Goverment health experts are investigating a possible cancer-causing additive in oil used to cook KFC products.

The move comes after some KFC outlets in Shaanxi Province were found to be using a suspected carcinogenic additive to filter and recycle old frying oil.

However, the restaurant chain's parent company Yum China said in a press release that the additive had been approved by the country as a safe additive in food manufacturing as well as being accepted by the U.S. Food and Drug Administration for filtering used frying oil. It said all KFC restaurants in China had used the additive since 1999, and all recycled frying oil met national standards.

While the municipal health authorities were not reachable for comment yesterday, dozens of Shenzhen Daily readers voiced their concerns over the potential health risk.

"My 7-year-old son has often eaten KFC's fried chicken wings over the past four years," said one mother in front of a KFC outlet in Huaqiangbei. She believed it was common sense for food manufacturers not to recycle frying oil, and KFC was risking consumers' health if the additive was proved to be carcinogenic.

The suspect additive, said to be Magnesium Trisilicate by the restaurant, is used as a kind of absorbent to filter unwanted residue from used frying oil. Chinese media reported that it enables KFC to recycle oil up to 10 days old.

The additive's manufacturer, U.S. chemical company Dallas Group, claimed the product could help maintain frying oil's quality by absorbing fatty acids and removing impurities which form in edible oils during the frying process.

"Recycled frying oil contains various carcinogens such as Benzypyrene, and these can't be reduced by additives," said a surgeon surnamed Li from the city's Beijing University Shenzhen Hospital.

The additive "scandal" was first reported in Xi'an, Shaanxi Province, on Thursday, and soon hit headlines in China's influential newspapers and on Web sites.

Local health authorities in Shaanxi Province seized and halted the use of the suspect additive.

KFC said the reports were inconsistent with the facts, and would consider legal action.

Editor: Donald