More than 20,000 century eggs ripened with toxic chemical were seized in Nanchang, capital city of east China's Jiangxi province on Wednesday, June 13. June 15 - More than 20,000 century eggs processed with toxic chemicals were seized on Wednesday by staffs from a quality watchdog in Nanchang, capital of east China's Jiangxi province.The illegal products were manufactured by an egg processing factory located in Qianwan village of the city, the Jiangnan City Daily reported.While inspecting the factory, the quality watchdog officials found industrial sodium hydroxide, which can cause cancer if eaten, was used to quicken the pace of the eggs' maturity. All the products steeped in some 70 huge barrels were immediately seized.Century eggs, also known as preserved eggs or hundred-year eggs, are a popular traditional Chinese food. It is usually cut into slices or tiny cubes and made into dishes such as tofu with century egg or century egg congee, a type of porridge made of rice.The forthcoming Dragon Boat Festival, which this year falls on June 19, usually results in a sales peak of egg products.