The Hazards of Chemicals Used in Hydrofracking
Tom
Shelley
“This
stuff is so safe you can drink it”—or so the gas drilling industry would like
us to believe. They also compare
chemicals used in high-volume, slick-water hydrofracking
processes to those found in common household cleaners. Indeed, some small set
of those hazardous materials are found in some household products, although
many are not. Those that are, often are accompanied by poison control labels.
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Top: Chemical transport trucks on a drilling site. Photo: NYS Department of Environmental Conservation. Just above: A 2007 hydraulic fracturing operation on a Marcellus Shale gas well showing the number of trucks involved. Photo: US Geologic Survey |
It
is estimated by the DEC that 9 to 35 percent, or about 90,000-350,000 gallons
per million gallons used, of fracking fluid immediately
comes back out of the ground in the form of “flow back” water. Over time, a
similar amount of “produced water” is delivered to the surface with the gas
produced by the well. This produced water contains some of the fracking chemicals and is further contaminated by heavy
metals and radioactivity, along with compounds that are formed by the interaction
of the fracking fluids in the hot underground environment
with the natural materials in the rock itself. Large amounts of strong salt
solutions (brine) are also components of the produced water. These contaminated
brines are difficult to
dispose of safely.
These
fluids are typically stored in ponds near the well pads until they are transported
to treatment facilities or off-site storage, such as injection wells. The ponds
have leaked and contaminated soil and surface water around the ponds. Volatile
organic compounds (VOCs), many of which can cause moderate to
severe health problems, evaporate from the ponds before the contaminated
water can be removed for processing or off-site storage.
Almost
all “flow back” and “produced water” would be
classified as hazardous industrial waste if the gas industry were regulated
as thoroughly as other chemical-intensive industries. Unfortunately, the
industry has a long history of NOT being regulated under federal RCRA (Resource
Conservation and Reclamation Act) or state hazardous waste regulations. The
health of the communities around natural gas drilling suffers due to of this
lack of regulation.
Chemicals and compounds of concern
Here
are some of the more commonly used hazardous materials of concern found in the
products used in the fracking process:
Benzene and
other aromatic hydrocarbons such as toluene, ethylbenzene
and xylene (BTEX). These volatile organic
compounds (VOCs) are widely found in gasoline, petroleum distillates, diesel
fuel and other petroleum-based products that are or have been in the past used
in the fracking mixtures.
Polyaromatic hydrocarbons (PAHs) are larger molecules
made up of benzene building blocks. All of the above compounds are found in
produced water as well as some of the fracking
mixtures.
The
BTEX suite of hydrocarbons are known carcinogens (leukemia), cause damage to
the liver, central nervous system (narcotic effects) and other organs, may
cause damage to fetuses, and may cause genetic changes, as well as being
irritants of the skin.
Formaldehyde is a gas, used in an
aqueous
solution. It is used in low concentration, but is very toxic and dangerous
even at these low concentrations. It is used as a biocide along with many other
very hazardous chemicals. It is a known carcinogen, a severe irritant (eyes,
skin, lungs), a systemic poison, and will cause an allergic reaction with repeated
exposure.
1,4-Dioxane causes damage to the
central nervous system, liver and kidneys. It is toxic, an irritant, and also
a probable carcinogen.
Heavy
metals—arsenic,
barium (dissolved), cadmium, chromium, cobalt, lead, molybdenum, nickel,
selenium, silver, strontium, thallium—are found in both the “flow back” water
and the “produced water.” Some are components of the fracking
chemicals, and others are from the shale itself.
2-Butoxyethanol is readily absorbed by skin or by
inhalation. It is an irritant, causes central nervous system effects, may
damage the liver, kidneys and lungs, and is a suspected carcinogen. It is also
a known endocrine disruptor with effects noted at extremely low concentrations.
There
are dozens of other hazardous materials in use in the fracking
“chemistry” and the byproducts of the fracking
process, all of which can cause serious individual or public health problems if
allowed to enter our air or water. We have seen serious instances of such
problems in various Western
states and close by, very recently, in Pennsylvania.
Tom Shelley is a chemical safety and hazardous materials specialist in Ithaca, New York.
For more information on hydrofracking chemicals and health effects, check out Dr. Theo Coburn’s work with The Endocrine Disruption Exchange at endocrinedisruption.com.