Analytical Methodology for Herbicide Orange. Volume II - Special ...

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SECTION IINTRODUCTIONCommercial herbicide formulations containing 2,4,5-T (2,4,5-trichlorophenoxyaceticacid) have been used extensively over a period of years forbrush control in the United States, and were applied for defoliation purposesin South Vietnam.^"6 in 1970 it was discovered that some herbicide formulationscontaining 2,4,5-T also contain prohibitive levels (several parts-permillion)of a highly toxic contaminant, TCDD (tetrachlorodibenzo-p-dioxin), 2 " 6TCDD is formed as a by-product in the manufacture o*: 2,4,5-T and is approximatelya million times more toxic than 2,4,5-T. 1 ' 7 TCDD is known to causechloracne and other skin diseases in humans,8-11 endema in new-bornchicks,•'•O>12,13 ancj numerous birth defects in rats, mice, and hamsters. 1^-17In addition, the effects of TCDD may be cumulative.^ By 1970, the hazardsof the TCDD present in 2,4,5-T were well l:nown, and as a result further useof herbicides containing this compound was suspended in South Vietnam. Theuse of 2,4,5-T in the United States was also restricted. The U. S. EnvironmentalProtection Agency placed a total ban on the usa of 2,4,5-T having a"high"dioxin content. The level of TCDD which can be tolerated safely inherbicides is a subject of much controversy, and these limits may be revisedin the near future.The herbicide formulation used in South Vietnam was designated HerbicideOrange and consisted of an approximately 50-50 mixture of the butyl estersof 2,4-D (2,4-dichlorophenoxyacet.ic acid) and 2,4,5-T. When use of thisherbicide in Vietnam was discontinued, large quantities of this material wereon hand,and these remain in the USAF inventory today. Some 2.3 milliongallons of this material are presently stored in 55-gallon drums in twolocations—Gulfport, Mississippi, and Johnston Island in the Pacific Ocean.It is desirable to dispose of this herbicide as soon as practical,by either destroying it or (for those lots containing a "safe" level ofdioxin) using it for brush-killing applications. Either procedure requiresEPA approval or certification, and this, in turn, necessitates data on thechemical couposition and homogeneity of the herbicide on hand.The 15,200 barrels of herbicide presently stored in Gulfport, Miss.,were originally purchased in ten lots from several different manufacturers.Unfortunately, owing to rebarreling and handling of much of the herbicide,some mislabeling has occurred. As a result, extant records may or may notbe useful for assigning a given barrel of Herbicide Orange to one of the tenlots which were originally purchased. It is desirable, therefore, to developa simple and reliable technique for characterizing the Herbicide stocks on alarge-volume basis. The goal of the present work was to determine whether arapid, routine analytical technique such as gas chromatography could beapplied a) to characterize groups within the Herbicide-Orange stocksaccording to manufacturer or manufacturer's production run and b) to demonstratethat such groups are homogeneous, that is, that a given manufacturer'sproduct consistently has the same composition. Achieving these goals wouldgreatly reduce the number of analyses required to characterize the entireinventory since, hopefully, it would reduce a barrel-by-barrel analysisproblem to a gtoup analysis problem.
Reported herein are results of analyses of a limited number of barrelsof Herbicide Orange. The volatile components of the samples of herbicidewere analyzed by temperature-programmed gas chromatography.20 All c'lromatographicpeaks were not resolved. Greater effort could have bp.en made toresolve overlapping peaks through more careful selection of -2 liquid phase,^1porv-injector splitting of the carrier flow and multiple columns in series,22programmed-pressure gas chromatography,^3 trapping ard relnjecting,^ backflushing,25 or complex valving arrangements of multiple columns in series.26-28These techniques, while useful in analyzing mixtures with components of widelydiffering boiling points and physical-chemical properties, increase the timeof analysis or the complexity of the analytical apparatus—both undesirablewhen a barrel-by-barrel determination is being performed. As will be shown,the simple gas-chromatographic analysis performed proved to be quite sufficientto identify homogeneous groups of the Herbicide-Orange stock accordingto manufacturer or manufacturer's production run. The data presented demonstratethe feasibility of identifying Herbicide Orange by its characteristicgas-chromatographic "fingerprint."
Page 1 and 2: Item I Number 04848 D NotScann8dAut
Page 4 and 5: A D - A 011 5 y 8ANALYTICAL METHODO
Page 7 and 8: UnclassifiedSECURITY CLASSIFICATION
Page 9 and 10: PREFACEThe research and development
Page 11 and 12: LIST OF TABLESTABLEPAGEIIIIIIIVVVIV
Page 16 and 17: SECTION IIEXPERIMENTALSAMPLING PROC
Page 18 and 19: TABLE IIDENTIFICATION DATA ON HERBI
Page 20: 59 Hercutes 14I900 1800 2700TIME, S
Page 23 and 24: m—is900t1800 2700TME.SecFigure 5.
Page 25 and 26: 251 Dow 10s900 1800 2700TIME.SecFig
Page 27 and 28: o CL OO900 1800TIME, SecFigure 9.Ch
Page 29 and 30: 263 MONSANTO 6BOO27QOTOE.SECFigure
Page 31 and 32: TABLE IIICOMPARISON OF ANALYSES OF
Page 33 and 34: TABLE VCOMPARISON OF DUPLICATE SAMP
Page 35 and 36: TABLE VIICOMPARISON OF DUPLICATE SA
Page 37 and 38: TABLE VIIISUMMARY OF ANALYSES OF HE
Page 39 and 40: TABLE VIII (Continued)RetentionTime
Page 41 and 42: 11) Analysis Sequence Group 6 (Mons
Page 43: 19. R. Baughman and M. Meselson, Ad

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