An outbreak

When China launched its national school milk program, nine ministries and bureaus established a coordination group, which is affiliated with the Ministry of Agriculture.

School milk carries special symbols on its packaging and cannot be sold in the marketplace. Authorized enterprises must pass expert evaluation and approval of the coordination group. The price of school milk must be lower than the market price of similar products in the same region.

"Direct delivery was compulsive, and the service was regulated," Wang Dingmian, former vice-chairman of the Guangdong Provincial Dairy Association, told China Daily on Monday. "But when the management system ended in 2003 and the administration and approval rights were passed on to local departments below the provincial level, problems began to erupt."

The incident with the widest impact happened in Haicheng, Liaoning province, in March 2003. A total of 3,936 students and 260 teachers in eight primary schools showed symptoms after drinking soymilk at school. A 13-year-old girl died.

An investigation found that the food poisoning was caused by the soy flour, the raw material used in soymilk.

Five years later, 152 children in several kindergartens in Zhuhai and Jiangmen, Guangdong province, were poisoned when they drank milk processed by Zhuhai Bigshot Dairy Co. The company did not meet the qualifications for supplying school milk but had long been a major supplier for local schools.

The Ministry of Health reported, "The milk was contaminated by a kind of coccus (bacterium) in the process of adding ingredients, and was not effectively disinfected."

Five incidents occurred in April 2010 in Shaanxi province. In two cases, investigations showed that the milk from Mengniu Dairy Group and another dairy giant, Yili Industrial Group, met national standards for food safety.

Shaanxi Renrengao Dairy, a private company based in Baoji, was the culprit in two of the cases. Its filling machines did not seal milk packages well, so air sneaked in and the milk spoiled.

The company had acquired a license for manufacturing of industrial products, a food hygiene license and ISO9001 quality management accreditation.

No reports were found about how the enterprises were punished. Bigshot and Renrengao have multiple product lines today.

In the fifth case, nine pupils at Qianwei town's Andai Primary School in Lantian county suffered abdominal pain after ingesting milk and eggs at school. No reports about the culprit were found.