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HJ 952-2018 English PDF

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HJ 952-2018: Soil and sediment - Determination of polybrominated diphenyl ethers - Gas chromatography mass spectrometry
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Basic data

Standard ID	HJ 952-2018 (HJ952-2018)
Description (Translated English)	Soil and sediment - Determination of polybrominated diphenyl ethers - Gas chromatography mass spectrometry
Sector / Industry	Environmental Protection Industry Standard
Classification of Chinese Standard	Z18
Word Count Estimation	19,177
Date of Issue	2018-07-29
Date of Implementation	2018-12-01
Regulation (derived from)	Ministry of Ecology and Environment Announcement No. 21 of 2018
Issuing agency(ies)	Ministry of Ecology and Environment

HJ 952-2018: Soil and sediment - Determination of polybrominated diphenyl ethers - Gas chromatography mass spectrometry

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Soil and sediment - Determination of polybrominated diphenyl ethers - Gas chromatography mass spectrometry National Environmental Protection Standard of the People's Republic Determination of soil and sediment polybrominated diphenyl ethers Gas chromatography-mass spectrometry Soil and sediment-Determination of polybrominated diphenyl ethers -Gas chromatography mass spectrometry Published on.2018-07-29 2018-12-01 Implementation Ministry of Ecology and Environment released i directory Foreword.ii 1 Scope..1 2 Normative references..1 3 method principle..1 4 Reagents and materials.1 5 instruments and equipment.3 6 samples.4 7 Analysis steps..6 8 Results calculation and representation..7 9 Precision and Accuracy..9 10 Quality Assurance and Quality Control..10 11 Notes.10 12 Waste treatment.11 Appendix A (Normative) Method Detection Limit and Lower Limit of Measurement 12 Appendix B (informative) Mass Spectrometry Reference Conditions.13 Appendix C (informative) Precision and accuracy of the method 14

Foreword

To implement the Environmental Protection Law of the People's Republic of China, protect the environment, protect human health, and regulate soil and sediment This standard is developed for the determination of polybrominated diphenyl ether. This standard specifies gas chromatography-mass spectrometry for the determination of polybrominated diphenyl ethers in soils and sediments. Appendix A of this standard is a normative appendix, and Appendix B and Appendix C are informative appendices. This standard is the first release. This standard is formulated by the Environmental Monitoring Department of the Ministry of Ecology and Environment and the Science and Technology Standards Department. This standard was drafted. National Environmental Analysis and Testing Center, Environmental Protection External Cooperation Center of the Ministry of Ecology and Environment. This standard is verified by. Hubei Environmental Monitoring Center Station, Guangdong Environmental Monitoring Center, Zhejiang Environmental Monitoring Center, Ningbo Guoke Monitoring Technology Co., Ltd., China National Academy of Environmental Sciences, State Key Laboratory of Environmental Benchmarks and Risk Assessment, and Island Tianjin Enterprise Management (China) Co., Ltd. Beijing Analysis Center. This standard is approved by the Ministry of Ecology and Environment on July 29,.2018. This standard has been implemented since December 1,.2018. This standard is explained by the Ministry of Ecology and Environment. 1 Determination of soil and sediment PBDEs by gas chromatography-mass spectrometry Warning. The organic solvents and reference materials used in the experiment are toxic and hazardous substances, standard solution preparation and sample preparation. The process should be carried out in a fume hood; protective equipment should be worn as required to avoid direct contact with skin and clothing.

1 Scope of application

This standard specifies gas chromatography-mass spectrometry for the determination of polybrominated diphenyl ethers in soils and sediments. This standard applies to the determination of eight PBDE congeners in soils and sediments. When the sample volume is 10.0 g and the volume is 1.0 ml, the method for determining the tris-heptabromodiphenyl ether determined by this standard is detected. The limit is 0.1~0.2g/kg, the lower limit of determination is 0.4~0.8g/kg; the detection limit of decabromodiphenyl ether is 2.7g/kg, The lower limit is 10.8 g/kg. See Appendix A for details.

