TY - CHAP M1 - Book, Section TI - Contact Dermatitis (Type 4 Sensitive Skin) A1 - Goldenberg, Alina A1 - Jacob, Sharon E. A2 - Baumann, Leslie S. A2 - Rieder, Evan A. A2 - Sun, Mary D. Y1 - 2022 N1 - T2 - Baumann’s Cosmetic Dermatology, 3e AB - SUMMARY POINTSWhat’s ImportantContact dermatitis, including irritant and allergic variants, affects up to 20% of the population at some point in their life. Personal hygiene and cosmetic products are the culprits behind the majority of the non-occupational cases of contact dermatitis involving the face, neck and hands.Allergic Contact Dermatitis (ACD) can develop to a chemical ingredient in a product that has been in routine use for years. The cutaneous response of ACD, with erythema, scale and pruritus, can extend beyond the area of direct contact with the allergen.Fragrances and preservatives are common agents causing ACD. Package labeling of “fragrance free” may mislead the consumer, if the manufacturer includes the fragrance-based ingredient for a non-fragrance function, eg: as a preservative.Essential oils are the building blocks of fragrances. Natural is not synonymous with safe.What’s NewMethylisothiozolinone (MI) overtook formaldehyde-releasing preservatives and fragrances as the leading prevalent sensitizing allergen. Moreover, MI was found to be the most clinically relevant allergen, with the highest ever recorded relevance value.Dillarstone effect describes the development of new contact dermatitis epidemics following 2–3 years after introduction of an allergenic compound to the market.Although cautioned by the media, parabens are consistently found to be weak sensitizers and play a very minor role in ACD. Moreover, epidemiologic data has failed to show a direct connection between parabens and hormonal effects or the development of breast cancer.What’s ComingThe COVID-19 pandemic dampened, but saw a rise in index cases of ACD associated with personal protective equipment (masks, gloves and hand sanitizers) both in the health care industry and the public realm.Open dialogue between consumers and industry members on social media has sparked a movement toward more “clean,” ethically transparent, allergen-free cosmetics which may be the focus of the next decade. SN - PB - McGraw Hill LLC CY - New York, NY Y2 - 2024/03/28 UR - dermatology.mhmedical.com/content.aspx?aid=1197533873 ER -