People who live in areas near hydraulic fracturing are more likely to be hospitalized for heart conditions, neurological illnesses and cancer, according to researchers from the University of Pennsylvania and Columbia University.

Fracking is an oil and gas extraction technique using a mixture of water, chemicals and sand to break apart underground rock formations. It has triggered a surge in U.S. energy production in recent years, along with a debate over whether the process causes air and water pollution.

The study, published this week in the journal PLOS ONE, looked at hospitalization rates in parts of Pennsylvania from 2007 to 2011 and found them significantly higher in areas with fracking compared to those without.

"At this point, we suspect that residents are exposed to many toxicants, noise and social stressors due to hydraulic fracturing near their homes and this may add to the increased number of hospitalizations," Reynold Panettieri, one of the study's authors, said in a press release.

The team found that 18 ZIP codes in its study had a well density greater than 0.79 wells per square kilometer, and residents living in these ZIP codes were predicted to have a 27 percent increase in hospitalizations for heart conditions compared to areas without any drilling. The study also showed higher rates of hospitalization for neurological illness, skin conditions and cancer.

The researchers said the study does not prove any cause and effect between drilling and health problems but that the findings "suggests that healthcare costs of hydraulic fracturing must be factored into the economic benefits of unconventional gas and oil drilling."

The energy industry and proponents of fracking say the technology can be used safely and that fears of pollution and health risks are overblown.