To the Editor.—
Maibach et al1 reported in the Archives that thin-layer chromatography (TLC) of urine samples from four of eight subjects, which were taken one to four days after they had dyed their hair with one of two commercially distributed, semipermanent hair dyes, disclosed a purple spot. The spot, which was unidentified, was the same with both dye preparations and was neither detected in control TLC of urine samples from the subjects nor in TLC of either hair dye. The authors concluded that "It is likely that these hair dyes not uncommonly penetrate the skin," and that the purple spot was most likely a metabolite.We found the same purple spot in urine specimens from 13 of 14 subjects who had been treated according to the procedure of Maibach et al, ie, ether extraction of concentrates that were adjusted to pH 1, followed by ether extraction of the
Yare RS, Garcia M. Percutaneous Penetration Following Use of Hair Dyes. Arch Dermatol. 1977;113(11):1610. doi:10.1001/archderm.1977.01640110130028
Coronavirus Resource Center
Customize your JAMA Network experience by selecting one or more topics from the list below.