Unsafe Exposure

A new study has found unsafe levels of polycyclic aromatic hydrocarbons (PAHs), linked to cancer and respiratory illness, near fracking sites in Carroll County, Ohio. The study, published in Environmental Science and Technology, was conducted by a research team headed by Drs. Kim Anderson of Oregon State University and Erin Haynes of the University of Cincinnati. The first author was Blair Paulik, an OSU graduate student. The article is gated, but secondary sources, including an OSU press release, give what appears to be a complete, though non-technical, description of the study.

Carroll County, 70 miles southeast of Cleveland, has 30,000 residents, lies on the Utica Shale formation, and had 421 natural gas wells at the time of the study, February 2014. (It now has 480.) The study was initiated by concerned citizens who contacted Dr. Haynes.  

Air samplers were placed on the properties of 23 volunteers who lived within 3 miles of gas wells. The monitors contained treated materials that absorbed contaminants. They were sealed in airtight bags and shipped to Dr. Anderson's lab for analysis. Volunteers were trained in proper collection and handling of the data.

PAHs are hydrocarbons (compounds of carbon and hydrogen), seven of which, i.e., benzopyrene, are classified by the Environmental Protection Agency as carcinogenic. Prenatal exposure is also associated with lower IQ and childhood asthma. Based on their data, the authors calculated that the lifetime cancer risk for those living closest (.1 miles) to the wells is 2.9 in 10,000. This is almost three times the EPA's acceptable level of 1 in 10,000. Levels of PAHs declined 30% at a distance of three miles—still well above the acceptable limits. Levels were about 10 times higher than a rural Michigan county containing no gas wells.

Researcher Blair Paulik in front of an air sampler
(© Oregon State University)

In googling the study, I found an article in Marcellus Drilling News, a pro-fracking website, calling this a “sham study.” Some of their objections were silly, i.e., that the OSU authors were “a long way from home,” and that the article “sneaks in the c-word.”  (Estimating cancer risk was the point of the study.) I found three possibly substantive criticisms: that there were too few data collection sites, that they were not randomly distributed throughout the county, and that the data were collected by “untrained volunteers.” The third objection is false, but if the samples were carelessly handled, it's likely they would have captured fewer, not more, contaminants. Since neither the gas wells nor the human population are randomly distributed within the county, I doubt the value of including data from locations that are far from either gas wells, people or both (although it certainly would have diluted the findings).

Future studies should randomly select fracking sites and collect more samples at varying distances from the wells, including some more than 3 miles away, to establish the physical boundaries of the contamination.

You might also be interested in reading:

Is Fracking Safe?

Fracking and Public Health, Part 1

Fracking Up Baby

Fracking and Public Health, Part 2

The Coverage

Please read part 1 about the Rabinowitz survey of fracking and health.

With the exception of USA Today, the response of the corporate media to the Rabinowitz study has been a collective yawn.

Since Washington County is part of the area served by the Pittsburgh Post-Gazette, one might expect the survey to be front-page news. On the contrary, the study was buried in a short article on page 4 of the local section, with what seems like a deliberately uninformative headline, “Study looks at gas wells, health.” Three of its nine paragraphs were devoted to rebuttal from Travis Windle, a spokesman for the Marcellus Shale Coalition, an industry group.

© All rights reserved by jeffs4653

In an unusually harsh attack on the integrity of the researchers, Mr. Windle stated, "This study, done in partnership with a local activist group, was designed to put selective and unproven data behind a predetermined and biased narrative." The activist group is presumably the Southwest Pennsylvania Environmental Health Project, which is opposed to fracking. They are credited with assistance with the survey; specifically: "The survey was pre-tested with focus groups in the study area in collaboration with a community-based group and revised to ensure comprehensibility of questions." If this is all they did, they played only a limited role in the study.

Pittsburgh's avowedly right wing newspaper, the Tribune-Review, offered an unusual take on the Rabinowitz study. First of all, they claim that this study is balanced by a “confllicting” 2014 study by Penn State geologist Terry Engelder and colleagues. This study found no evidence that fracking fluids, injected deep underground into the Marcellus shale, were migrating toward the surface and contaminating the ground water. Rather than conflicting, the two studies are actually irrelevant. Rabinowitz attributed the symptoms he discovered to air pollution, pollution of ground water from fluids leaking from around the drilling site, and stress. Migration of deep underground fluids, if it occurs, is presumably a problem for future generations to deal with, long after the drilling companies have taken their money and run.

