Document a4N4yyzRz38XDJ15m9XL68aXe

Roman - N3B Monsanto 1^ 1- M ONSANTO INDUSTRIAL CHEM ICALS CO BOO N Lindbergh Boulevard Si, L o u i s . M i j o u m 631 6 6 P h o n e : (3141 6 S 4 - 1 0 0 0 September 3, 1981 Dr. C. E. Mendoza Task Force for Reassessment of Chemical Safety Dept, of Health and Welfare Health Protection Branch Ottawa, Ontario Canada K1A0L2 Dear Dr. Mendoza : Santophen$-l (Monsanto o-benzyl-p-chlorophenol) has been analyzed for 2,3,7,8-tetrachlorodibenzodioxin by an analytical method capable of detecting 0.5xl0-9 gm TCDD/gm Santophen-1; none has been detected. Approximately twenty lots of material produced in 1979 and 1980 were examined. The analytical method used liquid chromatographic separation with U.V. detection, and was essentially similar to that described by Nestrick, ^.aj^. , (Anal. Chem., 1979, 3_1, 2272). This method is capable of conclusively indicating the abTence of 2,3,7,8TCDD (above the detection limit) but it does not resolve this compound from seven isomers. No lot of Santophen-1 produced by Monsanto's current manufacturing process examined to date has shown evidence for the presence of 2,3,7,8-tetrachlorodibenzodioxin. Very truly yours, JDW/bh CC**-Mr . Kith Rar.Ml \Ia 100 Argyle Ave. .Octnwa, Ontario me s D. Wilson /Manager, Research i Development