Water Talk – 1,4-Dioxane in drinking water

We have developed guidelines for 1,4‑dioxane in drinking water to protect the health of Canadians. Learn about the health effects of 1,4‑dioxane and how to reduce your exposure if it is present in your drinking water.

On this page

• 1,4‑dioxane in drinking water
• Health effects of 1,4‑dioxane in drinking water
• How to reduce your exposure to 1,4‑dioxane in drinking water
• Limit for 1,4‑dioxane in drinking water in Canada

1,4‑dioxane in drinking water

1,4‑dioxane is a human‑made chemical that is not found naturally in the environment. It is released in the environment mainly from:

• leaks from landfills
• wastewater discharges
• chemical waste disposal

It can be present in:

• air
• soil
• food
• water
• consumer products
• industrial and commercial solvents

1,4‑dioxane is generally not found in drinking water supplies in Canada. In some cases, it has been found in groundwater located near landfills and industrial sites.

The only way to know if you have 1,4‑dioxane in your drinking water is to have your water tested. Contact your local public health authority for advice if you are interested in testing your drinking water, particularly if you have a private well.

Health effects of 1,4‑dioxane in drinking water

Drinking water that has high levels of 1,4‑dioxane may affect your liver and kidneys.

If you have concerns about your drinking water or health, contact your public drinking water authority or public health authority for more information.

How to reduce your exposure to 1,4‑dioxane in drinking water

You can install a reverse osmosis unit directly at the tap to help remove 1,4‑dioxane.

Make sure that any unit or system you buy is:

• certified as meeting the NSF International standard, NSF/ANSI Standard 58 (reverse osmosis)
  • even if no residential treatment device is certified specifically to remove 1,4‑dioxane, this standard ensures the safety and performance of the device
• installed and maintained according to the instructions given by the manufacturer.

To make sure the treatment unit is working, you should conduct regular testing on:

• the water at the tap
• the water entering the treatment unit

Bathing and showering in water that contains 1,4‑dioxane should not be a health risk.

If you are pregnant or breastfeeding

You should have your drinking water tested if you are pregnant, breastfeeding or preparing infant formula and suspect that your drinking water may contain 1,4‑dioxane. If 1,4‑dioxane levels are above the limits, you may wish to:

• use an alternate source of drinking water
• install a treatment unit to remove 1,4‑dioxane

Limit for 1,4‑dioxane in drinking water in Canada

We worked with provinces and territories to set a maximum level for 1,4‑dioxane in drinking water. The maximum acceptable concentration (MAC) is 0.050 milligrams per litre (mg/L). This level protects the health of all Canadians, including the most vulnerable members of society, such as infants and children.