The process, which involves sealing liquid keratin into the hair using a straightening iron, is popular as a way of keeping hair straight for long periods of time, usually between 3 and 5 months.
However, the process has also been shown to release unsafe levels of highly toxic formaldehyde, sometimes more than 50 times the regulated limit, reported IOL . Including more formaldehyde in the chemicals used makes the treatment more effective and longer lasting but it also increases the user’s chance of developing several cancers.
Read: Hair extensions could lead to permanent hair loss
The US National Cancer Institute supports research linking formaldehyde to leukaemia, lymphoma and throat cancer. The chemical has traditionally been used in embalming and as a fungicide. In the EU products cannot contain more than 0.2% formaldehyde and this has led to the treatment being banned there as well as in Canada.
UCT Professor Nonhlanla Khumalo claims that these products present serious health risks to both those receiving the treatment and those administering it, reports EWN. Hair stylists can spend upwards of 8 hours a day in the presence of harmful chemicals.
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Sources: EWN/IOL/National Cancer Institute