Press Release May 1, 2018

EPA Declares Regions Exceeding Ozone Limits: Areas Include More than 95 National Parks

EPA unveils what national parks are in areas that are not meeting the new, more protective ozone limit.

WASHINGTON – The Environmental Protection Agency (EPA) has declared that more than 95 of America’s national parks are failing to meet federal limits for ozone pollution. These parks include Cuyahoga National Park in Ohio and Sequoia Kings Canyon in California, where ozone threatens the health of park visitors and contributes to the disease and death of park species such as the black cherry tree in the East and aspen and ponderosa pine in the West. National park ecosystems across the country are already showing damage from ground-level ozone pollution.

Ozone pollution, sometimes referred to as smog, forms when emissions from oil and gas, automobile, coal-fired power plant and other sources are exposed to sunlight. It can worsen asthma, damage the developing lungs of children, and cause premature death from heart and lung disease. EPA’s recent action officially designates those areas of the country that are not in compliance with federal ozone standards.

The EPA’s declaration follows the recent victory by National Parks Conservation Association (NPCA) and nine other conservation and health groups in a lawsuit against EPA over its refusal to enforce the 2015 standards, resulting in deadlines for the final designation of all areas in the country not meeting ozone standards.

The following is a statement by Stephanie Kodish, NPCA’s Clean Air Program Director:

“EPA’s decision kick starts requirements for states to limit the pollution that causes ozone problems in national parks and other areas. While we value this necessary step, we cannot ignore the administration’s transparent hostility not only to critical protections for our public health and national parks, but also to science.

“Higher asthma rates, diminished visibility, and harms to sensitive species should push us to embrace science and do more to combat ozone pollution, but the administration appears only committed to inventing a fantasy where industry interests govern the design of laws that are supposed to protect our country’s air and national parks.

“Safeguarding public health and park ecosystems isn’t just about going through the motions, it is about drawing on the robust and growing body of science to inform the degree to which we must clean up our air. We call on EPA to ensure that the pollution causing high levels of ozone be cleaned up.”


About National Parks Conservation Association. Since 1919, the nonpartisan has been the leading voice in safeguarding our national parks. NPCA and its more than 1.3 million supporters work together to protect and preserve our nation’s natural, historical, and cultural heritage for future generations. For more information, visit

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