1、Designation:D486105 Designation: D4861 11Standard Practice forSampling and Selection of Analytical Techniques forPesticides and Polychlorinated Biphenyls in Air1This standard is issued under the fixed designation D4861; the number immediately following the designation indicates the year oforiginal a
2、doption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers the sampling of air for a variety of common pest
3、icides and polychlorinated biphenyls (PCBs) andprovides guidance on the selection of appropriate analytical measurement methods. Other compounds such as polychlorinateddibenzodioxins/furans, polybrominated biphenyls, polybrominated diphenyl ethers, polycyclic aromatic hydrocarbons, andpolychlorinate
4、d naphthalenes may be efficiently collected from air by this practice, but guidance on their analytical determinationis not covered by this practice.1.2 A complete listing of pesticides and other semivolatile organic chemicals for which this practice has been tested is shownin Table 1.1.3 This pract
5、ice is based on the collection of chemicals from air onto polyurethane foam (PUF) or a combination of PUF andgranular sorbent.1.4 This practice is applicable to multicomponent atmospheres, 0.001 to 50-g/m3concentrations, and 4 to 24-h samplingperiods. The limit of detection will depend on the nature
6、 of the analyte and the length of the sampling period.1.5 The analytical method(s) recommended will depend on the specific chemical(s) sought, the concentration level, and thedegree of specificity required.1.61.6 The values stated in SI units are to be regarded as standard. No other units of measure
7、ment are included in this standard.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitat
8、ions prior to use. For specific hazards statements, see 10.24 and A1.1.2. Referenced Documents2.1 ASTM Standards:2D1193 Specification for Reagent WaterD1356 Terminology Relating to Sampling and Analysis of AtmospheresD3686 Practice for Sampling Atmospheres to Collect Organic Compound Vapors (Activat
9、ed Charcoal Tube AdsorptionMethod)D3687 Practice for Analysis of Organic Compound Vapors Collected by the Activated Charcoal Tube Adsorption MethodD4185 Practice for Measurement of Metals in Workplace Atmospheres by Flame Atomic Absorption SpectrophotometryE355 Practice for Gas Chromatography Terms
10、and Relationships2.2 EPA Methods and Standards:EPA 600/R-96/010b Compendium of Methods for the Determination to Toxic Organic Compounds in Ambient Air3EPA 821/C-99-004 Methods and Guidance for Analysis of Water, Versions 24EPA SW-846 Test Methods for Evaluating Solid Waste Physical Chemical Methods4
11、0 CFR 136 EPA Organic Chemical Analysis of Municipal and Industrial Wastewater51This practice is under the jurisdiction of ASTM Committee D22 on Air Quality and is the direct responsibility of Subcommittee D22.05 on Indoor Air.Current edition approved March 1, 2005.2011. Published March 2005.2011. O
12、riginally approved in 1991. Last previous edition approved in 20002005 as D4861 - 005.DOI: 10.1520/D4861-05.10.1520/D4861-11.2For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, re
13、fer to the standards Document Summary page on the ASTM website.3Available from Superintendent of Documents, U.S. Government Printing Office, Washington, DC 20402.3Also available at http:/www.epa.gov/ttnamti1/files/ambient/airtox/tocomp99.pdf4Also available at http:/www.epa.gov/ttn/amtic/airtox.html4
14、NTIS PB99-500209 (see http:/www.ntis.gov/products/epa-water-methods.aspx)5NTIS PB99-500209INQ (see http:/www.ntis.gov/product/epa-water-methods.htm)5Also available at http:/ecfr.gpoaccess.gov/cgi/t/text/text-idx?c=ecfr ECD = electron capture detector; FPD = flame photometric detector; HPLC = high-pe
15、rformance liquid chromatography; NPD = nitrogen-phosphorus detector; UV = ultraviolet absorption detector. (GC/MS (gas chromatography/mass spectrometry) is always recommended, if available.)BUsing PUF/2,6-diphenyl-p-phenylene oxide “sandwich” trap.CCompound is very unstable in solution.DDerivatizati
16、on necessary for free acid and salts.D4861 112adopted from Ref (1)7and is the basis of EPA 600/R-96/010b, Method TO-10A.4.2 Pesticides and other chemicals are extracted from the sorbent cartridge with 5 % diethyl ether in hexane and may bedetermined by gas-liquid chromatography (GC) coupled with an
17、electron capture detector (ECD), nitrogen-phosphorus detector(NPD), flame photometric detector (FPD), Hall electrolytic conductivity detector (HECD), or a mass spectrometer (MS). For somepesticides, high-performance liquid chromatography (HPLC) coupled with an ultraviolet (UV) detector or electroche
18、mical detectormay be preferable.4.3 Interferences resulting from analytes having similar RTs during GC are resolved by improving the resolution or separation,such as by changing the chromatographic column or operating parameters, or by fractionating the sample by columnchromatography.5. Significance
