Hydraulic Fracturing

Hydraulic fracturing is a process of fracturing rock with the help of mixed fluid pressurization to obtain gas from the shale. Shallow wells have limitations of gas production due to low permeability of sedimentary rock containing gas. Hydraulic fracturing facilitates the fluids to flow in the rock and production of gas from the shale (Arthur and Coughlin, 2008).

Water based fluids are the most common fracturing fluid however foam based, oil based, acid based, alcohol based and emulsion based fluids can be used in hydraulic fracturing (Gandossi, 2013). Enormous amount of freshwater is needed in fracturing process and the waste water has to be treated before releasing into the environment. Fracturing processing may increase the risk of drinking water contamination of the adjacent areas. Environmental risks such as methane pollution, air pollution impacts, blowouts due to gas explosion, fracking-induced earthquakes may be associated with hydraulic fracking and production of gas (Hoffman, J., 2012).

Toxic chemicals used during the fracturing process and release of toxic and radioactive chemicals are detrimental to the environment (networkforphl.org, n.d.). Chemicals such as hydrochloric acid, ammonium chloride, ammonium persulfate, isopropanol, formic acid, potassium metaborate, triethanol -amine zirconate, methanol, citric acid, lauryl sulfate, naphthalene are used in the mixed fracturing fluid (fracfocus.org, 2015). Chemicals used in the fracturing process acts as clay stabilizer, breaker, biocide, cross- linker, friction reducer, gelling agent, iron control, pH adjusting agent, scale inhibitor and surfactant (fracfocus.org, 2015). Shales containing organic acids, volatile organic compounds, trace elements such as mercury, lead and arsenic and radioactive elements such as radium, thorium and uranium can be released into the environment (networkforphl.org, n.d.).


Arthur, J.D. and Coughlin, B.J. (2008) Evaluating the Environmental Implications of Hydraulic Fracturing in Shale Gas Reservoirs [Online] Available at http://www.all-llc.com [Accessed on 23 February 2015].

FracFocus (2015) What Chemicals are Used [Online] Available at http://www.fracfocus.org [Accessed on 23 February 2015].

Gandossi, L. (2013) An Overview of Hydraulic Fracturing and other Formation Stimulation Technologies for Shale Gas Production [Online] Available at http://www.ec.europa.eu [Accessed on 23 February 2015].

Hoffman, J. (2012) Potential Health and Environmental Effects of Hydro fracturing in the Williston Basin, Montana [Online] Available at http://www.carleton.edu [Accessed on 23 February 2015].

Network for Public Health Law (n.d.) Environmental Impacts Associated with Hydraulic Fracturing Available at http://www.networkforphl.org [Accessed on 23 February 2015].


Health Effects of Cadmium

Presence of cadmium in drinking water is hazardous to human health. Renal, cardiovascular, respiratory and skeletal effects have been found to be induced by cadmium exposure. Cadmium can induce renal tubular dysfunction leading to renal lesion and irreversible impairment of reabsorption capacity of renal tubules. Combine concentration of metallothionein, a cadmium binding protein, and cadmium can be found in the renal cortex of Kidneys (Queensland Health, 2002). Increased excretion of low molecular weight proteins such as B2-microglobulin and alpha1-microglobulin and enzymes such as N-acetyl-B-D-glocosaminidase (NAG) or tubular proteinuria may be caused by exposure to cadmium (Jarup, 2003; WHO, 2011). Destroyed arrangement of mineral metabolism and nutritional deficiencies are associated with accumulation of cadmium in the Kidneys (Queensland Health, 2002).

Kidney stones have been associated with cadmium. Renal damage and conditions such as hypercalciuria and hyperphosphateuria may result kidney stone (CDC, 2013). Skeletal damage, osteomalacia or osteoporosis might occur as a result of long term exposure to Cadmium (Jarup, 2003; WHO, 2011). Many cases of skeletal disease also known as itai-itai disease was reported in Japan in the 1950s due to long term exposure to cadmium in drinking water (Jarup, 2003; WHO, 2011).

Respiratory disease and bone disease could be resulted due to long term (20-30 years) accumulation of cadmium in Kidney (ICdA, n.d.). Stomach irritation, vomiting and diarrhoea could be resulted from drinking water with high levels of cadmium (Illinois Department of Public Health, n.d.; Queensland Health, 2002). Illinois Department of Public Health (n.d.) suggested the probability of low birth weight babies for women exposed to cadmium. Suppression of testicular function could be induced by Cadmium toxicity (Queensland Health, 2002).


Centres for Disease Control and Prevention (CDC) (2013) Cadmium Toxicity: What Diseases are Associated with Chronic Exposure to Cadmium [Online] Available at www.cdc.gov [Accessed on 09 January 2015].

Illinois Department of Public Health (n.d.) Environmental Health Fact Sheet [Online] Available at www.idph.state.il.us [Accessed on 5 January 2015].

International Cadmium Association (ICdA)(n.d.) Cadmium Exposure and Human Health [Online] Available at www.cadmium.org [Accesses on 5 January 2015].

Queensland Health (2002) Cadmium [Online] Available at www.health.gld.gov.au [Accessed on 5 January 2015].

World Health Organization (WHO) (2011) Cadmium in Drinking Water: Background Document for Development of WHO Guidelines for Drinking Water Quality [Online] Available at www.who.int [Accessed on 5 January 2015].