Increased radon levels traced to fracking

Hydraulic fracturing, commonly known as fracking, has become a controversial subject in recent years as it becomes a more and more common way to dredge natural gas and petroleum out of the ground. However, the process may not be safe for people who live near the fracking sites. A recent study by researchers at the Bloomberg School of Public Health has suggested that increased levels of radon in homes in Pennsylvania are related to the onset of fracking in the area.

The oil and natural gas that we burn today began as plants and animals living in the oceans millions of years ago. As part of their life process, they absorbed energy from the sun and stored the energy in their bodies as carbon. When they died, they settled onto the ocean floor, and as the process continued, layers of sediment and plant and animal remains formed.

As the layers built up, tremendous weight caused an increase in pressure and heat. Depending on the levels of these conditions, oil or natural gas formed. Some escaped into the water and atmosphere; however, some was trapped between layers of impervious rock, forming the deposits of oil and natural gas that is drilled for today.

Oil and natural gas can be found in large quantities in geologic formations. After the extraction of the initial deposits, the rate of flow can reduce due to decreased permeability or damage and clogging from the process of drilling.

Enter fracking.

Hydraulic fracturing is a method that recovers oil and gas from wells that have been deemed non-producers. This can be in areas where it is difficult to reach the oil or in areas that have been damaged during the process of drilling. During the past decade, fracking has revived shale deposits throughout the United States and turned them into productive sites.

The process of fracking is employed after a well has been drilled and steel pipe, called casing, has been inserted into the resulting hole. Regions that contain oil or gas along the casing are identified, and the casing is subsequently perforated at those locations. Fracking fluid is then injected into the well and flows into the target zones. Pressure is increased and causes the formation to crack or fracture, liberating the trapped deposits of oil and natural gas.

In addition to large volumes of water, a variety of chemicals are used to make fracking fluids. Fracturing fluid chemicals are known to be toxic to humans and wildlife and several are known carcinogens. Very low amounts of some fracking chemicals are capable of contaminating millions of gallons of water.

A number of major companies use fracking, including ExxonMobil and BP, and the practice is exempt from most environmental laws.

Humans can be exposed to the chemicals involved in fracking in several different ways. Chemicals can enter the supply of drinking water, people can breathe the vapors, or they can come in direct skin contact. Also, soil and surface waters have been contaminated from spills of fracturing chemicals and wastes during transportation.

One of the more dangerous chemicals from fracking is radon, a colorless and odorless gas that can cause lung cancer. The Surgeon General reports that it is actually the second leading cause of lung cancer, with the first cause being smoking.

Radon is generated by the natural breakdown of uranium in soil and rock. In the environment it dissipates into the atmosphere; however, when it is trapped in homes after leaking into basements, it can be deadly.

Over the past eight years, 7,469 fracking sites have been created in Pennsylvania. To investigate their effect on radon levels in homes, Bloomberg researchers pored through radon measurements logged in the Pennsylvania Department of Environment Protection database. Most of the data came from measurements taken when houses are bought and sold. To be thorough, the researchers, led by Dr. Brian Schwartz, an environmental health sciences professor, looked at 24 years’ worth of data.

After analysis, the scientists found that houses using well water have a 21 percent higher radon concentration than houses using municipal water. This could be caused by fracking occurring near the wells. They also found that homes in rural and suburban areas have 39 percent more radon than homes in cities, which they suggest could be because rural and suburban homes are typically closer to fracking sites.

These conclusions suggest that something worrying might be happening, but the researchers still don’t know exactly why radon is more plentiful in fracking areas. Joan Casey, the study’s lead author, suggests that fracking may have changed the geology of the ground and created a way for radon to leak into the air.

On the other hand, she suggests that another possibility is that houses in Pennsylvania have actually become too sturdy — as sealant methods have gotten better, more radon could be trapped inside.

Although there are no definite conclusions yet, it seems clear that as fracking sites multiply across the United States, scientists will have to take a harder look at their effect not just on the environment but also on human health.