BEIJING (AP) -- The parents of a 1-year-old boy who developed kidney stones after drinking infant formula tainted with an industrial chemical are suing the dairy at the heart of the scandal, state media reported, as tests implicated 15 more companies Wednesday.
The case is believed to be the first civil lawsuit filed in response to the contamination of milk, yogurt and other dairy products with melamine, which causes kidney stones and can lead to kidney failure. Nearly 54,000 children have been sickened and four infants have died.
According to the lawsuit, the boy was fed baby formula made by Sanlu Group Co. from the time of his birth, said the report by Caijing, a leading Chinese business magazine.
The child's parents, who come from central China's Henan province, filed a lawsuit in a court in Zhenping county seeking $22,000 in compensation from Sanlu for medical, travel and other expenses incurred after the child developed kidney stones, the magazine said.
The Zhenping court has yet to accept the case, said the report, which gave the parent's surname, Sun, but did not give their full names or that of their child.
The lawsuit comes amid increasing public awareness of an individual's legal rights in China. Some parents who lost their children when shoddily built schools collapsed in a massive earthquake in May reportedly tried to sue local governments, but were offered cash in return for signing pledges not to sue.
Jerome Cohen, a Chinese legal system expert and a professor at New York University School of Law, said it was surprising the couple was even able to file a lawsuit.
"That itself is news," Cohen said. "Lawyers are not being permitted generally to help people bring about such suits. Sometimes, though, the system is porous and they don't have uniform rules. Sometimes lawyers just take a chance."
Cohen said that courts in China have not been handling such cases so "it will be interesting to see if this goes forward."
The case is being represented by Ji Cheng, a lawyer from the Beijing office of Deheng Law Firm, the report said. Ji has gathered evidence that included empty packets of Sanlu milk powder the child consumed and medical treatment reports from health care facilities in Henan.
Ji said his clients sought legal help because they could no longer afford medical treatment for their child, the report said.
Even though China's State Council, the Cabinet, has ordered hospitals to provide free health care for sick children, the facility where this child was being treated, Beijing Children's Hospital, only offers free treatment to children diagnosed after Sept. 12, when the scandal broke, the magazine said.
It said Ji's clients have had to foot all medical expenses incurred since June, when the baby started showing symptoms.
Calls to the law firm rang unanswered Wednesday, a national holiday in China.
China's government, meanwhile, named 15 more dairy companies found to have products contaminated with melamine after a new series of tests. The tainted samples were mostly milk powder products for adults.
Thirty-one samples of Chinese milk powder provided by 20 companies were found to contain melamine, according to data seen Wednesday on China's food safety administration's Web site. The 20 included five companies already implicated in the scandal. Product safety officials could not be reached for comment.
Twenty-seven people have been arrested in connection with the contamination. The scandal was worsened by the way Sanlu reacted to the affair. State media reported the company ignored warnings as early as last December from parents and doctors that babies were being sickened. Top Sanlu executives and government officials in the northern city of Shijiazhuang, where the company is based, have been forced to resign.
Melamine, which is high in nitrogen, is used to make plastics and fertilizers and experts say some amount of the chemical can be transferred from the environment during food processing.
But in China's case, suppliers trying to boost output are believed to have watered-down their milk, adding melamine because its nitrogen content can fool tests aimed at verifying protein content.
Levels of melamine discovered in batches tested varied widely, from as much as 6,196 parts per million to as little 1.3 parts per million. Chinese health officials have said no harm comes from consuming less than 0.63 parts per million.
In the most recent tests, nine of the batches containing melamine were produced by Sanlu. No date for the testing was given.
Associated Press Writer Carley Petesch in New York contributed to this report.