Health Canada issued a warning that the hair smoothing product Brazilian Blowout Solution contains a dangerous amount of formaldehyde. (CBC)

A Cochrane woman is joining a class action lawsuit against a hair-straightening procedure that used formaldehyde.

Terry Balcaen said a few years ago she had a Brazilian Blowout and had a painful, long-lasting reaction to the hair treatment.

“As soon as she applied them it was burning, burning, burning my scalp basically,” Balcaen said. “My eyes started watering and I thought get this off of me, this is awful.”

Brazilian Blowout Solution, which promises to smooth frizzy hair, contains 12 per cent formaldehyde, far exceeding the allowable level of 0.2 per cent in cosmetics.

Health Canada pulled the product in 2010.

Balcaen said two weeks after applying the product her hair took a turn for the worst.

“Just clumps and clumps of my hair were just falling out,” she said. “One of my co-workers said it looked like I had taken scissors to the top of my hair.”

Merchant Law Group Attorney Darren Williams said the lawsuit involves people who suffered burns, hair loss and worse.

“It's not about I went to the stylist today to make myself pretty, and ‘Hey I'm not as pretty as I am supposed to look,’” Williams said. “That's not the point at all. We have people who went home, could no longer work because they had trouble breathing.”

“We have people who can't use perfumes or be exposed to other chemicals now because of their reaction to this formaldehyde.”

Williams said he expects thousands of people will sign up for the class action lawsuit.