The first research into the effects of oil and gas development on babies born near wells has found potential health risks.
However, government officials, industry advocates and the researchers themselves say more studies are needed before drawing conclusions.
Bloomberg newsagency reports while the findings are still preliminary, any documented hazards threaten to cast a shadow over hydraulic fracturing, or ‘fracking’, the process of blasting chemicals, sand and water deep underground to extract fuel from rock that’s helped push the United States closer to energy self-sufficiency than at any time since 1985.
“It’s not really well understood how the environment interacts with genetics to produce these birth defects,” said Dr Lisa McKenzie of the Colorado School of Public Health, who conducted research published in January in the journal Environmental Health Perspectives.
“We really need to do more study to see what the association is, if any, with natural gas development.”
Dr McKenzie and her colleagues discovered more congenital heart defects in babies born to mothers living near gas wells in Colorado.
Two studies, which have not been peer reviewed, showed infants born near ‘fracking’ sites in Pennsylvania were more likely to have low birth weight, a sign of developmental problems.
In Utah, local authorities are investigating a spate of stillbirths after tests found dangerous levels of air pollution from the oil and gas industry.
“The question isn’t are there risks, the question is are there rules and regulations in place that effectively mitigate these risks and deal with problems should they occur, and the answer is yes,” said Steve Everley, a spokesman for Washington-based Energy In Depth, an industry-funded group that promotes ‘fracking’.
“The body of scientific knowledge has to advance gradually and you have to look at all of these things and the full spectrum.
“You can’t just look at this one individual or this group of studies,” he said.
In published research, Dr McKenzie and her colleagues found that babies born to mothers living with more than 125 wells within 1.6km of their homes showed a 30 per cent increase in congenital heart defects compared with those with no wells within 16km.
The abnormalities, based on 59 available cases in Colorado, ranged in severity and could have resulted from genes or environmental causes other than fossil-fuel extraction, according to Dr McKenzie.
The study was not conclusive because it did not account for different types of wells, water quality, mothers’ behaviour or genetics, the Colorado Department of Public Health and Environment said in an e-mailed statement to Bloomberg.
Dr McKenzie said she’s starting another four-year study, funded by the American Heart Association, which focuses on a subset of the cases to determine their precise exposures to pollutants and other risk factors, such as the parents’ occupations.
“I think it’s up to each individual to look at the data and make their own decision on whether or not they’re concerned,” Dr McKenzie said.
“The data do tell us with more wells in the area there are more congenital heart defects, although there are a lot of limitations in the data and when we start looking at it more closely, that may or may not stand up.”
Bloomberg reports a separate investigation into 22 anomalies in unborn children in Garfield County, Colorado, in 2013 found no underlying cause after examining factors including proximity to active oil and gas wells, the state’s public health department said in May.
The county has more than 2000 oil and gas wells, according to FracFocus.org, an industry-sponsored website.
Kathleen Sgamma, a spokeswoman for the Western Energy Alliance, an industry group whose members include Anadarko Petroleum and Pioneer Natural Resources, said exploration and production companies are funding more research on health effects and are working to reduce emissions by installing equipment and adjusting practices.
Bloomberg reports two Pennsylvania studies, however, found increases in low birth weight near gas drilling, but they have not been published in peer-reviewed journals.
Infants born within 2.5 kilometres of ‘fracking’ sites were about 60 per cent more likely to have low birth weight, according to a review of Pennsylvania birth records from 2004 to 2011 by researchers from Princeton University, Columbia University and the Massachusetts Institute of Technology.
The study was presented at the annual meeting of the American Economic Association in January.
That research echoed a December working paper by Elaine Hill, then an economics graduate student at Cornell University in New York, which found that babies born to mothers living within 2.5 kilometres of a gas well during pregnancy had lower average birth weights after drilling than before.
The results were consistent between piped public water and well water, suggesting the exposure came from air pollution or stress, Ms Hill said in the paper.
Low birth weight leads to higher health-care expenses and greater likelihood of needing special education, amounting to a total cost to society of about $96,500 a child, according to the paper.
Previous research has shown a link between air pollution and low birth weight in general, Ms Hill said in the study.
