Permanent hair dyes and perming treatments (at salons) may contain banned aromatic amines called toluidines that have carcinogenic properties, researchers warn.
A new study from Lund University in Sweden has found that permanent hair dyes, also called oxidative dyes, are the ones most dangerous to both its users and those who apply these on them.
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For their study, the researchers looked at o-toluidine levels in the blood, along with levels of seven other potentially carcinogenic aromatic amines; o-toluidine (ortho-toluidine) has actually been confirmed as a carcinogenic.
Researchers measured its levels in the blood of 295 female hairdressers, 32 regular hair dye users and 60 people who had not used any of these products.
They found that hairdressers were indeed exposing themselves to o-toluidine and meta-toluidine (m-toluidine) and were at risk.
A similar trend was seen for perming treatments in respect of o-toluidine levels.
"The ingredients of hair dyes and perming products should be analysed to find out if these products continue to be potential sources of toluidine exposure," researchers said.c