Health costs of coal plants twice as bad as originally thought
Recent research in the USA has revealed that air pollution from coal power plants was around twice as dangerous as previously thought, meaning that the introduction of air quality regulations and coal power plant retirements has been twice as beneficial as expected.
The researchers led by Dr. Lucas Henneman at George Mason University, the Harvard School of Public Health, and the University of Texas at Austin analysed a dataset of Medicare death records between 1999 and 2020. Looking at the locations of 480 separate coal power plants and modeling where air currents would distribute their emissions, they could estimate coal PM2.5 exposure where the people lived and died.
The Greenpeace airship A.E. Bates flies over the Portland Generating Station in Portland.
The team were motivated by the idea that previous work in this area has assumed that PM2.5 is equally damaging, regardless of its source. However, the PM2.5 emitted by coal plants contains sulfur dioxide, black carbon and metals, which they believed would have a more serious health impact.
From their research, the team calculated that for every 1 µg/m³ increase in coal PM2.5, mortality increased by 1.12% – more than twice the risk that was associated with PM2.5 exposure from all air pollution sources. The team estimated that between the dates they examined, the coal plants were responsible for around 460,000 excess deaths.
Ten of the coal plants studied (all located east of the Mississippi River) were responsible for over 5,000 deaths each, while 140 plants accounted for over 1,000.
Dr. Henneman said: ‘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.’
On the positive side, the study covered a time period in which pollution control technology was introduced to many plants, while others were retired. When such events happened, the deaths that had previously been associated with the plants declined. An example cited is a facility in Pennsylvania which was associated with an average of more than 600 deaths per year before installing emissions scrubbers. After scrubber installation, that number dropped to 80 per year.
Senior author Dr. Corwin Zigler of the University of Texas said: ‘I see this as a success story. Coal power plants were this major burden that U.S. policies have already significantly reduced.’
photo: Greenpeace
