To the Editor:—
The problem discussed in "Occupational Acne" (Questions and Answers, JAMA188:336 [April 20] 1964) is a difficult one, since at least some of the possible causes of chloracne listed are quite new chemicals. We now have more than 40 cases of chloracne in workers engaged in the synthesis of 2,4-dichlorophenol and 2,4,5-trichlorophenol, both extensively used as weed killers. A study of this group (Arch Derm [Chicago] 89:793 [June] 1964) points out the coexistence of chloracne and porphyria cutanea tarda in some of these workers.To rule out the possibility that an intermediary chemical caused the chloracne, Dr. Marcus Key of the Industrial Disease Division of the US Public Health Service performed open patch tests on himself with the finished products. He successfully induced typical chloracne on his arm.As Dr. Peck correctly pointed out, impeccable personal hygiene is essential for people working with these compounds.