EPA Region 4 includes Alabama, Florida, Georgia, Kentucky, Mississippi, North Carolina, South Carolina, Tennessee and six tribal nations.
The announcement came Tuesday from EPA Administrator Gina McCarthy.
Toney, a lawyer, was the first black and first female mayor of Greenville and served from 2004-2012. In 2012, she tried unsuccessfully to unseat U.S. Rep. Bennie Thompson in Mississippi's 2nd Congressional District.
Since then, Toney has practiced law and as an advocate for education, women's issues, health and wellness issues.
Regional administrators manage the EPA's regional activities. They promote state and local environmental protection efforts and serve as a liaison to government officials.
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