NEWS

Bottle vs. tap: what type of water is best?

09/26/2014 05:00 EDT | Updated 11/25/2014 05:59 EST
Recent reports of drugs in our drinking water might have some people heading for the bottled water aisle of their nearest grocery store, but in most parts of Canada, choosing bottled water over tap is a matter of taste or convenience, not health.

Unless you live in a community that lacks water treatment facilities — which, even after the Walkerton water crisis of 2000, is still a reality for some Canadians, including many First Nations — chances are the water coming out of your tap is perfectly safe to drink. 

That didn't stop Canadians from purchasing 2.4 billion litres of bottled water last year, or about 68 litres per capita, according to a market analysis by Euromonitor International.

The bottled water industry is worth more than $170 billion, and North Americans are some of its most avid consumers, so much so that in the U.S., bottled water has surpassed milk and beer in terms of volume sold. In Canada, three out 10 households drink bottled water at home, according to Statistics Canada.

We take a look at some factors to consider when deciding between tap and bottled water.

Water quality

Tap water is regulated by Health Canada and the provinces and territories. The Guidelines for Canadian Drinking Water Quality​ spell out the maximum levels of potentially harmful substances that are allowed in drinking water. Municipalities test their water sources constantly to make sure they are within these limits.

The City of Ottawa, for example, conducts more than 125,000 water quality tests a year. Toronto tests water samples every four to six hours and checks for more than 300 potential chemical contaminants.

The results of this monitoring are generally easily accessible to the public, often on city websites or by request.

Bottled water is not subject to the same guidelines because it is classified as a food and falls under the Food and Drugs Act. Aside from arsenic, lead and coliform bacteria, the act does not set limits on specific contaminants but says simply that food products cannot contain "poisonous or harmful substances" and must be prepared in sanitary conditions.

Spring and mineral water is subject to a few more rules: it must be fit for human consumption at the source and can't be treated in any way that would modify its composition, other than by adding carbonation, ozone or fluoride.

Self-policing industry

Monitoring of water quality in the bottled water industry is "essentially voluntary and internally regulated," a 2009 study by the Polaris Institute, an Ottawa-based non-profit environmental advocacy group, found.

​Bottled water producers insist they perform a comparable degree of testing on their water as municipalities, but the results do not have to be made public — although some companies do post sample water quality analyses online.

The Canadian Food Inspection Agency does conduct inspections of bottled water plants, but the Polaris Institute found that these are done on average once every three years.

There have been efforts to introduce stricter guidelines, but these have been stalled for years, leaving the industry to police itself.

Companies that belong to the Canadian Bottled Water Association (CBWA), which represents about 85 per cent of the industry, are supposed to follow certain best practices when it comes to monitoring water quality and submit to annual inspections by a third party, but compliance is voluntary and self-policed.

Provinces do have leeway to impose stricter regulations, but so far, only Quebec has done so. Its bottled water regulation sets limits on metals and other contaminants and requires labels to specify where the water cam.

Labels don't tell full story

Outside of Quebec, labels on bottled water that is not spring or mineral water don't have to specify the source of the water, even if that source is your municipal water supply.

The CBWA says less than eight per cent of bottled water sold in Canada comes from municipal sources, but in the U.S., scientist Peter Gleick has estimated it's as much as 45 per cent.

Some of the biggest manufacturers of bottled water — Coca-Cola, ​Nestlé and PepsiCo — have come under fire in recent years for not revealing that popular brands like Dasani, Poland Spring and Aquafina are essentially treated tap water. Some, like Aquafina, have since put that information on the label, but it's not a requirement — as long as the label isn't explicitly misleading.

Bottled water labels do have to specify how the water was treated and whether it contains fluoride and must list any added ingredients. Mineral and spring water must specify the mineral salt content while water that has had the bulk of its minerals filtered out must be labelled "demineralized."

Some brands specify an expiration date, although this is not required, and there is disagreement on whether water — if kept sealed and stored in cool conditions that don't promote the growth of bacteria — can ever "expire." The industry has said bottled water has a shelf life of two years, but Health Canada suggests replacing water after one year while the U.S. Food and Drug Administration considers it to have an indefinite shelf life.

No clear health risks

Health Canada considers all bottled water that meets the standards set out in the Food and Drugs Act "comparable from a health and safety perspective" and says the water sold in Canada is generally of good quality and doesn't pose any health hazard.

