Fracking-a technique where high-pressure water is aimed at shale rock to extract the gas inside-releases high levels of PAHs (polycyclic aromatic hydrocarbons) into the atmosphere, say researchers from Oregon State University.
The researchers began their investigations after they had been approached by a group of residents in Carroll County, Ohio, where there is a deep formation of shale and is a 'hot-spot' of natural gas prospecting. The residents were all concerned about the impact of the drilling on their health.
The researchers set up boxes that measure air quality in gardens close to drilling sites and up to three miles away. Not surprisingly, those closest to the wells also had the highest levels of PAHs, but even the lowest levels were still 10 times higher than in Michigan, where there is no fracking. All the levels are considered unsafe according to the Environmental Protection Agency.
(Source: Environmental Science & Technology, 2015; 49(8): 5203)