The Alberta Centre for Toxicology tests drinking water to make sure it’s safe to drink. They use the
Guidelines for Canadian Drinking Water set by Health Canada to report safe levels of substances in drinking water that can be harmful to your health. To understand your drinking water test results, use the information below.
Some of the results are reported using these categories:
Maximum acceptable concentration (MAC) is the highest amount of a substance in drinking water that is safe for a person to drink. This value is set to protect an average person from a substance in drinking water, if they drink 1.5 litres of water each day over 70 years.
Aesthetic objective (AO) looks at substances that can change the taste, odor, and appearance of drinking water. The AO is the level of a substance used to decide if people will use or drink the water.
Operational guidelines (OG) are followed when a substance in the water may affect water treatment or damage pipes and plumbing fixtures. An OG is not used to test private well water supplies.
The following is a list of metals that are tested for in drinking water. If your water testing shows high levels of any of the following substances, call your local public health inspector. They can give you information about treatment devices for your home water supply.
Talk to your doctor if you have questions about substances in drinking water and if they could affect your heath.
Antimony levels higher than the MAC may cause small changes in organs, including the thymus, kidney, liver, spleen, and thyroid.
Arsenic levels should be kept as low as possible. Drinking water that has arsenic levels above the MAC may increase the risk of:
Barium levels above the MAC may increase the risk of developing high blood pressure and heart disease.
People are mostly in contact with boron through food.
Drinking water that has boron levels above the MAC may increase the risk of reproductive problems in men.
Cadmium levels above the MAC may increase the risk of kidney damage and softening of bones.
Drinking water is tested for chromium 6 (VI). Chromium 6 can cause lung cancer or damage to other organs.
We need chromium 3 (III) to stay healthy so it’s not included in drinking water testing.
When high levels of lead are found in Alberta drinking water, it usually has come from solder or lead pipes.
Higher levels of lead in drinking water can cause:
Contact with high levels of lead over many years can cause stomach and lung cancer.
We need a small amount of manganese in our diets to stay healthy. Drinking water high in manganese can lead to:
People who are very young, pregnant, older, and those with liver disease have the highest risk of developing these health problems.
Infants also have a high risk of developing these problems if they drink formula made with water that has high levels of manganese.
The amount of mercury in drinking water is usually below the MAC.
Canadians are exposed to mercury mostly from food, especially those who eat a lot of fish and seafood.
Mercury levels above the MAC may cause nerve problems that can’t be cured.
It may also be found in unleaded brass (to replace lead).
We need a small amount of selenium to stay healthy. We get most selenium from food.
Eating food or drinking water with high levels of selenium can cause:
Strontium can replace calcium in bones.
Strontium levels above the MAC may raise the risk of rickets, which is a bone disorder that may:
The risk is highest for babies because their bones are growing so quickly.
Water with zinc levels higher than the AO will look cloudy or milky, and have a greasy film when boiled.
Health Canada has not found any health concerns related to drinking water with zinc.
If your drinking water supply comes from a system that uses galvanized pipes, run your tap for 1 minute before drinking the water.
The following metals aren’t included in the Guidelines for Canadian Drinking Water Quality. At this time, Health Canada has not found that these metals are related to any health concerns.
Alberta Health Services is collecting information about these trace metal levels to better understand if they get into our drinking water from natural causes or industrial activity.
For more information about drinking water, visit:
Alberta Health Services – Information for your Home
Alberta Environment and Parks – Working Well
Current as of: March 5, 2021
Author: Environmental Public Health, Alberta
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