Facing strong criticism, researchers at Johns Hopkins University, who have put out a number of studies blaming fracking in Pennsylvania for common ailments such as headaches, fatigue, asthma and sinus problems, published a defensive op-ed late last week attempting to justify their work.
Their damage control is partially in response to Energy In Depth's work, which has exposed the flaws in the research team's papers. EID actually dug into the data of their last three health studies and discovered that areas with no drilling showed much higher levels of symptoms than areas with shale development – contrary to the researchers' claims of a link between development and health impacts.
Their asthma study is contradicted by Pennsylvania Department of Health data, which show that heavily drilled counties have far lower rates of asthma hospitalizations than counties that have no shale production at all. The Department of Health data also show asthma hospitalizations declined by 26 percent from 2009 to 2013, when natural gas production in the state soared.
The researchers also claim living closer to shale wells increases the risk of premature birth, but their data show that 11 percent of women had premature deliveries in the area closest to shale wells. According to the Centers for Disease Control and Prevention, roughly 1 in every 9 babies is born prematurely in the United States – or about 11 percent of babies. The rates near wells were not elevated at all, as the researchers tried to suggest.
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In their op-ed, the researchers try to deflect the criticism, claiming that they focused on the individual level, rather than producing an ecological study, which looks at community-wide effects.
Let's consider the individual angle for a moment. If you're trying to figure out whether someone's symptoms were caused by exposure to a particular event, one of your first research tasks is to find out if he or she had those symptoms prior to exposure. Yet in each study, the researchers went out of their way not to include this kind of baseline data.
In their study claiming a link between fracking and sinus problems, migraines and fatigue, the researchers did not even ask the patients if they had migraines or fatigue before shale development. There was no way to tell if they had suffered from these conditions all their lives – as many people do with these conditions – or if the onset was recent. They did obtain some baseline data for sinus problems, but admitted that there were only a "small number of subjects" that occurred after 2006 so they couldn't link those symptoms to fracking.
In their premature birth study, they "excluded births before 2009," so they had no way to tell if rates increased after shale development. They also failed to include data on several other major risk factors associated with preterm births, including smoking, poor nutrition, high blood pressure, diabetes and stress.
Dr. Tony Cox, a clinical professor of biostatistics at the University of Colorado-Boulder, recently penned a letter to the editor in the journal Epidemiology, noting that the researchers' interpretation in the preterm birth study is "unwarranted" and that "claiming that associations provide evidence for a causal conclusion is unjustified."
Dr. Gilbert Ross, senior director of medicine and public health at the American Council on Science and Health, also pointed out, "There is no possible way this retrospective study could have accounted for key issues, such as genetic factors, history of prior pregnancy issues, [or] drug or alcohol use in the parents, all of which have a large influence on birth weights and the duration of pregnancy."
One of the researchers, Dr. Brian Schwartz, is a fellow at the Post Carbon Institute, an anti-fossil fuel advocacy group that has called fracking a "virus." The researchers have attempted to dismiss this criticism because Schwartz is not currently being paid by the Post Carbon Institute, a fact that does nothing to address concerns about his voluntary affiliation with such an organization.
To their credit, the researchers recently wrote that fracking "has been an energy success story." But their willingness to link fracking with a variety of common health issues – even though their data suggest the complete opposite – is why they have attracted significant criticism.
Katie Brown, Ph.D., is the team lead and spokeswoman for Energy In Depth, a research and education program of the Independent Petroleum Association of America.
