Toxic Chemicals in Common Hair Dyes Linked to a Variety of Cancers
Chemicals in common hair dyes used by millions of women can increase the risk of cancer, scientists have warned.
The latest review of the chemical make-up of common hair dyes, published in the journal Materials, revealed that ingredients in a range of dyes used in home hair coloring kits and at salons pose a significant potential health risk to people who use them.
British scientists from the Leeds-based company Green Chemicals PLC found that the chemicals in permanent hair dyes can react with tobacco smoke and other common air pollutants to form one of the most carcinogenic compounds known to man.
Researchers say that with more than a third of women and a tenth of men regularly coloring their hair, it is "imperative" that the risk of health posed by hair dyes is thoroughly evaluated.
Researchers said that all the information they used in the review was already available and that the study merely "joined the dots" to link hair dye to cancer.
Researchers said that oxidative hairs dyes, which are commonly used in both home kits and in professional salons, contain chemicals called secondary amines, which can penetrate the skin can stay on hair for months or even years after the dye is applied.
The team of researchers said that over time, secondary amines could react with common air pollutants like tobacco smoke and exhaust fumes to form cancer-causing chemicals called N- nitrosamines.
While N- nitrosamines have already been banned for use in cosmetics in the US and in the UK, researchers argue that these toxic chemicals can still be generated via a simple chemical reaction.
"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," researcher Professor David Lewis said, according to the Daily Mail.
"In the interest of consumer safety, it is imperative that a thorough and independent investigation is conducted to establish the levels of toxicity of these compounds and the potential risks," Lewis added.
This is not the first time hair dye has been linked to cancer tumors. Past studies have also linked hair dye to breast cancer, bladder cancer, ovary cancer, brain cancer and leukemia. In 2009, researchers found that women who colored their hair more than nine times a year had a 60 percent greater chance of developing blood cancer.