Long-term exposure to contaminated drinking water may contribute to breast cancer risk through contact with carcinogens and endocrine-disrupting compounds that can accumulate in water supplies.[1][2] Since water is consumed daily over a lifetime, even low-level contamination can result in significant cumulative exposure.[3]
Research has identified several classes of water pollutants associated with cancer risk:
- PFAS (per- and polyfluoroalkyl substances): Known as “forever chemicals” because they persist in the environment and human body, PFAS have been linked to various health problems including cancer. Some studies suggest associations with breast cancer risk.[4][5]
- Arsenic: This naturally occurring element and industrial contaminant is a known human carcinogen that has been associated with breast cancer in some epidemiological studies.[6]
- Nitrates: Primarily from agricultural fertilizer runoff, high nitrate levels in drinking water have been linked to increased cancer risk through formation of carcinogenic N-nitroso compounds.[7]
- Industrial solvents: Trichloroethylene (TCE) and perchloroethylene (PCE), commonly used in dry cleaning and manufacturing, are probable carcinogens that can contaminate groundwater.[8][9]
- Disinfection byproducts: Trihalomethanes and haloacetic acids form when chlorine reacts with organic matter in water and have been associated with increased cancer risk in some studies.[10]
Where does water contamination come from?
Multiple sources contribute to drinking water pollution:
- Industrial discharge: Manufacturing facilities can release chemicals directly into waterways or through inadequate wastewater treatment[11]
- Agricultural runoff: Pesticides, herbicides, and fertilizers wash from farmland into surface and groundwater[12]
- Leaking underground storage tanks: Aging fuel tanks and chemical storage systems can leak contaminants into groundwater[13]
- Military installations and airports: PFAS-containing firefighting foam used at these sites has contaminated nearby water supplies[14]
- Aging infrastructure: Old pipes and treatment systems may leach contaminants or fail to adequately remove pollutants[15]
- Hazardous waste sites: Improperly disposed chemicals from Superfund and other contaminated sites can migrate into water supplies[16]
Who is most at risk?
Water contamination affects different communities unequally:
- Rural residents using private wells lack the regulatory oversight and treatment available for public water systems [17]
- Low-income communities and communities of color often have older, inadequately maintained water infrastructure [18]
- People living near industrial facilities, agricultural areas, or military bases face elevated exposure risks [19]
What can individuals do to protect themselves?
Consider implementing these water safety strategies:
- Test your water: Have your water tested by a certified laboratory, especially if using a private well or living in an area with known contamination
- Review water quality reports: Public water systems must provide annual Consumer Confidence Reports detailing contaminant levels
- Install appropriate filtration: Choose filtration systems certified to remove specific contaminants identified in your water (reverse osmosis for PFAS, activated carbon for chlorination byproducts, etc.)
- Maintain filters properly: Replace filters according to manufacturer recommendations to ensure effectiveness
- Use cold water for drinking and cooking: Hot water can leach more contaminants from pipes
- Flush pipes: Run water briefly before using if it has sat in pipes for several hours
- Stay informed: Sign up for alerts from your water utility about water quality issues
- Advocate for change: Support policies strengthening water quality standards, infrastructure investment, and source water protection
Bibliography
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[2] Hopenhayn-Rich, Claudia, Marsha L. Biggs, and Allan H. Smith. “Lung and kidney cancer mortality associated with arsenic in drinking water in Córdoba, Argentina.” International Journal of Epidemiology 27, no. 4 (1998): 561-569.
[3] Calderon, Rebecca L. “The epidemiology of chemical contaminants of drinking water.” Food and Chemical Toxicology 38, no. 1 (2000): S13-S20.
[4] Benbrahim-Tallaa, Lamia, Rodolfo Saracci, Neela Guha, Leon Siemiatycki, Kurt Straif, Yann Grosse, Dana Loomis, et al. “Carcinogenicity of perfluorooctanoic acid, tetrafluoroethylene, dichloromethane, 1,2-dichloropropane, and 1,3-propane sultone.” The Lancet Oncology 15, no. 9 (2014): 924-925.
