Some Chinese toothpaste has been found to contain a toxic chemical

The government published a five-year plan late on Tuesday to increase inspections and tests on exported food.

Singapore has become the latest country to take action against Chinese toothpaste imports found to contain a chemical contained in anti-freeze.

The chemical, diethylene glycol, has been blamed for the deaths of at least 50 people in Panama last year.

"Monitoring and administering food and pharmaceutical safety must be at the very heart of grassroots and base work," according to a document published on a government website on Tuesday.

"Food safety is not only a problem related to law enforcement, but also related to the people's health and safety, the country's image, and also bilateral and multilateral political relationships," said Li Changjiang, the head of China's main food safety agency.

In the future "illegal activities behind production and sale of fake and shoddy foods and pharmaceuticals will be effectively contained," the five-year plan says.

Mr Li, and his deputy Wei Chuanzhong, called for better safety testing, and for those who ignore safety regulations to be punished.

Potentially deadly

Singapore has banned three brands of toothpaste imported from China, after tests showed they contained diethylene glycol.

The city state's health authority found that the Hei Mei, Hei Mei Calcium and Maxam brands contained between 0.8% and 3.9% of the chemical, and ordered the items off the shelves.

US officials have already warned consumers to avoid using toothpaste made in China. On Thursday Nicaraguan health authorities seized 40,000 tubes of Chinese-made toothpaste after they were found to contain diethylene glycol (DEG).

The Dominican Republic, Panama and Costa Rica have already removed thousands of tubes of toothpaste from store shelves.

In addition to being used as a coolant, DEG is sometimes used as a low-cost but potentially deadly substitute for glycerine sweetener commonly used in medicines.

It was found in the cough syrup and other medicines blamed for last year's deaths in Panama.

US inspectors have also blamed exported Chinese pet food ingredients, contaminated with melamine, for the deaths of cats and dogs in North America.

Thirteen babies also died of malnutrition in China in 2005, after being fed powdered milk that contained no nutritional value.