Report ranks Cincinnati among the 25 most polluted cities in the country

Cincinnati is one of the worst cities in the country when it comes to yearly particle pollution, according to the American Lung Association’s 2024 State of the Air report.

Particle pollution occurs when tiny solid particles and liquid droplets from factories, power plants, and vehicles build up in the air. These particles get trapped in your lungs when you inhale them, leading to asthma attacks, heart attacks, and for those with heart or lung conditions, premature death.

Among the 25 cities with the highest particle pollution in the country, Cincinnati came in 22nd – tied with Chicago, but better than Indianapolis and Detroit. Cincinnati’s ranking improved from last year, when its particle pollution was 18th worst in the nation.

Here’s what else we learned from the American Lung Association’s report.

Four Ohio counties may exceed EPA’s 2024 pollution limits, Hamilton County the worst among them

Cincinnati’s Hamilton County had the highest annual particle pollution in Ohio, according to the American Lung Association’s analysis of U.S. EPA data between 2020 and 2022.

Hamilton County had 10.5 micrograms per cubic meter of air, worse than both Cuyahoga County, where Cleveland is located, and Franklin County, home to Columbus. 

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Previously, all counties met the federal limit of 12 micrograms per cubic meter of air.

However, in February, the U.S. Environmental Protection Agency lowered the yearly limit for particle pollution to nine micrograms – a move expected to prevent up to 4,500 premature deaths.

Under this new standard set to take effect in May, Hamilton County, along with Cuyahoga County, is among four Ohio counties that may exceed this new limit.

Hamilton County’s particle pollution has fallen significantly since 2000, from 18.6 micrograms to 10.5 in 2022. Still, the county has never seen a particle pollution level below the EPA’s new limit of 9 micrograms.

Why is Cincinnati’s air so polluted?

Local industrial plants play a role, but most of the pollution in Cincinnati is due to transportation, according to Joy Landry, spokesperson for Southwest Ohio Air Quality.

“It’s traffic, it’s cars, it’s heavy-duty trucks. It’s 18-wheeler trucks up and down I-75, that are transporting goods along the eastern seaboard,” she said. Interstate 75 causes heavy traffic in Butler and Hamilton Counties, where gas and diesel vehicles contribute to air particle pollution. “That diesel fuel, when it’s burned, often comes out of the stacks on those trucks,” said Landry.

Pollution in Cincinnati can also arrive from out of state, according to Kevin Stewart, Director of Environmental Health for the American Lung Association.

“Upwind sources that contribute to Cincinnati’s air quality may be as near as Louisville or Indianapolis, or as far as western states from which wildfire smoke arrived in Cincinnati last year on the wind,” said Stewart.

Both Landry and Stewart agree that Cincinnati’s air pollution has fallen in large part due to the success of the Clean Air Act of 1990.

“Air quality has actually been improving over the last several decades,” said Landry. “We want to keep moving forward with that good work.”

This article originally appeared on Cincinnati Enquirer: Report ranks Cincinnati among 25 most polluted cities in the US