Living near an active hydraulic fracturing site is associated with a heightened risk of being hospitalized for cancer, cardiovascular conditions and neurological problems, a new study finds, providing even more evidence that fracking likely poses significant health risks to those living near drilling wells.
Researchers from the University of Pennsylvania and Columbia University analyzed data from more than 198,000 hospitalizations to investigate the link between drilling well density and health care use in three northeastern Pennsylvania counties. The analysis, which focused on the years 2007 to 2011, found that zip codes with higher fracking density also had higher rates of hospitalization.
The researchers published their findings this week in the journal PLoS ONE.
“This study represents one of the most comprehensive to date to link health effects with hydraulic fracturing,” said senior author Dr. Reynold Panettieri, a professor of medicine and deputy director of the Center of Excellence in Environmental Toxicology (CEET) at Penn’s Perelman School of Medicine
“At this point,” he said, “we suspect that residents are exposed to many toxicants, noise and social stressors due to hydraulic fracturing near their homes and this may add to the increased number of hospitalizations.”
Hospitalization rates up 27 percent in areas with more drilling activity
Recent changes in fracking activity gave the researchers an opportunity to design a natural experiment to look at the link between drilling well density and nearby hospitalization rates. As you can see in the chart below, the number of zip codes with no fracking wells was cut in half between 2007 and 2011, while the number of zip codes characterized by a high density of fracking wells spiked during the same time period.
Two of the counties examined — Bradford and Susquehanna — had a significant increase in drilling activity during the study period. Wayne County, used as a natural control, had no drilling activity since a ban on drilling was enacted due to its proximity to the Delaware River watershed.
The results of the analysis revealed that cardiology and neurologic inpatient prevalence rates — expressed as the proportion of a population hospitalized among every 100 residents each year — were significantly higher in areas closer to active wells.
Compared with Wayne County, where there is no drilling, the 18 zip codes with high well density (greater than 0.79 wells per square kilometer) saw a 27 percent rise in cardiology inpatient prevalence rates. This finding held true even after accounting for historical hospitalization rates and a number of other potential confounding variables.
Furthermore, the researchers found that living near active wells was also associated with higher hospitalization rates for skin conditions, cancer, and urologic problems.
“We posit that larger numbers of active hydraulic fracturing wells would increase inpatient prevalence rates over time due in part to increases in potential toxicant exposure and stress responses in residents evoked by increases in the hydraulic fracturing work force and diesel engine use,” the study concludes.
Unraveling the health effects of fracking
It’s important to point out that although the study found statistically significant associations with hospitalization, this link cannot prove that hydraulic fracturing is causally related to any health problems.
However, the results do point to a potentially under-studied problem, and the researchers say further investigation is needed to look at the effects of specific, individual toxicants and combinations of toxicants that may account for the increase in hospitalization rates.
The rise in cardiology hospitalizations, for example, could be related to diesel exhaust and fine particulate matter — both of which are released into the air in large quantities around fracking sites — but personal monitoring studies will be needed to measure exposure to specific toxicants. Dr. Panettieri says the team’s findings will help “provide important clues to design epidemiological studies to associate specific toxicant exposures with health end-points.”
The authors also note that the rise in hospitalization rates over the relatively short study-period highlights the need to factor in health care costs in calculations of the potential economic benefits of fracking.
This study is just the latest in a growing line of evidence linking fracking activities to a range of health hazards. Just last month, an analysis of Pennsylvania birth records revealed that women living in close proximity to drilling sites are significantly more likely to deliver low birthweight babies. And a study published in May found that people living closest to fracking sites have a 45 percent greater risk of developing cancer than those who live farther away.
According to a 2014 assessment by the National Resources Defense Center, the major health risks associated with fracking include respiratory problems, birth defects, blood disorders, cancer and nervous system impacts. More recent research has also identified a high risk for endocrine- and hormone-related disorders from chemicals used during the fracking process.