BEIJING -- China's food and drug regulator has ordered a ban on eight products manufactured by four mainland-based companies over fears that their products may have been contaminated by an industrial chemical.

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In a circular issued Saturday, the State Food and Drug Administration asked catering firms to stop purchasing or using the banned products, which are believed to have been contaminated with DEHP, an organic compound that may cause hormonal malfunctions and other health problems in people who consume the chemical in high doses.

Among the products listed are a guava flavoring additive made by Guangzhou Meiyi Flavors & Fragrances Co Ltd; green tea powder, liquid butter oil and egg milk-flavored oil produced by Jiangmen Goody's Food Co Ltd and a bread yeast improver produced by Jiangmen Jhan Wang Food Co Ltd, all of which are based in south China's Guangdong Province.

The other three banned products are osmanthus, green tea and almond flavoring additives produced by a food additive manufacturer based in the city of Hangzhou in east China's Zhejiang Province.