Document 0JyJNkgB5bmEEDrByarnxk05k

F E L I X E D G A R W O R M S E R , P R E S I D E NT K . C . B R O W N E L L .v i c e p r e s i d e n t %. A - M A R T I N O . VICE PR E SID EN T R O B E R T LINDLEY 2IE G F E L O . SECRETARY-TREASURER 420 LEXINGTON AVENUE NEW YORK 17, N.Y. MANFRED BOWDITCH D IR ECTO R O F H EALTH AN D SAF E TY July 27, 19h9 Robert A. Iiehoe, M. D*, Director Kettering Lab. of Applied Physiology University of Cincinnati College of Medicine Cincinnati 19, Ohio Dear Bob: Xou may be interested in the enclosed com ments by Hervey Elkins relative to the lithopone ^ V, crayon matter on which there has been consider- '"h th : able correspondence. enc. mb/sd KE 00. A' 4u Excerpt from letter, July Iht 19k9 Harvey B. Slkins to Manfred Bowditcfc "As I tola you in New fork, I have not bean able to find, arything in the literature oa the toxicity of lithopona. It occurred to me, however, that it had not been demonstrated that the zinc sulfide la lithopona is decomposed by the gastric juice normally present in the human stomach. Accordingly, I obtained from Carpenter Horton Co. a free sample of lithopona and to 2 grams added 100 ml. of 1/2% hydro- chlorlc acid, According to our physiology text books, this represents the approximate up.or- limit of acid normally present in the gastric juice, vn standing -for approximately 13 hours and aerating at inter- . vaLs, enough ydrogen sulfide was recovered to account for 2,3% of the sine sulfide Uieorsilcolly present* upon increasing the strength of the acid, additional hydrogen sulfide was obtained, until finally using $,y% acid, or approximately ten tines as strong as that presumed bo be present in the stomach, I obtained in about a week something over 30% decomposition of the zinc sulfide. "Tills is only a rough experiment, however, and I certainly would noi use It to predict that lithopona would bo non-toxic, however, I think it siay explain the fact that lithopona is apparently not highly clangorous. According'to some rough calculations, a single crayon worth ing six grams and containing y$% sine sulfide conic produce about, onr,~ third the amount of hydrogen sulfide required to fatally poison an adult. Such an amount would presumably bo rapidly fated to a snail child, how ever, if only 3% of the zinc sulfide wore decomposed in a period of an hour or so, there would not' bo enough hydrogen aulfiue produced to in jur even a very small child, if ny aasumptions as to a fatal dose are correct. "Much as I hat to uo it, therefore, 1 aa inclined to aide with your physician friends, as opposed to my colleague Dr. Fisher, in thair contention that in all probability the dyes rather than the lithopone wore responsible for the case in question." H 001474 r-j f