September 27, 2011

Visitors to America’s hundreds of national parks typically expect to find clean, fresh air. But many parks are reporting ozone levels above the health standard. A new report by the National Parks Conservation Association shows ozone pollution levels exceeded health-based standards more than 200 times at 18 of the national parks with ozone monitors. That’s the highest level in three years and resulted in several ‘Code Red’ days when even healthy people are advised to avoid vigorous outdoor exercise.

The Air Resources Division of the National Park Service has air monitoring systems set up in about 70 national parks around the country. The parks service says Yosemite, Sequoia and Kings Canyon national parks experienced some of the worst air pollution of any national parks in the U.S. since they are downwind of many pollution sources including industry, agriculture and major highways.

Studies show breathing ozone can trigger health problems including asthma, chest pain, coughing, throat irritation and congestion. The National Parks Conservation Association is urging Congress not to pass legislation that would roll back important protections against harmful air pollution. There are currently two measures moving through Congress which would weaken the Environmental Protection Agency’s air quality regulations.