U.S. Agriculture Secretary Tom Vilsack speaks during the opening meeting session of the 24th China-U.S. Joint Commission on Commerce and Trade held at Diaoyutai State Guesthouse in Beijing on December 20, 2013. (AFP Photo)

WASHINGTON, March 21 (Xinhua) -- The U.S. Commerce Department on Tuesday set final dumping and subsidy rates on imports of phosphonate, an industrial water treatment chemical, from China, a step closer to impose punitive duties on the chemical in the months ahead.

The department said in a fact sheet that it had finally determined that 1-hydroxyethylidene-1, 1-diphosphonic acid (HEDP) from China had been sold in the U.S. markets at dumping margins ranging from 167.58 percent to 184.01 percent.

The department also set final subsidy rates of 0.75 percent to 54.11 percent for Chinese HEDP producers. HEDP is a phosphonate used in industrial water treatment, household cleaning products, and personal care products.

The department launched anti-dumping and anti-subsidy investigations into imports of the chemical from China in April 2016, in response to a request from U.S. manufacturer Compass Chemical International LLC based in Georgia.

Punitive duties would be imposed after both the Commerce Department and the U.S. International Trade Commission (USITC) make affirmative final rulings. The USITC is scheduled to make its final determination in May.

Imports of HEDP from China were estimated at about 290.1 million U.S. dollars in 2015, according to the department.

The Chinese Ministry of Commerce has kept urging Washington to abide by its commitment against protectionism and help maintain a free, open and just international trade environment.