Myths About Fracking Explained, #5: “Shale Gas Poses Minimal Risk to Public Health”

by Sandra Steingraber, PhD
Distinguished Scholar in Residence
Department of Environmental Studies
Ithaca College, Ithaca, New York
[email protected] 

prepared remarks for presentation (via Skype) at the public conference, Unfracked: Why Shale Gas Should Stay in the Ground, European Parliament, Brussels, 5 September 2013

recorded livestream:

Bonjour.  Guten Tag. Good morning from the Fingers Lakes region of New York State.

One thousand meters or so below the room where I am speaking lies a layer of shale bedrock that contains an enormous amount of methane. This gas is not contained within large underground balloons.  Instead, it is scattered throughout the shale as tiny bubbles—like spilled champagne locked inside of stone.

To extract these gas bubbles profitably would require smashing apart our bedrock using high-pressure blasts of water as a hammer.

The shale underneath my house is, so far, unsmashed, and we New Yorkers intend to keep it that way.  Our resolve and our political struggle, which you have heard about today from my U.S. colleague John Armstrong, are animated by many concerns.

One of them is the threat that shale gas extraction—and its associated infrastructure—poses to public health.

And, as an aside, let me first say how inspired we feel in the U.S. by the European anti-fracking movement.  I believe you saw, in John’s presentation, a photograph of bread loaves piled before the governor’s office in New York with a sign saying, “Farmers Against Hydrofracking.”  Those bread loaves were part of an action that was directly inspired by a YouTube video of a protest Bulgaria in which loaves of bread were marched through the streets. Likewise during a recent demonstration here in New York when President Obama visited, there was much conversation about the powerful protests going on at the same time across the Atlantic in Balcomb, England.

The emerging science suggests that the risks to public health from fracking are widespread and costly.  They are also not fixable by regulation or existing technology.  If underground sources of drinking water are contaminated, these risks extend to future generations. Fracking is inherently dangerous to public health.

My task today is to describe for you some of these threats and the evidence for them.

However, I’d first like to explain why I am here in New York rather than with you in Brussels.  And if I’m clever, my explanation will serve as a starting point for my remarks.

This summer, my otherwise healthy, thin husband—with good blood pressure and a kind heart—suffered from two strokes.  (Stroke in French, I believe, is “attaque cerebrale” and in German, ein Schlaganfall.)  Jeff is, happily, now recovering, but I need to remain by his side.  So, I thank my hosts, the EU Greens and the European Free Alliance, for making it possible for me to participate using Skype and thank all of you for your patience with this remote technology.

Jeff’s neurologists could not determine the cause of his stroke.  This is not rare.  Indeed, in 30 percent of stroke patients without a family history of stroke or unhealthy lifestyle habits associated with stroke, no underlying cause is ever found.

I know as a public health biologist that air pollution—particularly exposure to smog and traffic exhaust—is a known contributor to stroke risk. Smog and traffic exhaust—especially diesel exhaust–are also linked definitively to heart attack, lung cancer, bladder cancer, childhood asthma, cognitive decline among the elderly, and lowered birth weight among newborn babies.

When ground-level ozone—which is smog–and roadway exhaust increase, the rates of all those chronic diseases and disorders also invariably increase.  There is no doubt about that connection.

I also know as a public health biologist that drilling and fracking operations produce the kind of air pollution that is linked to all those problems that I just named.  So do the compressor stations required to push the gas through the pipelines.

And we also know that fracking-related air pollution can travel up to 200 miles, raising risks for public health far from the wells.

Jeff and I live only 45 miles from New York’s border with Pennsylvania where gas drilling is rampant.  Is it possible that fracking-related air pollution contributed to my husband’s stroke?  Well, yes, but I cannot not say so with any scientific certainty.  Stroke—like cancer, heart attack, and premature birth—lack what epidemiologists call “disease specificity,” which means that, because the disease can have many causes, we can rarely draw a causal connection between any one exposure and any one injured person.

The victims of air pollution—and there are 200,000 deaths from air pollution every year in the United States alone—are thus largely anonymous.

My point is this: the uncertainty of identifying the individual people harmed by fracking through toxic exposure does not mean that science is uncertain about the human health effects of the chemicals used and released by fracking.  Drilling and fracking operations and their infrastructure release to our common environment chemical contaminants that, for the most part, are very well described.

