Memphis Smog Levels Raise Health Concerns

The American Lung Association said on April 21 that Shelby County got an F for ozone pollution, and metro Memphis rose to the 27th-worst ranking in the country. (lung.org) The group’s 2026 “State of the Air” report measured 9.8 unhealthy ozone days a year in the Memphis area, using data from 2022 through 2024. (lung.org) That moved Memphis up from 32nd-worst a year earlier and marked the third straight year of worsening ozone conditions in Shelby County. (lung.org) Ground-level ozone is smog made when pollution from vehicles, power plants, and industrial sites reacts in sunlight. The Environmental Protection Agency says it can inflame airways and make breathing harder, especially for people with asthma or emphysema. (epa.gov) (tennesseelookout.com) Shelby County’s health department runs 27 monitors at five sites and tracks ozone, particulate matter, nitrogen dioxide, sulfur dioxide, and other pollutants year-round. It added a Photochemical Assessment Monitoring Station in 2021 to meet federal requirements tied to the 8-hour ozone standard. (shelbytnhealth.com) (tn.gov) Environmental groups escalated the fight last June, when the Southern Environmental Law Center asked the Environmental Protection Agency to declare the Memphis metro area out of compliance with the 2015 ozone standard. (tennesseelookout.com) (localmemphis.com) That petition said ozone averages had exceeded federal limits for two straight years and that four of five Memphis-area monitors were over the health standard. Shelby County officials said they had ongoing ozone-reduction projects, including electric-vehicle replacements and bicycle-commuting programs. (tennesseelookout.com) (mlk50.com) Pollution concerns in South Memphis have also centered on xAI’s data center, where Politico reported in May 2025 that 35 methane gas turbines were operating without pollution controls. Environmental groups estimated the turbines could emit 1,200 to 2,000 tons of nitrogen oxides a year. (politico.com) AirNow’s real-time readings can still show “good” or “moderate” days in Memphis, because daily conditions change with heat, wind, and sunlight. The annual grade reflects several years of monitor data, not a single afternoon’s forecast. (airnow.gov) (lung.org) For Memphis residents, the latest warning is not about one smoke-filled day. It is about a metro area whose ozone record has worsened for three years while regulators, industry, and environmental groups argue over how fast to cut emissions. (lung.org) (tennesseelookout.com)