Health Canada Tap Water Survey

Some recent news stories have raised concerns about a survey that Health Canada is conducting on tap water and water treatment facilities in Canada.

Canadians should rest assured that drinking water in Canada is amongst the safest in the world, and that maintaining clean drinking water is a priority for the Government of Canada.

The survey is part of a routine testing and monitoring program designed to give Health Canada a better understanding of the presence of various disinfection by-products and other potential contaminants which may be found in drinking water.

The results, which are expected to be released in 2011, will provide Health Canada with information to determine whether new guidelines should be developed, or whether measures in addition to those already taken by Government need to be put in place to reduce the risks these substances may pose.

Canada's tap water remains a safe and economical source of clean drinking water. Health Canada encourages Canadians to drink plenty of water each day as an important part of maintaining good health.

Questions and Answers

• Should I be concerned about the safety of my tap water?
• Why is Health Canada conducting this survey?
• Why is this survey being conducted now?
• How many substances are being tested?
• What are disinfection by-products and how are they formed?
• Why, as part of this survey, is Health Canada studying pharmaceuticals in water?
• How many sites will be tested?
• What does the testing process involve?
• What will the government do with the study results?
• When will the results be made available?

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Should I be concerned about the safety of my tap water?

No. Drinking water in Canada is amongst the safest in the world. All provinces and territories have comprehensive regulatory regimes in place to ensure the safety of drinking water, including appropriate treatment. This survey is part of Health Canada's routine monitoring processes.

Why is Health Canada conducting this survey?

As steward of the Guidelines for Canadian Drinking Water Quality, Health Canada works closely with the provinces and territories on research that promotes the highest standards of water quality.

Health Canada has initiated this research as part of its ongoing work, to ensure that the guidelines continue to ensure the greatest possible safety for Canadians.

The data gathered through this research will better enable the department to set priorities for drinking water guideline development, and will help the Government identify whether new guidelines should be developed, or whether measures in addition to those already taken by Government, need to be put in place to reduce the risks these substances may pose.

Why is this survey being conducted now?

Health Canada is being proactive in undertaking this work. The department undertakes such studies as part of its processes to identify the presence of potential contaminants in drinking water and the levels to which Canadians may be exposed. Similar but smaller surveys were conducted in 1976-77 and 1993. These studies are used to help determine priorities for guideline development.

How many substances are being tested?

More than 100 different water quality parameters will be analyzed during the study in approximately 60 water treatment facilities across the country over two years (2009 and 2010).

Parameters under study include a variety of disinfection by-products (54 in total), some new and emerging contaminants (e.g., selected pharmaceuticals, personal care products, Bisphenol A, etc.), various inorganic substances, and general water quality.

What are disinfection by-products and how are they formed?

Disinfection by-products (DPBs) form when disinfectants used to treat the water, such as chlorine, react with naturally occurring organic matter (e.g., decaying leaves and vegetation).

The use of disinfectants in the treatment of drinking water has virtually eliminated waterborne diseases, because disinfectants such as chlorine can kill or inactivate most microorganisms commonly found in water. The majority of drinking water treatment plants in Canada use some form of chlorine to disinfect drinking water, to treat the water directly in the treatment plant and/or to maintain a chlorine residual in the distribution system to prevent bacterial re-growth. The health risks from disinfection by-products are much less than the risks from consuming water that has not been disinfected.

Why, as part of this survey, is Health Canada studying pharmaceuticals in water?

Health Canada is conducting this survey as part of its ongoing work to ensure the safety of drinking water in Canada. The survey focuses on newly emerging disinfection by-products as well as other potential contaminants such as pharmaceuticals. The comprehensive nature of this survey provides an opportunity to collect baseline information on the presence of chemicals entering drinking water sources, as well as their fate during drinking water treatment.

How many sites will be tested?

The number of sites in the study is limited to approximately 30 sites per year, due to the complexity of the testing program and the timing required for sampling and analysis.

Thirty-four sites have been identified for the 2009 sampling, which began in January 2009. Sites were chosen with the assistance of the provinces and territories.

Utilities participating in the study were chosen to be representative of communities across Canada, based on criteria such as size of population served, type of treatment technology/processes, and type of source water (ground vs. surface).

What does the testing process involve?

At each of the sites (approximately 30 sites per year) a number of water samples will be collected for various analytical tests. Raw water and treated water samples will be taken and, for some parameters, up to three additional samples will be taken from various areas within the distribution system. Each site will be sampled twice, once under winter conditions and again during the summer. The samples will be preserved and shipped to the laboratories for analysis.

What will the government do with the study results?

The results will provide the Government with updated exposure data to be used in the preparation/update of Guidelines for Canadian Drinking Water Quality. The data will also be used to set priorities for drinking water guideline development, and in some cases may be used to set priorities for additional measures to reduce exposures.

The results of the study will also be shared with provincial and territorial governments in a timely manner, as they are responsible for the management of drinking water, including treatment, within their jurisdictions. If levels of any contaminant measured in the study are found to pose a risk to human health, Health Canada would work with the provinces and territories in mitigating the risk.

When will the results be made available?

Sampling and analysis of the final 30 sites will be completed during the summer of 2010. The results of the entire survey are expected to be released in 2011.