To the Editor:—
The terms, 2,4-dichlorophenol and 2,4,5-trichlorophenol, are the commonly accepted designations for the phenoxy acetic acids of these compounds. It makes no difference if the basic compound is acidified or esterified, or synthesized into a salt. The point is that the benzene ring with two or three chlorine atoms attached is involved in the etiology of chloracne and/or symptomatic porphyria cutanea tarda (PCT).These herbicides are indeed useful. We simply pointed out that, at least in their synthesis, toxic side effects are to be looked for.We have had a report, documented with photographs, of chloracne occurring in an agricultural area where the finished phenoxy compound is being used. This was not stressed in the communication, since we were concerned with the occurrence of PCT and chloracne in the manufacture of herbicides.