For Immediate Release, April 2, 2020


Robert Ukeiley, (720) 496-8568,

Lawsuit Launched Challenging Trump EPA’s Delay in Cleaning Up Smog in Denver, Front Range

DENVER— Conservation groups filed a formal notice today of their intent to sue the Environmental Protection Agency for delays in reducing dangerous smog pollution in the greater Denver region.

The Center for Biological Diversity and Center for Environmental Health are calling on the Trump administration’s EPA to ensure that industrial polluters comply with air-quality standards for smog and to ensure effective state or federal plans are in place that protect public health and special places like Rocky Mountain National Park. The EPA recently designated Denver as a “serious” violator of federal air-quality standards for smog.

Multiple studies have found air pollution, including smog, can exacerbate the susceptibility to, and severity of, respiratory virus infections. Existing respiratory health problems contribute to increased risks for individuals sickened by COVID-19.

The area covered by today’s action is home to around 3.5 million people — over half of Colorado’s population. It includes Denver, Boulder, Greeley, Fort Collins and Loveland.

“Over half the people living in Colorado are breathing dangerously unsafe air,” said Robert Ukeiley, an attorney at the Center for Biological Diversity. “The EPA’s refusal to take action on polluters running amok has left us with no choice but to take them to court.”

People exposed to excess ground-level ozone, the principle pollutant in smog, can experience reduced lung function, increased respiratory problems like asthma attacks, increased visits to emergency rooms and even premature death.

One study in China found that air pollution increased the number of deaths from severe acute respiratory syndrome (SARS) and that the variable levels of mortality from SARS in mainland China corresponded to air-pollution levels.

“Every second of delay allows more pollution to enter our environment and puts more people at risk of respiratory problems and the COVID-19 pandemic,” said Caroline Cox, research director at the Center for Environmental Health. “We must fight against the Trump administration to ensure safe, clean breathable air for all Americans.”

Beyond human health concerns, the conservation groups are concerned about ozone pollution’s harm to wildlife and plants. Ozone exposure can stunt the growth of trees and damage their leaves. It also increases susceptibility to disease, harms from insects and harsh weather. Sensitive tree species at risk from ozone exposure include quaking aspen, cottonwood and ponderosa pine.

Ponderosa pine is habitat is critical to protected species such as the threatened Mexican spotted owl and threatened Pawnee montane skipper butterfly.

Denver's smog-choked skyline/courtesy Dennis Schroeder
Denver's smog-choked skyline/courtesy of Dennis Schroeder Image is available for media use.

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 1.7 million members and online activists dedicated to the protection of endangered species and wild places.

The Center for Environmental Health works with parents, communities, businesses, workers, and government to protect children and families from toxic chemicals in homes, workplaces, schools and neighborhoods.