DALLAS (CN) - Watchdogs claim that toxic benzene found in the air at several playgrounds in the Barnett Shale in Texas exceed long-term exposure limits imposed by the state, adding fuel to a looming vote on a proposed fracking ban.
ShaleTest.org, an independent nonprofit that performs air and water tests near drilling sites, announced Monday the results of air tests performed at McKenna Park in Denton, several parks and playgrounds in Mansfield, Trinity Park and Delga Park in Fort Worth and Dish City Park in Dish.
Fracking, also known as hydraulic fracturing, is the practice of drilling and injecting the ground with highly pressurized fluid, breaking shale rocks to release natural gas.
The report concluded that at the Denton, Dish and Fort Worth sites, the levels of benzene - a known carcinogen - exceeded effects screening levels and air monitoring comparison values imposed by the Texas Commission on Environmental Quality.
"Benzene has been linked largely to leukemia and cancers of other blood cells," the report states. "Benzene can also cause excessive bleeding and can affect the immune system, increasing the change for infection.
The levels of propene at the Mansfield site and xylenes at the Dish and Fort Worth sites also exceeded the TCEQ's permissible limits.
"Xylenes can cause developmental effects on unborn children, and has been associated with low birth weight or size, and learning disabilities," the report states. "Propene is a flammable gas that can cause lung irritation and asphyxiation at higher concentrations."
The report notes that the TCEQ's standards are set for occupational exposure by adults for 40-hour work weeks.
"There has been little progress in development of standards applicable to children and others exposed 24 hours a day, 7 days a week," the report states. "The TCEQ ESLs and the AMCVs only establish standards for individual compounds, and do not consider synergetic effects of the compounds. In other words: they do not consider the potential that the health effects of exposure to combinations of certain compounds may be more significant than the simple addition of the effects of individual compounds. Research on exposure to multiple chemicals from oil and gas facilities is just beginning. Therefore, it is important for parents and decision makers to be aware of all of the potential health effects of chemicals released by natural gas development activities."
ShaleTest president Tim Ruggiero was critical of the oil and gas industry for claiming they are drilling responsibly.
"These tests show they're not," he said in a statement.
"Although emerging science confirms that fracking-related air pollution is a health risk, there's no agreement yet on 'how close is too close'," ShaleTest director Calvin Tillman said. "These results suggest that sometimes 'miles away' can be too close."
Denton voters will decide on imposing a fracking ban in November.
Cathy McMullen, Denton Drilling Awareness Group president, urged residents to support the ban after the release of the report.
"The City of Denton promised us air monitoring," she said in a statement. "But we'd never have known about toxic benzene at McKenna Park violating the TCEQ long-term exposure limit if it hadn't been for independent testing. After years in pursuit of responsible drilling with industry, and state and city government, we now know from personal experience that responsible drilling is a sham."
ShaleTest plans to hold community meetings in the cities of the testing sites.
"We aim to promote action and further investigation by the public health community," the report states.
In April, a jury in neighboring Dallas County awarded a Decatur family $3 million from Aruba Petroleum in what is believed to be the first verdict of its kind finding injuries from fracking.
That lawsuit, filed in 2011, alleged that the release of hazardous gases, chemical and industrial waste from nearby fracking made the family sick, killed pets and livestock, and hurt quality of life on a 40-acre ranch.
Aruba argued at trial that it complied with air quality and drilling safety guidelines set by the Texas Railroad Commission and TCEQ.
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