China's investigation of the tainted milk powder that sickened hundreds of babies widened to its dairy-producing regions on Sunday, as officials attempted to track down the source of melamine in the milk.
One baby died and over 400 developed kidney problems after drinking formula made from milk powder sold by Sanlu Group, one of China's largest milk powder producers that is partly owned by New Zealand's Fonterra Co-operative Group.
Farmers or dealers supplying milk to Sanlu may have diluted it with water and then added melamine, a substance used in plastics, fertilizers and cleaning products, to make the milk's protein level appear higher than it actually was.
Teams traveled to Hebei, Guangdong, Heilongjiang and Inner Mongolia, the biggest dairy-producing regions, to reinforce local governments, ensure dairy inspections were fully carried out, and check milk powder already in circulation, said the General Administration of Quality Supervision, Inspection and Quarantine.
"The teams' primary mission is to underscore the priority the central government has given to the case," said the notice, posted on AQSIQ's website www.aqsiq.gov.cn on Sunday.
A Chinese health official, Gao Qiang, vowed on Saturday to bring food quality supervision to a "new level" after the scandal, which was first reported last week.
Sanlu admitted that its baby formula had been contaminated with melamine, which linked to deaths and illness of thousands of pets in the United States last year after it was added to pet food components exported from China.
It has stopped production of the milk powder and recalled products made before August 6.
In Taiwan, authorities have sealed all Sanlu milk powder products that have yet to be distributed to retailers, after China's Taiwan Affairs Office said Sanlu had exported 25 tonnes of the milk powder to Taiwan in June.
"We've taken all the Sanlu milk powder off the shelves at stores," said Wang Cheng-huei, a deputy director-general of the Bureau of Standards, Metrology and Inspection at Taiwan's economics ministry.
Sanlu had begun receiving customer complaints in March that babies' urine was discolored and that some had been hospitalized, the China Daily said on Saturday.
Many of the sick babies came from poor or remote areas, state media said. Babies in rural China are often raised on formula after their mothers return to work in cities, leaving them in the care of their grandparents. Urban mothers also supplement breast-feeding with formula.
In 2004, at least 13 babies in the eastern province of Anhui died after drinking fake milk powder that investigators found had no nutritional value. The scandal prompted government efforts to strengthen monitoring of food safety.