Hydraulic fracturing, or “fracking,” may pose a significant—but very local—harm to human health, a new study finds. Mothers who live within two miles of a fracking well are more likely to give birth to a child with a low birthweight—which has been linked to poorer health throughout a person’s life.
The research, published Wednesday in Science Advances, is one of the largest studies done thus far on fracking’s health effects. The authors took the birth records for every child born in Pennsylvania from 2004 to 2013—more than 1.1 million infants in total—and looked at their mother’s proximity to a fracking site, using the state of Pennsylvania’s public inventory of fracking well locations.
The study was conducted by Janet Currie, an economist at Princeton University, Michael Greenstone at the University of Chicago and Katherine Meckel at the University of California, Los Angeles.
Birthweight is a straightforward measurement—it is listed on every baby’s birth certificate—but a low birthweight can affect the path of someone’s life. Children with a low birthweight have been found to have lower test scores, lower lifetime earnings, and higher rates of reliance on welfare programs throughout their lives. In one study, researchers examined twins in Norway whose birthweight diverged by 10 percent or more. The lighter twin was 1 percent less likely to graduate high school and earned 1 percent less than their sibling.
The birthweight of children is affected by many other variables, such as socioeconomic status. But those factors mean that the study may undercount the risk that fracking poses to unborn children. Pregnant mothers living within a half-mile of a fracking well may benefit financially from its presence, diluting the negative health effects of the well itself.
The economists caution that the study may undercount the risk that fracking poses to unborn children, as pregnant mothers living within a half-mile of a fracking well may benefit financially from its presence. The birthweight study seems to suggest that air, not water, pollution may instead be the threat that fracking sites pose to human health.