BEIJING, Dec. 1 (Xinhua) -- A sample test has identified the carcinogenic red dye, Sudan IV, in eggs in Beijing, according to the municipal food safety office.

    The office organized a comprehensive examination of hen and duck eggs sold in Beijing after 1,159 kilograms of red-yolk salted duck eggs containing the dye were seized in November.

    One of the 56 samples was found to contain the dye.

    The eggs, which have been taken off shelves, were produced by the Shendan Health Food Co. Ltd., in the central province of Hubei.

    Sudan dyes are used legally in the leather and fabric industries, but are banned for food use. Last year, the Ministry of Agriculture reiterated the ban after the dyes were found in some brands of pepper sauce, chili oil and KFC's New Orleans roast chicken wings.

    China's food safety watchdog announced on November 21 that it had discovered seven companies producing salted red-yolk eggs contaminated with the dangerous red Sudan dyes.

    The companies were in Beijing and the provinces of Hebei, Anhui,Henan, Zhejiang and Hubei, said the State Administration of Quality Supervision, Inspection and Quarantine in a statement.