Four Fatalities Linked to Used Fracking Fluid Exposure During
‘Flowback,' NIOSH Reports
Daily Environment Report
By Robert Iafolla
May 19 — Initial government field studies on hydraulic fracturing
operations suggest that workers could be exposed to hazardous
levels of volatile hydrocarbons from used fracking fluids, the
National Institute for Occupational Safety and Health said May 19.
At least four workers have died since 2010, apparently from acute
chemical exposures during flowback operations, which involve
transferring, storing and measuring fluids that return to the
surface after fracking, NIOSH said in a blog post.
The institute assessed worker exposure to other chemicals mixed
into fluids that are injected into the earth during fracking, said
Max Kiefer, director of NIOSH Western States Office.
Those findings will be detailed in later publications,
including a peer-reviewed case study this summer, Kiefer said.
“But right now, the exposures of concern from a worker standpoint
are from endogenous hydrocarbons that can be emitted from returned
flowback fluids, not from other chemicals,” Kiefer told Bloomberg
BNA May 19.
NIOSH highlighted how little is known about the potential health
hazards associated with fracking, such as chemical exposure, in
contrast to the well-developed knowledge about safety hazards from
accidents common to oil and gas extraction.
Fracking operators mix silica sand and chemicals into water, which
is injected underground to fracture shale formations. The liquid
mix is removed and the sand remains in the broken shale, acting as
a “proppant” to keep the fractures open and allow oil or natural
gas to flow. The liquid that flows back can contain volatile
hydrocarbons picked up from the shale formations, NIOSH found.
More Study Needed
The institute has studied the health hazards of silica exposure
at fracking well pads, but its research thus far into flowback
operations is far less comprehensive, Kiefer said.
Researchers would like to look at different types of shale
formations, climactic conditions, factors that led to exposure and
other variables, he said.
NIOSH asked oil and gas companies and other stakeholders to help
further characterize risks associated with flowback operations, as
well as to assist with developing and implementing exposure
controls as necessary.
Kiefer said reports from media sources and the Occupational Safety
and Health Administration about fatalities triggered the research
into flowback operations. Some of the fatality investigations are
incomplete, but thus far the workers likely were gauging flowback
or production tanks, or transferring flowback fluids, NIOSH said
in the blog post. The workers, who were located at well sites in
the Williston Basin in North Dakota and Montana, often died when
Risk to a Temporary Workforce
Dan Neal, director of Equality State Policy Center in Wyoming,
said health hazards pose a particular risk to fracking
workers—known as roughnecks—because the work is temporary, and the
worksites are transient.
A roughneck could get sick after work with a company has finished,
plus it could be difficult to establish a causal connection
between exposure at a particular site and an illness, Neal said.
These factors could conspire to make worker compensation
impossible to obtain, he said.
“Roughnecks are sort of your ultimate temp worker,” Neal told
Bloomberg BNA May 19. “Fracking doesn't fit the traditional
employment model, which is what safety and health regulations are
Moreover, Neal questioned whether health hazards from chemical
exposure is something the industry has examined.
Safety and health is important to oil and gas companies said
Shawn Bennett, a spokesman for Energy in Depth, a research and
advocacy organization launched by Independent Petroleum
Association of America.
Many oil and gas operators and contractors are involved with OSHA
in the National Service, Transmission, Exploration and Production
Safety Network, which looks for opportunities to improve
environmental, safety and health issues, Bennett told Bloomberg
BNA May 19.
To contact the reporter on this story: Robert Iafolla in
Washington at firstname.lastname@example.org
To contact the editor responsible for this story: Jim Stimson at
The NIOSH blog post on flowback operations is available at http://blogs.cdc.gov/niosh-science-blog/2014/05/19/flowback/