by Andy Tully
Two academic studies of the health dangers of hydraulic fracturing, or fracking, have produced different conclusions.
One, conducted by Yale University, said people living near fracking sites report increased health problems. The other, by Penn State University, says fracking water stays underground, far below the groundwater supplies that people use for drinking, and poses no threat.
Both studies were conducted in Pennsylvania, part of the Marcellus Shale formation in the sprawling Appalachian Basin in the eastern United States. It holds enormous reserves of gas and has been a focus of fracking activity and protests.
In the Yale study, former Yale medical professor Dr. Peter Rabinowitz reported in the journal Environmental Health Perspectives that residents living near a fracking site in southwestern Pennsylvania were more than twice as likely to report skin problems and respiratory illnesses than those living farther away.
Rabinowitz, now at Pennsylvania’s University of Washington, surveyed 492 people in 180 households in Washington County, PA -- the heart of the Marcellus Shale. Thirty-nine percent of respondents living within 0.6 of a mile of a gas well reported sinus infections and nosebleeds, compared with 18 percent who said the same and lived more than twice as far away.
The difference was even starker for those reporting skin problems: Thirteen percent reported rashes, while only 3 percent of people who lived farther away had the same complaints.
Rabinowitz said his is “the largest study to date” of its kind. But he cautioned that he isn’t directly linking fracking to the health problems. To determine that will require more research, he said, because “it’s more of an association than a causation.”
The Penn State study concluded that the water and chemicals that are injected into deep shale to help extract gas stays far below the surface and therefore doesn’t pose a serious threat to drinking water supplies.
The study, whose results were published in the Journal of Unconventional Oil and Gas Resources, was conducted by Terry Engelder, professor of geosciences at Penn State; Lawrence Cathles, professor of earth and atmospheric sciences at Cornell University; and Taras Bryndzia, a geologist at Shell International Exploration and Production, Inc.
Opponents of fracking say the contaminated water used to help extract the gas could seep toward the surface and foul clean groundwater. The Penn State study says this isn’t likely because the water would seep up too slowly, if it seeped at all.
Further, it says, upward migration of tainted water isn’t plausible because of the forces used to inject the water into the shale. “As water is wicked into gas shale, the natural gas in the shale is pushed out, Engelder says. “The capillary forces that suck the [water] into the gas shale keep it there.”
The debate continues.