Celebrating 40 Years, Clean Air Act Faces New Threats

It sounds like something out of a 1950s Saturday matinee: The Killer Fog. But in the decades before Congress passed the landmark Clean Air Act, this phantom menace was no Hollywood bugaboo; it threatened the lives and health of millions of Americans. Take the town of Donora, Pennsylvania, 20 miles south of Pittsburgh. In October 1948, an air inversion trapped a blanket of toxic yellow smog from the town's steel mills that was so thick, locals needed flashlights in the middle of the afternoon. Five days later, 20 people had died and almost half of Donora's 14,000 residents had become sick.

If most Americans can no longer remember a time when the simple act of breathing could kill you, that's thanks in large part to the Clean Air Act. Although it took Congress more than 20 years after Donora's "killer fog" to pass the historic law, in the four decades since, it has proven to be one of the most important and successful pieces of environmental legislation ever enacted. Since 1990 alone, emissions of six of the most common air pollutants are down 41 percent, while such major sources of pollution as cars, trucks and heavy-duty diesel engines are 95 percent cleaner than in the past.

In 1970, Congress charged the newly created Environmental Protection Agency with regulating five harmful pollutants. But lawmakers understood that as science proved the hazards of other emissions, more would have to be added to the list. Today, the agency protects the public from more than 300 pollutants. Among those most recently added are carbon dioxide and other gases that cause global warming.

Yet if the price of liberty is eternal vigilance, it seems that the same can be said for clean air. Earlier this year, Sen. Lisa Murkowski (R-AK) introduced a resolution that would effectively overturn a 2007 Supreme Court ruling and block the EPA from using the Clean Air Act to regulate emissions that are contributing to drastic climate change. A separate bill proposed by Sen. Jay Rockefeller (D-WV) would prevent the EPA from working to address greenhouse gases for a minimum of two years. NRDC is campaigning against both measures, continuing our decades-long tradition of opposing those who would put politics over sound science and weaken one of our most vital environmental laws.