May 21, 2014

What’s “fracking” anyway?

Hydraulic fracturing or “fracking” is a well stimulation process used in oil and gas production that involves blasting huge amounts of water mixed with sand and dozens of chemical components deep into the earth, breaking up underground rock formations to facilitate oil and gas extraction.  In California, fracking is mostly used to drill for oil. Whether fracking for oil or gas, the method and related processes pose serious consequences for our health and the health of the environment.  It is cause for great concern for San Francisco Bay Area PSR and here’s why.

Is there fracking in California?

In California, the oil and gas industry have been fracking for almost 60 years[i]; however, in order to expand access to underground sources, relatively newer processes are being utilized such as directional (non-vertical, slanted or horizontal) and new chemical solutions. Oil and gas producers now have the capacity to drill over a mile into the earth.

Fracking has been documented in 10 California counties—Colusa, Glenn, Kern, Los Angeles, Monterey, Sacramento, Santa Barbara, Sutter, Kings and Ventura.[ii]  In Kern County, California’s major oil-producing county, 50-60% of new oil wells use fracking.[iii]  Oil companies are also fracking offshore.[iv]  In 2009, California produced 229.8 million barrels of oil. [v]  Drilling for oil and gas is on the rise in this state.[vi]   The largest shale oil reserve in the country is in the Monterey Shale in California and contains an estimated 13.7 billion barrels of recoverable oil.[vii] 

What are the health and other impacts of fracking?

Because disclosure has not been required until very recently with the passage of state Senate Bill 4 (Pavley) in 2013, it is unknown for certain which chemicals the oil and gas industry are using in California. But New York State knows that nearly 200 chemicals are being used or proposed for use in fracking operations there. Among them are 10 chemicals known under California’s Proposition 65 program to cause cancer and/or reproductive harm.[viii] Health impacts of many of the chemicals include adverse effects on the nervous system, liver, kidneys, blood-cell-forming tissues, respiratory and gastrointestinal tracts, as well as general irritation to the skin, eyes, nose, and throat.[ix]  For many chemicals on New York’s list, there is little information at all on their potential health hazards.

There is evidence that chemicals used in fracking or released during the process are contaminating underground water supplies.[x]  Even though chemicals often constitute less than 0.5% of fracking fluid, tens of thousands to millions of gallons of fluid are used in a fracking blast.[xi]   For some chemicals, even a little can be harmful. A single teaspoon of benzene is enough to contaminate more than 260,000 gallons of water to a level that exceeds EPA’s drinking standard of 5 parts per billion.[xii] According to the EPA, there is no safe level of benzene to protect against its potential harm.[xiii]

The use of diesel fuel for fracking is also troubling.  Diesel fuel contains benzene as well as toluene, ethylbenzene and xylene (BTEX), chemicals which are toxic at low concentrations.   These chemicals pose a range of health risks including cancer, developmental and reproductive harm, liver and kidney damage and nervous system disorders.[xiv] In 2011, a Congressional investigation found that 26,444 gallons of diesel fuel had been injected into California wells in fracking fluids from 2005-2009.[xv] 

Water quality can also be compromised by methane contamination during drilling and the fracturing of rock formations. Lead, arsenic and radioactive materials are brought to the earth’s surface with waste water from fracking.  Methods to store these waters are inadequate to prevent leaks or evaporation into the air.[xvi] 

Fracking can release many of the same dangerous chemicals into the air, contributing to air pollution and, consequently, to a potential increased incidence of cancer. Releases can increase levels of ground-level ozone, a key risk factor for respiratory illness.  Significant emissions of methane, which is 30 times more potent as a greenhouse gas contributing to climate change than carbon dioxide, have been associated with natural gas operations including fracking.[xvii]   Climate change brings with it a number of anticipated health effects including “heat waves, extreme weather events, flooding, water contamination, sea level rise, expansion of insect ranges and populations, worsening air quality, crop damage, and social instability and conflict.”[xviii]

Prevent Harm Before it Happens

There is still a lot that is unknown about fracking and its impacts on health and the environment, and what is known is not good.  That’s why State Senators Holly Mitchell and Mark Leno are trying to put the brakes on fracking in California by authoring Senate Bill 1132 which calls for a moratorium on well stimulation processes like fracking.  The bill would prohibit all well stimulation in the state until a comprehensive study on the environmental and health effects of the processes is completed, and there is assurance that the processes do not pose a risk to human health and the environment.  In keeping with appropriate application of the Precautionary Principle, we think this is the proper primary prevention approach in the face of persistent uncertainty as to the safety of fracking, SF Bay Area PSR supports this important piece of legislation; we hope you will too.

[i] Environmental Working Group, Renee Sharp and Bill Allyaud, California Regulations: See No Fracking, Speak No Fracking (EWG Report),, p. 14.

[ii]Center for Biological Diversity, Fracking in California: Questions and CONCERNS),, accessed March 31, 2014.

[iii] Ibid.

[iv] Ibid.

[v] EWG Report, p. 18.

[vi] Ibid.

[vii] Clean Water Action, Fracking in California,, accessed March 31, 2014.

[viii] EWG Report, p. 16; California Office of Environmental Health Hazard Assessment. 2012. Proposition 65 list of chemicals known to the state to cause cancer or reproductive toxicity (Prop 65 list).

[ix] EWG Report, p. 17.

[x] Physicians for Social Responsibility, Jake Hays and Adam Law, MD, Public Health Concerns of Shale Gas Development (PSR Brief), (accessed March 31, 2014)

[xi] EWG Report, p. 16.

[xii] Ibid.

[xiii] U.S. Environmental Protection Agency Consumer Factsheet:, (accessed March 31, 2014)

[xiv] EWG Report, p. 17; U.S. Environmental Protection Agency Consumer Factsheets: (accessed March 31, 2014)

[xv] EWG Report, p. 17.

[xvi] PSR Brief.

[xvii] Davenport C. Study finds methane leaks negate benefits of natural gas as a fuel for vehicles. New York Times. February 13, 2014. Available at: April 4, 2014.

[xviii] Ibid.