Lessons learned from the past, if not forgotten, can serve as a guide for the future. But this motto does not seem to work with the food safety supervision and management department, which has failed repeatedly to block some contaminated or even poisonous food from being put on supermarket shelves.

The salted duck eggs that have been found to contain a poisonous red dye for industrial use in Beijing's supermarkets this week is the second case of this dye being put into food in China. And it is one of a string of similar cases involving food that's been artificially contaminated in recent years.

A case of this type will never serve as a guide for the future unless its root cause is found and those responsible for the entire process from the making to the selling are punished accordingly.

Those raising ducks in Beijing's neighbouring Hebei Province add the poisonous red dye to the feed in order to make the yolks of their duck eggs look nice.

The fact that they never eat the eggs themselves proves they know what they are doing.

These eggs are bought by local plants that process them into salted ones before selling them to supermarkets or restaurants in the province and its neighbouring cities. It is still unknown whether these plants test the eggs before buying them, but the eggs were sold to supermarkets in Beijing with food testing reports attesting to their safety and quality.

Beijing's food safety supervision and management department is supposed to be responsible for blocking unsafe food from entering markets in the capital. The fact that the poisonous duck eggs were found in Beijing's supermarkets shows the negligence of the department.

It is strange that the discovery of the same poisonous eggs in the neighbouring city of Tianjin last year did not alert the relevant departments and the supermarkets in Beijing.

The smooth travel of the poisonous duck eggs through various checkpoints to the dining tables of Beijingers indicates that the controls are too loose and there are too many loopholes in food safety supervision and management.

The immediate action taken by the capital and Hebei Province to seal all packages of the problematic eggs is far from enough to ease public panic.

What is worse is that frequent similar occurrences will shake public confidence in the food safety supervision and management department.

We hope that sealing and destroying all of the problematic duck eggs will not be the end of the story. And we can only expect this case to serve as a deterrent to those rule violators and as a warning to those who neglect their duties as long as the producers, providers, testers and departments involved are given due penalties.

(China Daily November 15, 2006)