Hydraulic fracturing - fracking - is in the headlines a lot these days, and like all issues where science and policy mix, political opinion often outweighs facts.  Natural gas due to fracking has driven CO2 emissions from US energy back to early 1990s levels and emissions from coal back to early 1980s levels, while keeping heat affordable for America's poor.

Yet despite its benefits, the EPA and environmental activists have been looking for reasons to ban it, along with most conventional fuel. It's been the case that wells with methane or an earthquake is blamed on fracking, even if the methane was natural or the earthquake turned out to be from conventional drilling. The public relations efforts by the government have been so aggressive a Federal court had to order the EPA to stop blaming fracking if they hadn't done an investigation.

To separate fact from fiction about the oil and gas extraction technique and its health effects,   the meeting of The Geological Society of America (GSA) in Denver yesterday had a multidisciplinary session on fracking and health. Unfortunately, the people most concerned are not experts in geology and don't attend science meetings.

"There is so much perceived information on fracking in the media, with so little of it based on real science and actual data," says Thomas Darrah, a medical geologist at Ohio State University and one of the conveners of the GSA Pardee Keynote Session, "Energy and Health: The Emergence of Medical Geology in Response to the Shale Gas Boom."

"Fracking has moved so quickly, and the research community is playing catch up on water, air, and health issues," said Robert Jackson, an environmental scientist at Duke University who will present his research this Sunday. "The goal is to present a state of the science for researchers and the public."

The afternoon keynote session is designed to cover a lot of ground. It will start with the geologists, hydrologists, and air-quality experts who are studying the chemistry and the physical properties of fracking in the ground, water, and air. Then the session veers into territory not often covered at a geological meeting, with talks by toxicologists, researchers in occupational medicine, and epidemiologists.

"This session includes people who would normally not be anywhere near a GSA conference," said Darrah. "The idea is that we end the session by having the geoscience community interact with a group of people who are looking at health data sets: epidemiologists. That way we can put people working on the other end of the equation in the same room." Included in the eleven scheduled presentations, and at the medical end of the equation, is a talk titled "Public Health Implications of Hydraulic Fracturing," by David O. Carpenter of the University of Albany's School of Public Health, and another, "Energy and Health: The Emergence of Medical Geology in Response to the Shale Gas Boom: An Occupational and Environmental Medicine Perspective," to be delivered by Theodore F. Them of Guthrie Clinic Ltd.

For his part, Darrah will be presenting a talk about his work, "Understanding In-House Exposures to Natural Gas and Metal-Rich Aerosols from Groundwater within an Unconventional Energy Basin."

There are two additional presentations on the air-quality issues of fracking, which is perhaps the topic the public knows the least about. Gabrielle Petron of the University of Colorado and NOAA will be talking about outdoor air emissions from hydraulic fracturing activities, and public health researcher Lisa M. Mackenzie of the University of Colorado will talk about work evaluating specific health risks from exposure to natural gas drilling in Garfield County, Colorado.