Study Finds Babies Near Fracking Sites Had Lower Birth Weight

  • A natural gas drilling rig in Washington County, Pennsylvania. Photo: Reid Frazier

June 3, 2015

A new study from researchers at the University of Pittsburgh found that babies of mothers who lived near Marcellus shale gas wells in Pennsylvania had lower birth weights than those born from mothers farther from wells.

The study adds to a small but growing body of scholarship about the potential health impacts of fracking. A University of Colorado study looked at 100,000 birth records in that state and found that babies born from mothers who lived near wells had an increased risk of birth defects. In contrast to the Pennsylvania study, the Colorado researchers actually found an increase in birth weight for infants nearest gas drilling sites.

The Pennsylvania study, published Wednesday in the journal PLOS One, looked at over 15,000 births from Washington, Westmoreland and Butler counties, and included over 500 gas wells drilled from 2007 to 2010. The study grouped mothers by their proximity to drilling and found a difference in birth weight of 21 grams, or about 3/4 of an ounce, between those that lived farthest and nearest to wells.

It also found an increase in the diagnosis of "small for gestational age" for infants from mothers closest to the wells compared to those from farther away.

The authors concede the correlation between proximity to drilling and birth outcomes does not mean that drilling or fracking were the cause. "The low birth weights could be a result of a contaminant related to drilling, an unknown factor "or chance," the authors state.

“It is important to stress that our study does not say that these pollutants caused the lower birth weights,” said co-author Bruce Pitt, in a released statement.

“Our work is a first for our region and supports previous research linking unconventional gas development and adverse health outcomes," the statement continued. "These findings cannot be ignored. There is a clear need for studies in larger populations with better estimates of exposure and more in-depth medical records.”

The industry group Energy in Depth, in a released statement, said the study had a number of 'glaring flaws', noting that there were many factors—like whether a mother spent her whole pregnancy living in the same house—that the scientists didn't account for. 

"Low birth weight can result from genetics, outside influences, premature birth, the mother’s decisions—and the list goes on," the statement said. "Studies such as this one, which simply don’t have the science to back up their claims, are paraded as credible research, causing undue concern for pregnant women."

In a response, the authors released a statement of their own: "Our study used contemporary statistical approaches ...that was peer reviewed by scientific experts and that led us to the carefully described conclusions as stated in the manuscript."

Anecdotes of health impacts, such as nose bleeds, headaches and skin lesions, have accompanied the fracking boom in the U.S. But scientists have thus far been unable to prove any link between drilling and medical problems for people who live near wells. More than 9,000 wells have been drilled in Pennsylvania in the past decade in the Marcellus Shale, the country's number one producing natural gas formation.

Pennsylvania Governor Tom Wolf has budgeted $100,000 to create a shale health registry, which would track health complaints in areas of gas development.  

A bill before the state senate would create a nine-member panel to examine shale health impacts.

The University of Pittsburgh study was funded by the Heinz Endowments. The Allegheny Front also receives funding from the Heinz Endowments.