Document K6LvDO3YnjdD2j3Jrz75ReZnw

t PLAINTIFF'S EXHIBIT API-108 April 23, 1953 Professor R. W, Schleaaler Pennsylvania State College School of Chemistry and Physics State College, Pennsylvania Dear Bobj In his letter of April 20 Les Beard probably had In mind the testing of a polycyclic aromatic as a carcinogen whioh requires only a fraction of a mg. of such a solute per application. However, 20 to 100 mg. of total solution, of which the accelerating solvent represents about 99*9 percent, must be applied at eaoh application to each mouse In the tests for which we.are requesting samples. To carry out a biological test of the accelerating potency of a hydrocarbon solvent, it doea require a min- laum of about 2$ grama. Could you lndioate for me which of your samples with 12 to 2$ carbon atoms are currently avail able in this quantity? Since a complete mouse test on such materials requires several months of work and a not in appreciable nlok In our project budget, X oan assure you that we shall not swamp you with requests for large numbers of samples of the-25 g* size. Ife should, however, like to select two or three of the list which would provide the most pertinent Information, complete the tests on them, and than review the situation to see just where additional hydrocarbon types or molecular weights are then needed to round out the picture, ^, There are preliminary Indications that there is some relation between the surface activity of hydrocarbons such as deoylbenzene and their physiologic action in car cinogenesis Have you made any measurements of the surface tension, spreading coefficients, or other Indications of surface activity of your collection of hydrocarbon samples. If we oan oarry this correlation far enough, we may eventually be able to estimate the accelerating potency of samples of * SC-API-2411 Dr. B. W. Schiessler April 23, 1953 relatively small size simply on the basis of their surface activity as measured perhaps, by their spreading coefficients on water or triglycerides. Sincerely yours. AWHmjg CCi Dr. I. C. Beard, Jr. Dr. R. C. Mlthoff Dr. L. M. Henderson Dr. J. H. Raaser Dr. R. P. Marsehner A. Wesley Horton r S OCO N Y - VACUUM LABORATORIES DIVISION OF SOCONY-VACUUM OIL CO., INC. W. M. HOL.ADAY director T. W. NELSON ASSOCIATE DIRECTOR L. C. BEARD. JR. J. C. ZIMMER ASST. DIRECTORS 26 Broadway, New York 4, N.Y. * ESEAICH AND DEVELOPMENT DEPAKTNENT FAULSSOAO. H. J. TECHNICAL SERVICE DEPARTMENT aooklvn. h, r. MA6N0LIA FIELD RESEARCH LAlOftATORIE* DALLAS. TEXAS Dr. Harry Sutherland Shell Oil Company Agricultural Laboratory Box 1531 Modesto, California April 20, 1953 API Project 42 Samples to Kettering Jor Carcinogenicity Studies Dear Harry: In reply to your letter of April 16, 1953, please be advised that 1 concur in loaning Dr. Vasaund of Sinclair samples of the nine hydro carbons which he requested. With reference to the last paragraph of your letter; X would like to urge that APX Project 42 cooperate in every way reasonable with the APX work on carcinogenicity at Kettering Laboratories in Cincinnati. Wes Horton, under whose direction this carcinogenicity work is being done, has found that esrtain hydrocarbons,in themselves non-carcino- genic, intensify the carcinogenic properties of typical 4 and 5 conju gated ring carcinogens. Wes at one time had contemplated a synthesis program at Kettering. I counselled against this as it could constitute duplication of API work. X think Wes has come up with a new and important slant in this co-carcinogenic effect. Bob Mlthoff of California Research is Also a member of the Advisory Committee on Carcinogenicity, and by copy of this letter X am suggesting that he express his opinion in this matter to George Denison, and George can then let you know regarding Bob's feelings. I do believe that Wes is rather optimistic as to the amounts of_hydro- carbons that APX Project 42 have on hand, and by copy of this letter to him 1 mm urging that he moderate his request as concerns amount to the very minimum. X cannot see how he will require 25 grams since these hydrocarbons will be used for biological teats in which they are painted on mice to the extent of several applications per wesk and only a few milligrams per application. ' Very truly yours, XaCBlEXL cc: Messrs. 1. M. Barber ' J. X. Bates G. H. Denison L. C. 3KABD JB. vS X. Bendercon L. A. KikesJta A.Wesley Horton B. C. Mlthoff CtJL B. F. Marschner^ J. H. Xamser 1. W. fichieesler