Illnesses associated with bottled water are rare, but like tap water, it can become contaminated. The Polaris Institute found that there were 29 recalls of 49 bottled water products between 2000 and 2009 because of contamination — by everything from bacteria to mould to arsenic and "extraneous material" such as glass. 

The Canadian Food Inspection Agency was unable to provide more current figures, but one recent case was the 2013 recall of water from Blue Glass Water Co. (Caledon Clear Water Corp.) because of bacterial contamination.

In 2004, a voluntary Dasani recall in the U.K. attracted international attention after Coca-Cola found levels of bromate in the water exceeded legal limits.

The lack of fluoride in bottled water, which usually contains none or lower levels than tap water, is another potential health concern that has been raised by health professionals who believe it helps prevent tooth decay.

Others have raised the point that water that has been demineralized — either through commercial or household filtration — might deprive those who drink it of the beneficial effects of essential minerals such as magnesium and calcium.

There have also been concerns over the potential leaching of antimony trioxide, a suspected carcinogen used in the manufacturing of the polyethylene terephthalate plastic (known as PET or PETE) that water bottles are made of, but studies by Health Canada and others have shown that the levels found in bottled water were not a health risk. 

Bisphenol A, the controversial compound found in some plastics, is not a concern with PET water bottles. 

What about the drugs?

Many of the companies that have successfully commodified tap water have done so by claiming their product tastes better than what comes out of your tap.

To achieve that "improved" taste, bottlers often use multi-step filtration processes that remove naturally occurring minerals like magnesium, calcium and sodium and don't leave the same odour and taste as the cheaper chlorine disinfection used by municipal water treatment systems.

These include methods such as ozone and UV disinfection, carbon filters and reverse osmosis. 

Ozonation and carbon filters can theoretically filter out organic compounds like the pharmaceuticals detected in some drinking water, but bottled water is generally not tested for such compounds. Household carbon filters can serve the same purpose for tap water.

Mineral and spring water, which comes from groundwater rather than surface water like lakes and rivers, is less susceptible to such chemicals, which generally show up in wastewater effluent and have not yet been shown to be a serious health risk. Municipal water can come from groundwater or surface water.

Cost

Bottled water costs several thousand times more than tap water (about $2.50 for a 500 ml bottle in your local vending machine compared to fractions of a penny per litre from the tap), and much of the water corporations sell is obtained on the cheap from public water sources.

Many provinces do require bottlers to obtain permits to extract this water, but charge very little for the privilege. Nestlé pays a mere $3.71 for every million litres of water it draws from a well near Hillsburgh, Ont., and has permission to withdraw 1.13 million litres of groundwater per day.

Ontario requires all industrial or commercial facilities that use more than 50,000 litres a day to pay the $3.71 fee and obtain a permit, but not all provinces do. Until recently, B.C. did not regulate industrial groundwater use and allowed ​Nestlé to extract millions of litres a year from a well in Hope, B.C., for free.

Environmental impact

Although many companies have tried to cut down on the amount of plastic they use and increase the proportion of recycled and compostable materials, the industry still generates significant waste and consumes water and fossil fuels in the process of bottling and transporting its products. 

The CBWA says plastic bottles account for only one-fifth of one per cent of landfill, but once there, they can take hundreds of years to decompose.

About 70 per cent of PET drink containers in Canada are recycled, according to the Canadian Beverage Association, although recycling rates vary by province. 

Some of that plastic waste gets shipped abroad for recycling — creating more greenhouse gases in the process.

(You might be tempted to reuse your empty water bottle to give it a second life, but health experts say reuse increases the risk of bacteria and the leaching of potentially harmful chemicals.)

The industry says it barely makes a dent in Canada's fresh water supply and that it only takes 1.3 litres to make one litre of bottled water, but other estimates have placed it as high as three litres.

The Pacific Institute in California has estimated that bottled water is up to 2,000 times more energy-intensive than tap water. In 2006 alone, bottling water for U.S. consumption used the energy equivalent of 17 million barrels of oil and produced 2.5 million tons of carbon dioxide, it found.

Increasingly, federal and local governments, as well as some university campuses, are finding those costs too high and are adopting bottled water bans or special surtaxes on the sale of bottled water. Toronto has banned the sale of bottled water at all municipal parks and facilities. San Francisco's ban even extends to food trucks regulated by the city.

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