The Tribune-Review also suggested that both studies are biased due to their source of funding. The Engelder study was supported by the Marcellus Shale Coalition and included an employee of Shell International as one of its co-authors. The primary supporter of the Rabinowitz study was the non-profit Heinz Foundation. The Heinz Foundation underwent a turnover of its executive staff beginning in August 2013, which is widely interpreted as a shift toward opposition to fracking. Previously, Heinz had been a member of the Center for Sustainable Shale Development, a coalition of environmental and industry groups that was supposed to establish voluntary safety rules for drilling. However, the Rabinowitz study was completed in 2012, while Heinz was still friendly with the drilling industry.

It's clear that we need an improved vocabulary for talking about real or imagined conflicts of interest in research, one which, at a minimum, distinguishes between financial and ideological conflicts of interest. If your research is supported by a for-profit corporation and its results are contrary to corporate interests, two consequences are likely. First, the research results will never be made public, and second, you will never again receive financial support from that corporation. Those outcomes are unlikely when your research is supported by a non-profit foundation.

The Tribune-Review seeks to expand the category of conflicts of interest to include those cases when the researchers or their sponsors have an opinion about the research topic. But this is unrealistic, since investigators almost always have opinions about their research, opinions which often explain why they were interested in the topic in the first place. Even when the research topic is completely non-political, scientists are often professionally committed to their research hypotheses. Good research design ensures that the researchers' expectations, and those of their financial supporters, do not influence the results.

I can't comment on the design of the Engelder study because I lack expertise in geoscience. I described the Rabinowitz study in some detail because it seems to me that the authors have done a good job, under the circumstances, of minimizing researcher bias and evaluating alternative explanations. Right now, the best advice to people on both sides of the issue is replicate, replicate, replicate. For example, studies of fracking and health are in progress at the Geisinger Health Center in central Pennsylvania. Ultimately, whether researchers have successfully eliminated bias is an empirical question. If studies are replicated often enough, it should be possible to determine through systematic reviews whether researchers with different sources of funding have obtained inconsistent results.

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Fracking and Public Health, Part 1

Fracking Up Baby

Motivated Reasoning

Fracking and Public Health, Part 1

An Important First Study is Published

Corporations that engage in mining and manufacturing are extremely fortunate that Americans cannot be randomly assigned to places of residence. This prevents researchers from doing true experiments--that is, randomly assigning people to experimental and control groups to study the effects of air, water and soil pollution on public health. As a result, when epidemiologists, who study the spatial distribution of health and illness, find evidence of illness concentrated in the vicinity of sources of industrial pollution, it its always possible for corporations to claim that something else—known or unknown—is responsible. Correlation does not mean causation.

On Wednesday, what is to my knowledge the largest scientific study relating proximity to natural gas wells to human health, conducted by a team led by Peter Rabinowitz of the Yale School of Medicine, was released online by the peer-reviewed journal Environmental Health Perspectives. Previous evidence of an association between natural gas drilling and illness had come either from case studies or convenience—that is, nonrandom—samples.

Photo by Ruhrfisch

The study was done in Washington County, south of Pittsburgh, which had 624 active natural gas wells, 95% of which utilized hydraulic fracturing. A set of 38 contiguous rural communities were selected for study, to avoid urban areas unlikely to have ground-fed wells. Within these communities, 760 geographic points were randomly chosen and the nearest residence was selected for study. Some sites were excluded due to duplication, because there were no homes nearby, or because the house did not have a ground-fed well. This left 255 eligible households, 180 (71%) of which agreed to participate. Forty-seven households refused to participate, and researchers were unable to contact residents of the remaining homes.

Participants were interviewed in their homes in the summer of 2012 by trained survey researchers who followed a prepared script. The survey made no reference to natural gas drilling. Researchers were unaware of the home's proximity to the nearest gas well. (Of course, this precaution failed if a drilling rig was visible from the front porch.) An adult member of the household was asked questions assessing the health status and symptoms of each member of the household—a total of 492 people. Participants were paid $25. Participating households were divided into those within 1 kilometer (.6 miles) of a natural gas drilling site, those between 1 and 2 km, and those more than 2 km from the nearest site.

