EPA Method 8081A Organochlorine Pesticides by Gas Chromatography - Revision 1

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F667A63A8A0D47B2AF18D3A0DAB74BB3

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2003-1-16

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CD-ROM 8081A - 1 Revision 1,December 1996,METHOD 8081A,ORGANOCHLORINE PESTICIDES BY GAS CHROMATOGRAPHY,1.0 SCOPE AND APPLICATION,1.1 Method 8081 is used to determine the concentrations of various organochlorine,pesticides in extracts from solid and liquid matrices, using fused-silica, open-tubular, capillary,columns with electron capture detectors (ECD). When compared to the packed columns, these,columns offer improved resolution, better selectivity, increased sensitivity, and faster analysis. The,compounds listed below may be determined by either a single- or dual-column analysis system.,Compound CAS Registry No.,Aldrin 309-00-2,"-BHC 319-84-6,$-BHC 319-85-7,(-BHC (Lindane) 58-89-9,*-BHC 319-86-8,Chlorobenzilate 510-15-6,"-Chlordane 5103-71-9,(-Chlordane 5103-74-2,Chlordane - not otherwise specified 57-74-9,DBCP 96-12-8,4,4'-DDD 72-54-8,4,4'-DDE 72-55-9,4,4'-DDT 50-29-3,Diallate 2303-16-4,Dieldrin 60-57-1,Endosulfan I 959-98-8,Endosulfan II 33213-65-9,Endosulfan sulfate 1031-07-8,Endrin 72-20-8,Endrin aldehyde 7421-93-4,Endrin ketone 53494-70-5,Heptachlor 76-44-8,Heptachlor epoxide 1024-57-3,Hexachlorobenzene 118-74-1,Hexachlorocyclopentadiene 77-47-4,Isodrin 465-73-6,Methoxychlor 72-43-5,Toxaphene 8001-35-2,1.2 This revision of Method 8081 no longer includes the PCBs as Aroclors in the list of target,analytes. The analysis of PCBs should be undertaken using Method 8082, which includes specific,cleanup and quantitation procedures designed for PCB analysis. This change was made to obtain,PCB data of better quality and to eliminate the complications inherent in a combined organochlorine,pesticide and PCB method. Therefore, if the presence of PCBs is expected, use Method 8082 for,CD-ROM 8081A - 2 Revision 1,December 1996,PCB analyses, and this method (8081) for the organochlorine pesticides. If there is no information,of the likely presence of PCBs, either employ a PCB-specific screening procedure such as an,immunoassay (e.g., Method 4020), or split the sample extract prior to any cleanup steps, and,process part of the extract for organochlorine pesticide analysis and the other portion for PCB,analysis using Method 8082.,1.3 The analyst must select columns, detectors and calibration procedures most appropriate,for the specific analytes of interest in a study. Matrix-specific performance data must be established,and the stability of the analytical system and instrument calibration must be established for each,analytical matrix (e.g., hexane solutions from sample extractions, diluted oil samples, etc.).,1.4 Although performance data are presented for many of the target analytes, it is unlikely,that all of them could be determined in a single analysis. The chemical and chromatographic,behaviors of many of these chemicals can result in co-elution of some target analytes. Several,cleanup/fractionation schemes are provided in this method and in Method 3600.,1.5 Several multi-component mixtures (i.e., Chlordane and Toxaphene) are listed as target,analytes. When samples contain more than one multi-component analyte, a higher level of analyst,expertise is required to attain acceptable levels of qualitative and quantitative analysis. The same,is true of multi-component analytes that have been subjected to environmental degradation or,degradation by treatment technologies. These result in "weathered" multi-component mixtures that,may have significant differences in peak patterns than those of standards.,1.6 Compound identification based on single-column analysis should be confirmed on a,second column, or should be supported by at least one other qualitative technique. This method,describes analytical conditions for a second gas chromatographic column that can be used to,confirm the measurements made with the primary column. GC/MS Method 8270 is also,recommended as a confirmation technique, if sensitivity permits (Sec. 8.0).,1.7 This method includes a dual-column option. The option allows a hardware configuration,of two analytical columns joined to a single injection port. The option allows one injection to be used,for dual-column analysis. Analysts are cautioned that the dual-column option may not be appropriate,when the instrument is subject to mechanical stress, many samples are to be run in a short period,or when contaminated samples are analyzed.,1.8 This method is restricted to use by, or under the supervision of, analysts experienced in,the use of gas chromatographs (GC) and skilled in the interpretation of gas chromatograms. Each,analyst must demonstrate the ability to generate acceptable results with this method.,1.9 Extracts suitable for analysis by this method may also be anal……

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