air pollution heart attack

ER visits for heart problems plummeted after Pittsburgh coal processor shut down

Levels of one highly-toxic pollutant fell by 90% and ER visits for heart problems decreased by 42% immediately after the shutdown.

PITTSBURGH—The closure of one of Pittsburgh’s largest coal-processing plants in 2016 led to a lasting reduction in hazardous air pollution and a decrease in heart-related hospital visits, according to a new study.


The Shenango Coke Works, located on Pittsburgh’s Neville Island, processed coal into coke, a key ingredient in steelmaking, until its closure in January 2016. Producing coke requires heating coal to extremely high temperatures, which releases a slew of hazardous pollutants.

The study, published in Environmental Health Research and led by researchers at New York University’s Grossman School of Medicine, looked at pollutants in air monitoring data and at emergency room visits and hospitalizations for heart problems before and after the plant’s closure. The research was prompted in part by previous Environmental Health News (EHN) reporting on the plant closure, in which questions were raised by the Allegheny Health Department about links between air pollution decreases and fewer ER visits for asthma and heart problems.

“Closing this plant and eliminating its pollution really had a dramatic health benefit on the communities living nearby,” George Thurston, one of the study’s coauthors and director of the Program in Exposure Assessment and Human Health Effects at the Department of Environmental Medicine at NYU’s medical school, told EHN.

“We saw a dramatic, immediate decline in emergency room visits and hospitalizations for cardiovascular issues and then over the next several years they kept declining,” Thurston said, noting that these accumulated health benefits are similar to those seen when people quit smoking.

The study found that average weekly hospital visits among residents in neighborhoods surrounding the plant for heart-related problems decreased by 42% immediately after the shutdown. The trend continued over the next three years, with 33 fewer average yearly hospitalizations for heart disease from 2016 through 2018 compared to the three years preceding the plant closure.

The study also found that average daily levels of sulfur dioxide, a byproduct of cokemaking linked to respiratory and heart problems, fell by 90% at government air-monitoring stations near the plant and by 50% at another air-monitoring station about six miles away in Pittsburgh’s Lawrenceville neighborhood. Arsenic in particulate matter, another toxic byproduct emitted from the plant, fell by 66% at the monitors near the plant.

A lethal air pollution combination

coal pittsburgh air pollution

Neville Island’s Shenango Coke Works Plant in operation before the plant’s 2016 closing.

Credit: Brian Cohen for The Heinz Endowments

Previous research by the Allegheny County Health Department, which oversees air quality in the region, found that ER visits for asthma dropped 38% and visits for heart problems decreased by 27% the year after the closure of Shenango Coke Works, but local health officials were reluctant to attribute the change to the plant shutdown.

At the time, local health officials told EHN that the changes they’d observed in particulate matter pollution after the plant’s closure weren’t substantial enough to cause such a dramatic drop in emergency room visits for asthma, based on what they’d seen in other studies. But in the last several years, a growing body of research indicates that the source and makeup of particulate matter pollution determine how toxic it is.

“Coal-related particulate matter is more toxic than other types of particulate matter pollution,” Wuyue Yu, the new study’s lead author and a doctoral science student at NYU, told EHN. “So the significant reduction of these types of particles could explain why such a small change in overall particulate matter pollution had such a dramatic effect.”

Thuston pointed to other research showing that these coal-derived pollutants are rich in transition metals and sulfur, which he referred to as a “lethal combination.”

“Sulfur itself isn’t the big problem, but it’s acidic, which makes these transition metals more bioavailable throughout the body,” he explained, pointing to a 2021 study showing that places with higher levels of transition metals and sulfur in their air had higher cardiovascular mortality rates. “Absorbing these particles in our bodies creates oxidative stress, which is linked to all kinds of health problems.”

“It’s imperative for our health that we stop burning fossil fuels”

The Pittsburgh region is still home to the largest coke-making plant in the country, U.S. Steel’s Clairton Coke Works, which is also one of the oldest operational coke plants in the country. In terms of production, the Clairton Coke Works is about ten times as large as the Shenango Coke Works was. The site lacks modern pollution controls, and the company is regularly fined for violating clean air laws at the site, but local activists say the fines are too low to incentivize change, calling it a “pay-to-pollute” model. Residents in Clairton regularly face some of the dirtiest air in the country and children at Clairton elementary school have asthma at nearly double the national rate.

In 2018, the Allegheny County Health Department said they’d observed a decrease in particulate matter pollution at air monitors near the Clairton Coke Works similar to what was seen following the closure of Shenango during the same time period, but hadn’t seen any of the same decrease in ER visits. At the time, they said this pointed to causes other than Shenango’s closure for the reduction in ER visits, so the researchers at NYU compared air pollution at monitors near the Clairton Coke Works with the pollution at monitors near Shenango, and found a significant difference in those “lethal combination” pollutants.

“At the monitors near Shenango, we saw a significant drop in sulfate, arsenic and selenium right after the closure and then consistently over the next three years,” Yu said. “At the monitors near the Clairton plant, we saw both spikes and overall higher levels of sulfate, arsenic and selenium over the same time period.”