In addition to ozone and diesel exhaust:  Benzene. Arsenic. Radon. Diesel exhaust. Formaldehyde.  We know a lot about these contaminants and how they harm people.  The technology of  high-volume horizontal fracking may be new, but chemicals are old, and they include a lot of well-known villains.

For example, drilling and fracking makes smog.  Invariably.  We have good studies to show that.  Smog kills people.  Invariably. We have good studies to show that, too.  It is thus possible to connect the causal dots.

Another example: Drilling and fracking operations are loud. They produces industrial noise 24 hours a day for many months at a time at a decibel level that approximates jackhammers and helicopters.  We have good data to document that.  Continuous noise at that decibel level is linked to high blood pressure in adults and learning difficulties in children.  We have good data to document that, too.  In fact, the best data on the public health effects of noise pollution come from here in the EU.

In other words, to understand the public health impacts of fracking, we don’t need to enroll unconsenting people as subjects in an human experiment by unleashing drilling and fracking operations in their communities and then measuring the burden of disease 20 years hence. We can make very good predictions based on what we already know.

With that as my introduction, let me now briefly but more formally, mention some of public health threats that concern me most.  And here I’d like to say that I hope you can just sit back and listen.  I won’t be showing Powerpoint slides.  All of my remarks are drawn from studies and reports that have been compiled by Concerned Health Professionals of New York.  We are a group of doctors, nurses, and public health scientists who have created a clearinghouse of information on the health effects of fracking.  You can find all of our materials on the Concerned Health Professionals of New York website:

I want to return now to the shale itself and point out that all the gas-containing shale deposits around the world were once the floors of ancient oceans.  The bubbles of gas they contain represent the decomposed bodies of organisms that once lived in these seas:  sea lilies, squid, and plankton.  When these creatures died, they sank to the bottom and turn into gas.  These animals had no bones.  They are fossils that became invisible vapors rather than crunchy chunks of coal or oily ooze of petroleum.

In many places, these same sea floors also collected silt from eroded coastal mountain ranges, and this silt often included heavy metals such as mercury, which is known brain poison, and arsenic, which is known carcinogen, as well as radioactive substances, such as radium and uranium.

When drilling operations bore sideways, a kilometer or more, into these shale formations, they bring to the surface all of these toxic metals in the form of drill cuttings.  Radon gas, which is a radioactive gas, can also be released from these materials. This is the first public health menace I’d like to mention.  In the United States, drilling cuttings are commonly dumped in municipal landfills. I wonder if the directive in the European Union against the landfilling of heavy metals—which requires manufacturers to buy back end-of-life products that contain them—might be deployed in the fight against toxic fracking waste.

As for the fossilized gas bubbles themselves, they are more than just methane. They include other hydrocarbons, such as the known carcinogen benzene. Data from Colorado show us that volatile hydrocarbon gases are released from gas wells during the period of drilling, which can take many weeks and months to accomplish.  During this time, the well is not yet hooked up to a pipeline.  Each well is an open chimney that vents toxic gases into the air.  In some cases, carcinogenic benzene has been measured in ambient air at levels that are known to raise the risk for cancer at distances a kilometer or more from the wellhead.  In Pennsylvania, such fracking-related pollutants have been found at worrying levels in the air inside of people’s homes.

At other times during the life of a gas well, to control pressure or to prevent a catastrophic explosion, the gas is flared off.  This combustion creates other toxic byproducts, including formaldehyde, which is also a known carcinogen.  We already possess a lot of information about the public health effects of flaring operations and the public health effects of formaldehyde exposure.  Again, this is not an experiment we need to repeat with shale gas fracking.  We can make quantifiable predictions using models.

Meanwhile, down in the bedrock, the fractures created by the pressurized water must be propped open in order for the gas bubbles to be liberated.  Otherwise, once the hydraulic pressure is released, the cracks will close back up again.

In the United States, grains of silica sand are used for this purpose.  As the high-pressure water cracks the shale into pieces, it also blasts sand grains deep into the cracks to hold them open.  A grain of silica sand is round and structurally very strong and resistant to collapse even with a kilometer of rock and clay pressing down on it.

In the United States, the silica sand used for fracking is strip-mined along river valleys in Midwestern states.  The result is the devastation of farmland and the industrialization of rural communities along with the release of silica dust into air.  Crystalline silica, like asbestos, is a known lung carcinogen and is the sole cause of the progressive, disabling auto-immune disease called silicosis.

