1、Designation: D4861 11D4861 17Standard 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 adoption or,
2、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 pesticides and p
3、olychlorinated 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, andpolychlorinated naphthalen
4、es may be efficiently collected from air by this practice, but guidance on their analytical determinationis not covered by this practice.1.2 The sampling and analysis of PCBs in air can be more complicated than sampling PCBs in solid media (for example, soils,building materials) or liquids (for exam
5、ple, transformer fluids). PCBs in solid or liquid material are typically analyzed usingAroclor2 distillation groups in chromatograms. In contrast, recent research has shown that analysis of PCBs in air samples byGC/ECD has also been found to exhibit potential uncertainties due to changes in the PCB
6、patterns, differences in responses indistillation groups, peak co-elutions and differences in response factors within a homolog group (1, 2).3 As such it is recommendedthat PCBs in air not be quantified using AroclorTM distillation groups. In addition, it is recommended that analysis of PCBs inair b
7、e done using GC/MS rather than GC/ECD. Any mention, to outdated practices for “Aroclor” and GC/ECD analysis of PCBsherein are retained solely for historical perspective.1.3 A complete listing of pesticides and other semivolatile organic chemicals for which this practice has been tested is shownin Ta
8、ble 1.1.4 This practice is based on the collection of chemicals from air onto polyurethane foam (PUF) or a combination of PUF andgranular sorbent.sorbent (for example, diphenyl oxide, styrene-divinylbenzene), or a granular sorbent alone.1.5 This practice is applicable to multicomponent atmospheres,
9、0.001 to 50-g/m3 concentrations, and 4 to 24-h samplingperiods. The limit of detection will depend on the nature of the analyte and the length of the sampling period.1.6 The analytical method(s) recommended will depend on the specific chemical(s) sought, the concentration level, and thedegree of spe
10、cificity required.1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.8 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 stand
11、ard to establish appropriate safety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use. For specific hazards statements, see 10.24 and A1.1.1.9 This international standard was developed in accordance with internationally recognized
12、 principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:4D1193 Specification for Reag
13、ent WaterD1356 Terminology Relating to Sampling and Analysis of Atmospheres1 This 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, 2011Dec. 15, 2017. Published March 2011Mar
14、ch 2018. Originally approved in 1991. Last previous edition approved in 20052011 asD4861 05.D4861 11. DOI: 10.1520/D4861-11.10.1520/D4861-17.2 A trade name formerly used by Monsanto Corporation, Creve Coeur, MO.3 The boldface numbers in parentheses refer to the list of references at the end of this
15、standard.4 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intende
16、d only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current
17、versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1D3686 Practice for SamplingAtmospheres to Collect Organic Compound Vapors (Activated Charcoal TubeAd
18、sorption Method)D3687 Practice for Analysis of Organic Compound Vapors Collected by the Activated Charcoal Tube Adsorption MethodD4185 Test Method for Measurement of Metals in Workplace Atmospheres by Flame Atomic Absorption SpectrophotometryE355 Practice for Gas Chromatography Terms and Relationshi
19、ps2.2 EPA Methods and Standards:EPA 600/R-96/010b Compendium of Methods for the Determination to Toxic Organic Compounds in Ambient Air5EPA 821/C-99-004 Methods and Guidance for Analysis of Water, Versions 26EPA SW-846 Test Methods for Evaluating Solid Waste Physical Chemical Methods40 CFR 136 EPA O
20、rganic Chemical Analysis of Municipal and Industrial Wastewater72.3 NIOSH Methods:NIOSH Manual of Analytical Methods8NOTE 1ASTM does not recommend NIOSH 5503 for PCB analysis due to Aroclor quantitation and GC-ECDGC/ECD analysis.3. Terminology3.1 DefinitionsRefer to Terminology D1356 and Practice E3
21、55 for definitions of terms used in this practice.3.2 Definitions of Terms Specific to This Standard:5 Also available at http:/www.epa.gov/ttnamti1/files/ambient/airtox/tocomp99.pdf6 NTIS PB99-500209 (see http:/www.ntis.gov/products/epa-water-methods.aspx)7 Also available at http:/ecfr.gpoaccess.gov
22、/cgi/t/text/text-idx?c=ecfr ECD = electron capture detector; FPD = flame photometric detector; HPLC = high-performance liquid chromatography; NPD = nitrogen-phosphorus detector; UV = ultraviolet absorption detector. (GC/MS (gas chromatography/mass spectrometry) is always recommended, if available.)B
23、 Using PUF/2,6-diphenyl-p-phenylene oxide “sandwich” trap.C Compound is very unstable in solution.DDerivatization necessary for free acid and salts.D4861 1723.2.1 dynamic retention effciencyability of the sampling medium to retain the solution spike when air or nitrogen is drawnthrough the sampling
24、cartridge under normal operating conditions and for the duration of the test period. The dynamic RE isnormally equal to or less than the SE.3.2.2 relative retention time, (RRT)ratio of RTs for two chemicals for the same chromatographic column and carrier gas flowrate, where the denominator represent
25、s a reference chemical.3.2.3 retention effciency, (RE)ability of the sampling medium to retain a compound added (spiked) to it in liquid solution.3.2.4 retention time, (RT)time to elute a specific chemical from a chromatographic column, for a specific carrier gas flow rate,measured from the time the
