EPA Method 622 Organophosphorus Pesticides
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ID： |
33C946CCCF0D49D8A6614363046E1B35 |
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文件大小(MB)： |
0.11 |
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页数： |
21 |
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文件格式： |
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日期： |
2008-2-26 |
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购买： |
文本摘录（文本识别可能有误，但文件阅览显示及打印正常，pdf文件可进行文字搜索定位）：
Method 622,The Determination of,Organophosphorus Pesticides in,Municipal and Industrial,Wastewater,Method 622,The Determination of Organophosphorus Pesticides in Municipal and,Industrial Wastewater,1. SCOPE AND APPLICATION,1.1 This method covers the determination of certain organophosphorus pesticides. The,following parameters can be determined by this method:,Parameter STORET No. CAS No.,Azinphos methyl 39580 86-50-0,Bolstar ) 35400-43-2,Chlorpyrifos ) 2921-88-2,Chlorpyrifos methyl ) 5598-13-0,Coumaphos 81293 56-72-4,Demeton 39560 8065-48-3,Diazinon 39570 333-41-5,Dichlorvos ) 62-73-7,Disulfoton 39010 298-04-4,Ethoprop ) 13194-48-4,Fensulfothion ) 115-90-2,Fenthion 39016 55-38-9,Merphos 39019 150-50-5,Mevinphos ) 7786-34-7,Naled ) 300-76-5,Parathion methyl 39600 298-00-0,Phorate 39023 298-02-2,Ronnel 39357 299-84-3,Stirofos ) 961-11-5,Tokuthion ) 34643-46-4,Trichloronate ) 327-98-0,1.2 This is a gas chromatographic (GC) method applicable to the determination of the,compounds listed above in industrial and municipal discharges as provided under,40 CFR 136.1. Any modification of this method beyond those expressly permitted shall,be considered a major modification subject to application and approval of alternate test,procedures under 40 CFR 136.4 and 136.5.,1.3 The estimated method detection limit (MDL, defined in Section 15) for each parameter,is listed in Table 1. The MDL for a specific wastewater may differ from those listed,depending upon the nature of interferences in the sample matrix.,1.4 The sample extraction and concentration steps in this method are essentially the same as,several others in the 600-series methods. Thus, a single sample may be extracted to,measure the parameters included in the scope of each of these methods. When cleanup,is required, the concentration levels must be high enough to permit selecting aliquots, as,necessary, in order to apply appropriate cleanup procedures. Under gas,Method 622,chromatography, the analyst is allowed the latitude to select chromatographic conditions,appropriate for the simultaneous measurement of combinations of these parameters (see,Section 12).,1.5 This method is restricted to use by or under the supervision of analysts experienced in,the use of gas chromatography and in the interpretation of gas chromatograms. Each,analyst must demonstrate the ability to generate acceptable results with this method,using the procedure described in Section 8.2.,1.6 When this method is used to analyze unfamiliar samples for any or all of the compounds,above, compound identifications should be supported by at least one additional,qualitative technique. Section 14 provides gas chromatograph/mass spectrometer,(GC/MS) criteria appropriate for the qualitative confirmation of compound,identifications.,2. SUMMARY OF METHOD,2.1 A measured volume of sample, approximately 1 L, is extracted with 15% methylene,chloride using a separatory funnel. The methylene chloride extract is dried and,exchanged to hexane during concentration to a volume of 10 mL or less. Gas,chromatographic conditions are described which permit the separation and measurement,of the compounds in the extract by gas chromatography with a thermionic bead or flame,photometric detector in the phosphorus mode.1,3. INTERFERENCES,3.1 Method interferences may be caused by contaminants in solvents, reagents, glassware,and other sample-processing apparatus that lead to discrete artifacts or elevated baselines,in gas chromatograms. All reagents and apparatus must be routinely demonstrated to,be free from interferences under the conditions of the analysis by running laboratory,reagent blanks as described in Section 8.5.,3.1.1 Glassware must be scrupulously cleaned.2 Clean all glassware as soon as possible,after use by thoroughly rinsing with the last solvent used in it. Follow by,washing with hot water and detergent and thorough rinsing with tap and reagent,water. Drain dry, and heat in an oven or muffle furnace at 400°C for 15 to 30,minutes. Do not heat volumetric ware. Thermally stable materials, such as PCBs,may not be eliminated by this treatment. Thorough rinsing with acetone and,pesticide-quality hexane may be substituted for the heating. After drying and,cooling, seal and store glassware in a clean environment to prevent any,accumulation of dust or other contaminants. Store inverted or capped with,aluminum foil.,3.1.2 The use of high-purity reagents and solvents helps to minimize interference,problems. Purification of solvents by distillation in all-glass systems may be,required.,Method 622,3.2 Matrix interferences may be caused by contaminants that are coextracted from the,sample. Th……
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