What's being called one of the most comprehensive groundwater studies ever done in the U.S. was published Wednesday, and, according to the lead scientist, some of its findings are "incredibly alarming."

The tests were performed over the past two years in the Barnett Shale and purport to show a growing link between fracking and groundwater contamination.

The study is published in the trade journal Environmental Science and Technology. Dr. Zac Hildenbrand, one of the lead authors of the study who collaborated with the University of Texas at Arlington, collected samples from 550 water wells in 13 counties along the Barnett Shale.

LINK: An evaluation of water quality in private drinking water wells near natural gas extraction sites in the Barnett Shale formation

Samples were collected throughout Montague, Wise, Parker, Hood, Tarrant, Somervell, Johnson, Hill, Ellis, Dallas, Denton, Collin and Cooke counties during 2013 and 2014. The results show water contaminated with "multiple volatile organic carbon compounds throughout the region, including various alcohols, the BTEX family of compounds and several chlorinated compounds."

Dr. Hildenbrand told News 8 by phone Wednesday that all of the chemicals are associated with the fracking industry.

"When you find a BTEX compound with a chlorinated compound with an anti-corrosive agent all in the same water well, it's pretty shocking evidence that there's been a problem," said Hildenbrand. "The only industry that uses all of those simultaneously is the oil and gas industry."

The study is quick to point out that it does not establish fracking as a source of contamination, but it does provide a strong association.

"The conclusion we can make is where there is more drilling there is more abnormalities in the water," Hildenbrand said.

Oil and gas industry advocates, Energy in Depth, responded to the study on Thursday.

"The authors specifically say that they cannot link contamination to unconventional oil and gas activity. Activist groups and some media are trying to manufacture a fracking link that the data don't definitively support," Dave Quast with Energy In Depth said.

Sharon Wilson, a North Texas environmentalist with Earthworks, said regardless of what's to blame, the test results make it clear that using well water in the Barnett Shale is now proven to be potentially dangerous.

"It's going to absorb into your skin, it's going to come out in steam from the water when you take a shower," said Wilson "When your hair is wet and you blow-dry your hair you are going to breathe that steam. So no, you need to not use your water."

News 8 has already done a series of stories on alarming levels of methane contamination of water wells in Parker County. The oil and gas industry has already denied there is any conclusive link and says the methane in Parker County is naturally occurring.

MORE: From News 8 Investigates