The researchers also looked at other health effects in the years before and after the plant’s closure, including childhood asthma. They said they observed similar patterns, but those findings haven’t been published yet. The reduction in airborne arsenic, a potent carcinogen, will likely contribute to a reduction in cancer rates over time, though that data won’t be available for several decades.

“Our study adds to the evidence suggesting that when we just look at overall particulate matter levels without considering the sources and makeup of that pollution, we’re grossly underestimating the health benefits of shutting off fossil fuel pollution,” Thurston said.

“It’s imperative for our health that we stop burning fossil fuels. The climate benefits are important, though they may feel more distant, and our research clearly indicates that the health benefits are immediate and local.”

Editor’s note: This study was funded by the Heinz Endowments, which also provides funding to Environmental Health News.

People advocating against the US hydrogen hub build out
Credit: Top right photo - Kristina Marusic for EHN; other photos courtesy of Jennifer Gazdick for Just Transition Northwest Indiana

Hydrogen hubs test new federal environmental justice rules

A massive push for hydrogen energy is one of the first test cases of new federal environmental justice initiatives. Communities and advocates so far give the feds a failing grade.

Keep reading...Show less
Senator Whitehouse & climate change

Senator Whitehouse puts climate change on budget committee’s agenda

For more than a decade, Senator Sheldon Whitehouse gave daily warnings about the mounting threat of climate change. Now he has a powerful new perch.
photos of people protesting the hydrogen hub buildout
Credit: Left: Fred Stine, Delaware Riverkeeper Network; middle: Kristina Marusic for EHN; right: Ray Bailey

What’s hampering federal environmental justice efforts in the hydrogen hub build-out?

Keep reading...Show less
Lee Zeldin Trump's EPA administrator
Credit: Gage Skidmore/Flickr

Trump taps Zeldin to lead EPA with plans to ease climate restrictions

President-elect Trump has chosen Lee Zeldin, a former New York congressman with a conservative track record on environmental issues, to lead the Environmental Protection Agency as Trump moves to dismantle climate regulations.

Coral Davenport and Lisa Friedman report for The New York Times.

Keep reading...Show less
climate protestor holds up a 1.5 degree Celsius sign

Trump may move faster to exit Paris Agreement in second term

President-elect Donald Trump is expected to exit the Paris climate agreement again, likely with fewer obstacles, potentially leaving the U.S. out of global climate efforts sooner than in 2017.

Sara Schonhardt reports for POLITICO.

Keep reading...Show less
immigration office

Study links climate-driven extreme weather to rising migration between US and Mexico

Extreme weather tied to climate change is driving more undocumented migration between Mexico and the U.S. as droughts, heat, and storms threaten livelihoods in Mexico’s agricultural regions, according to new research.

Dorany Pineda reports for The Associated Press.

Keep reading...Show less
tree damage along a road

Report: Extreme weather’s global economic toll hits $2 trillion over the last decade

The world has lost $2 trillion in the past decade due to extreme weather, with the U.S., China, and India bearing the highest economic losses, according to a new report commissioned by the International Chamber of Commerce (ICC).

Ajit Niranjan reports for The Guardian.

Keep reading...Show less
man installing solar panels on roof

New members of Congress could resist environmental rollbacks under GOP control

As Republicans reclaim control of the Senate and potentially the House, newly elected pro-environment members of Congress may serve as a check on climate policy rollbacks planned by the GOP and the incoming Trump administration.

Wyatt Myskow, Dennis Pillion, Georgina Gustin, and Phil McKenna report for Inside Climate News.

Keep reading...Show less
From our Newsroom
photos of people protesting the hydrogen hub buildout

Los obstáculos para garantizar la justicia ambiental en los centros de hidrógeno federales

“El cambio organizacional en las grandes burocracias lleva tiempo”.

People advocating against the US hydrogen hub build out

Los centros de hidrógeno ponen a prueba las nuevas normas federales de justicia ambiental

El impulso masivo a la energía del hidrógeno es la primera prueba de fuego de las nuevas iniciativas federales de justicia medioambiental. Hasta ahora, comunidades y activistas le dan una pésima calificación al gobierno federal.

Donald Trump

Donald Trump wins US presidency. What that could mean for the environment.

His first term and recent campaigns signal massive deregulation and a reshaping of agencies.

Donald Trump (left) and Kamala Harris (right) on a split screen

2024 election: Two radically different visions for environment, health

Americans’ choice will have immediate and lasting effects on our planet. Here’s how.

Residents from Pennsylvania's Mon Valley region listen to local and national candidates speak about environmental issues

Pennsylvania voters press local, national candidates on fracking just days before election

Environmental justice communities near fracking want more answers — less political football.

U.S. Steel Pennsylvania pollution

Coal-based steelmaking in Pennsylvania causes up to 92 premature deaths and $1.4 billion in health costs every year: Report

Just three facilities near Pittsburgh cost the state $16 million in lost economic activity annually, according to a new report.

Stay informed: sign up for The Daily Climate newsletter
Top news on climate impacts, solutions, politics, drivers. Delivered to your inbox week days.