GUEST COLUMN / ENVIRONMENT
ANOTHER LOOK AT TAP WATER
Bottled water is being knocked as environmentally wasteful. However, the arguments have missed the point of unregulated contaminants in municipally provided water, writes GORDON McEVOY
I am a licensed public drinking water system operator. I drink bottled water; the good stuff - artesian or spring mineral water. Lately, tap water proponents are knocking bottled water as outlandishly expensive and environmentally wasteful (petroleum is required to produce the plastic, which then unnecessarily loads already stressed landfills). Those refusing perfectly good tap water while millions around the globe lack access to clean water sources are accused of no less than shameful eco-decadency.
Tap water is the new drink of the "politically correct". However, anti-bottled water arguments have failed to clearly outline important distinctions necessary for consumers to make educated decisions regarding their personal health.
Tap water in the United States is argued as safer than bottled water due to the stricter health-based regulations imposed. However, despite overwhelming public water utility compliance to established regulations, tap water in the US has been found to be loaded with unregulated contaminants.
The Environmental Working Group (EWG), a Washington DC-based nonprofit research organisation, analysed millions of water quality test results on file, as required by utilities under the Safe Drinking Water Act. The EWG discovered that between 1998 and 2003, 141 unregulated (therefore legal) contaminants were identified flowing from public taps across the country - including pesticides, ammonia, industrial plasticisers, and the rocket fuel component perchlorate. According to the EWG, of the confirmed unregulated contaminants, "52 are linked to cancer, 41 to reproductive toxicity, 36 to developmental toxicity and 16 to immune system damage".
The EWG asserts these findings underestimate harmful pollutants in America's tap water, due to limited federal monitoring required for pollutants suspected or known to exist in source and tap waters. For example, disinfection of tap water is necessary for eliminating waterborne disease. However, when organic pollution reacts with powerful oxidising agents used as disinfectants like chlorine or ozone gas, potentially harmful by-products are known to form.
Disinfection by-products (with ominous names like trihalomethanes and haloacetic acids) have been linked to cancer and reproductive toxicity. The EWG points out that while the US Environmental Protection Agency (EPA) regulates a handful of chemical disinfection by-products, scientists have identified up to 600 different types of these chemicals in treated tap water.
The EWG concludes that the EPA has failed to comprehensively determine what pollutants exist in America's tap water and subsequently set enforceable standards for those that have been found.
Supporting this charge, a 2003 National Resource Defense Council (NRDC) review of tap water quality in 19 American city water supplies concurs that, though relatively few cities are in violation of national drinking water standards (infractions of tap water rules were found in five major US cities over a two-year period), this achievement results from weak federal standards rather than low contaminant levels. The NRDC warns that tap water contaminants in some cities might pose health risks to pregnant women, infants, and young children - due to source water pollution, aging treatment plants, and deteriorating distribution systems.
Drink to our health?
The EPA currently regulates about 100 tap water contaminants. However, according to recent nationwide research performed by the United States Geological Survey, a potential universe of thousands of "emerging" contaminants - including residues from everyday products like caffeine, nicotine, artificial fragrances, insect repellants, and micro-bacterial agents used in soaps - threatens US lakes, rivers and underground aquifers. In fact, research has recently revealed an entire new category of water pollutants: pharmaceutical waste.
Municipal drinking water plants draw from these potentially contaminated sources. Operators chemically treat this raw water and pump the resulting potable product to taps of homes and businesses. However, public drinking water treatment plants are not designed specifically to remove residues from synthetically-engineered pharmaceutical products. Therefore, in some cases, these potentially harmful compounds may pass directly through the treatment process.
Independent studies (separate from tests required by the Safe Drinking Water Act) have discovered trace pharmaceutical waste in tap water in various US cities, including anti-cholesterol drugs, hormonal supplements, painkillers, and antibiotics such as tetracycline.
Scientists are collectively unsure of any human health effects associated with consuming minute quantities of pharmaceutical waste in drinking water. However, known hormone system disrupting chemicals, such as estrogen-mimicking compounds, are now linked to developmental and reproductive changes in fish (specifically an alarming "feminisation" effect seen in male fish).
The EPA's website acknowledges that human fetal exposure to low levels of unintended medicines in drinking water requires more investigation. Furthermore, a specially formed EPA committee has recommended a staggering list of over 60,000 chemicals for hormone system disruption screening alone.
Drawing from the Chao Phya
Bangkok draws its tap water mainly from the Chao Phya River; a source likely containing similar contaminants now confirmed in American waters. The Bang Khen treatment plant operated by the Bangkok Metropolitan Waterworks Authority (BMWA) utilises aggressive, yet primarily conventional treatment processes: coagulation, sedimentation, filtration, and disinfection with chlorine.
Preliminary investigations by the US EPA have revealed that conventional treatment processes are generally ineffective at removing trace pharmaceutical contamination. The reverse-osmosis treatment process (used to desalinate sea water) has been shown to remove a significant portion of certain pharmaceutical compounds. However, Bangkok's tap water is not treated by reverse osmosis.
The BMWA maintains that its treated water exceeds tap water safety standards set by the World Health Organisation (WHO). Impressive as this feat may be (especially when considering the state of the Chao Phya River), WHO's drinking water standards are similar to those set by the US EPA.
The Chao Phya River is certainly polluted by more than the 100 or so contaminants covered by WHO's standards. Therefore, we might assume that, similar to municipal tap water in the US, Bangkok's tap water is contaminated to some degree with unknown types and concentrations of unregulated contaminants, including pharmaceutically-active compounds (think Viagra).
Pepsi Company recently disclosed that their popular Aquafina bottled water is actually ordinary tap water. However, not all bottled water is equal. Artesian or spring bottled groundwater is likely "pure" compared to most tap water sources, because it typically derives from more protected or virgin ecosystems with much lower potential for impact by unregulated pollutants or chemical disinfection by-products.
Evian brand, for example, originates as snowmelt high in the Alps and slowly filters through thousands of feet of mountain before day-lighting clean enough to negate the need for chemical treatment prior to bottling.
Going green is not as black and white as we like to think. Perhaps the eco-police should scrutinise more hedonistic consumptive pleasures - like alcohol, tobacco, skin-whitening lotion, or even microwave popcorn.
Drink all of the recycled tap water you want. I'm sticking to Perrier, and I feel fine.
Gordon McEvoy is a currently licensed (Colorado, Class "A") public water system operator.