In Wuhan and Beijing, four baby girls started growing breasts after drinking baby formula made by a leading infant formula company, the South China Morning Post reported. The babies, aged from four to 15 months, started growing breasts after drinking baby formula made by Synutra, based in Qingdao. This has prompted the Ministry of Health to order the food safety authority in Hubei to launch a probe. 'The ministry has demanded that the Hubei food safety supervision task force investigate and relevant authorities conduct laboratory tests on samples from the brand,' said Ministry of Health spokesman Deng Haihua. Medical tests indicated the hormone levels in the three Wuhan babies exceeded those of the average adult woman. Local food safety authorities had earlier refused a parent's request to investigate the formula, saying they did not conduct tests for consumers. In Guangzhou, many hospitals have stopped supplying Synutra to newborns at parents' requests. Synutra said its products were safe and that no man-made hormones or illegal substances had been added during production. It said it 'welcomes consumers and the media to visit our plants for an inspection'. Wang Shuhuai, a researcher from the China Institute of Veterinary Drug Control, said a standard for traces of hormones in dairy products has yet to be released. In 2008, Chinese dairy products were recalled worldwide after it was found that melamine, which is used to make plastics, was added to raw milk to get past protein tests. At least six children died from kidney failure and 300,000 others suffered from kidney stones. Despite repeated pledges by the authorities to crack down on the toxic milk powder, it is a problem that keeps resurfacing. Seventy-six tonnes of tainted milk powder produced from Qinghai were seized last year while hundreds of tonnes of stored toxic milk powder were discovered in February. Some of it was used to make diary products like milk candy.