A new study discovered a link of the proximity of fracking to higher household concentrations of radon gas, the second leading cause of lung cancer in the U.S.

Between 2007 and 2014 when scientists measured and geocoded data from 118,421 homes across all 88 counties in Ohio, they discovered that closer distance to the 1,162 fracking wells is connected to higher indoor radon concentrations.

Distinguished University Professor and Chair of the UToledo Department of Civil and Environmental Engineering, Dr. Ashok Kumar said that the shorter the distance home is from fracking well, the higher the radon concentration. The larger the range, the lower the radon concentration.

Also, the researchers discovered the average radon concentrations among all tested homes across the state are higher than safe levels outlined by the U.S. Environmental Protection Agency and World Health Organization standards. 5.76 pCi/I is the average while the EPA threshold is 4.0 pCi/I. The postal code 43557 in the city of Stryker has the highest radon concentration at 141,85 pCi/I for this data set.

The UToledo Department of Geography and Planning Dr. Yanqing Xu said that they care about air quality. Their motivation is to save the lives of Ohioans. Xu hopes this eye-opening study inspires families across the state to take action and have their homes tested for radon and, if needed, install mitigation systems to protect their loved ones.

Since it cannot be smelled or seen, radon begins as uranium found naturally in soil, water, and rocks, but transforms into gas as it decays. Fracking or drilling the rock formation via hydraulic fracturing stimulates the flow of natural gas. In Ohio, natural gas is available in deposits of the ancient Marcellus and Utica shales.

The eastern part of Ohio is where most fracking wells are located, while Athens County has the highest number of fracking wells with 108. Fulton County is the only county with more than 20 fracking wells in western Ohio.

The researchers used data from the publicly accessible Ohio Radon Information System (ORIS), which the UToledo Department of Civil and Environmental Engineering started developing more than 25 years ago and maintains to improve public knowledge about indoor radon concentration. Licensed testers collect data each year in basements and first floors of homes in Ohio's 1,496 zip codes.

Kumar noted that it is easy to find the average radon concentration in the zip code on the website. After testing her home with a $10 kit, Xu, a health geographer who previously studied obesity, installed a radon mitigation system.