The battle for clean air in South Memphis continues.

On Tuesday, the Southern Environmental Law Center sent a letter to the Shelby County Health Department.

The group is demanding officials to force Sterilization Services of Tennessee to reduce toxic emissions or shut down the facility altogether.

The sterilization plant has been using a gas called ethylene oxide to clean medical equipment in South Memphis since the 1970s.

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The Environmental Protection Agency has learned the gas is 60 times more toxic than originally thought and causes an increased risk for several cancers.

“We breathe in toxic, day in and day out,” Ora Edwards, of South Memphis, said.

Edwards said the polluted air has sickened her family and her neighbors. “It has made a lot of people sick around here, but most people stay inside,” she said.

The EPA says they are working on new guidelines to limit exposure but community members say they want action to be taken now.

“The facility has been operating for a long time. People are being exposed to toxic emissions on an ongoing basis. With the new information that has come to light, the time to act is now,” Amanda Garica, with the Southern Environmental Law Center, said.

Garcia said the prominent environmental group sent the letter to Shelby County health officer Dr. Bruce Randolph on behalf of the group Memphis Community Against Pollution.

It urges the health department to use its emergency powers to shut down the plant or force it to stop using ethylene oxide.

“Their emergency authority is designed exactly for this type of situation where a facility may be in compliance with its permits but it’s still causing an emergency situation that is threatening people’s health,” Garcia said.

Garcia said they have not yet gotten a response from the health department.

The department told FOX13 it will continue to hold meetings with residents to ensure they understand health risks and will update the Shelby County Commission on the status of any new EPA regulations on March 8.