BS EN ISO 22155:2016 download free.Soil quality — Gas chromatographic determination of volatile aromatic and halogenated hydrocarbons and selected ethers — Static headspace method.
BS EN ISO 22155 specifies a static headspace method tor quantitative gas chromatographic determination of volatile aromatic and halogenated hydrocarbons and selected aliphatic ethers in soil. BS EN ISO 22155 is applicable to all types of soil.
The limit of quantification is dependent on the detection system used and the quality of the methanol grade used for the extraction of the soil sample.
Under the conditions specified in BS EN ISO 22155, the following limits of quantifications apply (expressed on basis of dry matter).
Typical limit of quantificatIon when using GC-FID:
— volatile aromatic hydrocarbons: 0,2 mg/kg:
— aliphatic ethers as methyl tert.-butyl ether(MTBE) and tert.-amyl methyl ether (TAME): 0,5 mg/kg.
Typical limit of quantification when using GC-ECD:
— volatile halogenated hydrocarbons: 0,01 mg/kg to 0,2 mg/kg.
Lower limits olquantilicatlon for some compounds can be achieved by using mass spectrometry (MS)
with selected Ion detection (see Annex 0).
2 NormatIve references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 10381-1, Soil quality — Sampling — Part 1: Guidance on the design of sampling programmes ISO 10381.2, SoIl quality — Sampling — Part 2: Guidance on sampling techniques
ISO 11465, Soil quality — Determination of dry matter and water content an a mass basis — Gravimetric method
ISO 15680, Water quality — Gas-chromatographic determination cif a number of monocyclic aromatic hydrocarbons. naplithalene and several chlorinated compounds using purge-and-trap and thermal desorptlon
ISO 18512. Soil quality — Guidance at long and short term storage of soil samples
ISO 22892, Soil quality — Guidelines fi,r the identification of target compounds by gas chromatography and mass spectrontetry
4.7 Standard solutions
4.7.1 Standard stock solutions for the volatile compounds in methanol
Prepare the stock solutions by adding delined amounts (e.g. 100 l) of each standard compound (4… 4,4 and 4.5) with a microlitre syringe (5.8). Immerse the tip of the needle in the solvent methanol and weigh with an accuracy of 0,1 mg.
NOTE 1 A convenient concentration (4 mg/mI) of the standard stock solution is obtained by weighing 100 nig of the standard substance and dissolving it in 25 ml of the solvent. The stock solution is stable for about 6 m when stored at —18 C.
NOTE 2 For practical reasons, mixed standard stock solutions can also be prepared.
4.72 Internal standard stock solutions In methanol
The containers containing the solutions shall be weighed so that any evaporation losses of the solvent may be recognized. The solutions shall be stored at a temperature of (4 ± 2) C In the dark. Prior to use, they shall be brought to ambient temperature.
Prepare the internal standard stock solutions with the individual internal standard compounds (4.2.1 and 4.22) in the same procedure as in 4.11.
4.7.3 Intermediate mixed standard solutions
Prepare intermediate mixed standard solutions by mixing a defined volume of each individual standard stock solution or a mixed standard stock solution and dilute with methanol.
NOTE A typical concentration 1s40 g/.nl.
Store the Intermediate mixed standard solutions at (4 ± 2) °C not longer than 3 rn
4.7.4 WorkIng standard solutions
Prepare at least live different concentrations (e.g from 0,2 pg/mI to 3.2 pg/mI) by suitable dilutions of the Intermediate mixed standard solutions adding SOpI to 500 p1 014.7,3 to methanol (10 ml) using a micrulitre syringe (5).
4.7.5 WorkIng internal standard solutions
Prepare the Internal standard solutions of defined concentration (e.g. 0.4 pg/mI) as described In 4.2.3..
4.7.6 Aqueous calibration standard solutions
Prepare the calibration solutions (see Tblr 7) by adding a defined amount (e.g. 50 p1) of working standard solutions and internal standard solutions to a defined volume (e.g. 10 ml) of water in an appropriate headspace vial. Use a syringe and immerse the top of the needle in the water. Seal the vial tightly with a crimp cap fitted with polytetralluoroethylene (PTFE) coated septum. The total volume of the methanol used for calibration shall be the same which will be taken for the methanol extract of the soil sample (see 13). Make sure that the content of the organic solvent in the final aqueous calibration standard solution does not exceed the volume fraction of 2 %.
5.6 Gas diromatograph, equipped with one or two appropriate detectors. Detectors like flame ionization detector (FID), electron capture detector (ECD). photo Ionization detector (PID) or electrolytic conductivity detector (ELCD) and mass spectrometer (MS) can be used, depending on the substances to be analysed and their target level of contamination. The mass spectrometer should be able of operating over the total mass range of interest and being equipped with a data system capable of quantifying ions using selected rn/z values.
5.7 Electronic integrator or computer wIth chromatographlc software.
5.8 Syringe, volumeS uI. 10 p1. 50 p1. 100 pl.250 ill, and 500 p1.
5.9 Centrifuge, with a capacity of a rotation frequency that results into a radial acceleration of at
least 200(g.
6 Sampling, preservation, and sample pretreatment
6.1 General
Sampling shall be carried out according to ISO 10381-I using equipment according to ISO 10381-2 after coordination with the analytical laboratory.
Samples shall be stored cool according to ISO 18512 (2°C to 8 ‘C). Samples are not pretreated. Exposure of samples to air, even during sampling, shall be avoided as far as possible.
Sampling for volatile compounds can be carried out with several techniques. It is strongly recommended to use one of the following procedures described in 6.2 and 62 in order to prevent losses by volatilization.
Determine the dry matter content of the Field moist sample according to ISO 11465. In case the sampling method in 62 Is used, a separate sample should be delivered to the laboratory for determination of the dry matter.
6.2 Sampling using vials pre-filled with methanol
Transfer a defined volume of soil using an appropriate device into a preweighed vial which Is filled with a defined volume of methanol already containing internal standards (4.8). Prevent leakages by cleaning the top of the vessel before sealing.
The soil samples should be taken from undisturbed material using an appropriate sample cutter of known volume. e.g. a modified 20 ml disposable plastic syringe with the tip cut off. The soil sample should be collected immediately after exposing a fresh soil surface of the drilling core, e.g. of an open window sampler or the trial pit wall. The incorporation of material like roots or stones should be avoided as far as possible.
Make sure that the sample is completely covered with methanol containing Internal standards (4,8). Then close the cap of the PTFE coated septum. At least one blank sample on every site shall be prepared in the field by opening the prepared vial for the same time period as necessary for the filling with soil sample. Add methanol containing internal standards (4.8) and close the cap of the vial. If blank values are unusually high (more than 58 % of the lowest value of interest) the reason for these high blanks shall be investigated.
The sampling vials should be kept dark In a cooler (before and after sampling) throughout the whole transportation. For details, see ISO 18512.
NOTE The procedure described here assumes that methanol containing internal standards Is used. It is also acceptable that the internal standards are added in the methanol In the laboratory at the start of the extraction procedure.