The reason it’s so tricky to quantify oil and gas emissions, let alone potential health impacts, is that they vary. A great deal, in fact.
Rob Jackson, an environmental scientist at Stanford University, said he’s seen many well pads with low emissions but some “leak a lot.” Even near a single site, two families could have very different experiences if one is typically upwind and the other downwind, he said.
“I’m not trying to generate a crisis,” Jackson said. “But I think air quality for people living near any industrial operation is a potential issue, and … air quality and human health issues are likely to be very important for a minority of people living near oil and gas operations. We just don’t have a good idea of who they are.”
When Texans suspect they fall in that group, they can contact the TCEQ and have an investigator come out to do brief testing. Bob Parr, whose family called the agency frequently in 2010 and 2011, has a term for that: “trying to chase air” — hours or days after the problem started, at which point the wind, the emissions or both might have changed.
It took two days on average for investigators to respond to air complaints related to oil and gas the last two fiscal years in the Barnett, Clawson said, though the agency prioritizes health complaints when those come in.
In some of the cases in which investigators found violations, they did so by arriving on the weekend or in the middle of the night — times when problems often seem to crop up, residents say.
Parr’s wife, Lisa, said she prevailed on the TCEQ to send an employee one particularly bad Sunday evening in 2010. The Parrs raise cattle in Wise County, a more rural part of the Barnett, and they’re ringed by wells. Investigators showed up in time to get a whiff of the fumes sickening the Parrs — 30 seconds in the plume of toxic compounds was enough for one of the men to feel dizzy and develop a sore throat.
The report described “very strong, offensive odors.” The air test came back with chemicals over the TCEQ’s guidelines. Contractors were just finishing up work called a nitrogen lift on one of the wells, and Lisa Parr doubts an investigation the next day would have done much good.
After another bad evening a few months earlier, she said, the TCEQ found nothing of concern in the air. That time, the investigator arrived the following morning.
David R. Brown, a public health toxicologist working for the nonprofit Southwest Pennsylvania Environmental Health Project, said his group’s measurements show emissions from wells and compressor stations typically have big fluctuations. Any monitoring that isn’t continuous can miss the irregular spikes reaching nearby residents, he said.
“The exposures are very high exposures for short periods of time,” said Brown, an official at the federal Agency for Toxic Substances and Disease Registry in the 1990s. “And so a person can get a tremendous dose in an afternoon.”
One problem after another
Annette Wilkes was sitting in her backyard in Flower Mound in 2004 when she got her first clue that a natural gas well had been drilled in the North Texas community, less than half a mile from her property.
“We saw them flaring,” said Wilkes, now 43. “We wondered what it was.”
She had to stop taking her children to the elementary school playground beside the field with the gas-well pad because her eyes would swell up in what seemed like severe hay fever. But she didn’t spend much time thinking about the new neighbor. She had other matters on her mind.
Her sinus issues rapidly worsened, eventually prompting two surgeries to try to get the infections under control. Around the same time, she lost much of her hair. Alopecia areata, her specialist said — an autoimmune disease.
“He put me in the allergy category,” she said, meaning she was reacting to something — what, no one knew. “He could not believe I’d never had alopecia before because it was such an extreme case.”
In 2006 her then 3-year-old son was diagnosed with a type of periodic fever syndrome that doesn’t have a known cause. His temperature would spike as high as 104 degrees for several days straight every few weeks, requiring frequent doses of medicine to keep the fever from turning dangerous.
Then Wilkes was diagnosed with Hashimoto’s disease, a thyroid-attacking autoimmune disorder. It was so advanced that she needed surgery to remove her thyroid.
Early on in this parade of bad news, Wilkes — who had previously been healthy — went searching for external explanations. Mold in the house, maybe? Her husband was having “bizarre skin reactions,” after all. But a mold test found nothing.
Others in her immediate neighborhood fell ill, too.
A next-door neighbor died of leukemia. Within a block, one woman developed a brain tumor and another was suffering from what turned out to be multiple myeloma.
Lorrie Squibb, diagnosed in 2010 with that blood cancer, said the first words out of her doctor’s mouth were, “What have you been exposed to?”
“I was 40 years old,” said Squibb, a stay-at-home mother who had just moved from Flower Mound to Michigan. “I was the second-youngest my oncologist has ever seen with multiple myeloma.”
Like Wilkes, Squibb is convinced gas development made her sick. As children in the neighborhood developed cancer, others had the same thought.
In 2010 and 2011, the Texas Department of State Health Services responded to the concerns by tallying several types of cancer in the two ZIP codes that cover most of Flower Mound to see whether the cases were higher than expected.
The state calculated its figures using a 99-percent confidence interval. That meant the number of cancer cases had to be so elevated that there was only one chance in 100 that happenstance alone was responsible.
Using this standard, staffers concluded that only breast cancer was higher than expected, and they thought population growth could explain that.
This spring an article in an environmental law journal said that if the state had used a 95-percent calculation, more typical in such cases, it would have found clusters of blood cancers among boys — lymphoid leukemia in one ZIP code and non-Hodgkin lymphoma in the other.
The attorney who wrote the article, University of Texas at Austin researcher Rachael Rawlins, also suggested that studying a smaller area than broad ZIP codes might have better addressed people’s fears about specific neighborhood exposures.
The state health agency responded with another analysis — this time using a 95-percent calculation with more recent cancer data, but still focused on the two ZIP codes that bisected the town. Christine Mann, a spokeswoman for the state health department, said it wasn’t possible to analyze the cases in neighborhoods because the numbers would be too small to produce statistically valid results.
Again, only breast cancer was higher than expected. Again, the agency suggested that problems other than environmental exposure could explain it.
“Relative to other risk factors, the chance of a person developing cancer as a result of exposure to an environmental contaminant is small,” the July report said. It cited an estimate, drawn from 1981 research, that exposure to environmental contaminants is to blame for only 2 percent of cancer deaths.
But that figure is far from universally accepted. A presidential advisory panel declared in 2010 that “the true burden of environmentally induced cancer has been grossly underestimated.”
When asked about that, Mann said the point of the Flower Mound study wasn’t to evaluate “environmental or other risk factors,” simply to look at the number of cancer cases there.
Flower Mound now has among the most restrictive gas-development rules in the Barnett, including a setback preventing drilling within 1,500 feet of homes. Wilkes, who moved her family out of Flower Mound in 2006 after deciding gas-extraction was the root of her problems, returned three years later to a neighborhood where she felt comfortable no drilling would occur.
Her health has improved. Her son’s fevers stopped.
Like other residents, she sees no way to definitively prove why it all happened in the first place.
“That’s what drives me crazy,” Wilkes said.