Surfactant chemicals analyzed in samples of fracking fluid collected in five states were no more toxic than common household substances such as toothpaste, laxatives and detergent, according to an analysis by researchers at the University of Colorado Boulder.
The study, published in the journal Analytical Chemistry, identified surfactants found in fracking fluid samples from Colorado, Louisiana, Nevada, Pennsylvania and Texas. Surfactants are used to reduce the tension between oil and water and extract more oil from porous rock.
The chemicals found in the samples are the same that most people are putting down our drains at home, said Michael Thurman, lead author of the paper and co-founder of the Laboratory for Environmental Mass Spectrometry in CU-Boulder’s College of Engineering and Applied Science. The lab is sponsored by Agilent Technologies.
The number of natural gas wells in the US has increased by 200,000 in the last 20 years, according to the US energy Information Administration. Techniques such as hydraulic fracturing, or fracking, have driven that growth.
The fracking boom has led to concerns that chemicals used in the fracking fluid cause contamination. Determining the risk of contamination has been difficult because oil and gas companies have reluctant to share exactly what is in their proprietary fluid mixtures, according to CU-Boulder. Companies can adhere to state and federal disclosure laws by using broad chemical categories to describe the actual ingredients.
The researchers say the new study is important because it provides a picture of the possible toxicity of the fluid. A detailed list of ingredients can also be used as a fingerprint to trace whether suspected contamination of water supplies actually originated from a fracking operation.
The authors warned that their results may not be applicable to all wells because individual operators use unique fracking fluid mixtures.
The fluid samples analyzed for the study were provided through partnerships with Colorado State University and colleagues at CU-Boulder.
A Duke University study released in September found defective wells, not hydraulic fracturing, is the primary cause of water contamination from shale gas extraction in parts of Pennsylvania and Texas.
Data showed that contamination stemmed from well-integrity problems such as poor casing and cementing, which rules out the possibility that methane migrated up into drinking water aquifers because of horizontal drilling or fracking.
Photo Credit: oil drilling via Shutterstock