Document J3NgK5w1kJ6MGNJDDbpEZnMX2

fiNERAL C' 4UKD eh:':! VINYL CHLORIDE TOXICITY New York Office Mr. F. C. Kitchings Manager, Ganetrons Gen.Chem.Res.Lab. W. A. Knapp March 26, 1962 1. As you know, toxicological work on this compound was done at Yale University and report submitted in February, 1960, concluded that present threshold limit value of 500 ppm appeared to give an adequate margin of safety. Since this time Torkelson, et al of Dow Chemical Co., (Am.Ind.Hyg., Assoc.,J. , 22, 394-398 (I960)), ha/e published an article recommending a threshold limit yalue of 100 ppm with a time-weighted average for all exposures not to exceed 50 ppm. .2 Our toxicologist at Yale, Dr. Lester, has now received a latter from Dr. H. B. Likins, Massachusetts control official and member of ths ''Threshold Limit Value" committee of ACGlll stating that he Is proposing a value of 50 ppm based on Dow date and requesting tle:t Dr. Lester submit any data he has to refute this value. Dr. Likins' knowledge oC the Yale wo: through Dr. Keith Jacobson of Chemical Warfare Service to whom Dr. Lest er had viri tine on the hey -17, 1942 program of L* A. 1. w Indu strial VV.rror-?-- cue Assaciat ion, to v> 1C din an t 4 a * J 3. Dr. Lester has not complete d wri f- - --j /% of1 hi: ap ar lor meet in a but: has gr ranisod Dr . r.lk .\ *i'*> kf(: a c '>py w r t. i in 3-4 weak s 0 r i sumniary of 1" ic`: cut data within about one week. 4. A copy of Dr. Alins'letter to Dr. Lestev will be distributed to recipients of this letter as soon as received. 0rlSin:ii si*nep A- Knapp Research Consultant WAD: dak cc: Mr. W. G. Ooo 1 ay, >upv. , Org. ?rouuc c s Ted: .jerv.,Uoivay rocess Div., Mr W. A. Marshall, Mgr. ,urg.CLem. Dales, Golvay Process Div. AS I 000015765