Health Canada is warning Canadians and their health-care providers that thermography machines  are not approved for use in Canada for breast cancer screening.

The department says it is not aware of any scientific evidence that supports use of the thermal imaging machines as a screening tool for early detection of breast cancer.

Health Canada says there could actually be a potential risk to women if they rely on thermography results.

The agency is  recommending that women who have used thermal imaging for breast screening contact their doctors for appropriate followup and testing.

Health Canada says it is contacting makers of the devices to ensure they know that it is illegal to advertise or sell these types of machines to screen for breast cancer in Canada.

The department is also working with the Canada Border Services Agency to stop any unlicensed devices from entering Canada.