A new study has found that drinking water from shale gas extraction is more contaminated than that coming from drinking water sources.

Researchers from the University of Michigan found that chemicals emitted by drilling for shale gas and hydraulic fracturing — also known as fracking — are less contaminated when it comes to water contamination than drinking water coming from surface sources.

The researchers, led by University of California, Berkeley, professor and former U.S. Geological Survey geochemist Joseph M. Hecht, conducted the research with University of North Carolina’s Dr. David Sargent and the National Institute for Occupational Safety and Health (NIOSH).

The findings were published in the journal Environmental Science & Technology.

The study examined water samples collected in the Marcellus Shale, a natural gas-bearing formation located in southeastern Pennsylvania.

They analyzed the levels of a dozen chemicals, including benzene, ethylbenzene, benzocarbene, and methanol.

The team compared the levels with water samples from the same area of the same drilling site.

The results showed that water samples coming from the Marcels shale was about 70 percent more contaminated compared to drinking water.

That’s because water coming directly from the shale contains higher levels of benzene and ethylbutene, which is known to be more contaminated by fracking fluids.

The authors also noted that water from wells drilled for shale is contaminated by chemicals emitted from the fracking process.

These chemicals can be released as the fracking fluid is being heated, and then can react with other chemicals in the water to produce more contaminants, the researchers wrote.

These chemicals include ethyl benzene (EBZ), benzocarbon, methanolic, and acetonitrile, which can be found in water used to treat wastewater.

Researchers are now working to understand how fracking fluids and chemicals affect water and how they are transported in the environment.

The new research could be used to inform regulations governing drilling and fracking operations, and to help determine the best way to reduce water contamination in areas where fracking is taking place, the scientists wrote.

Dr. Heicht, who was a visiting research associate at the University at Buffalo, has been working with the U. S. Geological Service since 2012.

He is a member of the National Academy of Sciences, the National Academies of Sciences and Engineering, the American Academy of Arts and Sciences, and the Society for Environmental Medicine.

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