Baby and father

Babies born near natural gas flaring are 50 percent more likely to be premature: Study

Researchers link air pollution from burning off excess natural gas to preterm births for babies; with the most pronounced impacts among Hispanic families.

Living near fracking operations that frequently engage in flaring—the process of burning off excess natural gas—makes expectant parents 50 percent more likely to have a preterm birth, according to a new study.


A birth is considered preterm when a baby arrives before 37 weeks (about eight and a half months) of pregnancy. Preterm births can result in underdeveloped lungs, difficulty regulating body temperature, poor feeding, and slow weight gain in babies.

Fracking, another name for hydraulic fracturing, is a process of extracting oil and gas from the Earth by drilling deep wells and injecting liquid at high pressure. While many studies have established links between living near fracking wells and numerous health effects, including preterm births, this is the first study to specifically investigate the health impacts of flaring.

Flaring is most commonly used when the primary goal of fracking is oil extraction, so it's cheaper to burn off the natural gas as a waste byproduct than it would be to capture, transport, and sell it. Flares can burn for weeks at a time, releasing combustion-generated pollutants like benzene, fine particulate matter pollution, carbon monoxide, nitrogen oxides, heavy metals and black carbon.

The study, published today in the journal Environmental Health Perspectives, looked at satellite data showing the location and duration of flares, and at hospital records from 23,487 births for parents living in the rural region of Eagle Ford, Texas between 2012 and 2015. In a previous study, the same researchers estimated that the Eagle Ford shale region, which is home to more than 7,000 fracking wells, had more than 43,000 flaring events between 2012 and 2016.

"We found that among mothers living within five kilometers (or about three miles) of a high amount of flaring activity during pregnancy, we saw 50 percent higher odds of preterm birth compared to mothers that had no exposure to flaring," Jill Johnston, one of the study's lead authors and an environmental health scientist at the Keck School of Medicine of the University of Southern California, told EHN.

A high amount of flaring was defined in the study as 10 or more nightly flare events within three miles of the pregnant parent's home. The researchers adjusted for the pregnancy risk of just living near oil and gas operations in general, and for other known risk factors for preterm birth including age, smoking, insurance status and access to prenatal care, to ensure that the increased risk they were seeing was just associated with flaring.

While looking at the density of wells, the researchers found that expectant parents who lived within three miles of a high number of oil and gas wells also had higher odds of a preterm birth than parents who did not live near wells, regardless of flaring. They also observed that babies born to parents who live near a high number of wells were smaller, weighing an average of about seven ounces less than babies born to parents who didn't live near fracking wells.

Fracking flaring North Dakota

Flaring in the Bakken shale in North Dakota. (Credit: Trudy E. Bell)

Environmental injustice

Johnston and colleagues found that parents in the study who identified as Latina or Hispanic were exposed to more flaring, and were more likely than White parents to see an increased risk of preterm birth.

"I think that racial disparity is an important finding, and we need more research on the reasons behind it," Johnston said, noting that prior research has shown more vulnerability of women of color to effects of air pollution when looking at adverse birth outcomes.

"It's possible that a lifetime of discrimination and social stressors are driving factors here. It could also be that Hispanic families are spending more time outside and being more exposed to pollution from flares," Johnston added.

Hispanic communities in the region are exposed to more frequent flaring than White communities, Johnston said, which could also mean that even among the "high-flare group" in their study, Hispanic parents were being exposed to a higher number of flares every night than White counterparts.

"Historically, much of the waste disposal in the U.S. is concentrated in communities of color," Johnston added. "One theory is that we're seeing the same pattern with flaring, which is essentially another type of waste disposal. Infrastructure investments can be made to capture excess natural gas rather than burning it off, and where those funds are invested to minimize flaring often seems to depend on the characteristics of the communities nearby."

Flaring on an Ohio well pad in 2016. (Credit: Ted Auch, FracTracker Alliance)

A lack of health-protective regulations

It's estimated that globally, more than 139 billion cubic meters, or about 4.6 percent of all natural gas production, is flared every year.

Following the fracking boom that started in the U.S. around 2006, the U.S. became responsible for the highest number of flares of any single country, burning an estimated 13.2 billion cubic feet of natural gas in 2018.

