Almost 90 percent of food inspected in the first half of the year passed safety tests, Shanghai Food and Drug Administrative Bureau (SFDA) said yesterday.

However traces of heavy metals and chemicals as well as bacteria remain a major problem, according to a food safety report issued by the SFDA yesterday.

The report was based on tests of more than 12,000 food samples taken in the city's food markets and restaurants in the first six months.

The report showed a slight improvement on last year: Qualified food rate was 89.3 percent, up 2.8 percent.

The inspection covered 17 types of food such as lunch boxes, dairy products, meat, processed food and vegetables among others.

But experts warned that additives were overused by some producers with the aim of extending the shelf life or improving the appearance of the food. Additives are widely used in flour, pickled foods or bean products.

Food inspectors also found heavy metal, chemical residues and bacteria to be the major additives in meat and fish. "These additives account for 75 percent of the total in the food we tested," said an SFDA official surnamed Xu.

Regarding the increasing number of food poisoning cases caused by bacteria, SFDA will add two new types of dangerous bacteria to guidelines for restaurants: listeria and E.coli O157.

"Up till now, no residents have been reported to have been poisoned by such dangerous bacteria. But we have already detected them in food many times," said Li Jie, vice director of the city's Food and Drug Inspection Institute.

Food officials suggest residents refrain from eating raw or half-cooked foods like beef.

(China Daily August 9, 2006)