ASTM C895-1987(2003) Standard Test Method for Lead and Cadmium Extracted from Glazed Ceramic Tile《从上釉瓷砖提取铅和镉的试验方法》.pdf

1、Designation: C 895 87 (Reapproved 2003)Standard Test Method forLead and Cadmium Extracted from Glazed Ceramic Tile1This standard is issued under the fixed designation C 895; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year

2、of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the precise determination oflead and cadmium extracted by acetic acid from glazed ceramict

3、ile that are intended for use in areas of food preparation. Theprocedure of extraction may be expected to accelerate therelease of lead from the glaze and to serve, therefore, as asevere test that is unlikely to be matched under the actualconditions of usage of such ceramic tile. This test method is

4、specific for lead and cadmium.1.2 The values stated in inch-pound units are to be regardedas the standard. The values given in parentheses are forinformation only.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the

5、user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:C 738 Test Method for Lead and Cadmium Extracted fromGlazed Ceramic Surfaces2C 1034 Test Method for Lead and C

6、admium Extracted fromGlazed Ceramic Cookware3C 1035 Specification for Lead and Cadmium Extractedfrom Glazed Ceramic Cookware33. Summary of Test Method3.1 The lead and cadmium extracted from the article undertest, by acetic acid at 20 to 24C (68 to 75F) after 24 h ofleaching, are measured by atomic a

7、bsorption spectrophotom-etry using specific hollow-cathode lamps for lead and cad-mium, respectively.4. Significance and Use4.1 There are several test methods available to measure thelead and cadmium release from dinnerware and cookware (seeTest Methods C 738 and C 1034 and Specification C 1035).The

8、se standards are used as a control to ensure the protectionof the population against a possible health hazard.4Thispotential hazard arises with improperly formulated, applied,fired glazes and decorations. This test method deals specificallywith ceramic tile that are intended to come in contact with

9、foodduring its preparation (for example, counter top tile).5. Interferences5.1 Since specific hollow-cathode lamps for lead and cad-mium are used, there are no interferences.6. Apparatus6.1 Atomic Absorption Spectrophotometer, equipped with a4-in. (102-mm) single slot or Boling burner head and digit

10、alconcentration readout attachment (DCR) if available.5Thisinstrument should have a sensitivity of about 0.5 ppm of leadfor 1 % absorption and a sensitivity of about 0.25 ppm ofcadmium for 1 % absorption. Use the operating conditions asspecified in the instrument manufacturers analytical methodsmanu

11、al.NOTE 11 ppm = 1 mg/L or one part per million is one milligram perlitre.6.2 Hollow-Cathode Lead Lamp, with wavelength set at283.3 or 217.0 nm.6.3 Hollow-Cathode Cadmium Lamp, with wavelength setat 228.8 nm.6.4 Glassware of chemically resistant borosilicate glass tomake reagents and solutions.6.5 T

12、est CellChemically resistant borosilicate glass cylin-der to contain the leaching solution. An open-ended cellapproximately 80 mm in length and 60 mm in internal diameterhas proven suitable.1This test method is under the jurisdiction of ASTM Committee C21 on CeramicWhitewares and Related Products an

13、d is the direct responsibility of SubcommitteeC21.06 on Ceramic Tile.Current edition approved Oct. 1, 2003. Published October 2003. Originallyapproved in 1978. Last previous edition approved in 1998 as C 895 87 (1998).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact AS

14、TM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.4“Lead Industries, Inc.,” Proceedings, International Conference on CeramicFoodware Safety, 1975, pp. 817.5PerkinElmer Model 303 and

15、JarrellAsh Model 82546 have been foundsuitable for this determination. Other makes of atomic absorption spectrophotom-eters having comparable sensitivity and accuracy and with background correctionare also suitable.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken,

16、 PA 19428-2959, United States.7. Reagents7.1 Purity of ReagentsReagent grade chemicals shall beused in all tests. Unless otherwise indicated, it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents of the American Chemical Societywhere such specif

17、ications are available.6Other grades may beused provided it is first ascertained that the reagent is ofsufficiently high purity to permit its use without lessening theaccuracy of the determination.7.2 Purity of WaterUnless otherwise indicated, referencesto water shall be understood to mean distilled

18、 water.7.3 Acetic Acid (4 % by Volume)Mix 1 volume of glacialacetic acid with 24 volumes of water. Run a reagent blank eachtime a 4 % acetic acid solution is prepared.7.4 Detergent RinseAdd 15 g of suitable alkaline deter-gent7to 1 gal (3.79 L) of lukewarm tap water.7.5 Lead Nitrate Solution (1000-p

19、pm Pb)Dissolve 1.598g of lead nitrate (Pb(No3)2) in 4 % acetic acid and dilute to 1L with 4 % acetic acid. Commercially available standard leadsolutions may also be used.7.6 Hydrochloric Acid (1 % by Weight)Mix 1 volume ofconcentrated hydrochloric acid (HCl, sp. gr. 1.19) with 37volumes of water.7.7

