Children living near unconventional oil and gas (UOG) or ‘fracking’ developments at birth had a 2–3 times greater risk of leukaemia diagnoses between 2 and 7 years old, researchers have found.
Their study, published in the journal Environmental Health Perspectives, included nearly 2500 Pennsylvania children, 405 of whom were diagnosed with acute lymphoblastic leukaemia (ALL).
ALL arises from mutations to lymphoid immune cells. Although long-term survival rates are high, survivors may have long-term health risks and psychological issues. Unconventional oil and gas development, more commonly referred to as fracking (short for hydraulic fracturing), is a method for extracting gas and oil from shale rock. The process involves high-pressure injection of water, sand, and chemicals into bedrock to release oil or gas for extraction.
For communities living nearby, UOG development can pose a number of potential threats. As well as air pollution from vehicles and construction, there is also water pollution from hydraulic fracturing or spills of wastewater. Hundreds of chemicals have been reportedly used in UOG injection water or detected in wastewater, some of which are known or suspected carcinogens. The lack of data about this has given rise to concerns over the proximity of UOG to residential areas.
“Unconventional oil and gas development can both use and release chemicals that have been linked to cancer, so the potential for children living near UOG to be exposed to these chemical carcinogens is a major public health concern,” said the study’s senior author, Nicole Deziel, associate professor of epidemiology at the Yale School of Public Health.
“Studies of UOG exposure and cancer are extremely few in number. We set out to conduct a high-quality study to further investigate this potential relationship,” added Cassandra Clark, the study’s first author and a postdoctoral associate at the Yale Cancer Center. “Our results indicate that exposure to UOG may be an important risk factor for ALL, particularly for children exposed in utero.”
Oil and gas-related chemicals exposure could be through drinking water, the researchers found. The watershed, the zone from which a drinking water well serving their home would likely draw water, were compared with the distance from the home to the nearest of those UOG wells. UOG wells falling within the watershed area are expected to be more likely to impact the home’s drinking water supply, they said.
This work adds to a growing body of literature on UOG exposure and children’s health used to inform policy, such as setback distances (the required minimum distance between a private residence or other sensitive location and a UOG well). Current setback distances are the subject of much debate in the United States, with some calling for setback distances to be lengthened to more than 305m and as far as 1000m. The allowable setback in Pennsylvania, where the study was conducted, is 152m.
“Our findings of increased risk of ALL at distances of two kilometres or more from UOG operations, in conjunction with evidence from numerous other studies, suggest that existing setback distances, which may be as little as 150 feet (50m), are insufficiently protective of children’s health,” Clark said. “We hope that studies like ours are taken into account in the ongoing policy discussion around UOG setback distances.”
Source: Yale University
