EPA says metro Phoenix ozone pollution has gotten worse

By Pratham Dalal
Published: Friday, September 23, 2022 - 2:28pm
Updated: Friday, September 23, 2022 - 4:42pm
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The EPA has reclassified Maricopa County to a more severe status for ozone pollution, moving the region from “marginal” up to a label of “moderate.”

In 2015, the EPA reduced its ozone pollution guidelines from 75 particles of pollution per billion to 70. Counties had until 2021 to hit the updated guidelines and Maricopa County failed to do so. Maricopa County is the eighth-worst county for particle pollution, according to a report from the American Lung Association.

According to JoAnna Strother of the American Lung Association, the physical features in Arizona pose a challenge to reduce ozone.

"We have weather inversions. Some of the cooler air gets trapped with warmer air on top here in the valley, specifically so Ozone tends to stick around for longer days," she said. 

Strother says ozone forms when sunlight hits directly against harmful chemicals emitted in the air. Fuel from cars is a big polluter of these chemicals, according to the EPA. Strother says electrifying vehicles like the city of Phoenix is in progress of doing with their Transportation Electrification Plan will be a big help.

Strother says it is important to act now, before it's too late, “We have to act now before this gets to a place where we are really causing human harm. Again, vulnerable populations: children, pregnant woman, seniors, but again any healthy person can have symptoms from breathing in pollution.”

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