A new study by Canadian researchers has reported links between adverse pregnancy outcomes and living near fracking sites.
What is fracking?
Hydraulic fracturing, or fracking, is an unconventional method for extracting fossil fuels, such as oil and gas, from underground rock. The technique involves drilling deep wells and using a mixture of water, sand and chemicals to generate high pressures that create fractures in the rock, through which oil and gas can escape to be harvested.
In Australia, fracking has been controversial for some time and has recently been back under the spotlight due to plans to frack for natural gas in the Northern Territory’s Beetaloo Basin and for oil in the Kimberley in Western Australia. The proposal to frack in the Beetaloo Basin is currently the subject of a Senate inquiry.
Proponents of fracking plans point to expected economic benefits. But experts have repeatedly raised concerns about the effect of continuing fossil fuel exploration and development on Australia’s ability to meet targets to reduce carbon emissions and avoid catastrophic climate change. Opponents have cited further concerns about water contamination, the potential to trigger earthquakes, and damage to Indigenous cultural sites and practices. The health risks of fracking are also an area of active research.
Read more: What does science say about fracking?
What did the new study find?
The new Canadian study examined data collected between 2013 and 2018 from more than 34,000 pregnancies in rural areas of the province of Alberta.
The researchers found a significantly higher incidence of congenital anomalies (adjusted risk ratio of 1.31) and babies who were small for their gestational age (adjusted risk ratio of 1.12) born to mothers who lived within 10 kilometres of at least one fracking well. These results were supported after adjusting for several other factors, including parental age, multiple births, foetal sex, obstetric comorbidities, and the socioeconomic status of the area where the family lived.
For those living in areas within 10km of 100 or more fracking wells, the risk of spontaneous preterm birth was also significantly elevated (adjusted risk ratio of 1.64).
The authors wrote that previous studies from the United States had found associations between proximity to fracking sites during pregnancy, and increases in preterm birth and low birth weight.
While the study design could not determine whether the adverse pregnancy outcomes were directly caused by fracking, the research team proposed several potential mechanisms that could explain the relationship. These included groundwater contamination and changes in air quality due to fracking, as well as reproductive toxicity of chemicals present in the fracking fluids that are pumped underground.
“This study from Alberta, Canada, raises some potentially very important concerns about the possible environmental risks for women who live close to fracking sites,” says David Ellwood, a professor of obstetrics and gynaecology at Australia’s Griffith University, who was not involved in the study.
“The increased risk for babies of major congenital anomalies, and being small for gestational age, suggests an effect in pregnancy that is there from the outset and may be mediated through placental function.
“With larger numbers it is possible that other effects could be seen which are mediated via placental dysfunction such as stillbirth.”
Are there any implications for fracking proposals in Australia?
Alex Polyakov, an associate professor in medicine at the University of Melbourne, cautioned that the results may have limited application to Australian contexts.
“The risk of adverse outcomes was only significantly elevated for women who were exposed to a large number of fracking sites for significant periods of time,” says Polyakov.
“In Australia, fracking is not nearly as widespread as it appears to be in Canada. Most fracking shafts are also situated in sparsely populated locations, and it would be highly unusual to find multiple fracking sites in close proximity to residential areas, even in the rural setting.”
However, it doesn’t follow that these risks should be taken any less seriously, particularly when the population at risk already experiences health disparities. For example, the area around the Beetaloo Basin is home to several towns and communities with a large Indigenous population.
“Given the seriousness of these findings, it is important to try and replicate this work in other settings,” says Ellwood.