Living near fracking sites during pregnancy may increase the risk of adverse birth outcomes, according to a new study in the journal JAMA Pediatrics. After analyzing data from around 35,000 pregnancies over a six-year period, the study authors detected an association between proximity to fracking wells and outcomes such as congenital defects and preterm births. Fracking – or hydraulic fracturing – is a controversial process that involves blasting shale gas deposits with huge volumes of water via horizontally-dug wells. The technique has led to environmental concerns due to its potential to trigger earthquakes, while the World Health Organization classifies the association between fracking and human health as “mostly unknown.” The study authors looked at all pregnancies in rural Alberta, Canada, between January 1, 2013, and December 31, 2018. People were considered to be exposed to fracking if their postal address was within ten kilometers (6.2) miles of one or more wells that were hydraulicly fractured in the year prior to conception or during pregnancy. After adjusting for risk factors such as maternal age, multiple births, obstetric comorbidities, and socioeconomic status, the researchers found that pregnant people who lived near fracking sites were significantly more likely to have babies that were small for gestational age or display major congenital anomalies. The risk of spontaneous preterm delivery, meanwhile, was significantly increased for pregnancies within ten kilometers of 100 or more wells. While the risk of these adverse outcomes was heightened with exposure to fracking during both the preconception period and pregnancy, no such association was seen for exposure during only one of these two critical time periods. Explaining these findings, the authors write that “together, these results suggest that the association of hydraulic fracturing is not in proximity but in the density of operations in a given area and the cumulative amount of exposure an individual may have.” Though this study did not seek to illuminate the mechanisms by which fracking may impact pregnancy, the authors do propose several possible pathways. For example, they explain that while the procedure involves the use of thousands of chemicals, toxicity information is lacking for all but 240 of these. Of those 240, 103 are linked to reproductive toxicity, which means that “pregnant individuals may be especially susceptible to hydraulic fracturing exposure that occurs during critical stages of gestation.” Alarmingly, separate studies have revealed that some of these substances can be detected in the hair and urine of pregnant people living close to fracking sites. The study authors also point out that fracking requires the transport of huge amounts of water, most of which is delivered via heavy trucks. This, they say, may lead to an increase in local air pollution, which could negatively impact the health of pregnant people and their unborn babies. Highlighting the significance of this contamination, study author Amy Metcalfe told Healio that “there's a large body of evidence linking, essentially, primarily air pollution and other forms of pollution to adverse pregnancy outcomes, with a clear association between air pollution and spontaneous preterm birth.” It’s important to note, however, that this study does not provide evidence of a causal link between fracking and adverse birth outcomes. Having said that, the findings of this large-scale investigation certainly provide cause for alarm, and highlight the need for more research into the impact of hydraulic fracturing on human health. Source
