Daily Record Business Writer//April 8, 2015
//Daily Record Business Writer
//April 8, 2015
The increasing use of hydraulic fracturing to extract natural gas in Pennsylvania over the past decade has been accompanied by an increase in levels of radon gas, according to a new study.
But the study’s leader says it’s not clear that the drilling method, known as fracking, has caused the increased levels of the naturally-occurring radioactive gas, which has been shown to increase the risk of lung cancer.
Researchers from the Johns Hopkins University Bloomberg School of Public Health examined nearly 2 million radon measurements taken across Pennsylvania between 1987 and 2013, and compared the figures from before and after fracking began in 2005.
Counties where there is now more hydraulic fracturing, or fracking, showed a relative increase in radon levels since 2005 compared with counties with less or no drilling, according to the study.
Between 2005 and 2013, 7,469 natural gas wells were drilled in Pennsylvania using fracking, which uses water to extract natural gas from underground shale.
The study did not conclude there was a causal link between fracking and higher radon levels, said Dr. Brian S. Schwartz, a professor of environmental health sciences at the Bloomberg School.
Another possible explanation for the increase is that buildings may have been sealed more tightly over the past ten years to increase energy efficiency, Schwartz said. If that’s the case, then more radon may have been trapped in the buildings, leading to higher measurements when there’s been no overall increase of the gas, he said.
However, Schwartz said he didn’t know if there had actually been such a change in how building were sealed.
Historically high levels
Pennsylvania was ideal for the study because the state has historically had high levels of radon and there was a large amount of radon testing data to draw from, Schwartz said.
And while a recent study by the state of 34 individual natural gas wells did not show high levels of radon, Schwartz said the Bloomberg School’s study showed a potential cumulative effect of all the wells in the state.
Lawmakers continue to debate whether to allow fracking in areas of western Maryland that also lie on the Marcellus Shale, which runs beneath a large section of Pennsylvania.
Even if fracking is eventually allowed in Maryland, Schwartz said the state is unlikely to encounter the same scope of potential risks that Pennsylvania has.
“I don’t think Maryland is ever going to have that many wells,” he said.l