Study finds patients near US Steel plant had worse asthma after 2018 fire

Blaze knocked out sulfur pollution controls for 3 months

Reid Frazier

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Reid R. Frazier is an energy reporter for The Allegheny Front, a Pittsburgh-based public media outlet covering the environment in Pennsylvania. His work has aired on NPR and Marketplace.

A Dec. 24, 2018 fire damaged a section of US Steel's Clairton Coke Works. Photo: US Steel

May 6, 2021 | 3:26 PM

A new study found residents living near a US Steel plant in the Pittsburgh area experienced worse bouts of asthma and increased their use of breathing aides after a 2018 fire caused elevated air pollution in the area.

The Dec. 24, 2018 fire destroyed the pollution controls at US Steel’s Clairton Coke Works. For three months, the controls were offline, resulting in large releases of sulfur dioxide, a lung irritant that can make it harder to breathe, especially for people with asthma and other lung conditions.

Researchers asked asthma patients living near the plant whether their breathing got worse in those three months, then compared their answers to those from patients farther away.

“Significantly more people answered that question, ‘Yes,’ that lived close to the Clairton Coke Works than equivalent people who lived further away,” said study co-author Jim Fabisiak, associate professor of environmental and occupational health at the University of Pittsburgh. “Here you have the same period of time, you’re getting this differential response and it’s all at the same time, so it’s not sort of a seasonal allergy kind of thing.”

“I do remember saying I have never been this close to maybe having to go to the hospital because of that incident,” Kiss said. She upped the dosage of medications she uses to control her asthma, but her lungs still burned, she said. “Traditional medicines, closing windows just didn’t seem to help as much.”

Study co-author Sally Wenzel, chair of Pitt’s department of environmental and occupational health and director of the University of Pittsburgh’s Asthma and Environmental Lung Health Institute at UPMC, said other studies have been unclear as to whether increased sulfur dioxide (SO2) emissions can worsen asthma symptoms for patients. She said the study adds further evidence that it does.

“I think our data were at least very strongly associated with the peak in SO2 emissions and pollutant levels,” Wenzel said. She said other studies have shown this type of exposure could potentially lead to “long term effects” on patients’ lungs.

Wenzel said asthma afflicts about 8 to 10 percent of the county’s population.

About half the patients living near the plant did not know about the fire or that increased sulfur dioxide emissions had worsened air quality near them. Wenzel said that showed there was a lower potential for bias in the study.

“There was the same loss of asthma control and asthma exacerbation tendency in the group that knew about (the coke works fire) and the group that didn’t know about it,” Wenzel said.

The study found that sulfur dioxide emissions from the plant averaged “between 40 and 50 tons per day” or about 25 times higher than typical levels. Ambient air pollution measurements near the plant were also higher after the fire compared to prior years.

The study appears in the Journal of Allergy and Clinical Immunology. It was funded by the National Institutes of Health and the Heinz Endowments. (The Heinz Endowments also funds the Allegheny Front.)

The study found that after pollution controls went back online, conditions improved for a group of patients that responded to a follow-up survey.

Jonathan Buonocore, a research scientist at the Center for Climate, Health and the Global Environment at the Harvard T.H. Chan School of Public Health, said the researchers used the coke works fire as a “natural experiment” to show something that scientists have known for a while: air pollution is bad for peoples’ health.

“It’s yet another piece of evidence showing that air pollution is related to respiratory disease and reducing emissions of air pollution reduces rates of respiratory disease,” said Buonocore, who was not involved with the study. “It shows that these types of industrial sources can have pretty focused health impacts on the communities that live nearby.”

US Steel says it spent $300 million on environmental improvements on the site since the fire, and is in favor of some enhanced public communication system to make the public more aware of air quality near its facilities in the Mon Valley.

“Safety and environmental performance remain our top priorities, and we value our commitments to our employees, communities and the environment,” said company spokeswoman Amanda Malkowski, in a statement.