Color additives adverse reactions

Colorings as Additives Associated with Adverse Reactions... 

Skin Temporary henna tattoos have become increasingly popular. The active dyestuff in henna is 2-hydroxy-1,4-naphthoquinone (Lawsone). Contact allergy and immediate hypersensitivity reactions to heima are rare events, as traditionally heima is used as a pure dye prepared from the stems and the leaves of the plant, with the addition of coffee or tea for enhancing the color. The growing practice of mixing in various chemical dyes, such as para-phenylenediamine (PPD a chemical sensitizer), to enhance the properties of henna has resulted in an increase in the number of adverse allergic reactions caused by these tattoos. 

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