1、Designation: D7771 13D7771 15Standard Test Method forDetermination of Benzo-Pyrene (BaP) Content in CarbonBlack1This standard is issued under the fixed designation D7771; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of
2、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 test method covers the qualitative and quantitative determination of only benzo-pyrene (BaP), a specific polycycl
3、icaromatic hydrocarbon (PAH), on carbon black. The procedure involves Soxhlet extraction with toluene and analysis by gaschromatography with mass spectrometry (GC/MS). This method is not intended to test for U.S. Food and Drug Administration(FDA 21 CFR 178.3297) compliance of carbon blacks used for
4、indirect food contact applications.1.2 UnitsThe values stated in SI units are to be regarded as the standard. No other units of measurement are included in thisstandard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
5、of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D4483 Practice for Evaluating Precision for Test Method Standards in the Rubber and Carbon Black Manufact
6、uring Industries2.2 EPA Standard:3Method 8270D Semivolatile Organic Compounds by Gas Chromatography/Mass Spectrometry (GC/MS)2.3 Federal Standard:21 CFR 178.3297 Indirect Food Additives: Adjuvants, Productions Aids, and Sanitizers, Colorants for Polymers43. Terminology3.1 Definitions of Terms Specif
7、ic to This Standard:3.1.1 benzo-pyrene, BaP, nalso known as 3,4-benzopyrene or benzo-a-pyrene is a specific polycyclic aromatic hydrocarbon(PAH) or polynuclear aromatic hydrocarbon that consist of fused aromatic rings with no heteroatom or substituent.3.1.1.1 DiscussionPAHs naturally occur in oil, c
8、oal, and tar deposits; are produced by the incomplete combustion of hydrocarbons; and occur in manyother products and processes. BaP is a pentacyclic PAH with the formula C20H12, related to pyrene by fusion of a phenylene groupin the alpha position.1 This test method is under the jurisdiction of AST
9、M Committee D24 on Carbon Black and is the direct responsibility of Subcommittee D24.66 on Environment, Health,and Safety.Current edition approved Nov. 1, 2013Jan. 1, 2015. Published November 2013February 2015. Originally approved in 2011. Last previous edition approved in 20112013as D7771 11.D7771
10、13. DOI: 10.1520/D7771-13.10.1520/D7771-15.2 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.3 Available from U
11、nited States Environmental Protection Agency (EPA), Ariel Rios Bldg., 1200 Pennsylvania Ave., NW, Washington, DC 20004, http:/www.epa.gov/epaoswer/hazwaste/test/new-meth.htm#8270D.4 Available from the U.S. Government Printing Office, Superintendent of Documents, 732 N. Capital St., NW., Washington,
12、DC 20402-0001.This document is not an ASTM standard and is intended 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 con
13、sult prior editions as appropriate. In all cases only the current 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 States14. Summary of Test Method4.1 A por
14、tion of carbon black is Soxhlet extracted Soxhlet-extracted with toluene for a specified period of time. The resultantextract is purified by solid-phase extraction (SPE), concentrated down to a known volume, 16 h. The extract is concentrated andsubsequently analyzed for BaP by gas chromatography wit
15、h mass spectrometry (GC/MS). The BaP quantification is performed bythe means of a deuterated internal standard (isotope dilution).an internal standard.5. Significance and Use5.1 This test procedure is used to determine the concentration of BaP extracted from carbon black by the means of a Soxhletext
16、raction apparatus with toluene.6. Apparatus6.1 Soxhlet Extractor with Reflux Condenser, 50- or 100-cm3 capacity.6.2 Extraction Thimbles, glass or cellulose, approximately 50- to 70-cm3 capacity. For instance, glass extraction thimble of35-mm diameter by 90-mm height with course porosity (70 to 100 m
17、 similar to Ace Glass Size C, Porosity B, Code-14).6.3 Heating Mantle, compatible with boiling flask described in 6.4.6.4 Boiling Flasks for Soxhlet, for example, 250 cm3.6.5 Glass Beads, approximately 180 to 250 m (60/80 mesh) if glass thimbles are used. Need to be very clean or tolueneextracted.6.
