The abrupt rise in shale gas exploration around the globe is due to the increase demand of gas energy , prompting concerns about the impact of the technology.

The danger pose in contaminating nearby source of drinking water with methane through shale gas drilling operations is high, the study suggested.

High concentrations of methane that reaches up to 17 times above normal are noted by researchers where samples were taken near the drilling sites.

“We found surprising levels of methane in home-owners’ wells that were close to natural gas wells, ” co-author Rob Jackson, Nicholas Professor of Global Change at Duke University, North Carolina, explained.

The research team from Duke University, has collected samples from 68 private water wells in the north-eastern states of Pennsylvania and New York.

The findings appear in the Proceedings of the National Academy of Sciences.