The Chinese news agency Xinhua says the People's Daily newspaper have both carried reports suggesting that the addition of industrial chemical melamine to animal feed in China is an open secret. Quentin Sommerville reports from Beijing.

　　 Animal feed in China is routinely contaminated with industrial chemical melamine, according to the country's state media. Chemical firms have been repackaging scrapped melamine as protein powder and selling at home. When added to the feed, it gives the illusion of boosting nutritional levels. China's melamine scandal began in the dairy industry, 4 babies died and 20 thousand children were hospitalised after the chemical was added to milk. This week, the authorities in Hong Kong discovered melamine in 4 brands of Chinese produced eggs. It's believed they have got there because of contaminated animal feed.