2 Normative references

This standard refers to the following documents or their terms. For undated references, the valid version applies to this standard. GB 17378.3 Marine monitoring specification Part 3. Sample collection, storage and transport GB 17378.5 Marine monitoring specification Part 5. Sediment analysis HJ 494 Water Quality Sampling Technical Guidance HJ 613 Determination of dry matter and moisture in soils - Gravimetric method HJ/T 166 Technical Specifications for Soil Environmental Monitoring

3 Principle of the method

Extracting PBDE from soil or sediment by pressurized fluid extraction or Soxhlet extraction, the extract is purified, After concentration and constant volume, it was separated by gas chromatography and detected by mass spectrometry. Qualitative according to retention time, fragment ion mass-to-charge ratio and abundance ratio, Quantitative isotope dilution method using selective ion detection.

4 reagents and materials

Analytically pure reagents that meet national standards are used for analysis, unless otherwise stated. water. 4.1 Dichloromethane (CH2Cl2). pesticide residue grade. 4.2 Hexane (C6H14). pesticide residue grade. 4.3 Methanol (CH3OH). pesticide residue grade. 4.4 Acetone (CH3COCH3). pesticide residue grade. 4.5 Sodium hydroxide (NaOH). excellent grade. 4.6 Sulfuric acid. ρ(H2SO4) = 1.84 g/ml. 24.7 Nitric acid. ρ(HNO3) = 1.42 g/ml. 4.8 Nitric acid solution. 19. 4.9 Sodium hydroxide solution. ρ (NaOH) = 50 g/L. Dissolve 50 g of sodium hydroxide (4.5) in a small amount of water and dilute to 1 L. 4.10 Standard stock solution of polybrominated diphenyl ether. ρ=20.0 mg/L, including BDE-28, BDE-47, BDE-99, BDE-100, BDE-153, BDE-154 and BDE-183; wherein the concentration of BDE-209 is.200 mg/L. Using decane as a solvent Standard substance preparation. You can also purchase a commercially available certified standard solution directly. For the storage time, please refer to the relevant instructions of the standard solution certificate. 4.11 Polybromodiphenyl ether solution. ρ = 2.00 mg/L, of which BDE-209 concentration is 20.0 mg/L. Pipette 100 μl of the standard stock solution of PBDE (4.10) into a 1.5 ml injection vial and add 900 μl of n-hexane (4.2). Mix well. Available now. 4.12 Carbon-labeled PBDE standard solution (extract internal standard). ρ=2.00 mg/L, including 13C-BDE-28, 13C-BDE-47, 13C-BDE-99, 13C-BDE-100, 13C-BDE-153, 13C-BDE-154 and 13C-BDE-183; among them, 13C-BDE-209 The concentration was 20.0 mg/L. The solvent is decane, a commercially available certified standard solution. 4.13 Carbon Labeling PCB-209 Standard stock solution. ρ=50.0 mg/L, solvent is decane, commercially available certified standard solution. 4.14 Carbon Label PCB-209 Use Solution (Injection Internal Standard). ρ = 5.00 mg/L. Pipette 1.00 ml of carbon-labeled PCB-209 standard stock solution (4.13) into a 10 ml volumetric flask with n-hexane (4.2) Make up to the mark and mix. Store under 4 °C for 3 months. 4.15 4,4'-DDT (p, p'-DDT) standard stock solution. ρ = 100 mg/L, the solvent is methanol, commercially available certified standard solution. 4.16 4,4'-DDT standard use solution. ρ=5.00 mg/L. Pipette 50 μl of p,p'-DDT standard stock solution (4.15) into a 1.5 ml sample vial and add 950 μl of n-hexane (4.2). Mix well. Available now. 4.17 Decafluorotriphenylphosphine (DFTPP) standard stock solution. ρ=1000 mg/L, solvent is methanol, commercially available certified standard liquid. 