Alex Wayne, 2012 Bloomberg News


 (Updates with lawmaker comment in fifth paragraph.)

Jan. 9 (Bloomberg) -- 

 The U.S. should declare a moratorium on hydraulic
fracturing for natural gas in populated areas until the health effects are
better understood, doctors said at a conference on the drilling process.

Gas producers should set up a foundation to finance studies on fracking
and independent research is also needed, said Jerome Paulson, a
pediatrician at George Washington University School of Medicine in
Washington.

 Top independent producers include Chesapeake Energy Corp. and
Devon Energy Corp., both of Oklahoma City, and Encana Corp. of Calgary,
according to Bloomberg Industries.

 "We've got to push the pause button,
and maybe we've got to push the stop button" on fracking, said Adam Law,
an endocrinologist at Weill Cornell Medical College in New York, in an
interview at a conference in Arlington, Virginia that's the first to
examine criteria for studying the process.

 Fracking injects water, sand
and chemicals into deep shale formations to free trapped natural gas. A
boom in production with the method helped increase supplies, cutting
prices 32 percent last year.

 The industry, though, hasn't disclosed enough
information on chemicals used, Paulson said, raising concerns about
tainted drinking water supplies and a call for peer- reviewed studies on
the effects. The EPA is weighing nationwide regulation.

Longstanding Process 

"We need to understand fully all of the chemicals that are shot into the 
ground, that could impact the water that children drink," Representative
Ed Markey of Massachusetts, a senior Democrat on the House Energy and
Commerce Committee, said in a phone interview. The industry is trying "to
block that information from being public," he said.

 The gas industry has
used hydraulic fracturing for 65 years in 30 states with a "demonstrable
history of safe operations," said Chris Tucker, a spokesman for Energy In
Depth, a Washington-based research and advocacy group financed by oil and
gas interests, in an e-mail.

 Drilling in shale deposits in the eastern
U.S. began in 2004. Gas drillers have to report to the U.S., state and
local authorities any chemicals used in fracking that are "considered
hazardous in high concentrations" in case of spills or other emergencies,
Tucker said.

 Those reports don't include amounts or concentrations, he
said.

 The industry created a public website last April for companies to
voluntarily report lists of chemicals used in individual wells, including
concentrations.

 Colorado and Wyoming have passed laws requiring drillers
to file reports to the website, Tucker said.

Hazards Unknown 

Despite those disclosures, U.S. officials say they don't know all of the 
hazards associated with fracking chemicals.

 "We don't know the chemicals
that are involved, really; we sort of generally know," Vikas Kapil, chief
medical officer at National Center for Environmental Health, part of the
U.S. Centers for Disease Control and Prevention, said at the conference.

"We don't have a great handle on the toxicology of fracking chemicals."

The government has found anecdotal evidence that drilling can contaminate
water supplies.

 In December, the EPA reported that underground aquifers
and drinking wells in Pavillion, Wyoming, contained compounds that
probably came from gas drilling, including glycols, alcohols, benzene and
methane.

 The CDC has detected "explosive levels of methane" in two wells
near gas sites in Medina, Ohio, Kapil said.  He said he wasn't authorized
to take reporters' questions after his presentation.

Chemicals Used 

Fluids used in hydraulic fracturing contain "potentially hazardous 
chemical classes," Kapil's boss, Christopher Portier, director of The
National Center for Environmental Health, said last week.

 The compounds
include petroleum distillates, volatile organic compounds and glycol
ethers, he said.

 Wastewater from the wells can contain salts and
radiation, Portier said. U.S. natural gas production rose to a record 2.5
trillion cubic feet in October, a 15 percent increase from October 2008.

 A moratorium on fracking pending more health research "would be reasonable,"
said Paulson, who heads the Mid- Atlantic Center for Children's Health and
the Environment in Washington, in an interview. 

His group is funded in
part by the CDC and Environmental Protection Agency, he said, and helped
sponsor the conference with Law's organization, Physicians Scientists and
Engineers for Healthy Energy.

 Tucker called the CDC's participation in the
conference "disappointing," saying the conference is "a closed-door pep-
rally against oil and natural gas development."

 Representatives of Chevron
Corp., Exxon Mobil Corp. and the American Petroleum Institute, a trade
group, registered to attend the conference.