[5] Vieira, Verónica M., Thomas F. Webster, Lauren M. Weinberg, Ann Aschengrau, and David M. Ozonoff. “Spatial analysis of lung, colorectal, and breast cancer on Cape Cod: an application of generalized additive models to case-control data.” Environmental Health 8, no. 1 (2009): 3.
[6] Smith, Allan H., Claudia Hopenhayn-Rich, Marsha N. Bates, Helen M. Goeden, Irva Hertz-Picciotto, Heather M. Duggan, Roger Wood, Michael J. Kosnett, and Marshall T. Smith. “Cancer risks from arsenic in drinking water.” Environmental Health Perspectives 97 (1992): 259-267.
[7] Ward, Mary H., Theo M. deKok, Paul Levallois, Jean Brender, Gwendolyn Gulis, Brian T. Nolan, and Jill VanDerslice. “Workgroup report: drinking-water nitrate and health—recent findings and research needs.” Environmental Health Perspectives 113, no. 11 (2005): 1607-1614.
[8] Aschengrau, Ann, David Ozonoff, Carole Paulu, Patricia Coogan, Robin Vezina, Timothy Heeren, and Yun Zhang. “Cancer risk and tetrachloroethylene-contaminated drinking water in Massachusetts.” Archives of Environmental Health 53, no. 3 (1998): 214-221.
[9] Chiu, Wan A., Ila Cote, Elaine A. Craft, Susan R. Glista-Baker, Daniel Krewski, Annie M. Jarabek, Judy S. LaKind, et al. “A framework for assessing the health risks associated with exposures to trichloroethylene.” Environmental Health Perspectives 121, no. 3 (2013): 303-316.
[10] Nieuwenhuijsen, Mark J., Josep Basagaña, Pilar Grellier, Diana Martinez, Silvia Cirach, Payam Dadvand, and Cristina M. Villanueva. “Air pollution, noise, blue space, and green space and premature mortality in Barcelona: a mega cohort.” International Journal of Environmental Research and Public Health 15, no. 11 (2018): 2405.
[11] Schwarzenbach, René P., Barbara I. Escher, Kathrin Fenner, Thomas B. Hofstetter, C. Annette Johnson, Urs von Gunten, and Bernhard Wehrli. “The challenge of micropollutants in aquatic systems.” Science 313, no. 5790 (2006): 1072-1077.
[12] Spalding, Roy F., and Mary E. Exner. “Occurrence of nitrate in groundwater—a review.” Journal of Environmental Quality 22, no. 3 (1993): 392-402.
[13] Moran, Michael J., James S. Zogorski, and Paul J. Squillace. “Chlorinated solvents in groundwater of the United States.” Environmental Science & Technology 41, no. 1 (2007): 74-81.
[14] Hu, Xindi C., Detlef R. U. Knappe, Amina Khor, Thomas Holm, and Christopher Higgins. “Per- and polyfluoroalkyl substances (PFASs) in drinking water systems and their removal.” In Contaminants of Emerging Concern in Water and Wastewater: Advanced Treatment Processes, edited by Helena Rivas Ibarra, 131-163. Valencia, Spain: AAHE, 2020.
[15] Pieper, Kelsey J., Rebekah Martin, Min Tang, LeeAnne Walters, Jeffrey Parks, Siddhartha Roy, Christina Devine, and Marc A. Edwards. “Evaluating water lead levels during the Flint water crisis.” Environmental Science & Technology 52, no. 15 (2018): 8124-8132.
[16] Agency for Toxic Substances and Disease Registry. Toxicological Profile for Trichloroethylene. Atlanta: U.S. Department of Health and Human Services, Public Health Service, 2019.
[17] Zheng, Yan, and Habibul Ahsan. “Contaminated drinking water and elevated blood arsenic as a risk factor for skin cancer: evidence from Chakdaha, West Bengal, India.” Cancer Epidemiology, Biomarkers & Prevention 21, no. 12 (2012): 2074-2075.
[18] Switzer, David, and Manuel P. Teodoro. “The color of drinking water: class, race, ethnicity, and safe drinking water act compliance.” Journal‐American Water Works Association 110, no. 9 (2018): E24-E39.
[19] Hu, Howard. “Exposure to metals.” Primary Care 27, no. 4 (2000): 983-996.