4.18 Standard use solution of decafluorotriphenylphosphine. ρ=50.0 mg/L. Pipette 50 μl of decafluorotriphenylphosphine standard stock solution (4.17) into a 1.5 ml sample vial and add 950 μl of n-hexane (4.2). Mix well. Available now. 4.19 anhydrous sodium sulfate (Na2SO4). excellent grade pure. It was fired in a muffle furnace at 450 ° C for 4 h, cooled to room temperature, placed in a ground glass bottle, and stored in a desiccator. 4.20 Silica gel. 75 ~ 180 μm (200 ~ 80 mesh). A certain amount of silica gel is placed in a beaker, and an appropriate amount of methanol (4.3) is added to make the liquid surface higher than the silica gel layer by 1 to 2 cm. After stirring for 1 ~ 2 min, the methanol was discarded. Repeat this step 2 times, continue to clean twice with dichloromethane (4.1), discard two Methyl chloride. The silica gel is spread out in the evaporating dish and has a thickness of less than 10 mm. After the methylene chloride is completely evaporated, the silica gel is dried. Dry in a box at 130 ° C for 16 h, then cool in a desiccator for 30 min, seal into a reagent bottle, and store in a desiccator. 4.21 Diatomaceous earth. 850 ~ 1200 μm (20~15 mesh). It was fired in a muffle furnace at 450 ° C for 4 h, cooled to room temperature, placed in a ground glass bottle, and stored in a desiccator. 4.22 Flori. 75 ~ 180 μm (200 ~ 80 mesh). It was fired in a muffle furnace at 450 ° C for 4 h, cooled to room temperature, placed in a ground glass bottle, and stored in a desiccator. 4.23 2% sodium hydroxide silica gel. 3 Take 98 g of silica gel (4.20) into a glass separatory funnel, add 40 ml of sodium hydroxide solution (4.9) dropwise, and fully oscillate. After shaking, most of the water in the basic silica gel is removed by rotary evaporation under reduced pressure, vacuum drying, or the like, and the silica gel is made into a powder. The prepared silica gel was sealed in a reagent bottle and stored in a desiccator. 4.24 44% sulfuric acid silica gel. Take 56 g of silica gel (4.20) into a glass separatory funnel, add 44 g of sulfuric acid (4.6) dropwise, and shake well to make silica gel. It becomes powdery. The prepared silica gel was sealed in a reagent bottle and stored in a desiccator. 4.25 Copper powder (Cu). 99.5%. Soak the copper powder in the nitric acid solution (4.8) for 10 min before use, remove the surface oxide layer, and wash it with water until neutral. After that, it was washed three times with methanol (4.3) and n-hexane (4.2), and sealed with n-hexane (4.2). 4.26 Quartz wire or quartz wool. The mixture was fired at 450 ° C for 4 h in a muffle furnace, cooled to room temperature, and sealed for storage. 4.27 Quartz sand. The mixture was fired at 450 ° C for 4 h in a muffle furnace, cooled to room temperature, and sealed for storage. 4.28 Dichloromethane-n-hexane mixed solvent. 14. Mix with dichloromethane (4.1) and n-hexane (4.2) in a volume ratio of 1.4. 4.29 Dichloromethane-n-hexane mixed solvent. 1 1. Mix with dichloromethane (4.1) and n-hexane (4.2) in a volume ratio of 1.1. 4.30 Acetone-n-hexane mixed solvent. 1 1. Acetone (4.4) and n-hexane (4.2) were mixed in a volume ratio of 1.1. 4.31 High purity helium. purity ≥ 99.999%. 4.32 Nitrogen. purity ≥ 99.99%.

