Document e0MYyzx712Z9476nqJogKwe

DIVISION OF FISH AND GAME LESTER G. MACNAMARA DIRECTOR DEPARTMENT OF CONSERVATION AND ECONOMIC DEVELOPMENT ROBERT A. ROE, COMMISSIONER PLEASE REPLY TO p. O. BOX 1809 TRENTON, N. J. STATE QF NEW JERSEY BUREAU OF FISHERIES LABORATORY. LEBANON, NEW JERSEY. 08833 May 29, 1969 Mr. Tom C. Ford, Manager Division Public Relatinns Monsanto Corporation 800 N. Lindbergh Blvd. St. Louis, Missouri 63166 Dear Mr. Ford: If possible I would appreciate a copy of Monsanto's March- 3, 1969 Statement on PCB (Poly chlorinated phenol) which; I understand you previously sent to Mr. Jim Staples of the Newark News on May 7th. Also, any additional in formation on this material, especially with regard to its use and effects upon the environment would be helpful. Very truly yours, C''^r /0U,C^X A. Bruce Pyle Ass't. Bureau Chief ecs r \ DSW 203175 \ i STLCOPCB4053089 PRESENT STATE OF POLYCHLORINATED BIPHENYL RESIDUE ANALYSIS _I "- When extracts of environmental samples are examined by electron capture gas chromatography, peaks corresponding to widely disseminated chlorinated hydrocarbon (CHC) pesticides and their metabolites and break down products appear on the resultant chromatograms. In addition to these peaks pesticide researchers have been aware for"some time that it was not unusual for an additional series of as many as 10 to 20 peaks, corresponding to unidentified compounds, to also appear on these chromatograms. Little is known of the structure and origin of these compounds except that they / possessed electron capture gas chromatographic properties ' similar to the CHC pesticides. In about 1965, it was established that these ' unidentified materials were organochlorine in nature, with substantial chlorine content and consequently possessed ' ' '. electron-capturing properties. \ , Early in 1967, Swedish researchers at the University of Stockholm (Jensen and Widmark) announced that they had succeeded in identifying a series of such peaks as higher chlorinated biphenyls using gas chromatographic/mass spectrometric techniques. " ________ _ -more- dsw 203176 STLCOPCB4053090 --2 POLYCHLORINATED BIPHENYL RESIDUE ANALYSIS xxx techniques. Based on Jensen and Widmark's unpublished mass ' spectrometrie identification of some similar unknown 'contaminants in a relatively small number of Swedish fish and bird extracts, some researchers in the United States and other parts of Europe precipitously began to report unidentified organochlorine materials as polychlorinated biphenyls with no supporting data other than relative retention times from electron capture gas chromatograms. This would seem to indicate , in view of the well-known limitations of electron capture gas chromatographic analysis, that it would be scientifically prudent to continue the established practice of reporting these materials as organochlorine contaminants when positive structural confirmstion- techniques such as.mass spectrometry are not employed. This Is especially true when one considers that any number of technical grade chlorinated materials (toxaphene, chlordane, chlorinated naphthalenes, etc.) produce electron capture gas chromatographic peaks with retention times corresponding to those produced by commercial PCB. more 0SVM STLCOPCB4053091 ) --3 POLYCHLORINATED BIPHENYL RESIDUE ANALYSIS xxx.PCB. j. . - i Furthermore, the response of an electron capture detector to closely related isomers can vary considerably. Theoretically, there are 210 possible PCB isomers. So it should be clearly stated, at this point in time, that PCB residue:analysis using only electron capture gas chromatography is neither positive nor quantitative. . In attempts to make the less sophisticated and more readily accessible technique of electron capture gas chromatography more selective (positive), several laboratories have introduced prior chemical treatments (saponification, extraction with sulfuric acid, nitration, etc.). Unfortunately the use of the nitration procedure has caused considerable confusion. This treatment is essentially that used to remove DDT and its metabolites from toxaphene. In our laboratories we have found that this treatment results in the disappearance of the early eluding possible PCB isomer peaks in the production of peaks with longer retention times (nitrochlorobiphenyls). Additionally, the treatment is not easily reproduced nor specific for PCB. -more- \ STLCOPCB4053092 ) --4 POLYCHLORINATED BIPHENYL RESIDUE ANALYSIS xxx PCB. Is is apparent that our primary concern at this time should be to develop more specific and systematic analytical procedures which will allow us to accumulate . |. enough unequivocal data to permit the ecologist to conscientiously assess the situation. -0O0- DSVV203179 STLCOPCB4053093