26、 chemical is injected into the gas stream until it appears at the detector.3.2.5 sampling effciency, (SE)ability of the sampling medium to trap vapors of interest. The percentage of the analyte ofinterest collected and retained by the sampling medium when it is introduced as a vapor in air or nitrog
27、en into the air sampler andthe sampler is operated under normal conditions for a period of time equal to or greater than that required for the intended use isindicated by % SE.3.2.6 static retention effciencyability of the sampling medium to retain the solution spike when the sampling cartridge isst
28、ored under clean, quiescent conditions for the duration of the test period.4. Summary of Practice4.1 Alow-volume (1 to 5 L/min) sampler is used to collect vapors on a sorbent cartridge containing PUF or PUF in combinationwith another solid sorbent. sorbent, or another solid sorbent alone. Airborne p
29、articles may also be collected, but the samplingefficiency is not known. The method is adopted from Ref (13) and 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-l
30、iquid chromatography (GC) coupled with an 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
31、an ultraviolet (UV) detector or electrochemical detectormay be preferable. For PCBs, MS detection is the recommended detector with congener or homolog based quantitation.4.3 Interferences resulting from analytes having similar RTs during GC are resolved by improving the resolution or separation,such
32、 as by changing the chromatographic column or operating parameters, or by fractionating the sample by columnchromatography.chromatography, or by mass spectrometric analysis.5. Significance and Use5.1 This practice is recommended for use primarily for non-occupational exposure monitoring in domiciles
33、, 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 respiratory exposure monitoring.5.3 Abroad spectrum of pesticides are commonly used in and around the house and for ins
34、ect control in public and commercialbuildings. Other semivolatile organic chemicals, such as PCBs, are also often present in indoor air, particularly in large officebuildings. This practice promotes needed precision and bias in the determination of many of these airborne chemicals.6. Interferences6.
35、1 Any gas or liquid chromatographic separation of complex mixtures of organic chemicals is subject to serious interferenceproblems due to coelutioncoelutions of two or more compounds. The use of capillary or microbore columns with superiorresolution or two columns of different polarity will frequent
36、ly 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 determined.6.2 The ECD responds to a wide variety of organic compounds. It is likely that such compounds will
37、 be encountered asinterferences during GC-ECDGC/ECD analysis. The NPD, FPD, and HECD detectors are element specific, but are still subject tointerferences. UV detectors for HPLC are nearly universal and the electrochemical detector may also respond to a variety ofchemicals. Mass spectrometric analys
38、es 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 cause difficulty in accurately quantifying a particular formulation in a multiple component mixtu
39、re. PCBs may also interferewith the determination of pesticides. The analysis of PCBs in air samples by GC/ECD is not recommended.6.4 Contamination of glassware and sampling apparatus with traces of pesticides or PCBs can be a major source of error,particularly at lower analyte concentrations. Caref
40、ul 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:D4861 1736.5.1 Polar compounds, including certain pesticides (for example, organ
41、ophosphorus and carbamate classes) can be removed bycolumn chromatography on alumina. This sample cleanup will permit the analysis of most organochlorine pesticides and PCBs(24).6.5.2 PCBs may be separated from organochlorine pesticides by column chromatography on silicic acid. See Refs (35) and (46
42、).6.5.3 Many pesticides can be fractionated into groups by column chromatography on Florisil9 (46).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 quiet andunobtrusive.7.1.2 Sampling Cartridge, constructed f
43、rom 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 under slight compression insid
44、e 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. They may be cut by one of the
45、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.7.1.3.2 With a hot-wire cutter. Care is required to prevent thermal degradation of the foam.7.1.3.3 With scissors, while compressed between two
46、22-mm circular templates.7.1.4 Alternatively, pre-extracted PUF plugs and glass cartridges may be obtained commercially from one of several vendors.Other combinations (that is, PUF/solid sorbent/PUF or solid sorbents only, with glass, polymer or metal cartridge casings) mayalso be used.7.1.5 Particl
47、e Filter, Particle Filter, if desired, may be utilized. The collection efficiency of PUF for small-diameter (0.1 to 1m) airborne particles is only about 20 % (57). However, most pesticides and PCBs exist in air under steady-state conditions,primarily as vapors (68). Most particulate-associated pesti
48、cides or PCBs, if any, will also tend to be vaporized from filters aftercollection (79). Collocated sampling with and without a quartz-fiber pre-filter has yielded indistinguishable results for a broadspectrum of pesticides and PCBs found in indoor air (810).7.1.5.1 An open-face filter may be attach
49、ed to the sampling cartridge by means of a union for 25.4-mm tubing. A 32-mmdiameter micro-quartz-fibre, binderless, acid-washed filter is placed in the open end of the union and supported by means of ascreen or perforated metal plate (for example, a 304 stainless steel disk, 0.8-mm thick with 1.6-mm diameter round perforationsat 20 holes/cm2, 41 % open area).A32-mm fluoroelastomeric or polytetrafluoroethylene (PTFE) O-ring is placed between the filterand outer nut to affect a seal (see Fig. 2).7.1.6 Size-Selective Impactor Inlet with particle-size cut-points
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