The road to the Clean Air Act goes through Pittsburgh

He created this story Scientific Friday.

In the 1960s, America’s urban air pollution crisis was at its height: cities were shrouded in smog, steelworkers unions demanded health protections, and the Justice Department filed an antitrust suit against Detroit automakers for conspiring to pollute. .

But that all changed when Richard Nixon signed the Clean Air Act of 1970. The law established national limits for six major pollutants, set strict emissions standards for vehicles, and required the latest pollution control technologies for industrial facilities. It was widely recognized as innovative, landmark legislation because it was fact-based, future-ready and had teeth.

Since the Clean Air Act went into effect, emissions of the most common pollutants have fallen by about 80%. The law has saved millions of lives and trillions of dollars. An EPA analysis found that the benefits of the Clean Air Act outweighed the costs by a factor of 30. Thanks to these policies, the United States has some of the cleanest air in the world.

But five decades later, has the Clean Air Act protected everyone? And can policies aimed at addressing the problems of mid-century urban cities protect our health in the face of climate change?

Pittsburgh and the road to clean air

In many ways, the history of the Clean Air Act begins in Pittsburgh, Pennsylvania, decades before it was signed into federal law. In the 1940s and 1950s, Pittsburgh was the world capital of steel production. Ironworks and blast furnaces lined the city’s famous three rivers, burning bituminous coal from the surrounding hills and pouring dark smoke from brick chimneys and chimneys.

“(Pittsburgh) was one of the most polluted places on the planet,” said Matt Mehalik, executive director of the human rights nonprofit Breathe Project.

The smoke and dust hung so thick in the air that it blocked out the sun, and the city had to turn on its street lights in the middle of the day so that people could go about their business in the city. Metal ash settled on the houses and damaged the paint from the residents’ cars. Even hanging clothes to dry on the lines was risky.

“Sometimes you look up and run out, take the wet clothes off the assembly line because you see soot and stuff,” said Art Thomas, a longtime Pittsburgh resident and former US Steel employee. “If you didn’t get them off the line, you had to wash your clothes again.”

Pollution was seen as the price residents had to pay for Pittsburgh’s prosperity, but the impact on public health was not yet well understood.

Then, in 1948, a wake-up call rang out from a small mill town called Donora in the river valley south of Pittsburgh. A blanket of warm air, known as a temperature inversion, settled over the river valley like a lid, trapping cooler air — and air pollution from Donora’s industrial facilities — close to the ground for five days. By the time the inversion broke and the smog cleared, 20 people had died and another 6,000 were sickened in the city of 14,000.

“It was a really terrible turning point in the history of the United States,” Mehalik says. “That smog incident in Donor … set in motion various efforts to control air pollution.”

The following year, in 1949, Allegheny County, where Pittsburgh is located, passed its first air pollution control law. Over the next 20 years, much of the city’s thick, visible smoke cleared, and regulators honed new skills in controlling air pollution. The results were impressive: in 1949, an average of 170 tons of dust fell per square mile in Allegheny County every month. By 1969, this number had dropped to 38 tons.

“A lot of the policy that was put in place by the EPA when it was created in the 1970s grew out of our experience trying to curb pollution here in Pittsburgh,” Mehalik says.

“Where there is pollution, there is cancer”

Although many experts tout the Clean Air Act as one of the most successful environmental policies in United States history, it is also widely acknowledged to have failed to address pollution problems in many communities of color and high-poverty areas.

Perhaps the most famous of these is the area called Cancer Alley along the Mississippi River between Baton Rouge and New Orleans in Louisiana. It is a stretch of 184 river miles where more than 300 industrial facilities, most of them petrochemical, emit dangerous air pollutants. One of the most important is ethylene oxide, a colorless gas used to make products such as plastics and antifreeze. It is a known carcinogen that increases the risk of blood and breast cancer.

Dr. Kim Terrell and Gianna St. Julien are Tulane Environmental Law Clinic researchers and co-authors study in 2022 which links high rates of cancer to pollution on Cancer Alley. Their research has shown that cancer rates in some communities are 35-40% higher than the national average. It confirmed what locals had been saying for decades.

“People have always said, ‘Hey, where there’s pollution, there’s cancer,'” says Terrell. “And our research confirms that where there’s pollution in Louisiana, there’s cancer.”

Lisa Jordan directs the Tulane Environmental Law Clinic. She says hot spots like Cancer Alley can exist because “the Clean Air Act doesn’t really have a program specifically designed to monitor and protect every community from breathing in toxic air.”

The Clean Air Act provides two main ways to deal with pollution. The first is the National Program of Ambient Air Quality Standards. It requires state, local, and tribal air agencies responsible for implementing the Clean Air Act to monitor and limit six common pollutantssuch as lead and particulate matter in ambient air. Under this program, pollution standards are clear, monitoring methods are well established, and compliance is relatively simple: a region either meets the standard or it doesn’t. If it doesn’t, it must submit a special plan to the EPA that shows how it will comply. Failure to do so triggers sanctions.

The Clean Air Act’s second major pollution control measure is to limit emissions of 188 less common “hazardous air pollutants,” mostly from large industrial facilities. This approach is two-pronged: First, EPA requires agencies to use the latest and best pollution control technologies. It then looks at what health risks remain after those controls are in place to determine whether stricter standards are needed. But unlike the six common pollutants, hazardous air pollutants are not continuously monitored in ambient air.

Terrell says this could make it possible for dangerous concentrations of these dangerous air pollutants to exist.

“There’s no substitute for community air monitoring, because you may have control technologies that aren’t working as well as you thought, or you may have leaks or other sources of fugitive emissions that you’re not accounting for,” Terrell says. “So you don’t know what people are exposed to unless you measure that exposure.”

However, hazardous air pollutants are notoriously difficult to measure. But recently, environmental engineers at Johns Hopkins University used a mobile lab to measure actual ethylene oxide concentrations in Cancer Alley. They found levels of the gas 10 times higher than EPA estimates, and a thousand times higher than what is considered safe for long-term exposure.

Forest fire smoke and a loophole for clean air

The Clean Air Act was designed to clean up urban air pollution emitted from smokestacks and exhaust pipes. Events such as forest fires are therefore a problem. And as wildfires have become more frequent and the wildfire season longer, jurisdictions have turned to sequestration to help them meet air quality standards.

It’s known as the “emergency rule,” and it allows air agencies to petition the EPA for an exception when a pollution event, such as a wildfire, is beyond their control. The exemption allows the agency to comply with national ambient air quality standards even if the measured pollution would push the region above the allowable limit.

When an exceptional event is granted to an air agency, the pollution associated with that event remains visible for research purposes, but it no longer affects the “design value” of the area. The design value this is how the EPA determines whether or not an area meets pollution limits.

Health reporter Molly Peterson says it’s like erasing pollution from a government accountability perspective. She continued to work investigative series for The Guardian on the use of exceptional events, which was published last year. Her team’s analysis found that 21 million Americans live in areas where an exceptional event allowed regulators to report that the air became cleaner than it was. And it’s likely to be on the rise: In 2016, 19 wildfires were flagged by United States aviation agencies as potential exceptional events. In 2020, there were 65 of them.

“It just seems like something worth counting,” Peterson says of air pollution, which is considered an exception. “If no one is taking responsibility for the problem in the air, then no one is going to … put more resources into it.”

Peterson believes a new legislative framework may be needed to address poor air quality caused by climate change.

“The Clean Air Act is still this absolutely amazing piece of legislation without which we wouldn’t be breathing and without which my skies in Los Angeles wouldn’t be clear right now,” Peterson says. “Despite this, circumstances have changed and the law has not yet had time to notice it.”