RENO, Nev.— Public health, community and environmental groups have sued the U.S. Environmental Protection Agency for violating the Clean Air Act, with implications for air quality in several areas across the country, including Reno’s Washoe County. The EPA has missed the deadline for determining which areas of the country are failing to meet air quality standards for fine particulate matter, commonly known as soot.
“We’re going to court to stop Trump’s EPA from exposing Washoe County residents to more soot pollution and the greater risk of cancer and choked lungs that comes with it,” said Ryan Maher, a staff attorney at the Center for Biological Diversity, one of the groups bringing the lawsuit. “No one voted for more asthma attacks or heart attacks, but that’s what this administration is delivering. It’s another infuriating example of the Trump administration putting polluters before people.”
In 2024 the Biden administration strengthened the national air quality standard for soot to better protect public health. Under the Clean Air Act, the EPA was then required to designate areas of the country that are not meeting this new standard by February 7, 2026. This step triggers several obligations and deadlines for the EPA and states, requiring them to clean up this pollution as quickly as possible.
The half-million people living in Washoe County are exposed to levels of soot pollution that exceed the health-based standard for soot, based on the EPA’s air-monitoring data, making Washoe County a candidate for designation and clean-up obligations. In 2025 the American Lung Association named Reno the 6th most polluted city in the nation for particle pollution.
Monday’s lawsuit, filed by 17 groups in the U.S. District Court for the Northern District of California, asks the court to give the EPA a deadline for designating which U.S. areas are violating clean air standards.
“My students deserve to live in a community where they can breathe fresh air and play outside without harming their health,” said Nevada Assemblymember Selena La Rue Hatch, a high school teacher who represents Washoe County’s District 25 and submitted a declaration supporting the lawsuit. “Instead of shielding our residents and our children, who are most at risk, the EPA is protecting the profits of the corporate polluters.”
Soot consists of tiny particles 30 times smaller than the width of a human hair. Because of their small size, soot particles penetrate deep into the lungs and can enter the bloodstream, causing health harms like premature death, aggravated asthma, and heart and lung damage. Children, the elderly, communities of color, and low-income groups are most at risk.
More than 7,000 children suffer from pediatric asthma in Washoe County, and about one in 10 adults in Washoe County have asthma. Significant sources of soot pollution in the county include transportation, smoke from wood stoves and fireplaces, wildfire smoke and industrial facilities.
In addition to missing the designations deadline, Trump’s EPA has repeatedly signaled its intent to do away with the strengthened standard. In 2024 the agency estimated that the standard could bring $46 billion in public health benefits.
More information about the Center’s fight against air pollution is available at Protecting Air Quality Under the Clean Air Act.
