A recent study published in a scientific journal warns that hair dye is highly carcinogenic, even those used at expensive salons.
The study says that chemicals in permanent hair dyes are poisonous because they can react with tobacco smoke and other pollutants to form powerful cancer-causing compounds.
Researchers say it is “imperative” that the health risk is known as more than a third of women and one in ten men regularly color their hair.
It was conducted by Leeds-based company Green Chemicals, who looked at the chemistry around hair dye. They said it didn’t take much effort, as the information was already available and they simply “connected the dots.”
The main chemicals they are concerned with are called secondary amines. These are found in all permanent hair dyes and can penetrate skin and stay in the hair for years.
They then react with other pollutants in the air to form highly cancerous chemicals called N-nitrosamines. These chemicals are banned in cosmetics as they were already known to be carcinogenic, but researchers say they can still be produced by simple chemical reactions.
Studies have linked hair dye to numerous cancers, including breast, bladder, ovarian, brain and leukemia.
Study author David Lewis said they are unsure of how much nitrosamines are produced by hair dye.
“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. 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,” he said.
Green Chemicals is planning to launch its own “ultra-safe” range of hair dyes, and said that until now, no one had studied the dangers of hair dyes reacting with outside pollutants.
George Hammer of Urban Retreat, the world’s largest hair and beauty salon, said chemical companies were aware of the dangers.
“Chemical companies have a huge vested interest in keeping this under wraps,” he said.
One study in 2009 revealed women who use hair dyes more than nine times a year have a 60 percent greater risk of getting blood cancer.