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