See report, U.S. Congress, minority report, list of fracking chemicals.
From Executive Summary:
… Hydraulic fracturing has helped to expand natural gas production in the United States, unlocking large natural gas supplies in shale and other unconventional formations across the country. As a result of hydraulic fracturing and advances in horizontal drilling technology, natural gas production in 2010 reached the highest level in decades. According to new estimates by the Energy Information Administration (EIA), the United States possesses natural gas resources sufficient to supply the United States for approximately 110 years.
As the use of hydraulic fracturing has grown, so have concerns about its environmental and public health impacts. One concern is that hydraulic fracturing fluids used to fracture rock formations contain numerous chemicals that could harm human health and the environment, especially if they enter drinking water supplies. The opposition of many oil and gas companies to public disclosure of the chemicals they use has compounded this concern…
PAGE 8: The oil and gas service companies used hydraulic fracturing products containing 29 chemicals that are (1) known or possible human carcinogens, (2) regulated under the Safe Drinking Water Act for their risks to human health, or (3) listed as hazardous air pollutants under the Clean Air Act. These 29 chemicals were components of 652 different products used in hydraulic fracturing. Table 3 lists these toxic chemicals and their frequency of use. Hydrogen fluoride (Hydrofluoric acid) is listed in Table 3.
PAGE 11: … Hydrogen fluoride is a hazardous air pollutant that is a highly corrosive and systemic poison that causes severe and sometimes delayed health effects due to deep tissue penetration. Absorption of substantial amounts of hydrogen fluoride by any route may be fatal [reference 1 below]. One of the hydraulic fracturing companies used 67,222 gallons of two products containing hydrogen fluoride in 2008 and 2009.
PAGE 13-30: Appendix A. Chemical Components of Hydraulic Fracturing Products, 2005-2009 include:
Ammonium bifluoride (Ammonium hydrogen difluoride), CAS # 1341-49-7. There are 10 fracking products that contain this.
Ammonium fluoride, CAS # 12125-01-8. There are 9 fracking products that contain this.
Calcium fluroide, CAS # 7789-75-5. There are 2 fracking products that contain this.
Fluoroaliphatic polymeric esters, no CAS #. There is 1 fracking product that contains this.
Hydrogen fluoride (Hydrofluoric acid), CAS # 7664-39-3. There are 2 fracking products that contain this.
1. U.S. Department of Health and Human Services, Agency for Toxic Substances and Disease Registry, Medical Management Guidelines for Hydrogen Fluoride.