The safest source water is a protected groundwater aquifer with a confining geological layer. When used as the source of the bottled water a protected groundwater aquifer could go a long way to ensuring the water quality, consistency of taste and the absence of cryptosporidium, a microscopic parasite that lives in the intestine of infected animals and humans and occurs mainly in surface water sources, such as lakes, streams and rivers. The safest bottled water like the safest source of any drinking water is from a protected groundwater aquifer or spring, though groundwater aquifers are potentially vulnerable to a wide range of man-made and naturally occurring contaminants, including many that are not regulated in drinking water under the SDWA, or by the FDA for bottled water.

Back in 2007 the Environmental Working Group (EWG) had laboratory analysis performed on bottled water and found that 10 popular brands purchased from grocery stores and other retailers in 9 states and the District of Columbia, contained in total 38 chemical pollutants, with an average of 8 contaminants in each brand. The analyses was conducted by the University of Iowa Hygienic Laboratory and found a wide range of pollutants, including not only disinfection byproducts, but also common urban wastewater pollutants like caffeine and pharmaceuticals (Tylenol); heavy metals and minerals including arsenic and radioactive isotopes; fertilizer residue (nitrate and ammonia); and a broad range of other, tentatively identified industrial chemicals used as solvents, plasticizers, viscosity decreasing agents, and propellants. These are all contaminants that are more characteristic of large system tap water that includes surface water in their water mix rather than a protected groundwater source. In fact, it appeared likely in at least two instances that the water was tap water.

More than one-third of the chemicals identified by the EWG were substances that are not regulated in bottled water by the FDA. Whether a particular contaminant in water is potentially harmful to human health depends on the contaminant’s toxicity and concentration in drinking water. Other factors include the susceptibility of individuals, amount of water consumed, and duration of exposure. Some of the chemicals found are regulated in California in drinking water and exceeded the maximum contaminant level (MCL) under California’s Safe Drinking Water and Toxic Enforcement Act of 1986 (Proposition 65). California has one of the most extensive and stringent lists of chemicals with MCLs for drinking water and their list is used as a standard for human exposure of substances not regulated under the FDA or SDWA, but many substance found in the bottled water samples are not regulated in water at all. Some of the bottled water tested by the EWG was found to be contaminated with bacteria. EWG’s report did change the regulatory awareness of the problem, increase public awareness of the problem and ultimately nudged some in the bottled water industry to disclose the source of their water or some indication of the source of the water.

The EWG report was followed by a Governmental Accountability Office (GAO) report criticizing the FDA and by Congressional Hearings. There seems to have been little progress the 2009-2010 EWG survey of 173 unique bottled water products found some improvements in product identification and labeling. Despite California’s bottled water law, SB 220, intended to provide transparency as to source and treatment for bottled water there seemed to be little improvement. The EWG found many popular brands of bottle water stated on their labels that water testing results were available from web sites or customer service numbers only to find that the results were, in fact, not available. The purity of bottled water remains in question yet many continue to buy bottled water. There are two independent certifications that often appear on bottled water. The International Bottled Water Association (IBWA) is a trade organization for water bottlers. IBWA members must meet the organization’s “model code” and are subject to annual inspections by an independent third party. Bottlers belonging to IBWA frequently indicate membership on their labels. NSF International - Bottled water certified by NSF undergoes additional testing by unannounced annual plant inspections. NSF certifications mean that the bottler complies with all applicable FDA requirements, including good manufacturing practices.

People may prefer bottled water because of its taste or simply as a healthier drink choice. The taste of all water has to do with the way it is treated and the quality of its source water, including its natural mineral content. According to the EPA, most bottled water comes from groundwater, where water quality varies less from day to day. The water is treated and immediately bottled. Bottled water from a dedicated source may have a more consistent taste than tap water, which in the large population centers is mixed and predominately comes from surface sources and must travel through pipes to reach homes. One of the key taste differences between tap water and bottled water is due to how the water is disinfected. Tap water may be disinfected with chlorine, chloramine, ozone, or ultraviolet light to kill disease-causing germs. Water systems use these disinfectants chlorine and chloramine because they are effective and inexpensive, and they continue to disinfect as water travels through the system pipes and pumps. There is often a residual taste. There are many groundwater sources that do not need to be disinfected and when necessary or desirable the bottled water industry typically uses ozone or ultraviolet light to disinfect the water. These methods leave no residual taste.

EWG and Good Housekeeping recommend that consumers drink filtered tap water or well water that has also been tested and filtered. Though there are no home filters that are certified to remove pharmaceuticals and certain other (emerging) contaminants, Good Housekeeping found some home filters do a great job of removing contaminants. The GH Research Institute, working with the Arizona Laboratory for Emerging Contaminants at the University of Arizona, tested the effectiveness of a group of filters at removing a group of these emerging contaminants. The water was spiked with low levels of Atrazine (herbicide), BPA (bisphenol A, used in production of plastics and in resins in many metal can liners), Carbamazepine (anticonvulsant), DEET (insect repellent), Estrone (hormone), Fluoxetine (Prozac, an antidepressant), Ibuprofen (pain reliever), PFOA (perfluorooctanoic acid, used to make nonstick-cookware coatings and other products), PFOS (perfluorooctanesulfonic acid, a key ingredient in stain repellents), Primidone (anticonvulsant), Sucralose (artificial sweetener), Sulfamethoxazole (antibiotic), TCEP (flame retardant), Tonalide (fragrance), and Trimethoprim (antibiotic) and the effective removal of contaminants by various commercially available home filters was measured. They found that many were very effective, but the best was the Whirlpool Filter 1 Refrigerator Filter which removed more than 92% for all contaminants over the life of the filter. ZeroWater 8-Cup Pitcher, $35 was found to be the best pitcher type filter. See http://www.goodhousekeeping.com/product-reviews/health-products/water-filters#slide-5 for the full report.

Filtering your tap water and using your own stainless steel bottle saves money, it’s purer than tap water and it helps shrink the global glut of discarded plastic bottles. If your home’s water comes from a public water system, the best way to learn more about your water quality is to read your water supplier’s annual water quality report which should be sent to you annually. If your water comes from a private drinking water well, EPA recommends testing the water regularly for bacteria, nitrates, and other contaminants. At a minimum you should test your drinking water for the 90 SDWA primary contaminants at least every few years and for a shorter list of contaminants including bacteria and nitrates annually.

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Elizabeth Ward

About Me

Elizabeth was awarded an MBA from the University of Pittsburgh and an MS ChE from Polytechnic Institute of NYU, worked as a chemical engineer for both the US EPA in DC, and at DuPont before working in finance and then becoming consultant with Washington Advisors and is the author of "The Lenders Guide to Developing an Environmental Risk Management Program." Elizabeth retired from Washington Advisors and began her volunteer career and is currently the Treasurer of the Prince William Soil and Water Conservation District.

Purpose

Green Risks provides information to understand the natural world especially in our local region. The blog is a mix of technical guidance and interesting information with a slant towards information to live a greener and more sustainable life. You will find articles on a wide range of water and environmental topics including help with water well problems and maintenance, septic systems and regulations, solar energy, low impact development, and many others all with the intent of teaching practical ways to solve problems and revive common sense in our society.