Study of Natural Gas Flaring Finds High Risks to Babies

Newswise — LOS ANGELES – Researchers from the UCLA UCLA Fielding School of Public Health and USC Keck School of Medicine have found that exposure to flaring – the burning off of excess natural gas – at oil and gas production sites is associated with 50% higher odds of preterm birth, compared with no exposure.

“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 J. 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 appears July 15 in the journal Environmental Health Perspectives. Researchers examined 23,487 live single births to women living within Texas’ Eagle Ford Shale between 2012 and 2015. The Eagle Ford Shale, measuring 50 miles wide and 400 miles long, is one of the most productive oil and gas regions in the country, due to unconventional drilling practices such as hydraulic fracturing (“fracking”). In a previous study, the research team estimated the area was subject to more than 43,000 flaring events between 2012 and 2016.

Of the live births researchers analyzed, 10.6% were preterm, occurring before the 37th completed week of pregnancy. Preterm birth is associated with complications such as immature lungs, difficulty regulating body temperature, poor feeding, and slow weight gain. Of the births in the high flare exposure group analyzed by researchers, 14% were preterm.

“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. “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.”

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 birthweight in other contexts.

The researchers used satellite observations to measure flaring activity because systemic reporting of flaring is lacking. The team adjusted for other known risk factors for preterm birth in their analysis, including age, smoking, insurance status, and access to prenatal care, and concluded that exposure to a high amount of flaring was associated with 50% higher odds of preterm birth, compared with no exposure. A high amount of flaring was defined as 10 or more nightly flare events within 5 km (3 miles) of the pregnant woman’s home.

Women who lived within 5 km (3 miles) of a high number of oil and gas wells also had a higher odds of a preterm birth than mothers who did not live near wells. Their babies were also born weighing 19.4 grams (7 ounces) lighter on average. This suggests that in addition to flaring, other exposures related to oil and gas wells may also be adversely impacting pregnancy, the researchers said.

The majority (55%) of the women in the study population identified as Latina or Hispanic, and the odds of preterm birth among Hispanic women exposed to high levels of flaring was greater than the corresponding odds among non-Hispanic white women, who made up 37% of the study population. Nearly 60% of women in the study were on public health insurance (Medicaid) and 17% were foreign born.

In recent years, the US was responsible for the highest number of flares of any country globally, flaring an estimated 14.1 billion m³ of natural gas in 2018. Some 80% of flaring is occurring in the Texas and North Dakota shale plays, where much of the U.S. unconventional oil production occurs. Yet, flaring largely remains underreported and unregulated, the researchers said.

In addition to Johnston and Cushing, other authors of the study include Kate Vavra-Musser, Khang Chau and Meredith Franklin, all of USC. The study was supported by a grant from the U.S. National Institutes of Health/National Institute of Environmental Health Sciences.