Potential Hazards of Dinitrochlorobenzene (DNCB) Disputed

To the Editor.—  The March 1985 issue of the Archives contained an editorial entitled "The Potential Hazards of Dinitrochlorobenzene."¹ While some of Dr Happle's opinions are valid, several of his positions are extreme and not supported by facts. I am concerned that the format of the editorial may lead casual readers to believe that his interpretation of carcinogenic risk has wide support. Actually, this is not the case.First, Dr Happle states, "Summer and Göggelmann^[2] showed that DNCB depletes the activity of glutathione S-transferase in rat skin." The cited reference does not support that statement; in fact, it contains the following words, "The topical administration of [DNCB] did not alter significantly the activity of the skin glutathione-S-transferases."²Second, Dr Happle later states, "These arguments are weakened by the fact that the correlation between mutagenicity in the Ames test and carcinogenicity in mammals is up to 90%."¹