A four-month nationwide campaign will begin on Wednesday to ensure all food products are free of non-edible substances and excessive levels of additives, the government said on Monday.

The move comes after melamine-contaminated baby milk food caused the death of six infants and left about 290,000 with urinary tract ailments, including kidney stones.

The government is also working on a compensation package for the tainted milk victims, an official said.

"The tainted-milk scandal shows illegal production of food products and the use of non-food substances are not isolated incidents. Instead, they are quite typical of the industry," Vice-Minister of Health Chen Xiaohong said during a national teleconference in Beijing.

"If these problems are not solved, food scares are likely to recur."

The campaign, to be jointly conducted by nine central government departments, is aimed at cleansing and regulating the market, Chen said, and firms using excessive food additives will be hauled up.

The Ministry of Health said the campaign would be divided into three phases:

From tomorrow to Jan 10, companies will be asked to conduct self-examination and correction.

From January 11 to March 10, law enforcement officers will raid high-risk food producers or regions, and intensify random checks on markets.

From March 11 to April 10, the focus will be on illegal food-additive producers and cutting off the supply of high-risk non-food substances.

Meat, dairy, brewery and other products rich in protein are high-risk food products, Pu Changcheng, deputy director of the General Administration of Quality Supervision, Inspection and Quarantine (AQSIQ), said at the conference.

Illegal substances found in food products such as Sudan Red and Malachite Green are considered high-risk substances and demand special attention during checks.

"But quality control officials should pay attention to new illegal substances appearing in food products, too, and submit timely reports. Recurrence of cases like the melamine contamination must be prevented," Pu said.