Valid

GB 23200.55-2016Food safety national standard -- Determination of 21 fumigants in foodstuffs -- Headspace gas chromatography (English PDF)

食品中21种熏蒸剂残留量的测定顶空气相色谱法

Preview PDF

This is a limited preview

Buy now to download the full PDF (9 pages)

Need quotation for your management?

Get a formal quotation for GB 23200.55-2016 in 30 minutes.

Issued by

National Health and Family Planning Commission of the People 's Republic of China

Level / Type

National · Mandatory

Issue date

December 18, 2016

Implementation date

June 18, 2017

Scope

GB 23200.55-2016 is the English-translated version of 食品中21种熏蒸剂残留量的测定顶空气相色谱法.

GB 23200.55-2016 — This standard specifies the presence of 1,1,1-trichloroethane, trans-1,3-dichloropropene, cis-1,3-dichloropropene, trichlorethylene, 1,2-bis Chloropropane, bromodichloromethane, 1,1,2-trichloroethane, tetrachlorethylene, tricetral chloride, bromoform, 1,1,2,2-tetrachloroethane, 1,3-Dichlorobenzene, 1,4-dichlorobenzene, 1,2-dichlorobenzene, 1,2,4-trichlorobenzene, 1,2,3-trichlorobenzene, hexachlorobutadiene, Dibromoethane, 1,2-dichloroethane, carbon tetrachloride, trichloromethane 21 kinds of fumigant residues in the headspace gas chromatography detection method.

This standard applies to corn, brown rice, peanuts, soybeans, beans and other foods in the determination of 21 kinds of fumigant residues, other food can refer to carried out.

Found what you need?

Document preview — GB 23200.55-2016

National Standard of the People's Republic of China

Classification: G 25
Replacing: SN/T 2238-2008

Issued by: National Health and Family Planning Commission of the People 's Republic of China

Foreword
1 Scope
2 Normative reference documents
3 Principle
4 Reagents and materials
4.1 Reagents
4.2 Standards
4.3 Standard solution preparation
5 Instruments and equipment
6 Preparation and storage of samples
6.1 Preparation of the sample
6.2 Sample storage
7 Analysis steps
7.1 Extraction
7.2 Determination
7.3 Blank experiment
8 Results are calculated and expressed
9 Precision
10.1 Quantitation limits
10.2 Recovery rate
21 Kinds of fumigant standard information

Foreword

This standard replaces SN/T 2238-2008 "21 kinds of fumigants in the import and export of food detection method headspace gas chromatography." Compared with SN/T 2238-2008, the main changes are as follows.

- Standard text format is modified to national standard text format for food safety;

- the name of the "import and export food" to "food";

- increase the "other food reference implementation" in the standard range.

This standard replaced the previous version of the standard release.

-SN/T 2238-2008.

National standards for food safety Determination of 21 fumigants in foodstuffs - Headspace gas chromatography

1 Scope

This standard specifies the presence of 1,1,1-trichloroethane, trans-1,3-dichloropropene, cis-1,3-dichloropropene, trichlorethylene, 1,2-bis Chloropropane, bromodichloromethane, 1,1,2-trichloroethane, tetrachlorethylene, tricetral chloride, bromoform, 1,1,2,2-tetrachloroethane, 1,3-Dichlorobenzene, 1,4-dichlorobenzene, 1,2-dichlorobenzene, 1,2,4-trichlorobenzene, 1,2,3-trichlorobenzene, hexachlorobutadiene, Dibromoethane, 1,2-dichloroethane, carbon tetrachloride, trichloromethane 21 kinds of fumigant residues in the headspace gas chromatography detection method.

This standard applies to corn, brown rice, peanuts, soybeans, beans and other foods in the determination of 21 kinds of fumigant residues, other food can refer to carried out.

2 Normative reference documents

The following documents are indispensable for the application of this document. For dated references, only the dated edition applies to this file. For undated references, the latest edition (including all modifications) applies to this document.

GB 2763 National Standard for Food Safety - Maximum Residue Limit of Pesticides in Foodstuffs GB/T 6682 Analytical laboratory water specifications and test methods

3 Principle

In the sealed container, volatile fumigant molecules in a certain temperature in the gas-solid two-phase to achieve a dynamic balance. At this time the fumigant is in the air the concentration of the phase is proportional to its concentration in the solid phase, and the concentration of the fumigant can be calculated by measuring the concentration of the fumigant in the gas phase Quantitative and external standard method.

