London: British scientists have warned hair dyes contain chemicals that could cause cancer among the consumers.
Millions of women and men across the globe use different chemicals to colour their hairs.
The scientists from Leeds-based company Green Chemicals said that every hair dyes contains secondary amines which react with tobacco smoke and exhaust fumes to create extremely hazardous chemicals called N-nitrosamine.
They say that both home hair colouring kits and the dyes used at expensive hair salons pose a potential risk to health.
The researchers urged it is imperative that the risk to health should be quantified because more than a third of women and one in ten men regularly using the hair dyes.
Previously, many doctors linked the hair dye for several disease life threatening diseases including breast tumours, bladder and leukaemia.
One of the authors of the study, Professor David Lewis said: ‘At this stage, we can’t be sure of the amount of N-nitrosamines produced or the level of risk these compounds pose but it is clear a potential hazard exists.
However, the cosmetics industry has strongly disputed the claim and also insisted that the possibility of the chemical reaction has been long known.
In 2009, a source revealed that women who use hair dyes more than nine times a year have a 60 per cent greater risk of blood cancer. A year later the European Commission banned 22 hair dyes which put long term users at risk of bladder cancer.