Alabama Agriculture and Industries Commissioner Ron Sparks on Wednesday extended a two-year-old order banning the sale of untested fish from Vietnam and China in Alabama.

Sparks said Wednesday the new order comes after catfish from China and basa from Vietnam tested positive for fluoroquinolones, an antibiotic used in humans, but not approved for fish. Basa is a fish that tastes similar to catfish and is found in southeast Asia.

Sparks said his department's labs found the substance after testing fish from China and Vietnam that were marked as having already been tested. He said fish from the two countries can still be sold in Alabama, but only if they have been tested. Even then, Sparks said Alabama officials are allowed to order their own tests.

"We're going to stop it and it will never make it to dinner plates in Alabama," Sparks said of fish that tests positive for the antibiotics. "Personally I would not eat it. I would not recommend it."

Department of Agriculture chemist Joe Basile said the danger to humans eating fish containing the substance is that people might build up an amount of fluoroquinolones in their systems and allow bacteria to build up a tolerance to the antibiotic.

The antibiotic was also found in a small amount of fish imported from Cambodia, Indonesia and Thailand. The order banning sales was not immediately extended to those countries.