19、 and Use5.1 This practice is recommended for use primarily for non-occupational exposure monitoring in domiciles, public accessbuildings, and offices.5.2 The methods described in this practice have been successfully applied to measurement of pesticides and PCBs in outdoorair and for personal respira
20、tory exposure monitoring.5.3 Abroad spectrum of pesticides are commonly used in and around the house and for insect control in public and commercialbuildings. Other semivolatile organic chemicals, such as PCBs, are also often present in indoor air, particularly in large officebuildings. This practic
21、e promotes needed precision and bias in the determination of many of these airborne chemicals.6. Interferences6.1 Any gas or liquid chromatographic separation of complex mixtures of organic chemicals is subject to serious interferenceproblems due to coelution of two or more compounds. The use of cap
22、illary or microbore columns with superior resolution or twocolumns of different polarity will frequently eliminate these problems.6.1.1 Selectivity may be further enhanced by use of a MS in a selected ion monitoring (SIM) mode as the GC detector. In thismode, coeluting compounds can often be determi
23、ned.6.2 The ECD responds to a wide variety of organic compounds. It is likely that such compounds will be encountered asinterferences during GC-ECD analysis. The NPD, FPD, and HECD detectors are element specific, but are still subject tointerferences. UV detectors for HPLC are nearly universal and t
24、he electrochemical detector may also respond to a variety ofchemicals. Mass spectrometric analyses will generally provide for positive identification of specific compounds.6.3 PCBs and certain organochlorine pesticides (for example, chlordane) are complex mixtures of individual compounds, whichcan c
25、ause difficulty in accurately quantifying a particular formulation in a multiple component mixture. PCBs may also interferewith the determination of pesticides.6.4 Contamination of glassware and sampling apparatus with traces of pesticides or PCBs can be a major source of error,particularly at lower
26、 analyte concentrations. Careful attention to cleaning and handling procedures is required in all steps of thesampling and analysis to minimize this source of error.6.5 General approaches that can be followed to minimize interferences are as follows:6.5.1 Polar compounds, including certain pesticide
27、s (for example, organophosphorus and carbamate classes) can be removed bycolumn chromatography on alumina. This sample cleanup will permit the analysis of most organochlorine pesticides and PCBs (2).6.5.2 PCBs may be separated from organochlorine pesticides by column chromatography on silicic acid.
28、See Refs (3) and (4).6.5.3 Many pesticides can be fractionated into groups by column chromatography on Florisil-PRFlorisil8(4).7. Apparatus7.1 Air Sampler:7.1.1 Sampling Pump, with a flow rate of 1 to 5 L/min. The pump should provide a constant air flow (#65 %) and be quietand unobtrusive.7.1.2 Samp
29、ling Cartridge, constructed from a 20-mm (inside diameter) by 10-cm borosilicate glass tube drawn down to a 7-mm(outside diameter) open connection for attachment to the pump by way of flexible tubing (see Fig. 1).7.1.3 Sorbent, PUF, cut into a cylinder 22 mm in diameter and 7.6-cm long, and fitted u
30、nder slight compression inside thecartridge. The PUF should be of the polyether type, density 0.022 g/cm3. This is the type of foam used for furniture upholstery,pillows, and mattresses. The PUF cylinders (plugs) should be cut slightly larger in diameter than the internal diameter of thecartridge. T
31、hey may be cut by one of the following means:7.1.3.1 With a high-speed cutting tool, such as a motorized cork borer. Distilled Type II water should be used to lubricate thecutting tool.7Also available at http:/www.cdc.gov/niosh/nmam7The boldface numbers in parentheses refer to the list of references
32、 at the end of this standard.8The boldface numbers in parentheses refer to the list of references at the end of this standard.8Florisil is a trademark of the U.S Silica Co., Berkeley Springs, WV. It is a natural magnesium silicate and is available from several commercial suppliers.D4861 1137.1.3.2 W
33、ith a hot-wire cutter. Care is required to prevent thermal degradation of the foam.7.1.3.3 With scissors, while compressed between two 22-mm circular templates.7.1.4 Alternatively, pre-extracted PUF plugs and glass cartridges may be obtained commercially from one of several vendors.7.1.5 Particle Fi
34、lter, if desired, may be utilized. The collection efficiency of PUF for small-diameter (0.1 to 1 m) airborneparticles is only about 20 % (5). However, most pesticides and PCBs exist in air under steady-state conditions, primarily as vapors(6). Most particulate-associated pesticides or PCBs, if any,
