DIN ISO 28540-2014 Water quality - Determination of 16 polycyclic aromatic hydrocarbons (PAH) in water - Method using gas chromatography with mass spectrometric detection (GC-MS) (.pdf

1、May 2014 Translation by DIN-Sprachendienst.English price group 15No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 13

2、.060.50!%1K“2149940www.din.deDDIN ISO 28540Water quality Determination of 16 polycyclic aromatic hydrocarbons (PAH) in water Method using gas chromatography with mass spectrometric detection(GC-MS) (ISO 28540:2011),English translation of DIN ISO 28540:2014-05Wasserbeschaffenheit Bestimmung von 16 po

3、lycyclischen aromatischen Kohlenwasserstoffen (PAK) in Wasser Verfahren mittels Gaschromatographie und massenspektrometrischer Detektion (GC-MS)(ISO 28540:2011),Englische bersetzung von DIN ISO 28540:2014-05Qualit de leau Dtermination de 16 hydrocarbures aromatiques polycycliques (HAP) dans leau Mth

4、ode par chromatographie en phase gazeuse avec dtection par spectromtrie demasse (CG-SM) (ISO 28540:2011),Traduction anglaise de DIN ISO 28540:2014-05www.beuth.deDocument comprises 34 pagesIn case of doubt, the German-language original shall be considered authoritative.05.14 Contents PageNational for

5、eword . 3 Introduction . 7 1 Scope 8 2 Normative references 8 3 Terms and definitions . 8 4 Principle . 9 5 Interferences 11 6 Reagents 11 7 Apparatus . 14 8 Sampling 15 9 Procedure . 15 10 Calibration 18 11 Measurement of samples 19 12 Identification 19 13 Calculation . 21 14 Expression of results

6、23 15 Test report 24 Annex A (informative) Examples for GC-MS conditions . 25 Annex B (informative) Precision and accuracy 26 Annex C (informative) Examples of the construction of special apparatus . 29 Annex D (informative) Example of chromatograms 31 Annex E (informative) Extraction with extractio

7、n disks 33 Bibliography 34 DIN ISO 28540:2014-05 2National Annex NA (informative) Bibliography 5 A comma is used as the decimal marker. National foreword This document (ISO 28540:2011) has been prepared by Technical Committee ISO/TC 147 “Water quality” (Secretariat: DIN, Germany). The responsible Ge

8、rman body involved in its preparation was the Normenausschuss Wasserwesen (Water Practice Standards Committee), Working Committee NA 119-01-03-02 UA Organische Verbindungen of NA 119-01-03 AA Wasseruntersuchung. Designation of the method: Determination of 16 polycyclic aromatic hydrocarbons (PAH) in

9、 water Method using gas chromatography with mass spectrometric detection (GC-MS) (F 40): Method DIN ISO 28540 F 40 The following changes have been made to the ISO Standard as regards application in Germany: In Clause 4, NOTE 2, reference is made to the procedure described in ISO 17858:2007. This pro

10、cedure is correct as regards the spiking and extraction of samples containing suspended solids. However, washing should not be carried out with acids and/or bases. This makes lower results possible. In Subclause 13.3, third paragraph, the English term used in the ISO Standard is “diluted”. The corre

11、ct term here is “spiked”, and the translation of “spiked”, “aufgestockt”, is used in the German version of the present standard. In Clause 14, the rounded result for 0,008 5 g/l - which is incorrectly given in the original ISO Standard as 0,008 g/l - has been corrected both in the German and corresp

12、ondingly in the English version of DIN ISO 28540 to 0,009 g/l. The DIN Standards corresponding to the International Standards referred to in this document are as follows: ISO 1042 DIN EN ISO 1042 ISO 4800 DIN ISO 4800 ISO 5667-1 DIN EN ISO 5667-1 ISO 5667-3 DIN EN ISO 5667-3 ISO 7981-1 DIN 38407-7 I

13、SO 7981-2 DIN 38407-8 ISO 8466-1 DIN 38402-51 ISO 15089 DIN ISO 15089 ISO 17993 DIN EN ISO 17993 ISO 22892 DIN EN ISO 22892 DIN ISO 28540:2014-05 3Expert assistance and specialized laboratories will be required to perform the analyses described in this standard. Existing safety requirements are to b

14、e observed. Depending on the objective of the analysis, a check shall be made on a case-by-case basis as to whether and to what extent additional conditions will have to be specified. This standard has been prepared by the Normenausschuss Wasserwesen (Water Practice Standards Committee) in collabora

15、tion with the Wasserchemische Gesellschaft - Fachgruppe in der Gesellschaft Deutscher Chemiker (Water Chemistry Society - Division of the German Chemical Society). It is part of the series Deutsche Einheitsverfahren zur Wasser-, Abwasser- und Schlammuntersuchung (German standard methods for the exam

16、ination of water, waste water and sludge): Determination of 16 polycyclic aromatic hydrocarbons (PAH) in water Method using gas chromatography with mass spectrometric detection (GC-MS) (F 40). Standard methods published as DIN Standards are obtainable from Beuth Verlag GmbH, either individually or g