18、6 PTFE or Glass Boiling Beads, approximately 3 mm.6.7 Glass Wool, need to be very clean or toluene extracted.6.8 Rotary Evaporator, with temperature-controlled water bath, automatic pressure regulation, and solvent-proof membranevacuum pump.6.9 Nitrogen Blow-Down Apparatus, equipped with a controlle
19、d water bath and nitrogen pressure control.6.10 Pear-Shaped Flasks for Rotary Evaporator, for example, 25, 50, and 100 cm3 .6.11 GC/MS, with autosampler.6.11.1 MS with electron impact (EI) capability and single-ion monitoring (SIM) mode.6.11.2 GC Capillary Column, usually a nonpolar GC column compos
20、ed of 5 % phenyl-methyl silicone coating is used for PAHanalysis.6.11.3 Deactivated Straight Borosilicate Liner with Small Piece of Deactivated Glass WoolThis liner may be used as long aspeak resolution is satisfactory.6.11.4 Alternative liner is a split/splitless nondeactivated liner with glass woo
21、l (4-mm internal diameter, straight liner). Thisshall be deactivated with a silanizing agent before use. Another alternative is a split/splitless liner with fluorocarbon liner seals.Such a liner will already contain conditioned silanized glass wool. Other liners can be used if they produce acceptabl
22、e results.6.11.5 Gold-plated seal for GC injector port or similar nonreactive seal.6.11.6 GC/MS amber autosampler vials with polytetrafluoroethylene (PTFE)-coated caps.6.11.7 Crimping tool.6.12 Adjustable Micropipettes, 1000, 200, and 20 L.6.13 Microlitre Syringes of Different Volumes, for example,
23、10 and 100 L.6.14 Amber Glass Vials, approximately 4 cm3 with caps (rubber with PTFE back).6.15 Amber Volumetric Flasks, 2, 3, 5, 10, 25, and 100 cm3.6.16 Analytical Balance, with an accuracy of 0.01 mg.TABLE 1 Native and Deuterated BaP CompoundsPAH CAS# Deuterated PAH CAS#Benzo(a)pyrene 50-32-8 d12
24、-Benzo(a)pyrene 63466-71-7TABLE 1 Native and Deuterated BaP CompoundsNative PAH CAS# Deuterated PAH CAS# C13 LabeledPAH CAS#Benzo-pyrene 50-32-8 d12-Benzo-pyrene 63466-71-7 13C4-Benzo-pyreneNot AvailableD7771 1526.17 Drying Oven, gravity convection type, capable of maintaining 40 6 10C, used for slo
25、wing down the cooling when theglassware is taken out of the muffle furnace.6.18 Furnace, capable of temperature regulation of 500 6 25C, used to burn off organic contamination from glass surfaces.6.19 Manometer, capable of pressure readings in the range of 5 6 0.3 kPa.7. Reagents and Materials7.1 Pu
26、rity of ReagentsReagent-grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that allreagents conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society where suchspecifications are available.5 Other grades may be used, pr
27、ovided it is first ascertained that the reagent is of sufficiently high purityto permit its use without lessening the accuracy of the determination.7.2 Separate stock solutions of the deuterated internal standard (IS) native BaP standards and of the nondeuterated (native) BaPstandards internal stand
28、ard (deuterated or C13-labeled) can be purchased prepared from solid materials or individual solutions(Table 1). A concentration range of 80 to 100 g/ cm3 for both the native BaP and d12-benzo(a)pyrene is recommended. Allpurchased BaP standard materials shall be 98 % pure or better and certified in
29、respect of their purity, concentration level, andauthenticity by the manufacturer.7.2.1 A concentration range of 80 to 100 g/cm3 for the native BaP analyte stock solution is recommended.7.2.2 A similar concentration range of 80 to 100 g/cm3 of the deuterated (d12-benzo-pyrene) or isotopically-labele
30、d(13C4-benzo-pyrene) is recommended for the internal standard (IS) stock solution.7.2.3 All purchased BaP standard materials shall be 98 % pure or better and certified with respect to their purity andconcentration by the manufacturer. Follow the manufacturers recommendation on how best to store the
31、standard stock solutions.It is generally accepted to keep them solutions. Typically, the compounds are protected from light. They should be checkedfrequently for signs of degradation or evaporation, especially just before preparing calibration standards from them. evaporation.The BaP standard stock
32、solutions shall be replaced/recertified on a yearly basis or sooner if comparisons with quality control (QC)samples indicatesindicate a problem.7.3 Toluene, suitable for high resolution gas chromatography analysis (99.99% (99.99 % pure).7.4 Acetone, suitable for high resolution gas chromatography an
33、alysis (99.99% (99.99 % pure).7.5 Helium, GC/MS purity grade.7.6 Nitrogen, analytical purity grade.7.7 Silica Solid-Phase Extractor Cartridges, single-use application, having a volume capacity of approximately 5 cmSilica gelcolumns for Solid Phase Extraction (SPE) removal of polar compounds.3 or 2-
