Radon gas detected in Pennsylvania homes is likely linked to fracking operations in the area, a new study reveals.
Fracking, also known as hydraulic fracturing, is utilized to extract petroleum and natural gas from wells which would normally be considered dry. The process involves drilling into the deposit, and injecting a mixture of water, sand and other chemicals into the hole at high pressure, to fracture surrounding rocks and release hidden fossil fuels.
Radon is a colorless, odorless gas which is the second-leading cause of lung cancer globally, behind tobacco use. The chemical can be produced from the decay of radium-226 released along with natural gas deposits. Well water and air can also carry the radioactive element.
Johns Hopkins Bloomberg School of Public Health researchers examined 860,000 radon readings taken in Pennsylvania homes between 1987 and 2013. Many of these readings came from mandatory measurements taken during home sales.
Analysis revealed a significant increase in concentrations of the hazardous gas beginning in 2004. That was the year that fracking became more common in the Keystone State, resulting in the production of 7,469 unconventional wells statewide. Prior to 2004, little difference in radon levels was seen between counties. Starting that year, readings were higher in areas where fracking became common than in locations where the practice was rare. Pennsylvania is the No. 2 producer of natural gas after Texas, pumping 3,259,042 million cubic feet of natural gas in 2013, according to the Energy Information Administration.
"One plausible explanation for elevated radon levels in people's homes is the development of thousands of unconventional natural gas wells in Pennsylvania over the past 10 years. These findings worry us," Brian Schwartz from the Department of Environmental Health Sciences at the Bloomberg School said.
Homes in rural regions where most fracking takes place were found to have an average radon concentration 39 percent higher than those in urban areas. Radon was 21 percent higher in homes using well water than those on municipal systems. Statewide, 42 percent of radon readings were greater than levels deemed safe by federal officials.
Study author Joan A. Casey says it is unclear whether the excess radon in houses is coming from radium getting into well water through the fracking process, being released into the air near the gas wells or whether natural gas from shale contains more radon than conventional gas and it enters homes through cooking stoves and furnaces.
Another possibility, Casey says, is that buildings have been more tightly sealed in the past 10 years, potentially trapping radon that gets inside and leading to increased indoor radon levels. In the past, most radon has entered homes through foundation cracks and other openings. Casey is a Robert Wood Johnson Foundation Health & Society Scholar at the University of California-Berkeley and San Francisco who earned her Ph.D. at the Bloomberg School in 2014.
"By drilling 7,000 holes in the ground, the fracking industry may have changed the geology and created new pathways for radon to rise to the surface," Casey says. "Now there are a lot of potential ways that fracking may be distributing and spreading radon."
The Technologically Enhanced Naturally Occurring Radioactive Materials Study (Tenorm) conducted by the Pennsylvania Department of Environmental Protection (DEP) also examined concentrations of radon at 34 gas wells. That study found no danger to the public from the practice of fracking.
"Nearly 1 out of every 15 homes in the U.S. is estimated to have elevated radon levels. Elevated levels of radon gas have been found in homes in your state... While radon problems may be more common in some areas, any home may have a problem. The only way to know about your home is to test," the Environmental Protection Agency states.
Analysis of radon concentrations in Pennsylvania homes and how they may be affected by fracking was detailed in Environmental Health Perspectives. State environmental regulators plan to review the study in detail, according to DEP spokeswoman Susan Rickens.
Photo: Credo Fracking | Flickr
