People living near fracking sites have reported health problems for years, with symptoms ranging from respiratory ailments to birth defects. But because air and water quality are often not monitored near fracking sites, surprisingly little is known about the overall public health impacts of the gas drilling process. To help fill the knowledge gap, a new study explores air quality at fracking sites across several states and finds numerous instances of toxic chemicals above national safety standards.

Coming Clean and Global Community Monitor conducted the air quality study in six states – Arkansas, Colorado, Ohio, Pennsylvania, New York, and Wyoming. It is the first peer-reviewed study on air pollution from fracking that uses samples from multiple U.S. sites.

Breathing Toxic Air

Local residents collected air samples near fracking wells and production pads, as well as wastewater pools and processing stations. (In New York, for example, samples were collected near compressor stations on natural gas pipelines, as the state currently has a moratorium on fracking.)

An accredited laboratory analyzed the samples for the presence of nearly 100 toxic chemical compounds, with alarming results. Twenty-nine out of 76 samples analyzed (38 percent) found toxic chemicals at levels that exceed federal health and safety standards. Those chemicals included:

• Hydrogen sulfide, a deadly gas that has killed oil workers in the field
• Formaldehyde, a known cancer-causing substance
• Benzene, also known to cause cancer
• 1,3-butadiene, a skin and eye irritant that can also effect the neurological system
• Toluene, which can cause neurological effects
• Ethylbenzene, which can affect development
• Mixed xylenes, which can bring on headaches and respiratory problems
• N-hexane, which is found in crude oil and is capable of causing neurological and reproductive issues

In Wyoming, seven sites tested positive for hydrogen sulfide at levels two to 660 times what the U.S. Environmental Protection Agency (EPA) considers life-threatening.

In Arkansas, seven samples tested positive for formaldehyde at levels up to 60 times what EPA classifies as cancer-causing.

Two other states also had chemicals at levels exceeding these standards, including hydrogen sulfide in Colorado and formaldehyde and benzene in Pennsylvania.

The study noted that chemical exposure thresholds are usually based on the healthy working male population. Vulnerable populations – such as children, pregnant women, and those with respiratory diseases – may experience symptoms at lower exposure levels. Given the close proximity of some of these drilling operations to residential areas and schools, vulnerable populations could easily be at risk. Furthermore, only a fraction of the thousands of chemicals in use by industry even have defined safety thresholds. This means that the possible public health risks from fracking sites could be even greater than these results suggest. 

Community-based Monitoring

The organizations were able to gather data from across the country by enlisting volunteers from local communities. Global Community Monitor, one of the project’s collaborators, trained teams of “Bucket Brigades” to collect field data. The name refers to the EPA-approved devices that use buckets to capture and seal air samples so that they can be analyzed off-site. Volunteers also used formaldehyde badges, which collect and measure levels of the chemical over an eight-hour period.

Using local volunteers has a number of benefits. Residents have local knowledge of where fracking practices are taking place. They can also choose where to measure based on symptoms that people are experiencing or by perceived odor and fumes (hydrogen sulfide, for instance, can be detected by its rotten egg smell). This allows locals to go out and test air samples when odors or symptoms increase – and thus capture intermittent releases.  

Finally, using local volunteers empowers communities to take ownership of the issue and provides them with evidence to back up the health symptoms they experience.

Moving Forward

The study helps fill in some of the gaps surrounding the public health effects of fracking, a poorly understood topic. Some states routinely test air quality but cannot keep pace with the rate of production in many shale fields. Texas, for instance, has one of the most extensive monitoring programs, but this consists of five permanent monitoring sites in a state where over 7,000 wells have been drilled since 2008.

The authors recommend increasing the monitoring of toxins near fracking sites and requiring public disclosure of chemicals used in fracking fluids. They see community monitoring as an excellent way to tap into local knowledge while extending state resources on air monitoring.

Finally, the regulations requiring that well pads be located a minimum distance from residences must be reevaluated. In the five states in this study with active wells, the average distance permitted between homes and fracking sites ranges between 150 and 500 feet. But the study identified formaldehyde up to 2,500 feet from fracking sites and benzene at more than 800 feet.

The study acknowledges that providing evidence of airborne toxins does not prove that fracking causes health problems. However, the findings do show that the air around fracking sites is often unhealthy and points to the need for greater attention to this vital public health issue.