According to the latest World Health Organization (WHO) guideline, the tolerable daily intake (TDI) standard for melamine has been set at 0.2 milligrams per kilogram of body weight. WHO's Director of Food Safety Jurgen Schlundt said, "We expect this will better guide the authorities in protecting the health of the public."

The new limits of TDI which were released in Ottawa, Canada, on Saturday were lower than previous limits suggested by some countries' food safety authorities. The WHO said based on this standard a person weighting 50kg can tolerate 10mg of melamine per day.

Melamine is a toxic industrial chemical that may cause kidney stones and other kidney disease and this is the first time that the WHO has announced tolerable limits for it. “Melamine is a contaminant that should not be in food. However, sometimes it is unavoidable,” said international experts.

In October after the melamine-contaminated milk food scandal the government set a limit of 1 mg a kg for infant milk food and 2.5 mg a kg for other dairy products. Yang Jianhong, a member of Dairy Association of China, said the TDI "is scientific because it gives a tolerable level based on people's body weight". The US Food and Drug Administration (FDA) in October said that though 2.5 mg of melamine in 1 kg of milk product would not cause any problems, baby milk food exported to the US must not have any melamine. They changed the acceptable levels to 1 mg in 1 kg, which was the same limit that had been set by China after traces of melamine were reportedly found in the infant formula of a major US company and a related chemical, cyanuric acid, was detected in another big firm's product.

Chen Junshi, a senior researcher with the National Institute for Nutrition and Food Safety said: "WHO's daily limit is a guideline for all countries to control their melamine standards. It means normal people can consume up to 10 mg melamine a day without any harmful effects. It also means the country's existing limit is safe," he said.

In Taiwan under current standards baby formula, milk powder and creamers must test negative for melamine when screened by highly sensitive liquid chromatography/tandem mass (LC/MS/MS) spectrometers that can detect the presence of as little as 0.05 parts per million of melamine in a substance. The Department of Health (DOH) has not established a TDI for Taiwan and said it would take these limits and would consider Taiwanese eating habits before setting a level.

“The WHO’s suggestion [of a melamine TDI] is important for us. But to set up a TDI in Taiwan, we need to take into consideration the eating habits of Taiwanese ... and the quantity of food consumption,” DOH spokesman Wang Je-chau said.