Respondents were asked about six types of health problems: dermal, upper respiratory, lower respiratory, gastrointestinal, neurological and cardiovascular. The following variables were statistically controlled: age, gender, education, occupation, the presence of smokers or pets in the home, and awareness of nearby environmental hazards. Statistically significant results were obtained in two of the six health areas, dermal and upper respiratory.

• Upper respiratory symptoms, such as coughing, itchy eyes and nosebleeds, were reported by 39% of those living within a km of a drilling site but only 18% of those who lived more than 2 km away. Both the near and intermediate groups reported significantly more upper respiratory symptoms than the far group.
• The number of people suffering from dermal problems was smaller, but the association was stronger. Thirteen percent of those living nearest to a gas well suffered from skin problems, such as rashes, itching and burning, but only 3% of those living the farthest away. The near group reported significantly more dermal symptoms than the far group.

The authors do not claim that their data show a causal relationship between drilling and health problems. However, they speculate that, if natural gas drilling is responsible for these skin and respiratory issues, it could have happened through three pathways: (1) pollution of ground water, including the water in their wells; (2) air pollution from the drilling site; and (3) stress due proximity to a drilling site. Noise is a particularly potent stressor. Supporting the stress hypothesis is the fact that those who were aware of nearby environmental hazards reported more skin and respiratory symptoms, although the relationship between proximity and symptoms was still significant when the effect of awareness was statistically removed.

Whenever a relationship between industrial pollution and illness is found, the most likely alternative explanation is the indirect involvement of social class. Locations that are close to sources of pollution are usually undesirable places to live. Property values are lower and people living nearby have lower incomes. We know that, for a variety of reasons, lower income Americans are in poorer health. However, this explanation is weakened somewhat by the fact that almost all the natural gas wells in Washington County were drilled within the last 5-6 years. This allowed less time for migration to occur and for pockets of poverty to form around the drilling sites.

Because the researchers relied on self-report data, it's possible that people living close to drilling sites exaggerated their symptoms—although they might also have had reasons to minimize them. The fact that the results were still strong when awareness of environmental hazards was controlled argues against this interpretation. Future researchers should consider conducting actual medical examinations of the participants. This would of course be much more expensive and logistically challenging.

The 71% completion rate is well above average for surveys. However, it might be argued that people experiencing illnesses that they attributed to local drilling were more anxious to tell their story, and that this contributed to an overestimation of the percentage with health problems. However, the refusal rate did not vary significantly with distance from the nearest drilling site.

The health problems detected in the study were among the least serious included in the survey. Since most of those surveyed had only been living near a gas well for a short time, the authors say they were not surprised that diseases with longer latencies, such as heart conditions or cancers, were not yet associated with proximity to a drilling site.

The research was supported by a grant from Pittsburgh's Heinz Foundation, along with four other non-profit sources. The authors thanked the Southwest Pennsylvania Environmental Health Project for “assistance with the community survey.” They conclude by calling for further research, including “longitudinal assessment of the health of individuals living in proximity to natural gas drilling activities, medical confirmation of health conditions, and more precise assessment of contiminant exposures.”

To be continued in Part 2.

You may also be interested in reading:

Fracking and Public Health, Part 2

Fracking Up Baby

La Terra Trema

Romneycare: The Bottom Line

Sometimes we get so caught up in the details of health care reform that we forget the real purpose—to improve people's health. A new study by Charles Courtemanche and Daniela Zapata, published by the National Bureau of Economic Research, examines the health effects of Massachusetts' 2006 health care reform bill, commonly called “Romneycare.” This effects of this reform are important because it is nearly the same as the Affordable Care Act (ACA).

It may sound silly to ask whether expanding people's access to medical care improves their health, but the outcome of the study was not obvious. Critics of health care reform sometimes claim that people will not take advantage or make good use of medical care and their health will be unchanged. More importantly, the moral hazard hypothesis claims that when health care is available at low cost, people will take unnecessary health risks, such as smoking and overeating. The result could be a decline in their overall health, accompanied by an increase in medical spending.

Previous studies have generally found improvements in health following increased access to care. The most impressive is the Oregon Health Study, which found a 13% increase in the number of people reporting themselves to be in good or excellent health following enrollment in Medicaid.

