BEIJING, Aug. 21 -- The Chinese Ministry of Commerce has imposed an anti-dumping duty of 49.8 percent on Indian companies after they were found to have dumped Tertiary Butylhydroquinone (TBHQ) products in the Chinese market.

The anti-dumping duties on the TBHQ imports from India will begin Friday and last five years, the ministry ruled on Thursday.

TBHQ can be used as antioxidant in cooking oil or as additives in the pharmaceutical and animal feed industries.

The ministry's final ruling came four months after it launched temporary anti-dumping measures against such imports from India.

According to the ministry's one-year investigations, TBHQ imports from India have been dumped in the Chinese market and such imports have caused substantial damage to China's domestic industry.

However, the anti-dumping duties will not be retroactive to imports before April 30 this year, according to the ministry.