Health Canada says it has discovered almost a dozen more hair smoothing products that contain formaldehyde above the accepted limits.
The products aren't sold directly to the public but are instead used in salons.
Health Canada says it discovered the products "as part of its ongoing work on hair smoothing products."
Formaldehyde is sometimes used in cosmetics as a preservative. Health Canada has capped the allowable level of formaldehyde at 0.2 per cent, but says it found some products with as much as 8.0 per cent.
Formaldehyde is a known irritant, and has been linked to cancer, when inhaled over a long period of time, the agency said.
It said it has received complaints of burning eyes, nose, and throat, breathing difficulties, and hair loss associated with use of professional hair smoothing products.
"Health Canada believes that the reactions are being caused by formaldehyde becoming vapourized during the blow drying and flat ironing stages of the treatment," the agency said in a statement.
It adds that any procedure using products containing high levels of formaldehyde "places clients and stylists at increased risk."
Stylists who use these professional hair smoothing solutions are advised to stop immediately.
Consumers who are aware of salons using products should report it using the incident report form on the Health Canada website.
The following products are listed in the warning (The level of formaldehyde is listed in brackets):
- Keratin Complex Express Blowout by Copomon (Coppola) contains (1.70 per cent)
- Brazilian Keratin Treatment (Mint) - Royal Keratin Professional Line by Keratin Connection (also available in Chocolate and Strawberry) (1.54 per cent)
- Veloce by La Brasiliana (0.35 per cent)
- Zero (Apple) by La Brasiliana (also available in Clear and Mocha) (0.76 per cent)
- Moroccan Hair Treatment by Inoar (2.84 per cent)
The following products contain unacceptable levels of formaldehyde based on data submitted to Health Canada, though the agency a has not yet tested these products:
- Original by La Brasiliana (also available in Original Chocolate)
- Domani by La Brasiliana
- Spruzzi by La Brasiliana
- Brazilian Keratin Treatment by Pro Skin Solutions
- Marcia Teixeira Chocolate Extreme De-Frizzing Treatment EU by M&M International
- Marcia Teixeira Brazilian Keratin Treatment EU by M&M International
A previous advisory named the following products:
- Brazilian Blowout Smoothing Solution by Brazilian Blowout (8.4 per cent)
- Brazilian Keratin Treatment by Marcia Teixeira (1.8 per cent)
- Advanced Brazilian Keratin Treatment by Marcia Teixeira (1.7 per cent)
- Chocolate Extreme De-Frizzing Treatment by Marcia Teixeira (1.6 per cent)
- Keratin Complex Smoothing Therapy Treatment by Copomon (Coppola) (1.8 per cent)
- Global Keratin Taming System Strawberry by Global Keratin (3.0 per cent)
- Global Keratin Taming System with Juvexin Strawberry Resistant by Global Keratin (4.4 per cent)
- Global Keratin Taming System with Juvexin Strawberry Light Wave by Global Keratin (1.4 per cent)
- Pro-Collagen RX Keratin Treatment (2.8 per cent)
- IStraight Keratin (Advanced Keratin Treatment) by IBS Beauty (2.3 per cent)
- Brazilian Thermal Reconstruction by Cadiveu (7.0 per cent)