5 Instruments and equipment

5.1 Gas Chromatography Mass Spectrometer. The inlet has a split/splitless and pulse/high pressure injection function. 5.2 Column. 15 m × 0.25 mm × 0.1  m, fused silica capillary with 5% phenyl-methyl polysiloxane as stationary phase Column, or use another equivalent column. 5.3 Extraction device. pressurized fluid extractor (with multi-standard extraction cell) or Soxhlet extractor (prepared quartz filter cartridge, before use) Burn in a muffle furnace at 450 ° C for 4 h). 5.4 Concentration device. Rotary evaporator, parallel evaporator or nitrogen blow concentrator. 5.5 Glass chromatography column. glass filled column tube with an inner diameter of 8 mm and a length of.200 mm. 5.6 Sampling bottle. wide-mouth brown glass bottle or screw brown glass bottle with Teflon liner cap. 5.7 Collection bottle. eggplant or pear-shaped bottle (polished standard port). 5.8 Dropping funnel. for the matching column, the drip interface is a polished glass port. 5.9 Common instruments and equipment used in general laboratories. 46 samples 6.1 Sample collection and preservation Soil samples were collected and stored in accordance with the relevant requirements of HJ/T 166. The sediment samples of water were in accordance with the relevant requirements of HJ 494. For collection, marine sediment samples were collected in accordance with the relevant requirements of GB 17378.3. Samples are collected and cleaned beforehand. The net sampling bottle (5.6) should be transported back to the laboratory for analysis as soon as possible, and should be sealed and protected from light during transportation. If it cannot be analyzed temporarily, it should Sealed and stored at -10 ° C for 30 d. 6.2 Preparation of samples Remove foreign matter such as stones and leaves from the sample, weigh about 10 g (accurate to 0.01 g) of the sample, add an appropriate amount of water. Sodium sulfate (4.19) or granular diatomaceous earth (4.21) was ground to form a flowing sand. Samples with anhydrous sulfuric acid when using Soxhlet extraction The sodium was dehydrated and the sample was dehydrated with diatomaceous earth using a pressurized fluid extraction. Preparation of air-dried soil and sediment samples can be carried out according to the relevant parts of HJ 166 and GB 17378.3, respectively. Note 1. For high-concentration samples such as soil contaminated sites (such as garbage disposal sites), the sampling volume (1 to 2 g) can be appropriately reduced. Note 2. The sample can also be dehydrated by freeze drying. The lyophilized sample was ground and homogenized into particles of about 1 mm. 6.3 Determination of moisture The dry matter content of the soil samples was determined according to HJ 613, and the moisture content of the sediment samples was determined according to GB. 17378.5 implementation. 6.4 Preparation of samples 6.4.1 Extraction a) pressurized fluid extraction The soil or sediment sample (6.2) is loaded into a suitable extraction cell of the pressurized fluid extractor. Use a micro syringe After 10.0 l carbon-labeled PBDE standard solution (4.12), it was extracted by machine. Air dried sample extraction solvent is dichloromethane - A mixed solvent of n-hexane (4.29), and a fresh solvent for extraction was an acetone-n-hexane mixed solvent (4.30). Heating temperature 100 ° C; The static extraction time was 10 min; the extraction pressure was 1.034×107 Pa (1500 psi); the number of extraction cycles was 3 times. b) Soxhlet extraction Load soil or sediment sample (6.2) into a quartz filter cartridge and add 10.0 l carbon-labeled PBDE standard solution (4.12) After the Soxhlet extraction. The air-dried sample extraction solvent is a dichloromethane-n-hexane mixed solvent (4.29), and the fresh extraction solvent is Acetone-n-hexane mixed solvent (4.30). The extraction time is 18 ~ 24 h, 4 ~ 6 cycles per hour. Note. Soxhlet extraction is required for contaminated sites (eg waste disposal sites). 