During the past year or two, various sources—from special interest groups and green-living guides to ads for water filter manufacturers—have vocally criticized North American consumers' reliance on bottled water. Initiatives like the Food and Water Watch campaign "Take Back the Tap" have described bottled water as a specious marketing scam.
According to "Take Back the Tap" and others, bottled water has a large ecological footprint and is not as stringently (or frequently) monitored for purity and quality as municipal tap water. To all this, add concerns about the prohibitive cumulative cost of bottled water, and you've got a pretty persuasive argument against the product.
A recent article published by a Canadian paper detailing all these points also includes a casual endorsement of water filters from an official: "Those concerned about taste can just use a filter." For many, the use of water filters—from ubiquitous, affordable, mass-market carbon filters manufactured by brands like Brita and PUR to more expensive, state-of-the-art reverse-osmosis systems—gives some peace of mind as well.
Though North American tap water is among the safest in the world, tales of contamination from any number of toxic substances (from lead and mercury to polysyllabic petrochemicals) and any number of sources (from industrial and agricultural pollutants to water treatment systems themselves) still raise anxiety. Water filters seem a cure-all: a way for people to minimize their exposure to hazardous chemicals in water while simultaneously saving pennies and the environment.
Unfortunately, however, it's not quite that simple.
For Tina Clarke, campaign director of Clean Water Action, water filters are only a temporary solution to a tremendous problem. Clarke noted that a properly selected and maintained filter could reduce exposure to some chemicals, but she emphasized the need to overhaul and enforce policies that protect watersheds.
Clarke encourages citizens worried about chemicals to become politically engaged, educated about pollution sources in their own areas, and proactive about enacting conservation strategies in their own households. She also mentioned that people often unwittingly pollute their own water supplies—especially if they use fertilizers or pesticides excessively, and inconsistently with local regulations and manufacturers' instructions.
Press releases from environmental and consumer health groups reiterate Clarke's call for policy overhaul and personal responsibility, but are slightly more pragmatic about political processes. The National Resources Defense Council has published a consumer guide to water filters that tentatively endorses filters as "a good temporary fix for your kitchen faucet." And an Environmental Working Group report published in July, 2007 wasn't so tentative: after collecting tap water samples from regions supplied by the Washington Aqueduct, the EWG "recommend[ed] carbon filtration for all 1.1 million consumers of tap water from the Washington Aqueduct in Washington, D.C. and northern Virginia to dramatically lower levels of toxic disinfection byproducts" present in test samples.
Of course, the EWG recommendation was for citizens in a particular geographic area supplied by a particular water source, and the group—like Clarke and the NRDC—stressed the need to choose a filter carefully. In Clarke's words, "they aren't one-size-fits-all." Different filters remove or reduce different contaminants, and choosing the right one involves research.
Again, an obvious first step for those who want to select a water filter is to learn what pollutants might affect them. They should familiarize themselves with the byproducts from local industries and waste management systems, and should do a little extracurricular reading. The NRDC and the Campaign for Safe and Affordable Drinking Water urge citizens to read annual water quality reports issued by local utility companies; the latter group has published a guide to deciphering the charts and warnings in typical water quality reports (the guide is available online at http://www.safe-drinking-water.org). Both the NRDC and the EWG also offer reports on the safety of water suppliers nationwide. The EWG database is especially detailed (http://www.ewg.org).
The NRDC and the National Agricultural Safety Department encourage citizens to test their own tap water for certain chemicals, especially lead and radon. The NRDC Consumer Guide to selecting a filter urges households with pregnant women or young children to test for lead, as lead contact in water can vary dramatically from house to house. Older homes—in particular, those constructed before 1986, when a nationwide ban on lead pipes and soldering was enacted—may have high concentrations of lead in tap water. And radon, a leading cause of lung cancer, is often found in homes whose water source is a well or a small community industrial plant.
Once you've taken steps to ascertain what contaminants may be in your water, you should research a filter. The NRDC's consumer guide to filters describes common filtration technology, and the National Geographic GreenGuide has published a brand-specific inquiry into the effectiveness of various filters. Both the NRDC and the GreenGuide emphasize the importance of selecting an NSF (National Sanitation Foundation)-certified filter if you want to reduce contaminants as well as improve the taste of water. According to the NRDC, "& as a general rule, look for filters labeled as meeting NSF/ANSI standard 53 and that are certified to remove the contaminant of concern in your water." That "certified to remove" is key: some filter manufacturers may claim that their filter removes a certain contaminant, although the filter has not been certified by the NSF to do so.
Experts also unanimously agree that filters must be replaced as often as recommended for maximum efficacy. According to David Reckhow, a professor of civil and environmental engineering at UMass-Amherst, filters that are "exhausted" may release more and more concentrated potentially harmful substances into drinking water than were present to begin with.
Though several regulatory agencies endorse water filters, the filters are not without their detractors. A New York Times article published in October dealt with controversies surrounding popular carbon filters. Apparently, in the U.S., there are no measures in place to recycle replaceable filter cartridges. A California resident, Beth Terry, has started a petition (TakeBacktheFilter.org) intended to pressure filter manufacturer Brita to implement recycling plans. And though a professor quoted in the Times article noted that the "water filter is a miniscule bit of waste" compared to water bottles, they're non-biodegradable waste nonetheless.
Those worried about the state of tap water should notice that neither of the water experts profiled in this article filter their drinking water. For Clarke, a whole-picture approach to drinking water protection is of greatest importance. And Reckhow pointed out that often media coverage of threats to public health can be alarmist or disproportionate; he considers threats posed by tap water contaminants to be fairly miniscule for most of the population.