The number of Chinese children ill from toxic milk formula may have nearly doubled since the Health Ministry's last public count, local media reports show, but an official said Wednesday the number of new cases is falling.

Beijing is struggling with fallout from adulteration of milk with the industrial chemical melamine.

Four babies died and thousands of infants fell sick in China, while around the world products made with Chinese milk have been recalled.

The government also announced new dairy safety standards Wednesday, setting limits on the use of melamine, a cheap industrial chemical that can be used to cheat quality checks.

China has not updated official figures issued Sept. 21, when it said 12,892 infants were in hospital, 104 with serious illness, and close to 40,000 others were affected but did not need major treatment.

But reports from local media across the country compiled by Reuters suggest the number of affected children has risen to nearly 94,000, although most are not in a serious condition.

In some areas, diagnoses rocketed up in just a few days. In the most extreme case, northwestern Gansu province, the number of sick children climbed to 13,459 by Sept. 26 from 1,695 a week earlier, the official Xinhua agency said.

Worst hit so far is central Henan province, with over 30,000 cases by the end of September. Neighbouring Hebei also has nearly 16,000 cases.

The province is home to Sanlu Dairy group, which made the contaminated formula that sparked the broader scandal.

Despite the rash of cases across the country — few areas appear to have been entirely immune — the government says it has the problem under control and recent checks have found no trace of melamine, the toxic additive, in liquid milk.

The number of sick children appearing at hospitals is also falling after news of the problem blanketed domestic media and spread across the internet, prompting parents to take extra care about what they feed their children.

"The daily reports of infants who were diagnosed and hospitalized are decreasing noticeably," said Chen Junshi, a researcher at the Institute of Nutrition and Food Safety at the Chinese Centre for Disease Control and Prevention.

But he declined to say how many had been ill overall.

"I'm not authorized to publish the number of sick infants," he added at a news conference held by the Health Ministry.

Even if the pace of new diagnoses is slowing, there is still room for a major leap in the total number of affected children because some of the country's most densely populated cities and provinces, like Shanghai, have not disclosed any figures.

New standards

Public worries about tainted milk have subsided in the past two weeks as China was transfixed by the country's first space walk and then enjoyed the week-long National Day holiday.

But as part of an ongoing effort to restore confidence in the "made in China" brand, the government on Wednesday also released new dairy safety standards, setting limits on the use of melamine.

The new limits set by the Ministry of Health are one milligram of melamine per kilogram for infant formula, 2.5 milligrams per kg for liquid milk, milk powder and food products containing at least 15 per cent milk.

The U.S. Food and Drug Administration said earlier this month that no amount of melamine is safe in baby formula, but China said it has set levels low enough to protect its people's health.

"There is probably a little amount of melamine in the environment, " Wang Xuening, deputy director of the Health Ministry's Health Supervision Bureau, told the conference.

"So we couldn't set zero levels, " he said, adding that melamine content below the new limit is definitely not a threat to human health. Wang said the limits mainly aim to curb deliberate use of the chemical as an additive.

Hebei province has already arrested 27 people suspected of involvement in contaminating milk with melamine. Sanlu group's chairwoman Tian Wenhua was also detained last month.

With files from Reuters