17、rouped in volumes. The standard methods included in the loose-leaf publication entitled Deutsche Einheitsverfahren zur Wasser-, Abwasser- und Schlammuntersuchung will continue to be published by Wiley-VCH Verlag GmbH used only to check that resolution is sufficient. DIN ISO 28540:2014-05 136.8 Calib

18、ration solutions. Prepare at least five calibration solutions by appropriate dilution of the multiple substance stock solution (6.7), using hexane (6.2.1) or acetonitrile (6.2.2) as solvent. Add to each solution the same amount of the stock solution of the injection standard to give a final concentr

19、ation of 100 ng/ml. It is recommended that the solvent for the calibration solutions be the same as the solution of the final extract. Transfer, for example, 50 l of the multiple stock solution into a 5 ml one-mark volumetric flask (7.14) and make up to the mark an with appropriate solvent. A volume

20、 of 1 l of this reference solution contains 100 pg of the respective individual substances ( 100 ng/ml). The mass concentration of the PAH in the multiple substance stock solution shall be checked by comparison with an independent, preferably certified, standard solution. All individual substances s

21、hall agree within 10 %. These solutions shall be used for the calibration of the gas chromatographic system (mixture in hexane) as well as for the addition of internal standards mixture in acetonitrile (6.2.2.). 7 Apparatus Usual laboratory equipment and in particular the following. Clean laboratory

22、 glassware to eliminate all interferences. NOTE All glassware can be cleaned, for example, by rinsing with detergent and hot water, and drying for about 15 min to 30 min at about 120 C. After cooling, the glassware can be rinsed with acetone (6.2.3), sealed, and stored in a clean environment. For dr

23、inking water analysis, do not re-use glassware that has been in contact with waste water samples or samples with high PAH concentrations. 7.1 Coloured or clear glass bottles, narrow-necked, flat-bottomed, 1 000 ml, with aluminium-lined cap. 7.2 Magnetic stirrer, with stirring bars (size approximatel

24、y 20 mm), glass, kept under the solvent used for extraction. 7.3 Separating funnel, capacity 1 000 ml, ISO 48002, with PTFE stopcock and glass stopper. 7.4 Conical flask, nominal capacity 250 ml, with glass stopper. 7.5 Equipment for concentrating the eluates by evaporation, e.g. a rotary evaporator

25、, regulatable for constant vacuum and with a temperature-controlled water bath, or stripping equipment using nitrogen gas. 7.6 Microlitre syringes, e.g. 500 l and 1 000 l. 7.7 Reduction flask, 100 ml (e.g. as shown in Figure C.3). 7.8 Centrifuge with rotor, with centrifuge tubes (e.g. as shown in Fi

26、gure C.2) with tapered bottom, 50 ml. 7.9 Shaking apparatus, with adjustable rotational speed. 7.10 Glass autosampler vials, capacity e.g. 2 ml, with inert cap and PTFE-coated septum. 7.11 Glass vials, e.g. centrifuge tubes, graduated (scale division 0,1 ml), nominal capacity 10 ml, with glass stopp

27、ers. 7.12 Gas chromatograph, with mass spectrometric detector (EI). 7.13 High resolution, low bleeding capillary column for gas chromatography (e.g. see Annex A). DIN ISO 28540:2014-05 147.14 One-mark volumetric flasks, ISO 10421, class A. 7.15 Microfilter, with solvent-resistant hydrophilic membran

28、e, pore size 0,45 m. 7.16 Pasteur pipettes. 7.17 Glass cartridges, filled with at least 0,5 g silica (see 7.18). NOTE These cartridges are commercially available. 7.18 Silica, average particle size approximately 40 m, heated at 450 C for 3 h and stored in a desiccator to ensure maximum activity. NOT

29、E Pre-packed silica cartridges are commercially available. 7.19 Molecular sieve beads, pore diameter 0,4 nm. 7.20 Glass wool. 8 Sampling Collect the sample in a glass bottle with a volume of 1 000 ml (7.1). Dechlorinate water samples containing chlorine by adding approximately 80 mg of sodium thiosu

30、lfate (6.1) prior to sample collection. When sampling drinking water from a tap of the water supply, collect the sample before the tap is sterilized for bacteriological sampling by flame treatment. NOTE Guidance on sampling programmes can be found in ISO 5667-1. Fill the bottle to the shoulder (appr

31、oximately 950 ml). Determine the volume of the sample to be extracted by weighing, before extraction and after emptying, with an accuracy of 5 g. Store the sample between (3 2) C, protected from light, until the extraction is carried out (see also ISO 5667-3). Ensure that the extraction is carried o

32、ut within the maximum preservation time, as specified in ISO 5667-3, to avoid losses. It is generally recommended that the extraction be carried out as soon as practicable to minimize potential adherence to glass which could be an issue when glassware is reused. 9 Procedure 9.1 General consideration

