"Two top U.S. natural gas producers called on the industry to release data about the chemicals they use in the fast-growing Marcellus shale development to counter fears it was polluting water supplies.

The Marcellus, which stretches from West Virginia across most of Pennsylvania and into New York, could hold a 10-year supply of natural gas for the United States, but its development is sparking a backlash from some residents who say they are at risk."

Matt Daily reports for Reuters September 24, 2009. [2]