Researchers gained more insight into the contents involved in the process of the gas and drilling technique called hydraulic fracturing, "fracking."
The findings raise concerns about several of the fluid's ingredients. Of the nearly 200 compounds commonly used in the mixture eight are toxic to mammals and very little is known about the potential health risks imposed by one-third, the American Chemical Society reported.
Fracking involves injecting water and a mixture of chemical additives into rock formations deep below the Earth's surface to release gas and oil. The process has led to an industrial gas boom but many are concerned it pollutes well water and increases pollution at the sites.
"The industrial side was saying, 'We're just using food additives, basically making ice cream here,'" William Stringfellow, Ph.D. said. "On the other side, there's talk about the injection of thousands of toxic chemicals. As scientists, we looked at the debate and asked, 'What's the real story?'"
Researchers at the Lawrence Berkeley National Laboratory and University of the Pacific looked at databases and reports to compile a list of substances commonly used in fracking. The team included "gelling agents to thicken the fluids, biocides to keep microbes from growing, sand to prop open tiny cracks in the rocks and compounds to prevent pipe corrosion," the Society reported.
The team found while tracking fluids do contain plenty of non-toxic and food grade materials, but some of these may not be as safe and easily disposable as they sound.
"You can't take a truckload of ice cream and dump it down the storm drain," Stringfellow said, referring to the industry's analogy. "Even ice cream manufacturers have to treat dairy wastes, which are natural and biodegradable. They must break them down rather than releasing them directly into the environment."
The team determined most fracking materials would require treatment before being released, and eight compounds were found to be toxic to mammals.
"There are a number of chemicals, like corrosion inhibitors and biocides in particular, that are being used in reasonably high concentrations that potentially could have adverse effects," Stringfellow said. "Biocides, for example, are designed to kill bacteria - it's not a benign material."
Researchers were able to find vert little information of the toxic qualities of one-third of the compounds used in fracking.
"It should be a priority to try to close that data gap," Stringfellow said.
The findings were presented at the 248th National Meeting & Exposition of the American Chemical Society (ACS).
