Saturday, November 23, 2019
In findings published Wednesday in Environmental Science and Technology, researchers from the University of Washington and Stanford University reported that premature deaths in the United States attributable to the pollution produced by power plants were disproportionately caused by coal; that race was a significant factor in who was affected; and that a substantial fraction of the deaths were from pollution crossing state lines.
The study focused on particulate matter, or PM2.5, specifically airborne particles under 2.5 micrometers in diameter. To track the movement of these particles across the United States, the research team established a reduced-complexity model, which can complete analyses faster than traditional models, so the team’s study could encompass nearly all the United States’ power plants.
Particulate matter in the air, like that produced at power plants, can cause lung problems, heart attacks and stroke, which then lead to premature death. In the United States alone, particulate matter is indirectly responsible for reportedly upwards of 100,000 deaths annually.
According to the study, in 2014 in the continental United States, roughly 16,000 premature deaths were attributable to power plants, an estimated 91% of those from coal. The researchers also found in 36 states most of the people who died were affected by pollution generated in another state. For example, 37% of the power plant pollution that reaches Ohio comes from plants in nearby Indiana.
The study’s lead author, doctoral candidate Maninder Thind, said, “We looked at emissions from different types of power plants — including coal, natural gas, diesel and oil power plants — and modeled how the pollutants would travel based on things like wind patterns or rain. We also consider how emissions can react in the atmosphere to form fine particle air pollution […] That gave us a map of pollution concentrations across the country. Then we overlaid that map with data from the census to get an estimate of where people live and how this pollution results in health impacts.”
Even after the researchers adjusted their data for economic factors, premature deaths from this type of pollution were stratified by race, with the highest likelihood for black Americans, at a rate of seven per 100,000 people. They were followed by non-Latino white Americans at six per 100,000; for all other racial groups in the country, there were only four premature deaths per 100,000. Income did affect people’s level of exposure but to a far less pronounced extent, a difference of one per 100,000 between annual incomes below US$10,000 versus above $200,000.
Another co-author, civil and environmental engineering professor Julian Marshall, said, “We’ve seen in our previous research that our society is more segregated by race than by income, and now it’s showing up again with air pollution from electricity generation emissions […] These results can help local, state or national governments make more informed decisions that will improve everyone’s air quality and quality of life.”
Marshall noted, “It’s especially relevant these days because of what the federal government is doing — or actually not doing — around air pollution and around these issues in general[.]”