Shanghai KFC Co Ltd said that paper containers for its "family barrels" meet national standards in terms of fluorescent brightener, National Business Daily (NBD) reported.

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The company cited a report provided by the National Environmental products Quality Inspection Center on March 23.

NBD reported the International Food Packaging Association has started investigating this issue.

A reporter based in Guangzhou took samples of paper cups from seven random brands from a supermarket, and a "family barrel" paper container and a Coca-Cola cup from KFC. The reporter sent the samples to the Food Engineering department at South China University of Technology. The primary results showed that only two paper cups meet standards.