Pennsylvania children living near unconventional oil and gas (UOG) developments at birth were two to three times as likely to be diagnosed with leukemia between the ages of 2 and 7 as those who did not live near this oil and gas activity, after accounting for other factors that could influence cancer risk, a novel study from the Yale School of Public Health has found.
The registry-based study, published in the journal Environmental Health Perspectives, included nearly 2,500 Pennsylvania children, 405 of whom were diagnosed with acute lymphoblastic leukemia (ALL), the most common type of cancer in children.
ALL is a type of leukemia that arises from mutations to lymphoid immune cells. Although long-term survival rates are high, children who survive this disease may be at higher risk of other health problems, developmental challenges, and psychological issues. Unconventional oil and gas development, commonly referred to as fracking (short for hydraulic fracturing), is a method for extracting gas and oil from shale rock. The process involves injecting water, sand, and chemicals into bedrock at high pressure, which allows gas and oil to flow into a well and then be collected for market.
For communities living nearby, UOG development can pose a number of potential threats. Chemical threats include, for example, air pollution from vehicle emissions and well and road construction, and 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 to cause cancer. The paucity of data on the association between UOG and childhood cancer outcomes has fueled public concerns about possible cancer clusters in heavily drilled regions and calls for more research and government action.
“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, MHS, PhD, 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, PhD ’22, 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.”