In a previous study, Johnston and her research team estimated that about 80 percent of U.S. flaring is occurring in the Texas and in North Dakota shale plays, where much of the country's oil-extractive fracking occurs. In places like Pennsylvania, where fracking companies primarily extract natural gas, some flaring occurs, but it's less common since most of the gas is captured and sold.

Despite the high level of flaring that's occurring in the U.S. and in Texas, there are few federal or state regulations on the practice, and most of the data on flares is sporadically self-reported by the industry.

"It would have been really difficult to do this assessment if we didn't have satellite data and had to try to sort through the spotty state-level data that was available," Johnston said. She pointed to the Energy Policy Act of 2005, which prompted deregulation of the oil and gas industry nationwide, as a likely cause for the lack of regulations and data on flaring. In the last four years, the Trump Administration has been working to further reduce the number of regulations on the industry.

If expectant parents notice flaring activity nearby, Johnston recommended reducing exposure to airborne pollutants as much as possible by staying indoors, keeping the windows closed to reduce the amount of outdoor air that gets into the house, and using an air filter to purify indoor air.

"Our study indicates that there are serious public health concerns associated with living near flaring," Johnston said. "I believe that regulatory efforts to reduce and eliminate the amount of flaring that's occurring would be beneficial to communities nearby."

Banner photo credit: skalekar1992/Pixabay

Manufacturing plant with smoke rising from towers

How has climate change reshaped drought in the West Midlands?

The origins of the "flash drought" and how things compare to the conditions of 1976.
An aerial view of the Pentagon

U.S. Federal judge orders Pentagon to lift freeze on wind power

Since April, the Defense Department has halted all military reviews for wind projects, stalling dozens of projects nationwide.
NEW YORK CITY - SEPTEMBER 3 2015: Republican candidate for president Donald Trump announced he had signed a pledge not to run as an independent candidate should he fail to win the party's nomination in 2016.
Credit: andykatz/BigStock Photo ID: 100778843

Trump administration to pay German firm $1.22B to cut offshore wind leases

Agreement with RWE is the fifth deal Trump team has made with energy companies, offering payouts to give up projects.

A man wearing a hardhat on a roof inspecting solar panels

Utah produced more power from solar than any other source in May, marking a new first

Wind and solar generation are surging in Utah’s power mix, and experts expect the trend to continue despite cuts to federal clean energy incentives.

Computer generated 3D illustration with oil pumps, solar panels and wind turbines
Credit: MIRO3D/BigStock Photo ID: 147195269

How solar donors helped take down a Trump-backed Republican

A pro-renewable energy political action committee was behind Representative Andy Ogles' primary loss Thursday.

Sunlight shines over river bed
Photo by Trac Vu/Unsplash

Texas governor blasted Corpus Christi for its water crisis. A river authority he has power over is falling apart

The Nueces River Authority is working on a project that could expand the Corpus Christi region’s water supply, but the Texas governor has done little to address the agency’s financial problems, despite appointing every member of its board.

From our Newsroom
Multiple Houston-area oil and gas facilities that have violated pollution laws are seeking permit renewals

Multiple Houston-area oil and gas facilities that have violated pollution laws are seeking permit renewals

One facility has emitted cancer-causing chemicals into waterways at levels up to 520% higher than legal limits.

Regulators are underestimating health impacts from air pollution: Study

Regulators are underestimating health impacts from air pollution: Study

"The reality is, we are not exposed to one chemical at a time.”

Pennsylvania governor Josh Shapiro speaks with the state flag and American flag behind him.

Two years into his term, has Gov. Shapiro kept his promises to regulate Pennsylvania’s fracking industry?

A new report assesses the administration’s progress and makes new recommendations

silhouette of people holding hands by a lake at sunset

An open letter from EPA staff to the American public

“We cannot stand by and allow this to happen. We need to hold this administration accountable.”

wildfire retardants being sprayed by plane

New evidence links heavy metal pollution with wildfire retardants

“The chemical black box” that blankets wildfire-impacted areas is increasingly under scrutiny.

Stay informed: sign up for The Daily Climate newsletter
Top news on climate impacts, solutions, politics, drivers. Delivered to your inbox week days.