KEVIN BEGOS, Associated Press
MATTHEW DALY, Associated Press

PITTSBURGH (AP) — 

The U.S. Department of Energy is welcoming the decision by oil and gas industry supplier Baker Hughes to disclose all chemicals in hydraulic fracturing fluid. But Halliburton, a major competitor in the field, isn't committing to such disclosure.

Deputy Assistant Energy Secretary Paula Gant says Friday that the move by Baker Hughes "is an important step in building public confidence."

Environmental groups and regulators say a loophole that allows companies to hide some chemicals in frack fluids is a problem.

Houston-based Halliburton says it's studying the move by Baker Hughes, which is also based in that city. Halliburton says it had an interest in protecting "our intellectual property and the substantial investment it represents" and will examine the new Baker Hughes format for its ability to protect such investments.

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