34、to 3-cm length by 1-cm diameter.7.7.1 Silica SPE Cartridges, single-use application, having a volume capacity of approximately 5 to 10 cm3.67.7.1.1 Preparation of Silica SPE CartridgeFollow the manufacturers instruction for preparation and use.The typical methodof preparation is to wet the cartridge
35、 with approximately 10 cm3 of the elution solvent (toluene). Discard the wetting solvent.7.7.2 Alternative SPE Method: Silica Gel/13 % H2O Gravity Column:7.7.2.1 Preparation of a Silica Gel/13 % H2O AdsorbentPour 200 g silica gel (high purity grade, type 60, particle size 0.063to 0.200 mm) into a sc
36、rew cap glass bottle and add 30 g of deionized water in small portions (for example, 2 cm3) using a suitablepipette. After addition of each portion of water, the silica gel bottle is shaken to evenly distribute the wetted silica gel. Noaggregation should occur during this process. If so, shaking mus
37、t be continued until a homogeneous material is obtained. Finally,the closed bottle is shaken for 8 hours by means of an overhead shaker. If properly closed and stored, the adsorbent should be viablefor at least 6 months.7.7.2.2 Preparation of a Silica Gel/13 % H2O Gravity ColumnInsert a glass wool p
38、lug into the bottom of a pipette tip (forexample, 8 to 10 mm inner diameter and 5 cm3 capacity). Place 1 g of the silica gel/13 % H2O in the column and tap the columngently to settle the silica gel. Cover the adsorbent layer with a glass wool plug and pre-elute the column with 5 cm3 of cyclohexane.D
39、iscard the cyclohexane eluate.8. Hazards8.1 This test involves hazardous materials, operations, and equipment. This procedure does not attempt to address the safetyproblems associated with this test.Ahazards review shall be conducted by all personnel performing the test. It is the responsibilityof t
40、he user to review all material safety data sheets (MSDS), manuals, and hazards procedures and establish the appropriate safety5 Reagent Chemicals, American Chemical Society Specifications, American Chemical Society, Washington, DC. For suggestions on the testing of reagents not listed bythe American
41、 Chemical Society, see Analar Standards for Laboratory Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia and NationalFormulary, U.S. Pharmacopeial convention, Inc. (USPC), Rockville, MD.6 The sole source of supply of the Sep-Pak cartridges known to the committee at this ti
42、me is Waters, 34 Maple Street, Milford, MA 01757 (). If you areaware of alternative suppliers, please provide this information to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee,1 which you may attend.D7771 153measu
43、res. Some PAH compounds have been shown to possess mutagenic as well as carcinogenic and teratogenic properties. Assuch, concentrated extracts of carbon blacks containing PAHs also may possess the same harmful properties. Solvents used areflammable. Appropriate personal protection equipment (PPE) sh
44、all be used.9. Preparation of Standard Solutions9.1 The GC/MS instrument is calibrated throughusing five mixturessolutions of the native BaP and deuterated IS. internalstandard (IS). The recommended BaP concentrations are to cover a range of approximately 0.01 0.0125 to 0.81.0 g/cm3 (ppm)while the (
45、ppm). Other concentrations may be used as needed for the application. The IS concentration is kept constant at around0.3 within the calibration range. Preferably the IS concentration is in the middle of the selected calibration range (for example, 0.3to 0.6 g/cm3.).Alower BaP concentration range can
46、 be used for the case of high-purity carbon blacks, but the difference betweenany two concentration levels shall not exceed a factor of four. Furthermore, the blacks. However, the IS concentration shouldmaintain an S/N ratio of at least 15/1 for routine instrument performance. Subsections 9.2 9.49.5
47、 describe the preparation of thevarious solutions required.9.2 Preparation of Native BaP Standard Solutions for CalibrationUsing the native BaP standard stock solution described in7.2, prepare at least 10 cm3 of five toluene solutions in amber glassware at the concentrations suggested in the followi
48、ng. Otherconcentrations may be used but the difference between any two concentration levels shall not exceed a factor of four. Beforediluting to the final solution volume, spike each standard with the appropriate volume (for example, 10 L IS solution describedin 9.3 into 10 cm3 volumetric flask) to
49、give a final IS concentration of 0.500 g/cm3Cap securely the standard solutions, . Otheraliquot volumes and final volumes may be used to obtain the desired concentrations. Cap the standard solutions securely, mixthoroughly, and label.Native BaP Standard 5 0.85 g/cm3Native BaP Standard 4 0.28 g/cm3Native BaP Standard 3 0.09 g/cm3Native BaP Standard 2 0.03 g/cm3Native BaP Standard 1 0.01 g/cm3Native BaP Standard 5 1.00 g/cm3Native BaP Standard 4 0.500 g/cm3Native BaP Standard 3 0.200 g/cm3Native BaP Standard 2 0.05
