New paper in Science quantifies mortality risk from power-plant pollution

Nathan Kahl — Mon, 27 Nov 2023 14:24:43 +0000

New paper in Science quantifies mortality risk from power-plant pollution Nathan Kahl Mon, 11/27/2023 - 09:24

In This Story

Exposure to fine particulate air pollutants from coal-fired power plants (coal PM2.5) is associated with a risk of mortality more than double that of exposure to PM2.5 from other sources, according to a new study led by George Mason University, the University of Texas at Austin, and Harvard T.H. Chan School of Public Health.

Examining Medicare and emissions data in the U.S. from 1999 to 2020, the researchers also found that 460,000 deaths were attributable to coal PM2.5 during the study period—most of them occurring between 1999 and 2007 when coal PM2.5 levels were highest.

While previous studies have quantified the mortality burden from coal-fired power plants, much of this research has assumed that coal PM2.5 has the same toxicity as PM2.5 from other sources.

“PM2.5 from coal has been treated as if it’s just another air pollutant. But it’s much more harmful than we thought, and its mortality burden has been seriously underestimated,” said lead author Lucas Henneman, assistant professor in the Sid and Reva Dewberry Department of Civil, Environmental, and Infrastructure Engineering at Mason. “These findings can help policymakers and regulators identify cost-effective solutions for cleaning up the country’s air, for example, by requiring emissions controls or encouraging utilities to use other energy sources, like renewables.”

Using emissions data from 480 coal power plants in the U.S. between 1999 and 2020, the researchers modeled where the wind carried coal sulfur dioxide throughout the week after it was emitted and how atmospheric processes converted the sulfur dioxide into PM2.5. This model produced annual coal PM2.5 exposure fields for each power plant. They then examined individual-level Medicare records from 1999 to 2016, representing the health statuses of Americans ages 65 and older and representing a total of more than 650 million person-years. By linking the exposure fields to the Medicare records, inclusive of where enrollees lived and when they died, the researchers were able to understand individuals’ exposure to coal PM2.5 and calculate the impact it had on their health.

Deaths from power-plant emissions have dropped steeply in recent years.

They found that across the U.S. in 1999, the average level of coal PM2.5 was 2.34 micrograms per cubic meter of air (μg/m3). This level decreased significantly by 2020, to 0.07 μg/m3. The researchers calculated that a one μg/m3 increase in annual average coal PM2.5 was associated with a 1.12% increase in all-cause mortality, a risk 2.1 times greater than that of PM2.5 from any other source. They also found that 460,000 deaths were attributable to coal PM2.5, representing 25% of all PM2.5-related deaths among Medicare enrollees before 2009.

The researchers were also able to quantify deaths attributable to specific power plants, producing a ranking of the coal-fired power plants studied based on their contribution to coal PM2.5’s mortality burden. They found that 10 of these plants each contributed at least 5,000 deaths during the study period. They visualized the deaths from each power plant in a publicly available online tool (https://cpieatgt.github.io/cpie/).

The study also found that 390,000 of the 460,000 deaths attributable to coal-fired power plants took place between 1999 and 2007, averaging more than 43,000 deaths per year. After 2007, these deaths declined drastically, to an annual total of 1,600 by 2020.

“Beyond showing just how harmful coal pollution has been, we also show good news: Deaths from coal were highest in 1999 but by 2020 decreased by about 95%, as coal plants have installed scrubbers or shut down,” Henneman said.

“I see this as a success story,” added senior author Corwin Zigler, associate professor in the Department of Statistics and Data Sciences at UT Austin and founding member of the UT Center for Health & Environment: Education & Research. “Coal power plants were this major burden that U.S. policies have already significantly reduced. But we haven’t completely eliminated the burden—so this study provides us a better understanding of how health will continue to improve and lives will be saved if we move further toward a clean energy future.”

The researchers pointed out the study’s continuing urgency and relevance, writing in the paper that coal power is still part of some U.S. states’ energy portfolios and that global coal use for electricity generation is even projected to increase.

“As countries debate their energy sources—and as coal maintains a powerful, almost mythical status in American energy lore—our findings are highly valuable to policymakers and regulators as they weigh the need for cheap energy with the significant environmental and health costs,” said co-author Francesca Dominici, Clarence James Gamble Professor of Biostatistics, Population, and Data Science at Harvard Chan School and director of the Harvard Data Science Initiative.

Topics

environmental engineering

coal emissions

coal-fired power plants

Air Pollution

CEIE Success Stories

CEC faculty research

Mason Engineering researcher investigates air pollution’s impact on health

Nanci Hellmich — Tue, 29 Sep 2020 18:46:04 +0000

Mason Engineering researcher investigates air pollution’s impact on health Nanci Hellmich Tue, 09/29/2020 - 14:46

Environmental researcher Lucas Henneman is investigating air pollution’s impact on health.

He uses large datasets and computer models to track pollution after it’s emitted from sources such as automobiles, coal power plants, and natural gas plants. The models help identify which people in nearby communities breathe in pollution.

“Each source leaves its air pollution fingerprint on the surrounding area, and we use those fingerprints to study how each source has impacted air quality over time and how that has affected people’s health,” says Henneman, an assistant professor in the Sid and Reva Dewberry Department of Civil, Environmental, and Infrastructure Engineering (CEIE). His research is funded by the United States Environmental Protection Agency and the non-profit Health Effects Institute.

He has found that emission reductions from power plants and automobiles over the last 20 years have reduced the incidence of some health problems including cardiovascular and respiratory conditions.

Overall, the air quality is better in the United States now than it was 10, 20, and 50 years ago, he says. “I like that my research starts with a success story. We’ve made impressive strides to clean our air, but there’s more work to be done to keep people healthy.”

Some estimates suggest that more than 100,000 Americans die each year from illnesses caused by air pollution, Henneman says. “We are developing models and devising new analytical techniques to create evidence for continued improvements in environmental policy. We’re looking at where to make emissions reductions, so we get the best return on our investment moving forward."

Henneman is also part of a group of experts looking at air pollution in China, which has made progress in recent years but still experiences unhealthy levels of air pollution, he says.

Laura Kosoglu, associate chair of CEIE, says, “Improving air quality is one of those goals where it’s not a question of if we should do it. The question is how to improve air quality efficiently and effectively, and Lucas’s research directly considers the impacts on public health. We are excited to have Lucas join our department.”