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Your Environment. Your Health.

Asthma Declines With Lower Power Plant Emissions

Joan Casey, Ph.D.
Columbia University
K99/R00ES027023, K99/R00ES027511, R01ES026217

Asthma symptoms and asthma hospitalizations dropped dramatically in response to reduced power plant emissions, according to an NIEHS-funded study. The researchers took advantage of a natural experiment in Louisville, Kentucky, between 2013 and 2016. During that time, nearby power plants either stopped using coal as the energy source or installed better emission controls. This is the first study to link reduced emissions from coal-powered plants with asthma-related health benefits.

The team used dispersion modeling to estimate the movement of sulfur dioxide emissions from the plants and found that exposure decreased after the transition from coal to natural gas and the installation of emission controls. They also demonstrated that these changes were associated with fewer asthma-related hospitalizations and emergency room visits, and reduced use of asthma inhalers.

Specifically, by comparing emissions from the same areas before and after coal retirement, the researchers estimated that energy transitions in the spring of 2015 resulted in 12 fewer hospitalizations and emergency department visits per ZIP code in the following year. Their estimated results translate into nearly 400 avoided hospitalizations and emergency room visits each year across the county. Emission controls installed in 2016 were associated with a 17% drop in asthma inhaler use, and a 32% reduction in odds of using inhalers heavily throughout the month.

Citation: Casey JA, Su JG, Henneman LRF, Zigler C, Neophytou AM, Catalano R, Gondalia R, Chen Y, Kaye L, Moyer SS, Combs V, Simrall G, Smith T, Sublett J, Barrett MA. 2020. Improved asthma outcomes observed in the vicinity of coal power plant retirement, retrofit and conversion to natural gas. Nat Energy 5:398–408.

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