China is investigating a complaint that South Korean producers are selling pure and polymeric M-D-I on the Chinese market below the cost of production. M-D-I is a chemical used in the production of artificial leather, elastic fiber and glue. The Ministry of Foreign Trade And Economic Cooperation made the announcement Friday, but didn't provide details, including the length of the anti-dumping investigation. Japanese exporters are also under investigation. China's State Economic and Trade Commission, a ministry which oversees the country's state sector industries, will carry out a separate inquiry into any damage caused to the domestic industry by alleged dumping.