The latest scandal was first exposed in a research report from a website on Monday, renewing public concern about food safety. A probe into the distilled spirits market has found trace amounts of DEHP, mainly DBP, in liquor products.

Most experts believe liquor producers do not deliberately add plasticizers to their products, which may well be tainted via plastic containers or tubes in their storage or transport.

Distilled spirits, or "baijiu" in Chinese, have been popular among different communities in China. Amid fast-growing economy in recent years, the liquor industry has grown, with its sales revenue reaching around 400 billion yuan (63.5 billion U.S.dollars) last year.

The liquor scandal will deal a blow to the competitive industry. Sales of some liquor products have dropped in the wake of the scandal, which has not yet fully shown its scope.

In fact, the China Alcoholic Drinks Association knew that liquor products contained plasticizers in June last year and urged liquor companies to trace the sources of plasticizers. Later, it asked liquor companies to ban the use of plastic products in production, storage and transport.

Shortly after plasticizers were detected in hundreds of local products in Taiwan in May 2011, the Chinese mainland authorities were alerted to the contamination. In June 2011, the national food safety committee issued a notice on strengthening the quality safety of liquor products.

This was the latest in a string of food contamination scandals, which has included melamine-tainted milk, pork containing the illegal additive clenbuterol and pharmaceutical capsules with excessive levels of chromium, over the past five years.

One of the most notorious food scandals involved melamine-tainted milk powder in 2008, which killed at least six babies and sickened 300,000 others. A number of officials were removed from their posts, members of the Sanlu management were jailed and Sanlu Group, once a leading dairy producer in China, went bankrupt.

Official data show that the law enforcement dealt with more than 180,000 food and medicine safety cases and penalized nearly 40,000 people in such cases between November 2007 and February 2012.

In February 2011, amendments to the Criminal Law imposed harsher punishment on offenders in food safety crimes and inspection officials guilty of negligence.

The recent liquor scandal has underlined the urgent need for effective quality control measures on the part of responsible enterprises and active inspection efforts on the part of the government.