6.4.2 Concentration and replacement of solvents Transfer the extract to a collection bottle (5.7), concentrate the extract to about 2 ml with a concentration unit (5.4), add 10 Ml n-hexane (4.2) continue to concentrate to about 2 ml, repeat this step 1~2 times until the solvent of the extract is completely converted to positive alkyl. If there is significant moisture in the extract, dehydration is required. Pad a piece of quartz cotton (4.26) in a glass funnel About 5 g of anhydrous sodium sulfate (4.19), the extraction solution was transferred to a glass funnel for dehydration, and after dehydration, 10 ml of n-hexane was used. The funnel was rinsed twice with 5 times, and the extract and eluent were combined into a collection bottle (5.7) and concentrated to about 1 ml with a concentration device (5.4). 6.4.3 Purification If the extract is darker, it must first be purified with sulfuric acid. If the sample contains elemental sulfur, the extract must use copper. Powder sulfur removal. a) sulfuric acid purification Transfer the dehydrated extract to a 100 ml separatory funnel, add 20 ml of n-hexane, and add the appropriate amount (10 ~ 20 Ml) Sulfuric acid (4.6), allowed to stand for 10 min after shaking, the organic phase was retained, and the sulfuric acid layer was discarded. Depending on the color of the sulfate layer Repeat the operation 2~4 times until the color of the sulfuric acid layer is light or colorless. The n-hexane phase was shaken and allowed to stand in 50 ml of water. 10 min, discard the water phase. Repeat the above steps 2~4 times until the water phase is neutral. The hexane phase is filled with quartz wire or quartz wool (4.26) Dehydrated with a conical funnel of anhydrous sodium sulfate (4.19), collected in a collection bottle (5.7), concentrated with a concentration unit (5.4) Up to about 1 ml. Note. During the purification process of sulfuric acid, it is necessary to prevent heat and explosion. After adding sulfuric acid, it should be gently shaken slowly, continuously deflated, and then shaken slightly. b) sulfur removal Add 1 ~ 2 g of copper powder (4.25) to the extract and shake gently, then let stand, use the pipette to extract the extract and transfer to the scale test. In the tube. The collection bottle and copper powder were washed twice with 1-2 ml of n-hexane, and the washing solution was transferred and combined into a graduated test tube. Concentrate The device (5.4) continued to concentrate the extract to approximately 1 ml. c) Composite silica gel column purification Place a small group of quartz wool or quartz wire (4.26) at the bottom of the glass chromatography column (5.5) and add 40 ml of n-hexane (4.2). 1 g of anhydrous sodium sulfate (4.19), 1 g of silica gel (4.20), 2 g of Floridin (4.22), 1 g of silica gel (4.20), 3 g 2% sodium sulphate silica gel (4.23), 1 g silica gel (4.20), 8 g 44% sulfuric acid silica gel (4.24), 1 g silica gel (4.20), 1 g anhydrous sodium sulfate (4.19), the composite silica gel column packing diagram is shown in Figure 1. The n-hexane solution is discharged to make the n-hexane liquid surface just Well, it is flush with the anhydrous sodium sulfate on the silica gel column. Transfer the extract to a composite silica gel column and connect to the dropping funnel (5.8) Then, rinse with 120 ml of dichloromethane-n-hexane mixed solvent (4.28) to adjust the elution speed to about 2.5 ml/min. Approximately 1 drop/s), collect the eluent using a collection bottle (5.7). Note. If verified, a commercially available finished composite silica gel column can also be used for sample purification. Figure 1 Schematic diagram of the loading of composite silica gel column 66.4.4 Concentrated and concentrated Concentrate the eluent to about 2 ml with a concentration unit (5.4), add 10 ml of n-hexane (4.2) and continue to concentrate until about Repeat this step twice with 2 ml. Transfer the concentrate to a graduated tube, continue to concentrate to less than 1 ml, add 20.0 l Carbon-labeled PCB-209 solution (4.14), shake well, transfer to a sample bottle and dilute to 1.0 ml, to be tested. Note. If the extract cannot be analyzed in time, it should be stored at 4 °C in the dark and completed within 30 days. 6.5 Preparation of blank samples A quartz sample (4.27) was used instead of the sample, and a blank sample was prepared in the same manner as in sample preparation (6.4).

