Beijing, April 21 (IANS) Infant food products, in which the quantity of melamine is higher than one milligram per kilogram of food, will be prohibited from sale in China, according to an official regulation.

Melamine is a toxic chemical used in manufacturing plastics.

In other food products, the maximum tolerable level of melamine would be 2.5 mg per kg of food, Xinhua reported citing the regulation issued by the health ministry.

"Melamine, neither a kind of food material or food additive, is prohibited from being intentionally added into food," said the regulation, which took effect Wednesday.

Anyone who adds melamine to food on purpose would be dealt with according to the law, it said.

However, the regulation also noted that very low levels of melamine may enter the food chain naturally from the environment or through product package materials.

Ingestion of melamine over a period of time can cause damage to urinary and reproductive systems, lead to kidney stones and bladder cancer.

In 2008, China's food industry suffered a heavy blow when milk products were found to contain dangerously high levels of melamine, which were intentionally added to make milk appear to be protein-rich.

The toxic milk killed at least six babies and caused sickness in over 300,000 across the country.