Recently, our federal government released warnings about the occupational health threats to workers in the gas fields exposed to silica dust at levels known to cause demonstrable risks for cancer and silicosis.  Even though we have good data on the impact of silica exposure on adult male workers, we have no data on the impact of silica exposure on children or pregnant women who live in areas undergoing industrial strip-mined for silica sand.  The default presumption should be that what causes cancer and disability among healthy adult workers cannot be good for four-year-old children, pregnant mothers, and elderly people with emphysema.

I am deliberately focusing here on the naturally occurring toxic materials that are released into the environment by fracking, rather than on the synthetic chemicals in the fracking fluid itself or on emissions of unburned methane from producing wells.  There is much talk in the United States about “green completion,”  “waterless fracking,” and the use of green chemistry in fracking fluids.  But even if fracking fluids could be made completely benign and safe (although they are not) and even if the methane leaks could be controlled, fracking inevitably releases into our common environment highly toxic materials that have been liberated from deep geological strata.

Digging a hole a kilometer deep and another kilometer sideways necessarily means unearthing from the ground and bringing to the surface, many thousands of radioactive materials, heavy metals, and toxic gases.  This can’t be regulated away.

I do want to say a few words about fracking fluid, however, and point out that it typically contains powerful biocides.  Biocides are all-purpose pesticides that are powerful poisons used to kill life forms.  Biocides are important ingredients in fracking fluid because they are used to kill subterranean organisms that live in the shale.

The gas-containing shale is not just a layer of inert rock.  It is a living ecosystem.  It a biosphere that extends into the dark heart of the planet.  The shale bedrock is home to ancient forms of life, including Archaea, fungus, and many forms of bacteria that form complex colonies.  Geologists now believe that by biomass—by weight—these deep life organisms that live far below Earth’s surface exceed the biomass of all the organisms that live on the sunlit surface.  If so, deep life organisms necessarily play an important role in the planet’s carbon cycle and, therefore, almost certainly, in climate stability.

Biocides in fracking fluid are needed to kill off these organisms because they grow inside the pipes and interfere with the flow of gas.  You can think of fracking as a form of massive underground pesticide spraying. We have no idea what the unintended consequences will be for us.

Finally, I wish to revisit a topic dealt with by Josh Fox with so much elegance and cinematography: the material known as cement.

Cement well casings form the only barrier between the many toxic chemicals that naturally occur in the shale—along with the many others that are ingredients of fracking fluid—and the drinking water aquifers that lie above.  Because the fractures in the shattered shale are held permanently open by grains of sand or other proppants, whatever toxic vapors the rock had held will for all eternity have underground pathways along which to travel.  The cement well casings prevent the gases from reaching the groundwater aquifers.  And they must do so forevermore.  But cement is not immortal.  With time, it cracks, shrinks, and crumbles.  Our best data show us that the failure rate of well casings increase with time, with more than half of all well casings leaking after three decades.

These findings raise important ethical questions of generational inequity. Groundwater, once contaminated, cannot be purified by any known technology. Are those profiting economically from fracking laying public health time bombs under the earth for future generations who will experience none of the temporary, pollution-generated prosperity that is promised by the shale gas revolution?

To conclude: the history of environmental public health shows us that some practices and technologies—lead paint, DDT, and asbestos, to name a few—are inherently dangerous and unmanageable.  No regulations could solve the problems so created. Instead, abolition was the answer.

Shale gas extraction via fracking shows signs of being an inherently dangerous, unmanageable practice.  Fracking can’t be tested in a laboratory.  Nor do we have another planet to try it out on.  Of course, new science is always needed to fill in the data gaps, but science is slow and, while the wheels of scientific proofmaking grind slowly on, people should not be placed in harm’s way.  Because the risks created by fracking include permanent, unfixable ones, because fracking and its infrastructure uses farmland, villages, and suburban communities as its factory floor, public health scientists have a moral responsibility to act on the science that we already possess and insist on precaution rather than cooperate with the creation of new sacrifice zones.

Again, the organization is Concerned Health Professionals of New York.  The website is

Merci.  Vielen Dank.  Thank you to both my audience and to my neighbor, Marilyn, who provided me from her garden these sunflowers that sit behind me.  Sunflowers are both a symbol of the European Greens and the promise of solar power, which has not, to my knowledge, ever contaminated anyone’s drinking water.