Chemicals in Hair Dye
Many people are not aware that there are often harmful chemicals in hair dye. Millions of people – both men and women – change the color of their hair on a regular basis, either at home, using hair-color products off the shelves, or at a salon, using the services of a trained hair-care professional.
And it's nothing new. Would you believe that the very first commercial hair color product was manufactured more than a century-and-a-half ago? The person responsible was a French chemist, Eugene Schuller, who had been experimenting with chemicals, to see how they reacted with the molecules in the hair as well as with pigments and known bleaches like ammonia and hydrogen peroxide. He ended up using the chemical paraphenylenediamine to successful dye hair different colors.
Interestingly, phenylenediamine is still a standard ingredient in modern hair dye products made using chemicals.
To understand how chemical–based hair dye works, you need to understand that hair is made of a protein called keratin, which is exactly the same protein found in our fingernails and our skin. However it is two other proteins – eumelanin and phaeomelanin – that determine the color of our hair. The former produces brown and black hair (and all the hues in between), and the latter, blonds, red, ginger, and all those similar yellow-red colors. If neither protein is present, hair will be grey or white.
Using chemical hair dye to color the hair relies on a complex reaction between the chemicals in the hair-colouring product and the various chemicals and biochemicals that exist naturally in the hair. Using bleach to remove natural hair color relies on another type chemical reaction, as the bleach reacts with the melanin in the hair, oxidizing the melanin molecules, making them completely colorless.
Unless steps are taken to make the hair completely white and featureless, bleaching agents will usually turn hair a pale yellow-blond. Another factor is that the dark eumelanin pigment reacts more effectively with bleach that with phaeomelanin. This is important when deciding what color to dye your hair.
The chemicals found in different brands of hair dye are similar, but not exactly the same. Those that are intended to bleach and then dye hair blond do all contain alkaline hydrogen peroxide (very strong, effective bleach) in the developer that you mix with the color. Generally chemicals that hair dyes also contain include ammonia (which is a gas with a distinctively strong, rather unpleasant odor) and resorcinol (a particularly harsh chemical that can irritate the skin). The colorant usually contains phenylenediamine.
The chemicals used in hair dye formulas have a variety of different functions. For instance they prepare the hair so that the dye will be effective, altering the shaft of the hair. But chemicals are also used to minimize damage to the shaft. If the dye is considered "permanent" (meaning it will have to grow out of the hair and cannot be simply washed out over time), chemicals are added to the formulas to ensure that the color change is permanent.
Of course there is always a risk factor if chemicals are added to products we use. Generally these will be listed on the packaging and you should be aware of what the possibilities are – even if you are never affected in any way. For instance an allergic reaction could cause skin discoloration (if your skin is "white" it might become pink, or even quite red). It might also result in a rash or even cause parts of your face to swell.
Phenylenediamine is known to cause serious skin problems, eye irritations, asthma, gastritis and sometimes even worse conditions. So if you have any side effects at all, stop using the product and visit a doctor for a check-up.