FORT COLLINS - More studies are needed to determine how large a role the oil and gas industry plays in increased ozone levels, according to panelists at the Natural Gas Symposium.

The two-day conference, which started Tuesday, focuses on natural-gas development and how it affects the economy, energy use, climate, environment and health. The symposium is sponsored by Colorado State University.

The panel of representatives from Noble Energy Inc. (NYSE: NBL), Colorado State University and Western Resource Advocates discussed effects of oil and gas development on air and water Tuesday at the two-day conference on natural gas at the Fort Collins Hilton.

Oil and gas production emits volatile organic compounds, which contribute to ozone, or smog formation, according to the Environmental Protection Agency.

Gary Graham of the Boulder-based environmental group Western Resource Advocates said studies indicate that oil and gas development causes pollution. Increased regulations could be modified as scientists learn more about oil and gas' role in air pollution.

"We have to take the science that we have now and develop regulations. Err on the side of protection," he said.

Scientists have measured higher ozone levels in areas with heavy oil and gas development in Wyoming and Utah, said Jeff Collett a professor in CSU's Atmospheric Science department.

Bob Bemis, vice president of Environmental, Health and Safety for Noble Energy, said studies are mixed on oil and gas development's affect on air quality. More data is needed to fully evaluate the matter.

Earlier at the symposium, chief executives of major energy companies told the audience that regulation can help drive innovation amid a shale oil and gas boom that has led to an abundant U.S. supply of those fossil fuels.

Good regulation stimulates innovation, said Chuck Davidson, CEO of Noble Energy Inc. (NYSE: NBL). Regulation also can give the public confidence in oil and gas development.

"To me, regulation is one of the components that can help," Davidson said.

Davidson made the remarks during an executive roundtable Tuesday. Hilton Fort Collins on Tuesday.

"We've got to get our emissions down," Davidson said. "In the end, it's got to be close to zero."

Jeffrey Immelt, CEO of General Electric Co. (NYSE: GE), said that people must join to help create good regulations instead of simply saying no to natural-gas development.

"This is the era of solving problems," Immelt said.