Why would a powder lightener make the hair hot to touch?

Hi,

We had a client in our salon that wanted foils and wanted to go lighter, our client has previously used home colours and stopped colouring to go lighter. We used powder lighter and 20% and her hair started to go really really hot to touch so we washed it off straight away but we don’t know why this would have happened. The colour she used "Garnier" has no metallic salt in them.

We’re so confused, please HELP!!!

Charlotte, New Zealand

Powder lighteners all generate some heat when they are wrapped in foils, but if they are really hot to the touch then I am not sure what might be on the hair to cause this. Garnier home colours don't contain metallic salts and are quite alright to colour over with professional products. I do think you should ask her whether she is a swimmer or if she is on medication, these both can affect hair colouring. 

Ask her to come in and do a strand test (mix equal parts perm lotion and peroxide and put a strand of her hair into the mix). If the hair gets hot, bubbles or breaks then you know she has got some sort of metallic salt build up on the hair shaft.

John Clark at Brooks+Brooks, London