The global consumption of bottled water has increased an astounding 57% over the past 5 years to 154 billion litres in 2004 and is on the verge of becoming the number one consumed beverage in North America. But isn’t this multi-billion dollar industry supplying the same stuff we get out of the tap for free? One of the reasons for the increase in bottled water consumption is a seeming lack of confidence in many municipal water supplies. With incidents like the E.coli outbreak in Walkerton in 2000 and daily boil water advisories around the country, it is no wonder that many people have turned to bottled water for what they see as a “safe” and convenient alternative to tap water. After all, is it really feasible to treat 100% of tap water to the point that it is risk-free for drinking when less than 0.5% of tap water is used for drinking?

But is bottled water really a “safer” choice? Wise consumers focus on both water purity, which is determined by the level of (usually invisible) non-H2O substances in the water as well as water disinfection, referring to the method and effectiveness in destroying bacteria (such as E.coli), viruses and other water-borne microbial pathogens (like cryptosporidium). The most common methods of disinfection today are chlorination, ultraviolet (UV) light, boiling and ozonation.

Chlorination, used predominantly by municipal water suppliers, can be recognized by its strong smell and taste. Chlorination actually kills only one third of known waterborne pathogens and has been associated with producing suspected cancer-causing by-products known as trihalomethanes (or THMs) that cannot be filtered out by conventional home filter systems. Ultra-violet (UV) light disinfection uses special lamps to kill water-borne bacteria. Many (especially spring water) bottlers use this method because it has little effect on the taste of the water and does not contribute to the formation of dangerous by-products. The downside: UV light is one of the least effective disinfection methods. Boiling destroys many (but not all) of the potential water-borne pathogens, but it is inconvenient and can further concentrate some harmful chemicals like nitrates or lead that may be present in the water.

Ozonation does not affect the smell or taste of the water and is the most effective disinfection method but, it too, can produce carcinogenic by-products such as bromate when introduced to water that is not completely pure (like spring water or reverse osmosis water).

What about minerals in water? Aren’t they healthy? Fact is that “good” minerals that the body can readily use are found in very small trace amounts in water and are always outnumbered by “bad” minerals and compounds that can also form the carcinogenic disinfection by-products discussed earlier.

What about fluoride? Most bottled water does not contain fluoride, but the ongoing controversy over whether fluoride is good or bad is evident from the websites of the Canadian Dental Association (www.cda-adc.ca) as well as groups such as The Fluoride Action Network (www.fluoridealert.org). However, fluoride supplements are readily available to consumers.

So what is a consumer to do? Ask questions! Find out what type of water is in the bottle, where it comes from, if and how it is purified, how it is disinfected, why it has or doesn’t have any taste, how it is bottled, who bottled it and when it was bottled. Ask for proof that it is purer (and not only better-tasting) than tap water before you shell out your hard-earned cash. Bottom line: Be cautious and choose wisely!