The oil and gas drilling industry has been reluctant to disclose all the contents of the hydraulic fracturing fluid, saying some information is a trade secret that would give competitors an advantage.
"By and large, that argument is specious," said energy expert Kent Moors, a Duquesne University professor and scholar in residence at Duquesne's Institute for Energy and the Environment. Revealing the additives and chemicals in the fluid does not reveal the formula used to make the fracking fluid, he said.
The industry says hydraulic fracturing is a proven technique used for more than 50 years. The fluid used is pumped thousands of feet below water supplies. About 98 percent of the fluid is water and sand used to prop open fissures. The remaining 2 percent, with various additives to spur production, is the focus of attention and controversy.
The American Petroleum Institute favors full disclosure of the fracking fluid, said Erik Molito, the trade group's upstream director.
Some components are common household items and are generally harmless, such as salt and citric acid. Others are extremely toxic, such as benzene and lead, according to a House of Representatives Energy Committee report issued in April. From 2005 to 2009, the oil and gas service companies used 780 million gallons of fracturing fluid containing 29 products, some of which were potentially cancer- causing, are regulated as a risk to human health or listed as a hazardous air pollutant, the House report said.
Pennsylvania, Arkansas and Wyoming have regulations requiring companies to disclose the additives and the chemicals used in each well, and permit drillers to designate some chemicals as trade secrets that should not be disclosed.
When a company lists an additive or chemical component as a "trade secret," Arkansas and Wyoming conduct an initial review to determine whether it agrees with that assessment.