Document 9jYnw8ogNJ66qpKgE98mwEpq

VANDERBILT UNIVERSITY NASHVILLE, TENNESSEE 37232-0146 Telephone 1615) 322-7311 Center in Molecular Toxicology Department of Biochemistry School of Medicine Direct phone 322-2261 FAX 322-3141 July 11, 1990 Dr. Barry Friedlander Director of Medicine and Health Science Monsanto Company 800 N. Lindberg Blvd. St. Louis MO 63167 Dear Barry: I have read these documents in detail and have noted some suggested editorial changes on the manuscripts themselves. Besides the editorial comments I have three additional observations. First, it is my opinion that the elevation in the urinary porphyrins seen in the exposed workers may not have been caused by the chlorinated dioxins. My reason for believing this is that I do not believe that the porphyrin producing enzymes would continue to be induced so long a time after exposure to the levels of dioxins that induced the chloracne. Second, I think the conclusion section of the chloracne chapter could use some additional work. I have indicated on the manuscript the sections which I think should be reconsidered. Finally, I believe the authors should include in their conclusion sections a consideration of the data published on the "Yusho Oil" and "Yucheng" incidences. As you know these were fairly large populations which consumed chlorinated dibenzofuran contaminated rice oil. These are probably the best clinically documented populations exposed to this class of chemicals. In general I think the manuscript is well written. In my opinion, with the few exceptions noted, they have interpreted the results of the study appropriately. I hope these comments will be of some value in your review of this document. Sincerely, Ro! Neal Professor of Biochemistry, Emeritus V / / DSW 476038.0981 STLCOPCB4043142