7 Analysis steps

7.1 Measurement conditions 7.1.1 Gas Chromatography Reference Conditions Inlet temperature. 270 ° C, pulse or high pressure (120 kPa, 1 min) without split injection; carrier gas flow rate. 2.0 ml/min; Injection volume. 1.0 l; oven temperature. 60 ° C (for 1 min), rise to.200 ° C at 30 ° C/min (for 1 min), It was raised to 260 ° C at 10 ° C/min and then raised to 320 ° C at 30 ° C/min (for 3 min). 7.1.2 Mass Spectrometry Reference Conditions Ion source temperature. 230 ° C; transmission line temperature. 300 ° C; ionization energy. 70 eV. Data collection method. choose Ion detection. The mass-to-charge ratio of the quantitative and qualitative ions of PBDEs is determined based on the mass spectra obtained from the full-scan standard. See Appendix B. 7.2 Instrument performance check Mass spectrometry should be performed automatically before the instrument is used. Inject 1.0 μl of trifluorotriphenyl before and 24 h after sample analysis The instrument system is inspected using the phosphine standard solution (4.18). The critical ion abundance of DFTPP should meet the requirements of Table 1. Table 1 DFTPP key ion and ion abundance standards Mass ion/m/z abundance standard mass ion/m/z abundance standard 51% to 80% of the base peak 5% to 9% of the.199 198 peak 68 less than 69 peaks 2% 275 base peaks 10% to 60% 70 less than 69 peaks 2% 365 greater than 198 peaks 1% 127 base peak 10%~80% 441 exists and less than 442 peak 24% 197 2% 442 base peak less than 198 peak, or 50% larger than 198 peak 198 base peak, or 50% greater than 442 peaks 15%~24% of 443 442 peaks 7.3 Calibration 7.3.1 Preparation of the standard series Take 6 1.5 ml brown injection vials, use n-hexane (4.2), polybrominated diphenyl ether solution (4.11), extract The internal standard solution (4.12) and the injection internal standard use solution (4.14) were prepared according to Table 2 into six standard series of different concentrations. 7 Table 2 Preparation of PBDE standard series solution Standard Series CS-1 CS-2 CS-3 CS-4 CS-5 CS-6 Polybromodiphenyl ether standard series solution concentration/ng/ml 2.00 5.00 20.0 50.0 100.200 BDE-209 concentration/ng/ml 20.0 50.0.200 500 1000.2000 N-hexane volume/μl 969 967 960 945 920 870 Polybromodiphenyl ether solution volume/μl 1.0 2.5 10.0 25.0 50.0 100 Extract internal standard solution volume/μl 10.0 10.0 10.0 10.0 10.0 10.0 Injection internal standard using liquid volume/μl 20.0 20.0 20.0 20.0 20.0 20.0 7.3.2 Establishment of calibration curve According to the instrument reference analysis conditions (7.1), GC-MS determination was carried out in order from low concentration to high concentration. Target combination The concentration of the substance is the abscissa, the ratio of the target compound to the internal standard/extraction internal standard quantitative ion response value and the internal standard/extraction internal standard concentration The product of the product is plotted on the ordinate. 7.4 Sample determination The measurement of the sample (6.4) was carried out in accordance with the same instrument conditions as the calibration curve establishment (7.3.2). 7.5 Blank test The blank sample (6.5) was measured in the same manner as in the sample measurement (7.4).

8 Calculation and representation of results

8.1 Qualitative analysis It is characterized by the retention time, fragment ion mass-to-charge ratio and abundance ratio of PBDE and its carbon-labeled congeners. In the sample The relative abundance ratio of the qualitative and quantitative ions of the target is compared with the relative abundance of the recently obtained standard sample, and the relative deviation should be Less than 20%. The total ion chromatogram of PBDE is shown in Figure 2, where the chromatogram of PBDE and its carbon-labeled congeners The peak is a co-eluting peak. 1-BDE-28/13C-BDE-28; 2-BDE-47/13C-BDE-47; 3-BDE-100/13C-BDE-100; 4-BDE-99/13C-BDE-99; 5-13C-PCB-209; 6-BDE-154/13C-BDE-154; 7-BDE-153/13C-BDE-153; 8-BDE-183/13C-BDE-183; 9-BDE-209/13C-BDE-209. Figure 2 Total ion chromatogram of PBDE 88.2 Calculation of results 8.2.1 Calculation of relative response factors The internal standard relative response factor is calculated according to formula (1). (1) Where. RRFcs-relative response factors for extracting internal standards; As-calibration standard compound peak area in the standard solution; Extracting the internal standard peak area in the Acs-calibration standard solution; Extraction of internal standard mass in Qcs-calibration standard solution, ng; Qs - the mass of the target compound in the calibration standard solution, ng. Calculate the relative response factor of the injection internal standard according to formula (2). (2) Where. RRFrs-relative response factor of the injection internal standard; Extracting the internal standard peak area in the Acs-calibration standard solution; The internal standard peak area of the injection in the Ars-calibration standard solution; Qrs-calibration standard solution injection internal standard mass, ng; The internal standard mass, ng, was extracted from the Qcs-calibration standard solution. 8.2.2 Calculation of extraction internal standard recovery rate The internal standard recovery rate is calculated according to formula (3). Csirs Rs Rs Csi QRRF %  (3) Where. the recovery of the internal standard i extracted from the Rc-sample; Extracting the peak area of the internal standard i in the Acsi-sample; The peak area of the internal standard of the injection in the Ars-sample; Qrs-the quality of the internal standard of the sample in the sample, ng; RRFrs-the average relative response factor of the injection internal standard; The mass of the internal standard i, ng, was extracted from the Qcsi-sample. 8.2.3 Calculation of target compounds The recovery rate of the extracted internal standard is 30%~135% (13C-BDE-209 is 20%~200%), and the sample is inspected. The mass of the PBDE congener is cal...

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