Use of hair dye chemicals can affect the immune system
Hair dyes are involved in the development of autoimmune diseases and cancer
The first gray hairs indicate our aging and many have only one thought: The gray hairs must disappear. There are many hair dyes on the market, but most contain questionable chemicals to produce their coloring effect. Recently scientists at the University of Copenhagen showed that commercial -p-phenylenediamine (PPD)-contained in the hair dye composition is a potent activator on the immune system. When animal models were in contact with PPD, severe hypersensitivity reactions resulted.
With the discovery of these research scientists, the result leaves only two alternatives to consider: either accept the gray hair, or resort to a harmless lichen hair dye with active ingredients from plants.
Why doesn’t everyone react to the chemicals in hair color products?
With their new study, scientists from Copenhagen wanted to find out why only a minority of the population suffers with hypersensitivity to permanent hair dyes. The scientific research team found that the majority of people are indeed sensitized to hair dyes or the rest of the users develop an immunological tolerance.
Consumer tests simulated situation
To investigate whether an immune response takes place, the researchers exposed mice repeatedly to PPD-containing hair dyes in a manner as it is exposed to the consumer in a similar way. For this purpose, a commercial hair dye that contains PPD, was tested on animals. The local immune response was evaluated by ear swelling and by histological examinations. The immune response in the lymph nodes was analyzed by the researchers using flow cytometry, a still relatively new laboratory technique.
Inflammation and swelling worsened by repeated contact
Hair dye caused local inflammation, which was determined by swelling and cell infiltration of the treated ears. In addition, contact with the hair dye caused T-cell activation, as evidenced by the T-cell proliferation and the production of IFN gamma and IL-17 which was detected in the lymph nodes. The inflammatory reaction was at its peak after the fourth contact with the hair dye.
Effects observed on the immune system
From that point on, the team of scientists observed an up-regulation of regulatory T cells and IL-10 producing cells. The study thus shows that PPD-containing hair dyes strongly influence the immune system. In addition, it became clear that they are potent skin sensitizers that activate the inflammatory T-cells and to induce PPD-containing hair dyes and anti-inflammatory mechanisms. This may explain why many consumers using hair dye can be use the dyes repeatedly without significant development of allergies. Scientists from Denmark, however, believe that one cannot feel entirely safe doing this because facts have been raised concerning the question of whether the influence of the immune modulatory effects of hair dyes are involved in the development of autoimmune diseases and cancer.
Author: Silvia K. Müller, CSN – Chemical Sensitivity Network
Literature:
Rubin IM, Dabelsteen S, Nielsen MM, White IR, Johansen JD, Geisler C, Bonefeld CM., Repeated exposure to hair dye induces regulatory T cells in mice, Department of International Health, Immunology and Microbiology, University of Copenhagen, Denmark, Br J Dermatol., May 13, 2010.