Coal-fired power plants responsible for 460,000 US deaths since 1999, study finds

Between 1999 and 2020, more than 460,000 deaths in the United States were due to exposure to air pollution emissions from coal-fired power plants, according to the longest-running national study of its kind. While the findings highlight the increased mortality risks from coal-fired power generation, they also highlight the effectiveness of emission reduction policies in preventing excess death. Exposure to air pollution is associated with poor health and an increased risk of death. Coal-fired electric generating units (EGUs), also known as power plants, are a major contributor to poor air quality. Although EGU coal air pollution emissions have declined in the US in recent decades, global use of coal for electricity generation is projected to increase. Recent studies have shown that exposure to fine particles (PM_2.5) containing sulfur dioxide (SO₂) from coal combustion emissions are deadlier than PM_2.5 from other sources. Policymakers seeking to limit the impact of coal use justify regulations by quantifying the health burden attributable to exposure to these sources. However, measuring the magnitude of the impact of carbon EGU-derived air pollution on human health, as well as the success of measures to mitigate these impacts, is challenging. Efforts have been hampered by the limited availability of large-scale health databases and source-specific exposure estimates.

To better estimate US deaths attributable to PM exposure_2.5 emitted by coal-fired power plants and how related mortality patterns have changed over time, Lucas Henneman and colleagues combined a reduced-complexity atmospheric transport model, which they used to estimate emissions from 480 individual coal EGUs , with historical death at the individual level in the US. records spanning more than 650 million man-years. They found that exposure to coal-derived PM_2.5 was associated with a 2.1-fold greater risk of mortality than PM exposure_2.5 from all other sources. And, carbon-derived PM_2.5 was responsible for 460,000 cumulative deaths among people over 65 years of age over the past two decades, accounting for ~25% of total PM-attributable deaths_2.5. According to the findings, the mortality burden of coal PM_2.5 has been underestimated. Reviews, Henneman et al. also show that the rapid reduction of sulfur dioxide (SO₂) emissions from coal-fired power plants over the past 20 years—through emissions reduction regulations and coal EGU shutdowns—have led to a large reduction in excess deaths. In a related perspective, Robert Mendelsohn and Seung Min Kim discuss the study and its limitations in more detail. Note: The authors have provided an interactive online tool that shows how deaths attributable to each individual US coal EGU have changed over time.