Very little attention is paid to working conditions on fracking sites. And though there remains a lack of conclusive evidence for the potential health effects resulting in communities that live in close proximity to shale gas operations, various claims are widely circulated by organizations and news media outlets. But we’re curious as to how fracking affects those citizens who actually migrate from site to site – the workers constructing and stimulating oil & gas wells, who must transport and work with fracking fluid chemicals and sand. Obviously, the effects on workers will be very different from the effects on nearby residents because workers do not live near the sites after the completion of each fracking operation.
Airborne silica dust
When workplace safety & health experts first visited fracking sites to examine the health effects of chemical exposure on workers, they were surprised to discover a separate, unprecedented health risk altogether. In 2010-2011, when the NIOSH (National Institute of Occupational Safety and Health) tested the breathing air at 11 fracking sites in 5 different states – Colorado, Arkansas, North Dakota, Pennsylvania, and Texas – they found that the concentrations of silica often far exceeded permissible exposure limits (PEL). Silica is crystalline quartz, and composes a large part of the sand used as the “proppant” in a fracking job. That is, the silica particles pumped into a well with the fracking fluids help keep the fractured rock cracks open to facilitate the free flow of oil and gas up the wellbore. It’s an indispensable part of the process. However, the silica dust generated during the process of moving and handling the sand is hazardous to breathe. Prolonged exposure to frack sands is known to cause silicosis (a disease that scars and inflames the lungs) as well as increasing the risk for scleroderma, lung cancer, bronchitis, renal disease, and respiratory failure.
The dangers of inhaling silica is no new discovery. Long experienced in other industries such as mining, manufacturing, and construction, the federal government (specifically the Office of Informational and Regulatory Affairs) has been in the slow process of setting industry-wide, national controls on silica. But it seems the new rules have been stalled, even after NIOSH released its study and partnered with the Center for Disease Control to issue a “hazard alert” in June 2012 about dangerous levels of silica at frack sites. Industry lobbies claim that the new rules will make operations more expensive and that current standards are sufficient to protect workers.
Level of exposure
A single frack job uses between several tons and two million pounds of sand, enlaced with silica, not only in well stimulation but sometimes the cementing process too. Nearly 28 million metric tons of silica sand were used in US shale gas operations in 2012. Also, over 200,000 people work on site with the sand. How is the risk generated? When the silica gets blown around on-site:
Overall, the study found seven points of dust generation that were common at all 11 sites: from “thief hatches” on the tops of sand movers during filling, from the sand mover belt, from the momentum of falling sand below the dragon tail at the blender hopper, from transfer belts when sand is deposited onto the belt and conveyed to the blender, from sand leaving the end of the dragon tail, from fill ports of sand movers during refilling operations, and from truck traffic at the fracking site. (Bloomberg BNA)
Over 100 air samples on-site were tested; 79% of the samples exceeded recommended exposure limits and well over half exceeded the permissible exposure limits (PEL) set by related health agencies. Sometimes silica concentrations were measured at 10 times OSHA’s exposure limit. Workers often accidentally inhale the silica particles as they move and refill the sand-movers, and long exposure can make it difficult to breathe over time. According to the Center for Effective Government, between 180-360 new cases of silicosis are reported every year. OSHA (the Occupational Safety and Health Administration) estimates that if appropriate limits are placed on workers’ exposure to crystalline silica, up to 60 lives could be saved yearly from respiratory diseases.
Addressing fracking workers’ health risks
Many companies provide air purifying respirators for workers, but the masks typically worn do little to protect employees from current levels of silica concentration at the drilling sites. However, other precautions are in the mix: watering down the roads in order to prevent the sand from blowing around, closing hatches on sand-moving machines, erecting warning signs about health risks at sites, and attaching vacuums to machines to suck up the dust. Industry officials complaining about forthcoming rules about fracking sand should take note of companies in North Dakota’s Bakken shale play, where none of the 10 air samples collected exceeded OSHA’s PEL because companies use less silica and more ceramic in their frac-sand. Alternative products, besides ceramic beads, include small metal aluminum beads and are equally efficient as proppants. Engineering controls have also been established in other industries that have been forced to adapt practices to meet exposure limits.
Very little is still known – or supported by substantive evidence – about the health risks associated with fracking fluid chemicals. But these studies, and the combined insights of multiple health agencies (OSHA, AFL-CIO, American Conference for Industrial Hygienists, NIOSH, and the CDC), confirm that workers who remain with the fracking industry and move from site to site are at greatest risk for respiratory and lung diseases. Controls on silica concentration in fracking sands may soon help to reduce health risks and improve working conditions at shale gas drilling sites.
Read OSHA’s fact sheet for more information on silica as well as silica-related health risks across the industrial sector. The organization is serious about helping employers cheaply assess the risks of silica and find alternative products; they are even designing an iPhone and Tablet app that ”helps employers identify respiratory hazards, recommends a product and helps users perform fit tests.”