Cosmetic Allergen in the Past and Present

For almost 20 years after the end of World War II, many Japanese women were challenged by a dark secondary hyper pigmentation on their faces. The causation of this condition was unknown and incurable at the time. However this symptom became curable after a number of new cosmetic allergens were discovered through patch tests and as an aftermath, various cosmetics and soaps that eliminated all these allergens were put into production to be used exclusively for these patients. An international research project conducted by seven countries was set out to find out the new allergens and discover non-allergic cosmetic materials. Due to these efforts, two disastrous cosmetic primary sensitizers were banned and this helped to decrease allergic cosmetic dermatitis. Towards the end of the 20th century, the rate of positives among cosmetic sensitizers decreased to levels of 5% - 8% and have since maintained its rates into the 21th century. Currently, metal ions such as the likes of nickel have been identified as being the most common allergens found in cosmetics and cosmetic instruments. They often produce rosacea-like facial dermatitis and therefore allergen controlled soaps and cosmetics have been proved to be useful in recovering normal skin conditions.

Cosmetic Contact Sensitivity in Patients with Melasma: Results of a Pilot Study

Background. Some of the patients with melasma perhaps have pigmented cosmetic dermatitis. However, cosmetic contact sensitivity in melasma remains poorly studied particularly in the Indian context.Objectives. To study cosmetic contact sensitivity in patients with melasma.Materials and Methods. 67 (F : M = 55 : 12) consecutive patients with melasma between 19 and 49 years of age were patch tested sequentially during January–December, 2012, with Indian Cosmetic and Fragrance Series, Indian Sunscreen Series,p-phenylenediamine, and patient’s own cosmetic products.Results. 52 (78%) patients were in the age group of 20–40 years. The duration of melasma varied from 1 month to 20 years. Centrofacial, malar, and mandibular patterns were observed in 48 (72%), 18 (27%), and 1 (1%) patients, respectively. Indian Cosmetics and Fragrance Series elicited positive reactions in 29 (43.3%) patients. Cetrimide was the most common contact sensitizers eliciting positivity in 15 (52%) patients, followed by gallate mix in 9 (31%) patients and thiomersal in 7 (24%) patients. Only 2 of the 42 patients showed positive reaction from their own cosmetics while the other 5 patients had irritant reaction. Indian Sunscreen Series did not elicit any positive reaction.Conclusion. Cosmetics contact sensitivity appears as an important cause of melasma not associated with pregnancy, lactation, or hormone therapy.