The data for this study come from a survey conducted by state health departments and the Center for Disease Control between 2001 and 2010. It includes answers from 2.8 million respondents from all 50 states and the District of Columbia. The study is a time series design. Health care reform in Massachusetts went into effect in March 2006, but the implementation was gradual and was not completed until July 2007. The research question is whether there were any changes in the health of Massachusetts residents around those times that did not occur in other states. The analysis controls for irrelevant variables such as age, income and marital status.

The main dependent measure was a self-report health question asking respondents to classify their overall health as either poor, fair, good, very good, or excellent. The results showed an improvement in health while the reform was being implemented (from April 2006 to July 2007), and approximately twice as large an improvement after it was fully implemented. These changes did not occur in other states at the same time. To put this into perspective, it is estimated that 1.4% of the population went from being in either poor, fair or good health to either very good or excellent health. Considering the overall cost of the program, Massachusetts spent $9,782 per year for every individual whose health improved from poor, fair or good to very good or excellent. Of course, having more people in very good or excellent health might save money in the long run.

This analysis includes everyone. However, if you look specifically at those people who acquired health insurance as a result of the reform, their probabilities of being in poor, fair or good health went down by 6.2%, 9.8% and 8.5% respectively, while their probability of being in very good health and excellent health went up 8.5% and 16%. This is comparable to the results of the Oregon study.

The main concern about this measure is that self-report questions are subjective and can be influenced by various biases. For example, people might have expected their health to improve due to the reform. On the other hand, access to medical care might make people more aware of the health problems they have. Therefore, the survey included several other measures. People were asked the number of days out of the past 30 that they were not in good physical health, that they were not in good mental health, and that they experienced health-related functional limitations. They were also asked the number of minutes per week they spent in moderate and vigorous physical activity, whether they experienced joint pain, and whether they smoked. Finally, their body mass index (weight/height²), or BMI, was calculated. Since these questions are more specific, they should be less subject to bias.

The results showed significant improvements on all of these measures with the exception of vigorous exercise and smoking. The fact that smoking did not increase and that BMI was reduced casts doubt on the moral hazard hypothesis that people would take more health risks. In fact, the overall pattern suggests that people were heeding medical advice.

Finally, internal analyses showed that, while almost every subgroup showed improvements in health, women improved more than men, and people between 55 and 64 (the oldest group not eligible for Medicare) showed the greatest improvement. Those in the lowest income category, who were eligible for a state subsidy to help purchase their insurance, showed greater improvement, and blacks improved more than other races. The authors estimate that health care reform reduced black-white health inequality by 21.5%.  

Does this study predict a positive effect of the ACA on health if it is implemented? Maybe. But the ACA includes cost-cutting measures that were not part of the Massachusetts plan, such as reductions in Medicare spending, which might reduce the gains that would otherwise be expected. On the other hand, Massachusetts had one of the lowest percentages of uninsured citizens of any state, so implementing these same reforms nationwide might result in a greater improvement in the health of the nation.

I presume these successful results will be embarrassing to Governor Romney, who has repudiated his own health care reform in search of the approval of the bewildered herd of Elephants.  

Correction.  If you read "What the Data Say" yesterday, please note that I have corrected a mathematical error.  The effect of the error was to make the increase in 2012 campaign spending appear greater than it actually was.  I should have followed my own advice and thought more slowly.

Fracked Again

HB1950, Pennsylvania's natural gas impact fee bill, is 173 pages long and we are gradually learning what it says. An ethical as well as a public health issue associated with the bill has been raised by Dr. Bernard Goldstein of the Pitt School of Public Health and his colleague Jill Kriesky. You've probably heard of the Halliburton loophole—the federal law that allows drilling companies to keep the formula for fracking fluid secret, even though it is known to contain toxic elements. HB1950 preserves that secrecy, and requires physicians to violate medical ethics in order to maintain it.

A physician treating a patient suffering from toxic exposure can request the proprietary formula for fracking fluid, but must sign a legally binding nondisclosure agreement. He or she can use it only to treat the specific patient for whom the information is requested. A physician may not use the information to treat another patient suffering the same symptoms, or to warn neighbors of the danger. Above all, doctors may not reveal the industry's secret formula in order to alert the general public to a public health hazard—which is almost certainly what the industry is most concerned about.

Imagine that one of your family members dies because a physician was forbidden to warn them about a known carcinogen in your drinking water. I guess that's the public health policy we can expect when our state government is a wholly-owned subsidiary of the natural gas industry.