Pregnant women living next to fracked gas wells are more likely to have a low birth-weight baby - that's the finding in a new study from Princeton University.
The researchers compared standard birth-weight records collected by Pennsylvania hospitals with the locations of the parents' homes. Princeton economics professor and study co-author Janet Currie said they found a strong correlation - that the low birth weights were highly localized, much more likely to be found right next to the well sites.
"What is surprising is we found a fairly large effect for people living very close" Currie said; "but by the time you got to two miles away, we did not detect any effect."
The industry argues that air pollution from gas wells and equipment such as compressor stations disperses quickly after it's released. It also says the issue is well understood and regulated.
Low birth weight has long been considered an important indicator of later health problems.
Currie said based on previous research, they think the problem may be due to volatile organic compounds such as benzene, or small, soot-like particles like those found in diesel exhaust.
Beth Weinberger, public health consultant with the Environmental Health Project, said these kinds of dangerous air pollutants are well documented as common in the gas fields. And she said previous research has associated them with preterm births and similar issues.
"We know much of what's in the emissions," Weinberger said; "and in each of the studies, the researchers have found associations between exposure to gas drilling and birth outcomes."
The Princeton research recommends drilling be kept away from homes, through zoning or well set-back rules. Weinberger added that even a portable air filter may help some homes reduce pollution levels.