It's not a chicken-and-egg situation, though.

The Centre for Food Safety (CFS) yesterday found that one chicken egg sample from Hunan Province had contained Sudan dye, a cancer-causing substance the mainland has found in some duck eggs earlier.

The centre had collected the sample from Sun Sun egg shop at Cheung Sha Wan wholesale market. The shop had imported the eggs from the mainland.

Secretary for Health, Welfare and Food York Chow said the government would ban the egg import from Hunan but added that the products would not be taken off the markets as the health risks are minimal.

Chow also said that the government was considering legislation requiring the importers to show health certificates.

Meanwhile, the test results on the duck eggs originated from Hubei Shendan Healthy Food Co Ltd and sold at a fair organized by Yue Hwa Chinese Products Emporium Ltd, showed that one egg sample had contained 0.035mg per 1,000 grams Sudan red.

Chief Executive Donald Tsang yesterday urged health officials to pay extra efforts to address the food safety concern of the public.

Tsang's comment came after York Chow apologized to the public for making confusing statement on the eggs.

"I hope the departments concerned will learn a lesson from the recent incident to improve the food safety mechanism and strengthen the effective operation of the Centre for Food Safety (CFS)," he said.

The health chief admitted that communications within government departments must be improved.

Chow's apology

"I apologize that I wasn't able to give you the full picture of what's happened (on Tuesday)," Chow said.

Chow criticized the centre for making wrong judgment and not being fully alert. "Since the brand of eggs have already been exposed, I think it is reasonable that we should inform the public about the availability of such thing in Hong Kong," he said.

Health officials were criticized for giving false information on Monday and Tuesday that the contaminated eggs by Shendan Healthy Food had not been sold in Hong Kong.

However, it was later revealed that Yue Hwa Chinese Products Emporium had informed the Centre for Food Safety last Friday that they had sold 1,000 duck eggs produced by Shendan Healthy Food Company Ltd at a food fair.

Some 1,400 eggs from the same batch had been sold out, and the remaining 2,000 returned to the centre.

The CFS acting controller Ho Yuk-yin explained that it did not inform the public of the Yue Hwa's stock on Monday press briefing because they were not from the same batch with the contaminated products on the mainland.

"With the benefit of hindsight, we should improve communication with the public," Ho said.

"The decision of not disclosing to the public about Yue Hwa's stock earlier was made without careful consideration," he said.

The officials, however, stressed that communication with the State Administration of Quality Supervision, Inspection and Quarantine was adequate.

The health officials urged the public not to panic, and advised them not to eat the eggs if they have abnormal colouring.

Meanwhile, the misgivings on mainland eggs have intensified among the public. An egg vendor in the Causeway Bay Market, Chan Siu-cheng, said there had been a 20 per cent drop in egg sales in the last two days.

"My regular customers know I get my stocks from US and Holland, but others shy away," he said.

A local resident of Tin Hau, Mrs Siu, a 42-year-old housewife, said she would refrain from buying eggs for her family.

In an apparent attempt to boost business, some egg vendors in Tin Wan Market have put up signs of countries of origin of their egg products. "My businesses have dropped significantly," said Ms Hui, a 49-year-old egg vendor. "There've been customers asking me where I get my stock, so I thought I'd just put up the signs for everyone to see," she added.

Legislative Council food safety and environmental hygiene panel would convene a special meeting next Thursday to discuss the problem.