A UCLA-USC study published Wednesday suggests that flaring — the burning off of excess natural gas — can increase the risk of preterm births in women living nearby.
Preterm babies are at greater risk of lung and breathing problems at birth, as well as long-term developmental disabilities.
Researchers at the UCLA Fielding School of Public Health and USC Keck School of Medicine studied the Eagle Ford Shale of south Texas to examine whether living in close proximity to flaring from oil and gas development was associated with shorter gestation periods and reduced fetal growth.
“Prior studies suggest living near oil and gas wells adversely affects birth outcomes, but no studies had yet examined flaring — the open combustion of natural gas,” said Lara Cushing, an environmental health scientist with the Fielding School. “Our findings suggest that living within three miles of flaring adversely impacts pregnant women and infants in Texas’ Eagle Ford region.”
The study, published Wednesday in the journal Environmental Health Perspectives, concludes that exposure to a high number of nightly flare events was associated with 50% higher odds of preterm birth and shorter gestation than zero exposure.
Fifty-five percent of the women in the study identified as Latina or Hispanic, and the risk for preterm birth among Hispanic women exposed to high levels of flaring was greater than it was for non-Hispanic white women, who made up 37% of the study.
Researchers said they controlled for other variables such as age, smoking, insurance status and access to prenatal care.
Researchers tracked 23,487 live single births between 2012 and 2015 near the Eagle Ford Shale. The area measures 50 miles wide and 400 miles long and is one of the most productive oil and gas regions in the country, due to drilling practices such as hydraulic fracturing, known as “fracking.”
Natural gas is an unwanted byproduct of oil extraction and is burned off if it cannot be readily sold at a profit or poses a safety problem. In a previous study, the research team estimated the area was subject to more than 43,000 flaring events between 2012 and 2016.
Flares, which can burn for weeks at a time, have been shown to release a variety of chemicals, such as benzene, as well as fine particle pollution, carbon monoxide, nitrogen oxides, heavy metals and black carbon. Several of these combustion-related pollutants have been associated with a higher risk of preterm and reduced birth weight in other contexts.
“The fact that much of the region is low-income, and that approximately 50% of residents living within three miles of an oil or gas well are people of color, raises environmental justice concerns about the oil and gas boom in south Texas,” said Jill Johnston, an environmental health scientist at the USC Keck School of Medicine, who co-led the study with Cushing.
The researchers called for policies and strategies to limit flaring.
“Measures to minimize flaring — such as more stringent regulation of flaring, or investments in renewable energy and energy efficiency measures that reduce reliance on fossil fuels overall — would protect the health of infants,” Johnston said.
Simply living near a concentration of oil and gas wells may also raise risks. Women who lived within three miles of a high number of oil and gas wells were found to have higher odds of a preterm birth than mothers who did not live near wells. Their babies were also born weighing roughly 7 ounces lighter, on average.
According to the study’s authors, the United States is responsible for the highest number of flares of any country, flaring an estimated 14.1 billion cubic meters of natural gas in 2018. Roughly 80% of flaring — which remains largely unregulated and underreported — is happening in Texas and North Dakota, they said.