The discovery of excessive levels of the industrial chemical melamine in Chinese eggs has prompted Hong Kong authorities to expand food testing to include meat products imported from China, a senior official said Sunday.

The move follows the announcement late Saturday that Hong Kong testers had found 4.7 parts per million of melamine in imported eggs produced by a division of China's Dalian Hanwei Enterprise Group. The legal limit for melamine in foodstuffs in Hong Kong is 2.5 ppm.

Hong Kong Food and Health Secretary York Chow said the melamine might have come from feed given to the chickens that laid the eggs.

"The preliminary opinion experts have given us is that there is a problem with the feed," Chow told reporters Saturday.

The egg results have prompted officials to expand food testing to all meat imports from China, Chow told reporters Sunday. He said Hong Kong officials will step up checks of eggs imported from China. Calls to Dalian Hanwei Enterprise Group, based in the northeastern port city Dalian, went unanswered Sunday.

In an egg-related food safety scare in Hong Kong and China in 2006, the banned cancer-causing industrial dye Sudan Red was used to color egg yolks.

3,600 children sickened by tainted milk

China is caught in a food safety scandal over dairy products tainted with melamine. More than 3,600 children remain sick in China from contaminated milk, with three in serious condition, the Health Ministry said last week. The deaths of four infants have been blamed on dairy products contaminated with melamine.

Authorities say dairy suppliers apparently added melamine to milk they collected from farmers to sell to large dairy companies. The suppliers are accused of watering down the milk and then adding the nitrogen-rich chemical to make the milk seem higher in protein when tested.

Melamine is used in the manufacture of plastics, fertilizer, paint and adhesives. Health experts say ingesting a small amount poses no danger, but in larger doses, the chemical can cause kidney stones and lead to kidney failure. Infants are particularly vulnerable.

The Hong Kong government also said it found excessive amounts of melamine in Blueberry Cream Sandwich crackers made by Philippine company Croley Foods Mfg. Corp.