Sand dust created from the hydraulic fracturing to extract natural gas from rock is one of the most dangerous threats to workers at wells blossoming across the U.S., a government safety researcher said.
About four out of five air samples from well sites in five states in the past two years exceeded recommended limits for silica particles, said Eric Esswein, an industrial hygienist at the National Institute for Occupational Safety and Health. The particles in sand dust created during the so-called fracking process can lodge in the lungs and cause potentially fatal silicosis, he said today at a conference sponsored by the Institute of Medicine.
Drilling companies and their workers do a better job handling potentially toxic chemicals than they do sand dust, for which “there’s really no inherent protection” at well sites, Esswein said. Fracking involves pumping millions of gallons of chemically treated water and other matter underground to break up rock and free sources of natural gas.
“There’s lots more sand used these days in fracking operations than there was 10 or 15 years ago,” Esswein told an IOM panel that is studying health issues related to fracking.
The gas industry says that its wells, sometimes blamed by people who live nearby for air and water contamination, are safe for both workers and the communities where they drill.
“When it comes to claims that hydraulic fracturing is causing people to get sick more frequently or more severely, the data simply do not support that conclusion,” said Steve Everley, a spokesman for Energy In Depth, in an e-mail. His group advocates for drilling-friendly policies on behalf of gas companies including Oklahoma City-based Chesapeake Energy Corp.
Focus on Safety
Workers at gas wells are generally safer than in other businesses, Everley said, pointing to U.S. Bureau of Labor Statistics data that show the incidence of non-fatal injuries in the oil and gas extraction industry is less than half the national average.
Esswein, whose agency is part of the Centers for Disease Control and Prevention, said his team spent about 225 hours visiting 11 well sites in Colorado, Arkansas, Pennsylvania, Texas and North Dakota in 2010 and 2011, with the consent of drilling companies, to examine safety practices.
Workers were careful while handling dangerous chemicals and generally knew what to do in the event of emergencies, he said.
“There’s a big focus on safety” at well sites, Esswein said. “There isn’t as much emphasis on health. We call it big ‘S’ and little ‘H.’”
He took air samples from workers and near wellheads, to test for contaminants, and found elevated levels of silica most places. In about one-third of the samples, he said, silica levels were more than 10 times recommendations.
Esswein said he didn’t know whether the sand dust may be harmful to local residents because his team didn’t take measurements at the edges of well sites. He plans to publish data from his survey in trade and scientific journals this year.
The Institute of Medicine, a branch of the National Academy of Sciences, advises the U.S. government on health topics.