Modern hydraulic fracturing ("fracking") is so new that over half of all the shale gas ever developed in the world has been produced in the last three years, which has resulted in nearly all of the peer-reviewed scientific research on the environmental and public health consequences of shale gas having been done in the last 14 months.

The resulting "research gap" is troubling since there are so many emerging signs of major health and environmental harms from fracking, according to Cornell Professor Robert W. Howarth, Ph.D., who testified today before the Subcommittee on Technology, Information Policy, Intergovernmental Relations and Procurement Reform of the U.S. House Committee on Oversight and Government Reform.

In issuing an urgent call for more research and also advising caution about uncritically relying upon shale gas as a "bridge fuel," Professor Howarth highlighted the following concerns: -- Groundwater contamination: There are several reports of contamination of drinking water wells and surface aquifers by fracking fluids, particularly in Pennsylvania and in Colorado. A recently published model suggests there may also be a threat of migration of contaminated fracking fluids from depth to surface drinking water aquifers over time through fissures and cracks. The U.S. EPA is currently pursuing a comprehensive study of groundwater contamination from hydraulic fracturing, and intends to release a preliminary report later this year and a final report in 2014. Shale gas development also leads to contamination of drinking water wells, as indicated by a May 2011 study published by Duke University scientists in the Proceedings of the National Academy of Sciences. Methane concentrations were frequently elevated in drinking water wells within 1 kilometer of shale gas operations, sometimes at levels great enough to pose a significant risk of explosion.

-- Local air pollution: The development of shale gas and other unconventional forms of natural gas (from coal-bed seams and tight-sand formations) results in significant local air pollution. One concern is the release of benzene and other aromatic hydrocarbons to the atmosphere from routine operations. State officials in Texas have reported benzene concentrations in the air near gas operations that sometimes exceed acute toxicity standards. In Pennsylvania, reported benzene concentrations are so far lower, quite likely because the rate of gas development has been much lower. Nonetheless, reported atmospheric benzene levels near some drilling operations in Pennsylvania are high enough to pose risk of cancer from chronic exposure.

-- Ozone pollution: Ozone is created in the atmosphere when nitrogen pollution and organic compounds react under strong sunlight. Current ozone pollution in the U.S. is estimated to cause 30,000 premature deaths each year, almost the same death rate as from automobile accidents. Unconventional natural gas development from hydraulic fracturing increases ozone pollution due to leakage of organic compounds to the air. The problem has been particularly acute in Wyoming, Utah, and Colorado in recent years, with ozone concentrations in the winter due to natural gas development being higher than observed in New York City.

-- Surface water pollution: Shale gas development has already caused significant surface water pollution. The additives used in hydraulic fracturing include toxic and carcinogenic substances, such as formaldehyde, benzene, xylene, and monoethanolamine. As importantly, frac fluids extract chemical substances from shales, including toxic and carcinogenic aromatic hydrocarbons, toxic metals, and radioactive materials such as uranium, thorium, and radium. Some of these materials are released to the environment when blowouts and other accidents occur. A greater route of release and exposure comes from disposal of frac-return fluids. Approximately 20 percent, or 1 million gallons or so, of the material used in hydraulic fracturing flows back to the surface in the first few weeks after fracturing, with all of the added and extracted chemical substances. Public drinking water supplies in the Pittsburgh area have already been affected, with elevated bromides from the waste interacting with chlorination in public drinking water systems to produce highly dangerous brominated organic compounds.

-- Methane and global warming: Methane is released to the atmosphere during development, transport, storage, and use of natural gas.

Methane is an incredibly powerful greenhouse gas, and as a result of methane emissions, both shale gas and conventional natural gas have larger greenhouse gas footprints than other fossil fuels such as oil and coal (when viewed over an integrated 20-year time frame after emission). Recent climate models point to the urgency in reducing methane emissions. Currently, almost 40 percent of all atmospheric methane released by human activity in the U.S. comes from the natural gas industry. Most studies indicate that shale gas development releases 40-60 percent more methane than does conventional natural gas.

-- Radon in natural gas supplies: Radon gas is a carcinogen, and exposure to radon is the largest source of public exposure to ionizing radiation in the U.S. Natural gas contains radon, and using natural gas for home cooking is one route of home exposure. Shale gas from the Marcellus formation has much greater levels of radon than does conventional natural gas. This is because the Marcellus shale is particularly rich in uranium and thorium, and radon is formed from the decay of these radioactive materials. Radon has a half life of 3.8 days, so with sufficiently long storage, the radon decays away and poses less public health risk.

For the full text of Professor Howarth's testimony, go to

Robert Howarth is a biogeochemist and ecosystem biologist.  He is a tenured faculty member at Cornell University, where he has held an endowed faculty position, the "David R. Atkinson Professor of Ecology & Environmental Biology," since 1993.  Howarth is the founding editor of the journal Biogeochemistry and an adjunct senior research scientist at the Marine Biological Laboratory in Woods Hole, MA.   He has conducted research and published scientific papers on environmental risk assessment and the consequences of pollution, including the effects of oil and gas development, since the mid 1970s.

In 2011, Howarth published the first comprehensive peer-reviewed analysis of the greenhouse gas footprint of shale gas in the journal Climatic Change Letters and an invited commentary on shale gas in Nature. For this, he was named by Time magazine as "one of the people who matter" for 2011. In the first few months of 2012, Howarth published a follow-up paper on this research in Climatic Change and was the lead author of a background paper for the National Climate Assessment on the role of methane from the natural gas industry on global change.  Howarth has published over 200 scientific papers, reports, and book chapters.

Howarth is a member of the Board of Directors of Physicians, Scientists, and Engineers for Healthy Energy (PSE).

ABOUT PSE The nonprofit Physicians Scientists & Engineers for Healthy Energy (PSE) is dedicated to supplying vetted, evidence-based, scientific information and resources on unconventional gas development (high-volume hydrofracking) and other novel energy production methods.

PSE's mission is to bring transparency to the important public policy issues surrounding such methods, helping to level the playing field for citizens, advocacy groups, media, policy-makers and politicians.

For more information, go to on the Web.

SOURCE Physicians, Scientists & Engineers for Healthy Energy, Washington DC -0- 05/31/2012 /Web Site: CO: Physicians, Scientists & Engineers for Healthy Energy, Washington DC ST: District of Columbia IN: GAS OIL ENV HEA UTI SU: AVO ENI ENP SVY NPT PRN -- DC16725 -- 0000 05/31/2012 16:23:06 EDT http://www.prnewswire.c