33、s The extraction method shall not be used with samples containing more than 150 mg/l of suspended matter. Volatile solvents other than hexane may be used if it is proven that there is equal or better recovery (recovery mass fraction between 70 % and 110 %). 9.2 Extraction 9.2.1 Sample preparation an

34、d extraction Add a precisely defined amount of the internal standard (e.g a volume containing 50 ng), dissolved in a water-soluble solution (6.5.1). Add 25 ml of hexane (6.2.1), add a stirring bar (7.2) and close the flask (7.1) with an aluminium-lined cap or close the conical flask (7.4) with a gro

35、und stopper. Thoroughly mix the sample using the magnetic stirrer at maximum setting during 60 min. Transfer the sample to a separating funnel and allow the phases to separate for at least 5 min. If an emulsion is formed during the extraction process, collect DIN ISO 28540:2014-05 15it in a centrifu

36、ge tube and centrifuge (7.8), for example for 10 min at about 3 000 r/min. Alternatively, a microseparator (see Annex B) can be used for separation of phases. Remove the separated water with a Pasteur pipette (7.16). Transfer the extract to a conical flask (7.4) and dry it according to 9.2.2. Be sur

37、e to rinse the bottle thoroughly with extraction solvent to extract any adsorbed PAH. NOTE The extraction procedure can also be carried out in a separating funnel (7.3) using a shaking apparatus (7.9) and a microseparator (Annex C). For the extraction of water samples with high concentrations of PAH

38、, transfer only 10 ml to 100 ml of the homogeneous sample to a 250 ml conical flask (7.4) with a pipette and dilute with water to 200 ml. After adding 25 ml of hexane (6.2.1), proceed as above. 9.2.2 Drying of the extract Transfer the hexane layer obtained in 9.2.1 into a 100 ml conical flask. Rinse

39、 the funnel or centrifuge tube with 5 ml of hexane and add it to the total extract. Dry the extract with approximately 0,2 g sodium sulfate for at least 15 min, swirling the vessel frequently. Decant the dry extract into a reduction flask (7.7). Rinse the conical flask twice with 5 ml of hexane and

40、decant this also into the reduction flask. 9.2.3 Enrichment Evaporate the dried hexane extract obtained in 9.2.2 until it fills only the tapered tip of the reduction flask (approximately 2 ml), e.g. using a rotary evaporator, at a temperature of 30 C, slowly lowering the pressure to 20 kPa. Do not e

41、vaporate the extracts to dryness, as losses of the 2- or 3-ring compounds can occur. Adding a few drops of decane (6.2.4) or isooctane (6.2.5) reduces the loss of the most volatile compounds. Dissolve the extract into a known volume (e.g. 2 ml). Be sure that any residues that may be deposited on the

42、 glass wall are dissolved by shaking the extract using the shaking apparatus. Clean the extracts of samples of unknown origin by silica clean-up according to 9.2.4 if the chromatogram shows interferences that hamper the quantification. Transfer the enriched sample, if necessary after filtration thro

43、ugh a microfilter (7.15), into a glass sample vial. Keep the sample in a cool and dark place until the analysis is carried out. Proceed as specified in 9.4. Alternative enrichment methods may be used. If a large volume injection is used or if higher concentrations of the target compounds are expecte

44、d, a lower enrichment factor may be used. 9.2.4 Silica clean-up For clean-up of the extract, use columns Pasteur pipettes (7.16) with a glass wool (7.20) plug or a cartridge (7.17) containing at least 0,5 g of silica (7.18). Clean the silica in the column or in the cartridge by rinsing with five bed

45、 volumes of a mixture of dichloromethane and hexane (11), followed by conditioning with the same volume of hexane (6.2.1). NOTE 1 The clean-up is not possible for solutions that contain acetone. Dry the solvents used for cleaning the extract by applying molecular sieve beads (7.19). The silica shoul

46、d have its maximum activity. Concentrate the enriched extract (9.2.3) by blowing with a gentle stream of nitrogen (6.4.1), so that a volume of 500 l remains. DIN ISO 28540:2014-05 16Transfer the concentrated extract using a Pasteur pipette (7.16) on to the hexane-covered silica and allow to soak alm

47、ost completely into the silica. Collect the eluate in a glass vial (7.11). Rinse the reduction flask with 500 l of hexane (6.2.1), add this solution on to the column, and allow to soak almost completely into the silica. Elute the PAH with a mixture of dichloromethane and hexane (11). NOTE 2 Commerci

48、ally available cartridges containing 0,5 g of silica require a volume of at least 3 ml of the dichloromethane-hexane (11) mixture for the elution of the PAH. Add a few drops of decane (6.2.4) or isooctane (6.2.5) to the eluate, homogenize by shaking, and enrich (see 9.2.3) to between 200 l and 250 l, e.g. first with a rotary evaporator (7.5) to about 2 ml, then with a stream of nitrogen (6.4.1). Fill the extract up to a known volume (e.g. 2 ml) with the same solvent that has been used for the preparation of the