Votre eau est-elle potable?

Globalement, 30 000 personnes meurent chaque jour d'une maladie attribuable à l'eau. Dans les nations en voie de développement, 80 % des maladies proviennent d'eaux contaminées. 

Ici au Canada, à cause de plusieurs facteurs, la qualité de l'eau peut véritablement inquiéter les citoyens. Une façon économique et efficace de déterminer la qualité de l'eau d'une maison est de la faire vérifier.

Depuis quelques années, plusieurs types de tests de la qualité de l'eau potable sont disponibles aux consommateurs partout au Canada. 

Il est important de vous assurer que le test que vous choisissez suit les Directives canadiennes sur la qualité de l'eau.

Les principaux polluants incluent : les bactéries, le plomb, les pesticides, le chlore, les nitrates et les nitrites. Il est aussi utile de déterminer l'acidité et l'alcalinité de l'eau. 

L'eau provenant de chaque robinet devrait être vérifiée au moins une fois par an, et deux fois par an si vous obtenez votre eau d'un puits.


Is Your Drinking Water Safe?
A Guide to Water Testing

Brett Hopkins
Silver Lake Research - Watersafe

March 2002

lobally, 30 000 deaths occur daily from water-related diseases. In developing nations, 80% of illnesses occur due to contaminated water . Here in Canada, due to a number of factors, water quality can present a very real concern for citizens.

Canadian Water Quality

Canadian water quality is
determined by the Canadian
Water Quality Guidelines
issued by the government's
Subcommittee on Drinking Water. These guidelines recommend maximum acceptable levels in drinking water for physical, chemical, radiological and microbiological substances. Water that contains contaminants in amounts in excess of these maximum safety levels can potentially cause adverse health effects. These guidelines are used by government agencies to effectively assess water quality problems and are subject to review and revision, as new information becomes available.

Recently, these guidelines have come under increasing criticism because, unlike in the United States, where the United States Environmental Protection Agency's (USEPA) maximum contaminant levels in water are standards enforced by law, Canada's Water Quality Guidelines are in effect recommendations which do not necessarily have the force of law behind them. Because of this difference, responsibility for water quality rests with the administrators of the myriad local and municipal water systems across Canada.

In recent years, some of these water systems have proved themselves to be ineffective in preventing contamination of the water supply. In May 2000, this ineffectiveness was most disastrously evident in Walkerton, Ontario, where E. Coli bacteria contamination of the town water supply resulted in seven deaths and over 2 000 illnesses . In 2001, almost 400 cases of contaminated water were reported in Ontario alone, affecting towns, schools, trailer parks and homes . In North Battleford, Saskatchewan, last spring thousands of residents became ill when the water supply became contaminated by the parasite cryptosporidiosis. As of March, year?, 50 communities in Saskatchewan have been under water advisories and two under emergency boil water orders .

Most of these cases occur in areas serviced by small water systems that don't have the funds to purchase or operate the high-quality filtration systems in use by the larger municipal water systems in Canada's larger cities. Millions of people across Canada rely on these small systems for their water (there are 5 000 small water systems in Ontario alone ).

Because of these factors, it is imperative that Canadians know what is in the water they drink.

Water Testing at Home - 
What You Can Do To Eliminate the Unknown

Water testing is an inexpensive and effective way of determining the quality of home drinking water. Many home drinking water test kits have become available to the consumer in recent years and can be found in local hardware stores, health food stores and supermarkets across Canada. Many of these tests are simple cardboard strip tests that, after being exposed to water, inform the user of the level of contamination by color change. Home tests are now available for bacteria, lead, pesticides, nitrates, nitrites, arsenic, chlorine, pH and hardness and can be purchased as individual tests or "all in one" test kits that include combinations of tests for any or all of the above contaminants.

It is important to make sure that the test you decide to use is calibrated to Canadian Water Quality Guidelines. Most calibrated tests will list this on the packaging. These tests will also include information on what to do if your water is contaminated.

Water should be tested at least once a year at all faucets in the home and twice a year if you rely on a well for your water. If you have had problems with your water previously, testing your water at least once every 1-2 months is recommended.

Here are brief descriptions of some major contaminants and their effects:


Toxic bacteria may enter the water supply from human or animal wastes or natural sources. Multiplying rapidly, they may release a variety of potent, damage causing molecules called endotoxins. Many strains of bacteria are not toxic, but some can cause very serious illness. Even mild cases can result in diarrhea, vomiting, cramps, and other gastrointestinal symptoms. Since contaminated water may not taste or smell bad, most cases of water-borne disease are not likely to be identified as such.


Since lead was used extensively in plumbing until the 80's, many homes and buildings have pipes and plumbing fixtures that contain lead. Lead can leach from pipes into household water, making this plumbing a major source of toxic lead poisoning. Lead poisoning is so toxic that even very low levels can be dangerous. Lead consumption and poisoning has been linked to learning disabilities, muscle and bone disorders and kidney damage. Lead levels should be tested at each faucet in the home, especially if plumbing fixtures could date from the 80's or before.


Pesticides are chemicals used to eliminate weeds, insects and other harmful elements in crops. Atrazine and simazine are two of the pesticides most commonly found to contaminate drinking water. Millions of pounds of these two chemicals are introduced into the environment each year as herbicides and left to potentially leak into the soil, and then into groundwater, lakes and rivers that are sources of drinking water. These chemicals are so toxic that the USEPA-mandated maximum contaminant level in drinking water is equivalent to less than one drop in a large swimming pool.


Chlorine is used extensively to purify water. The consumption of chlorine in very small amounts will likely not cause serious harm, but its by-products, including chloroform, which are produced when chlorine mixes with organic matter, can be extremely harmful. Drinking water with high levels of chlorine by-products has been linked to some forms of cancer.

Nitrates & Nitrites

When animal and human wastes or field fertilizers come into contact with water, they produce nitrates and nitrites. Both are dangerous to children and can cause "Blue Baby Syndrome," a lethal form of birth defect in infants.

pH and Hardness

PH and Hardness do not directly cause harm but can cause a variety of secondary effects if not treated. If water acidity is too high, corrosion can leach out lead from pipes and plumbing (see lead above), as well as damage plumbing and water heating systems. Water hardness is primarily caused by calcium and magnesium compounds. These chemicals are not easily detected, but the negative effects include scaling of pots and pans and, if left untreated, damage to plumbing and water heaters.

If your water tests positive for any of the above contaminants, the USEPA has a Safe Water Hotline accessible from the USA and Canada, at 1-800-426-4791. The agency can give you expert advice on what steps to take to rid your water of dangerous contaminants.

Links and Information

Silver Lake Research specializes in developing, manufacturing, and marketing do-it-yourself test kits for contaminants in food and water supplies. These easy-to-use kits produce results that are calibrated to the EPA's exacting Maximum Contaminant Level (MCL) standards. Silver Lake Research also manufactures test kits for food safety applications, used by processors, veterinarians, and livestock producers. For more information about Silver Lake Research, call 1-888-438-1942, log on to www.watersafetestkits.com or write to:
PO Box 686, Monrovia, CA 91017.