Publicação
Evaluation of hair dyes influence on the epidermal barrier using an in vitro test
| Resumo: | The human being has the intrinsic desire to improve his appearance. Therefore, hair dyes have become a very popular product, which knows no gender or age barriers. According to statistics, more than 70% of women in developed world admit dyeing their hair at least once in their lifetime and most do so on a regular basis. Due to the extensive use of this type of products and their high chemical complexity, safety and legislation are very important aspects to ensure high standards of safety to consumers. Many users of these cosmetic products are not aware of the short-term and long-term effects they may cause. It is therefore important to study the influence these products can have on the skin, especially in the sensitization or irritation of the skin. This study aimed to study the influence of hair dyes on the epidermal barrier of the skin. The evaluation was performed indirectly using an in vitro model. Changes in the epidermal barrier were monitored through the measurement of TEWL, which is considered a criterion for the evaluation of skin barrier function. The first tests were performed using two controls: water as a negative control and a 20% SDS solution as a positive control. Subsequently, 10 different combinations were tested to evaluate the changes they can produced in the TEWL values, after their application, in relation to the basal values. It can be concluded that all the cosmetic products tested have a deleterious effect on the epidermal barrier of the skin, since all produced an increase in TEWL values. According to the results, there also appear to be no significant differences between the two brands tested and the effects produced on the epidermal barrier. Through this work, it was not possible to confirm the of involvement H2O2 in skin barrier disturbance, nor to relate the percentage and amount of H2O2 present in the formulation and the magnitude of the effects produced. The tests performed were considered insufficient to ascertain the relationship between the compounds tested and the effects produced on the skin, also not allowing elicit associations regarding a particular compound. On the other hand, the tests were performed using pig ear skin, which does not allow extrapolating results obtained for human skin. |
|---|---|
| Autores principais: | Brito, Joana Rita Fernandes Castilho de |
| Assunto: | Skin sensitization Hair dyes Transepidermal water loss Franz cells Mestrado Integrado - 2017 |
| Ano: | 2017 |
| País: | Portugal |
| Tipo de documento: | dissertação de mestrado |
| Tipo de acesso: | acesso aberto |
| Instituição associada: | Universidade de Lisboa |
| Idioma: | inglês |
| Origem: | Repositório da Universidade de Lisboa |
| Resumo: | The human being has the intrinsic desire to improve his appearance. Therefore, hair dyes have become a very popular product, which knows no gender or age barriers. According to statistics, more than 70% of women in developed world admit dyeing their hair at least once in their lifetime and most do so on a regular basis. Due to the extensive use of this type of products and their high chemical complexity, safety and legislation are very important aspects to ensure high standards of safety to consumers. Many users of these cosmetic products are not aware of the short-term and long-term effects they may cause. It is therefore important to study the influence these products can have on the skin, especially in the sensitization or irritation of the skin. This study aimed to study the influence of hair dyes on the epidermal barrier of the skin. The evaluation was performed indirectly using an in vitro model. Changes in the epidermal barrier were monitored through the measurement of TEWL, which is considered a criterion for the evaluation of skin barrier function. The first tests were performed using two controls: water as a negative control and a 20% SDS solution as a positive control. Subsequently, 10 different combinations were tested to evaluate the changes they can produced in the TEWL values, after their application, in relation to the basal values. It can be concluded that all the cosmetic products tested have a deleterious effect on the epidermal barrier of the skin, since all produced an increase in TEWL values. According to the results, there also appear to be no significant differences between the two brands tested and the effects produced on the epidermal barrier. Through this work, it was not possible to confirm the of involvement H2O2 in skin barrier disturbance, nor to relate the percentage and amount of H2O2 present in the formulation and the magnitude of the effects produced. The tests performed were considered insufficient to ascertain the relationship between the compounds tested and the effects produced on the skin, also not allowing elicit associations regarding a particular compound. On the other hand, the tests were performed using pig ear skin, which does not allow extrapolating results obtained for human skin. |
|---|