20、 Cadmium Solution (1000-ppm Cd)Dissolve 0.9273 gof anhydrous cadmium sulfate in approximately 250 mL of 1 %HCl (see 7.6), and dilute to 500 mL with 1 % HCl. Commer-cially available standard cadmium solutions may also be used.8. Procedure8.1 Preparation of SampleTake, at random, six identicaltiles an

21、d cleanse the surface of each with a detergent rinse.Then rinse with tap water, followed by distilled water, and dry.Using a suitable silicone rubber sealant free of lead andcadmium,8seal the test cell to the glazed surface. Fill each cellwith sufficient 4 % acetic acid to achieve a ratio of 25 mL o

22、fsolution to each 1 in.2(6.45 cm2) of exposed glaze surface.Record the volume of acid used in each cell. If the tile beingtested has a surface dimension less than 60 mm (smaller thanthe diameter of the test cell), a suitable number of tiles shall bemounted and grouted9to provide the required test ar

23、ea.Mounting, grouting, and grout cleanup should precede thedetergent rinse. Each mounted set constitutes one test sample.Cover each test with a glass plate to prevent evaporation ofsolution, avoiding contact between cover and surface ofleaching solution. The extraction shall be run in total darkness

24、,and the test array must be covered with an opaque cloth or foilto prevent exposure to light. Let stand for 24 h at 20 to 24C(68 to 74F).8.2 Preparation of Standards:8.2.1 Lead StandardsDilute lead nitrate solution (see 7.5)with acetic acid (see 7.3) to obtain working standards havingfinal concentra

25、tions of 0, 5, 10, 15, and 20 ppm of Pb.8.2.2 Cadmium StandardsDilute cadmium stock solution(see 7.7) with acetic acid (see 7.3) to obtain working standardshaving final concentrations of 0.0, 0.3, 0.5, 1, 1.5, and 2.0 ppmof Cd.8.3 Determination of Lead by Atomic AbsorptionStir thesample (leaching) s

26、olution and pour off a portion into a cleanflask. Using the atomic absorption spectrophotometer (see 6.1)and hollow-cathode lamp (see 6.2), at the same time determinethe absorption of the lead working standards (see 8.2.1) andsample (leaching) solutions, diluting the latter with 4 % aceticacid if re

27、quired (if solution contains over 20 ppm). Concentratesamples containing less than 1 ppm of lead by accuratelytransferring a minimum of 50.0 mL of solution to a 250-mLbeaker and evaporating to dryness on a steam bath. Dissolvethe residue in 4 % acetic acid by adding exactly 0.1 of thevolume of the s

28、olution taken for concentration, cover withwatch glass, and swirl to complete dissolution. Prepare astandard curve of absorption versus concentration (ppm).Determine the lead content (ppm Pb) of sample (leaching)solution from the standard curve. If digital concentrationreadout is used, the standard

29、curve is not necessary. However,standards bracketing the solution under test should be used.8.4 Determination of Cadmium by Atomic AbsorptionSpectrophotometryProceed as in 8.3 using the cadmiumhollow-cathode lamp (see 6.3) and cadmium standards (see8.2.2). If the sample (leaching) solutions contain

30、more than 2ppm of Cd, dilute with 4 % acetic acid. Concentrate samplescontaining less than 0.1 ppm as in 8.3.9. Report9.1 Report the type of tile tested, the volume of acid used,the test cell area, and the lead and cadmium leached in parts permillion for each tile or sample mount tested.9.2 As indic

31、ated in Section 1, this procedure covers theextraction and measurement of lead and cadmium. It is generalin that it does not recommend specific sample types. Forspecial end uses, as for example, process control or interlabo-ratory testing, a specific size and type of sample unit should beused.10. Pr

32、ecision and Bias10.1 In an analysis of variance study from eight laborato-ries, the standard deviation between laboratories was 0.06mg/L for lead and 0.007 mg/L for cadmium. The within-laboratory precision had a standard deviation of 0.04 mg/L forlead and 0.004 mg/L for cadmium. The standard deviati

33、on forinteraction between laboratories and samples is 0.06 mg/L forlead and 0.010 mg/L for cadmium. Reproducibility is definedas the square root of the sum of the three component variances.The reproducibilities were 0.10 mg/L for lead and 0.013 mg/Lfor cadium.6Reagent Chemicals, American Chemical So

34、ciety Specifications, AmericanChemical Society, Washington, DC. For suggestions on the testing of reagents notlisted by the American Chemical Society, see Analar Standards for LaboratoryChemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeiaand National Formulary, U.S. Pharmacop

35、eial Convention, Inc. (USPC), Rockville,MD.7A suitable detergent is Calgonite, manufactured by the Calgon Corp., Box1436, Pittsburgh, PA 15230, and available in most supermarkets.8A suitable sealant is Dow Corning No. 784 Interior Sealant, manufactured byDow Corning Corp., Midland, MI 48640.9To ensu

36、re no loss of solution, a silicone rubber, as described, may be used forgrouting. Care should be taken to minimize the amount of grout on the glaze surface.C 895 87 (2003)210.2 The bias of this test method is further limited by theability to obtain representative samples of the statistical uni-verse

37、 being sampled.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of s

38、uch rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for add

39、itional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to t

40、he ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).C 895 87 (2003)3