For related articles and more information, please visit OCA’s Environment and Climate Resource Center page and our Health Issues page.


A Pennsylvania farmhouse sits below pipes and pumps used for hydraulic fracturing in 2011.

Oil and gas wells across the country are spewing “dangerous” cancer-causing chemicals into the air, according to a new study that further corroborates reports of health problems around hydraulic fracturing sites.

“This is a significant public health risk,” says Dr. David Carpenter, director of the Institute for Health and the Environment at the University at Albany-State University of New York and lead author of the study, which was published Thursday in the journal Environmental Health. “Cancer has a long latency, so you’re not seeing an elevation in cancer in these communities. But five, 10, 15 years from now, elevation in cancer is almost certain to happen.”

Eight poisonous chemicals were found near wells and fracking sites in Arkansas, Colorado, Pennsylvania, Ohio and Wyoming at levels that far exceeded recommended federal limits. Benzene, a carcinogen, was the most common, as was formaldehyde, which also has been linked to cancer. Hydrogen sulfide, which smells like rotten eggs and can affect the brain and upper-respiratory system, also was found.

“I was amazed,” Carpenter says. “Five orders of magnitude over federal limits for benzene at one site – that’s just incredible. You could practically just light a match and have an explosion with that concentration.

“It’s an indication of how leaky these systems are.”