Parents vent anger, frustration over poisoning of children Holding her 10-month son in her arms at a Beijing children's hospital, Zhao Shuping cries as she tells how angry and shocked she is to learn the milk powder her son has been drinking could kill him. 'I couldn't fall asleep last night,' Mrs Zhao said. 'I feel so bad for having fed my baby toxic milk since the day he was born. Living on the mainland, we sort of know that our food is always contaminated, but doing this to a vulnerable baby? The greedy businessmen are shameless.' Mrs Zhao was just one of the parents who flooded hospitals yesterday to have their children checked after revelations a far greater number of the mainland's dairy product manufacturers than first thought were putting the chemical melamine into some of their goods. At the Capital Institute of Paediatrics, one of Beijing's two children's hospitals, parents arrived as early as 3am. Queues formed quickly, and by late afternoon the soonest a parent could have their child given an ultrasound was a week away. Crowded around at the hospital, mothers poured out their anger and frustration. Some talked about how they could feed their children and decided that only foreign brands were safe. One mother said they had to look for specific batch numbers of a foreign brand because they were manufactured as well as packaged overseas. Another asked two nurses which brand was safe, but they only gave her an apologetic look and said 'no idea'. Mrs Zhao and her husband rushed to the hospital before 4am and were fortunate enough to have their son scheduled for an ultrasound that day, but she said she still worried. 'The tests for the first couple of babies took around 20 minutes, and as more and more babies came, they sped up the process. 'We were there for only three minutes. I'm not completely sure and will have him checked again at another hospital,' she said. Another young couple, who had their six-month-old son checked by a doctor but would have to wait a week for an ultrasound, blamed the dairy companies and the government. 'Those companies were awful and should take responsibility. But where were the government agencies before babies were killed by the toxic milk? If they had done their job, we would not be here,' said the father, 29, who gave his name only as Mr Xiao. He said the inspection authorities could have done more. With tests focused only on melamine, he wondered what in the milk powder was going undetected. 'What if other toxic additives that we don't know about have been added? What about other dairy products? And what about other food? I don't think the government learned any lessons from the Fuyang scandal,' Mr Xiao said, referring to a 2004 tragedy that caused 13 baby deaths in a fake milk powder scandal in Anhui . More than 200 babies suffered wasted limbs and swollen heads - symptoms of malnutrition. More than 50 officials were disciplined or told to stand down and dozens of manufacturers were ordered to close in the aftermath. The Shanghai Children's Hospital, which has opened a special clinic with free medical checks for children believed to have been affected by milk powder from state-owned manufacturer Sanlu, was also crowded with worried parents. Zhang Chaoyang , 35, a migrant worker from Jiangsu province , said he was shocked to find his eight-month-old baby who drank Sanlu formula from birth had kidney stones. 'My baby was sick in June. He had a serious stomach ache and diarrhoea, but the doctor said he might have eaten something bad. So I didn't suspect the milk powder problem until I watched the news several days ago,' Mr Zhang said. 'Now my baby has diarrhoea at least three times a day, and we cannot sleep at night because he is always crying.'