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Brilliant Lake Red R as a cause of pigmented contact dermatitis
Author(s) -
Kozuka Takehito,
Tasihro Minoru,
Sano Shigeharu,
Fujimoto Keiichi,
Nakamura Yumi,
Hashimoto Seiichi,
Nakaminami Gen
Publication year - 1979
Publication title -
contact dermatitis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.524
H-Index - 96
eISSN - 1600-0536
pISSN - 0105-1873
DOI - 10.1111/j.1600-0536.1979.tb04882.x
Subject(s) - azobenzene , chemistry , cosmetics , ethyl acetate , contact dermatitis , chromatography , impurity , thin layer chromatography , nuclear chemistry , organic chemistry , allergy , medicine , molecule , immunology
Twenty‐three patients suffering from pigmented contact dermatitis caused by cosmetics containing Brilliant Lake Red R were observed. Commercial samples of Brilliant Lake Red R proved to contain many ethyl acetate extractable impurities; 1‐phenylazo‐2‐naphthol and azobenzene were isolated and identified. To determine the responsible allergens, five patients were examined by patch tests with purified samples of azo‐dyes and the unidentified fractions of ethyl acetate extractable impurities. Three out of five showed weaker reactions to purified samples of Brilliant Lake Red R and the other two showed equal reactions compared to the commercial product. 1‐Phenylazo‐2‐naphthol was found to be a strong allergen in all cases but none showed a positive reaction to azobenzene. Some unidentified fractions also gave positive results. Patch tests were performed with 4‐phenylazo‐1‐naphthol, 4‐phenylazo‐1‐naphthol‐2‐carboxylic acid, and 2,4‐bis(phenylazo)‐1‐naphthol, as structurally related compounds derived from 1‐naphthol. All gave negative and they were not detected in the ethyl acetate extractable impurities by thin‐layer chromatography.