An official source reports that the Centre for Food Safety found 4.7ppm of melamine in those eggs. The legal limit for melamine in food is 2.5ppm.

To exceed the tolerable amount, the center said a child weighing 10kg would have to eat about 12 of these eggs a day, and an adult of 60kg to eat 144 of the eggs per day.

Speaking in a radio programme yesterday, Controller of Centre for Food Safety, Constance Chan, said the government is going to broaden its food safety program to cover more food items, including eggs and meats.

"By including more food items in the food test, we hope to make people feel safe about the food they eat," she explained.

Peter Wong, president of World Poultry Science Association Hong Kong Branch, said he is pleased with the government's move.

Melamine in farm feeds could be passed from chicken to eggs, he said.

As melamine was found in many foods, he noted that there could be an accumulated impact on human health.

He said the egg exporter in Dalian has always made their own feeds and it is unnecessary for them to add melamine to the feeds to increase the protein level.

"I'm worried that the problem [of adding melamine to feeds] could be quite common on the mainland," he said, adding it is possible that more tainted eggs could be found.

He said mainland authorities should ban the use of melamine in farm feeds immediately.

Meanwhile, PARKnSHOP said it has already taken all contaminated eggs off shelves.

The supermarket chain has also started voluntarily to recall Best Buy brown eggs which are imported from Dalian. Customers can get a full refund upon presentation of the items and receipt.

Meanwhile, buying and selling of eggs at the Western Wholesale Food Market was normal yesterday morning.

The Hong Kong Egg Merchants Association (Fung Kwai Tong) stressed that eggs imported from the mainland recently have passed inspection by mainland authorities and it is safe to eat eggs from the mainland.