What do 17 dead cows, seven stillborn puppies, an anorexic horse, and a delirious child have in common?

Unfortunately, there's no punch line to this one.  According to research published recently in New Solutions, a peer-reviewed journal that focuses on environmental and occupational health policy, they're all suspected casualties of drilling for natural gas.

As we described in previous posts, a range of health risks have been associated with hydraulic fracturing and other parts of the extraction process, such as the chemicals that are injected deep underground and the natural, but toxic, compounds that rise to the surface.  Industry-friendly policies, however, have prevented high-quality public health studies that are needed to accurately measure the impact. The missing research, in turn, stymies regulatory policies to protect the public's health.

Lacking sufficient data to conduct an epidemiological investigation, the authors of the dead-cows study (veterinarians Michelle Bamberger and Robert  Oswald, who is on the faculty at Cornell University) reviewed 25 recent cases where health problems among animals, and their owners, were suspected of being linked to natural gas drilling.  They interviewed animal  owners in six states affected by gas drilling: Colorado, Louisiana, New York, Ohio, Pennsylvania, and Texas. Since many of the individual cases are in litigation, however, details about who, where, and when are omitted from the published article.

Nevertheless, they make for compelling reading:

In one  case, fluid used in hydraulic fracturing was accidently released into a cow pasture—apparently killing 17 otherwise healthy cows in one hour. (The industry frequently points out  that such fluid is 99.5% water and sand ... )

Another case describes a series of events at two homes that were exposed to a large amount of natural gas drilling wastewater.  First, a horse suddenly developed "anorexia" and neurological abnormalities, and died of liver failure.  Then a dog, having previously delivered three healthy litters, birthed a fourth in which one puppy was stillborn and another had a cleft palate. In her fifth litter, seven puppies were stillborn and an eighth died with 24 hours; some were hairless. Last was a child, who began to suffer fatigue, severe abdominal pain, confusion, and delirium.  After the child was hospitalized, a toxicology test revealed arsenic poisoning.

And then there is the natural case-control cow study: A farmer had three different pastures of cattle in an area with intense natural gas drilling. In each pasture, the cows drank from a different water source—60 from a creek, 20 from hillside runoff, 16 from a pond.  Over a three-month period, 21 of the cows that drank from the creek suddenly died. Of the 39 the creek-drinking cows who survived, 16 failed to reproduce that spring and many had calves that were stillborn or had abnormalities such as eyes with unmatched colors.  The health of the cattle in the other two pastures was unaffected.

The report presents many other cases.  As the authors clearly state, the observational study  lacks the scientific rigor of controlled experiments or robust epidemiological research.  While the cases presented are largely anecdotal, the study provides the most comprehensive account to date of the health impacts of natural gas drilling (previous studies have focused on environmental impacts—a related, but different question).

As acknowledged by scientists at the Centers for Disease Control and Prevention, much more research is needed to make a case that natural gas drilling causes public health problems.  That means, of course, that such research actually needs be conducted—a process that could be  aided by laws mandating  the full disclosure of chemicals used under all circumstances, and by regular testing of water, air, and soil before, during, and after the extraction takes place.

Scientific research often takes years to establish cause  and effect, and government routinely acts to protect the public's health when many people potentially could be harmed while waiting. Indeed, we all make decisions based on anecdotal evidence. I took an umbrella to work on Wednesday because it looked cloudy and felt like rain.

I didn't want to wait for peer-reviewed weather data—or a  soaking.

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