35、will also tend to be vaporized from filters after collection (7). Collocatedsampling with and without a quartz-fiber pre-filter has yielded indistinguishable results for a broad spectrum of pesticides andPCBs found in indoor air (8).7.1.5.1 An open-face filter may be attached to the sampling cartrid
36、ge by means of a union for 1-in. 25.4-mm 25.4-mm tubing.A32-mm diameter micro-quartz-fibre, binderless, acid-washed filter is placed in the open end of the union and supported by meansof a screen or perforated metal plate for(for example, a 304 stainless steel disk, 0.0312-in. 0.8-mm 0.8-mm thick wi
37、th -in.1.6-mm 1.6-mm diameter round perforations at 132 holes/in.20 holes/cm220 holes/cm2, , 41 % open area.area). A 32-mmfluoroelastomeric or polytetrafluoroethylene (PTFE) O-ring is placed between the filter and outer nut to effectaffect a seal (see Fig.2).7.1.6 Size-Selective Impactor Inlet with
38、particle-size cut-points of either 2.5 or 10 m mean diameter at a sampling rate of 4L/min may be used to exclude non-respirable airborne particulate matter (9, 10). An example of a sampler with a size-selectiveinlet, particle filter support, sampling cartridge holder is shown in Fig. 3. This samplin
39、g cartridge is available commercially.7.2 Equipment and Reagents for Sample Extraction and Concentration:7.2.1 Round Bottom Flasks, 500 mL, $ (standard paper glass joint) 24/40 joints,7.2.2 Capacity Soxhlet Extractors , 300 mL, with reflux condensers,7.2.3 Kuderna-Danish Concentrators , 500 mL, with
40、 Snyder columns,7.2.4 Graduated Concentrator Tubes, 10 mL, with $ 19/22 stoppers,7.2.5 Graduated Concentrator Tubes, 1 mL, with $ 14/20 stoppers,7.2.6 TFE-fluorocarbon Tape,12 in., , 14 mm,7.2.7 Filter Tubes, size 40 mm (inside diameter) by 80 mm,7.2.8 Vials, serum, 1 mL and 5 mL, fitted with caps l
41、ined with TFE-fluorocarbon,7.2.9 Pasteur Pipets,30cm,7.2.10 Glass Wool, fired at 500C,7.2.11 Boiling Granules, fired at 500C,7.2.12 Forceps, stainless steel, 23 cm,7.2.13 Gloves, latex or polyvinyl acetate,7.2.14 Steam Bath,7.2.15 Heating Mantles, 500-mL size,7.2.16 Analytical Evaporator, nitrogen b
42、low-down apparatus with adjustable flow control and water bath with 65Ctemperature control.7.2.17 Acetone, pesticide quality97.2.18 n-Hexane, pesticide quality,97.2.19 Diethyl Ether, preserved with 2 % ethanol,7.2.20 Sodium Sulfate, anhydrous, analytical grade, and7.2.21 Solvents for HPLC, if requir
43、ed.9Florisil is a trademark of the U.S Silica Co., Berkeley Springs, WV. It is a natural magnesium silicate and is available from several commercial suppliers.9Glass distilled and certified for pesticides analysis by GC/ECD.FIG. 1 PUF Sampling Cartridge (a) and PUF “Sandwich” Sampling Cartridge (b)F
44、IG. 2 Open-Face Filter Assembly: (a) Sampling Cartridge, (b) Inner Nut, (c) Back Ferrule, (d) Front Ferrule, (e) Union, (f) FrontFerrule, (g) Filter Support, (h) Filter, (i) Fluoroelastomeric or PTFE O-ring, (j) Outer NutD4861 1147.3 Purity of ReagentsUnless otherwise stated, all reagents shall conf
45、orm to the specifications of the Committee onAnalyticalReagents of the American Chemical Society, where such specifications are available.10Other grades may be used, provided it isascertained that use of the reagent does not lessen the accuracy of the test method.7.4 Purity of WaterReferences to dis
46、tilled water shall be understood to mean distilled water, which is Type II reagent waterconforming to Specification D1193.7.5 Equipment for Analysis:7.5.1 Gas Chromatograph (GC) with appropriate detector(s) and either an isothermally controlled or temperature programmedheating oven. Improved detecti
47、on limits may be obtained with a GC equipped with a cool on-column or splitless injector.7.5.2 Gas Chromatographic Columns, such as a 0.25 or 0.32-mm (inside diameter) by 30-m poly(5 %-diphenyl-95 %-dimethylsiloxane)11, (50 %-phenyl)-methylpolysilozane12fused-silica, and others are commercially avai
48、lable.7.5.3 HPLC Column, such as a 4.6-mm by 15-cm reversed-phase octadecyldimethylsilane (C-18) or porous silica gel. Othercolumns may also provide acceptable results.7.5.4 Microsyringes, 5-L volume or other appropriate sizes.8. Sampling Procedure8.1 For initial cleanup place the PUF plug in a Soxh
49、let extractor and extract with acetone for 14 to 24 h at 4 to 6 cycles/h. (Ifcommercially pre-extracted PUF plugs are used, extraction with acetone is not required.) Follow with a 16-h Soxhlet extractionwith 5 % diethyl ether in n-hexane. When cartridges are reused, 5 % ether in n-hexane can be used as the cleanup solvent.8.2 Place the extracted PUF plugs in a vacuum oven connected to a water aspirator and dry at room temperature for 2 to 4 h(until no solvent odor is detected). Alternatively, they may be dried at room temperature in an air-tight container
