They create permanent dyes that do not cause allergy
Cosmetic products are source of allergies and one of the most problematic are permanent hair dyes.
In recent years, there has been an increase in cases of allergic dermatitis caused by paraphenylendiamine (PPD), a habitual chemist in this type of.
Now, a team of researchers has discovered how to reduce the allergic effect of this substance to develop equally permanent but less harmful dyes.
The dyes penetrate the skin
Paraphenyndiamine is an aromatic amine that was synthesized in Germany in 1883.The objective was to achieve a substance with antioxidant and staining properties.
It is used in rubber, print ink, photographic products, footwear, lacquers, eye shadows or tattoos of Henna, but one of the most common uses are permanent hair dyes.
When applied as a hair dye, it suffers a chemical reaction that darkens hair color and does not disappear over time.That is why they are very effective products to cover gray hair.
It should be remembered that allergies do not arise from one day to another, you can have been using a dye for years until, suddenly, it begins to cause discomfort.
Risk of allergic dermatitis
As we said, when paraphenylamine is applied in the shape of a hair dye, there is a chemical reaction that darkens it.
But this reaction can also produce compounds that bind to skin proteins causing allergic responses.
Cutaneous symptoms may appear between 24 and 72 hours after applying the dye in previously sensitized people;or between 4 and 14 days later in those that are exposed for the first time.
How to take care of skin with atopic dermatitis
In hairdressing professionals who work daily with these products, the allergy to paraphenilendiamine is presented in the form of chronic hand eczema.
Paraphenyndiamine can also increase sensitization to other chemicals found in sun and cosmetics protectors.
Whether the allergy is serious as if it is milder, the product must be avoided.
However, when the inconvenience is not very intense, many people continue.
That is why dermatologists insist that it is necessary to raise awareness of the population of the potential risk of allergy that permanent dyes have.
And also of the need to modify the composition of capillary dyes so that they do not give so many problems.
Effective but safe alternatives
Until now, the alternatives proposed to paraphenilendiamine were not water soluble and their safety was not well proven.
A team of researchers led by Gopalakrishnan Venkatesan, from the University of Singapore, has been investigating options to avoid the problems of this chemist and in turn will provide a permanent hair coloring.
Chemists also alter your hormonal system
Five of the modified dyes were "weak" sensitizers, while the PPD was "moderate".
Another test showed that new compounds generated a reduced inflammatory response in skin cells compared to the PPD.
"These results suggest that new dyes can dye hair effectively and at the same time avoid possible allergenic and sensitization risks compared to traditional ones," the study authors point out.
Now it only remains for the cosmetic industry to take note.