Document x5nGkvYxJ8ea7dp1dbw8XE0mE

OCT t. Ontario Water Resources Water management in Ontario Commission 135 St.ClairAve.W. Toronto 7. Ontario Tel. 365- 248-3031 Division of Laboratories, October 1, 1969. Dr. E. Wheeler, Medical Department, Monsanto Co. Inc., 800 North Lindbergh Blvd., ST. LOUIS, Mo., 63166 USA I was in contact with Mr. M. Jenkins of Monsanto Canada in order to obtain information about polychlorinated biphenyls, PCB. Although he had some general information at hand, he referred me to you for toxicological data. Lately there has been a considerable concern about these materials, chlorinated aromatic compounds, in the natural environment. To date, most of the publicity has been con cerned with DDT group of pesticides. However, there have been reports that the PCB might be equally toxic. It is apparent that the general public is also getting somewhat concerned about these materials. In fact, recently there was a television program about this. From a professional point of view there was not too much solid evidence about the toxicity of PCB. However, there was a strong compari son with the DDT group of pesticides, and equally strong suggestions for further toxicological studies of PCB. It might be of interest to mention in this connection that the Province of Ontario recently banned the major uses of DDT. The possibility that PCB might have a chlorinated pesticide like effect on aquatic biota, is of major concern to the Commission. Since there have been reports that PCB have been found in the natural environment in Ontario (and else where) , it would be of interest to establish the toxicologi cal properties of PCB. It is possible that you already have knowledge about these matters. Any information would be greatly appreciated. DSW 018346 . . .2 STLCOPCB4004890 Dr. eT. Wheeler, Monsanto Co. Inc 2- - October 1, 1969. Finally, I would like to mention that from a personal point of view, being an analytical chemist, the pcb make the life of a pesticide analyst quite miserable. Since they are quite similar to the halogenated pesticides, the analytical results, particularly the gas chromatographic traces, are frequently inconclusive. Any information about this matter would also be greatly appreciated. Yours truly, OWB/jc OSW 01834? STLCOPCB4004891