4 Reagents and materials

Unless otherwise specified, all reagents are of analytical grade and water is in accordance with the primary water specified in GB/T 6682.

4.1 Reagents

4.1.1 n-hexane (C6H14). pesticide residues.

4.1.2 anhydrous sodium sulfate (Na2SO4). 650 °C burning 4 h, set the dryer in the spare.

4.2 Standards

4.2.1 Fumigant Standard. Purity greater than or equal to 99%. (See Table A1 in Appendix A).

4.3 Standard solution preparation

4.3.1 Trichloromethane, carbon tetrachloride and other 21 kinds of fumigants Standard stock solution. accurate removal of chloroform, carbon tetrachloride, 1,2-dibromoethane and other 21 fumigants in the appropriate volume, and its density (see Appendix A, Table A1) for weight calculation, with n-hexane Respectively, with a concentration of 1000 µg/mL of the standard stock solution. The solution is stored in a refrigerator at 0 to 4 ° C.

4.3.2 Trichloromethane, carbon tetrachloride and other 21 kinds of fumigants Standard mixed working solution. according to the need to use n-hexane diluted with the appropriate concentration of the standard Quasi-mixed working solution, the solution in 0 °C ~ 4 °C refrigerator.

5 Instruments and equipment

5.1 Gas Chromatograph. equipped with electronic capture detector.

5.2 Analysis of balance. 0.01 g and 0.0001 g.

5.3 Headspace syringe. 1.0 mL.

5.4 Headspace unit.

5.5 Headspace Bottle. 20.0 mL.

5.6 sealed plastic centrifuge tube. 50 mL.

5.7 Ultrasonic instrument.

6 Preparation and storage of samples

6.1 Preparation of the sample

Replace the sample of about 500 g, the sampling site according to GB 2763 Appendix A implementation, into the clean container, sealed, marked mark.

6.2 Sample storage

The sample was stored at -18 ° C or lower. During sample and sample preparation, the sample should be protected from contamination or residue the change.

7 Analysis steps

7.1 Extraction

Weigh the sample 5 g (accurate to 0.01 g) in 50 mL stoppered plastic centrifuge tube, accurately add 15.0 mL n-hexane dissolved and ultrasonic extraction 5 min, centrifuge. Accurately remove 10.0 mL of sample in a headspace bottle and immediately seal with a rubber stopper with a Teflon film lining Empty device, at 60 °C constant temperature 0.5 h, the extraction of.200 µL upper gas for gas chromatography analysis.

7.2 Determination

7.2.1 Gas Chromatographic Reference Conditions

A) Column. HP-624 quartz capillary column, 30 m x 0.53 mm (id) x 2.05 m, or equivalent;

B) Column temperature. 40 ° C (for 1 min) min/5 C 140 °C (for 30 min);

C) Inlet temperature..200 ° C.

D) Detector temperature. 250 ° C.

E) Carrier gas. helium, purity greater than or equal 99.999%, flow rate 1.2 mL/min;

F) Injection volume..200 µL.

7.2.2 Determination of gas chromatography

According to the content of fumigant in the sample solution, the standard working solution with similar concentration, the standard working solution and the fumigant in the sample solution the response value should be within the linear range of the instrument detection. Standard working solution and sample volume.

The standard solution and sample solution were determined according to the conditions specified in 7.1. The gas chromatogram of the fumigant reference material and sample is shown in Appendix B.

B.1-B.6.

7.3 Blank experiment

Do not take the sample according to the above steps.

8 Results are calculated and expressed

Use the chromatographic data processor or (1) to calculate the residual amount of fumigant in the sample. The calculated result should be deducted from the blank value.

H · c · V

Hs · m

Where. X - the amount of a fumigant in the sample, in milligrams per kilogram, mg/kg;

H - the peak of a fumigant in the sample solution;

H s - standard working fluid in a fumigant peak high;

C - the concentration of a fumigant in standard working fluid, in micrograms per milliliter, g/mL;

V - the volume of the solvent extracted, in milliliters, mL;

M - the amount of sample to be weighed, in g, g.

Note. The result of the calculation shall be deducted from the blank value. The result of the measurement shall be expressed as the arithmetic mean of the parallel measurement, and two valid digits shall be retained.

9 Precision

9.1 The ratio of the absolute difference between the two independent determinations obtained under reproducible conditions and their arithmetic mean (percentage) shall be in accordance with the Record the requirements of D.

9.2 The ratio of the absolute difference between the two independent determinations obtained under reproducibility and its arithmetic mean (percentage) shall be in accordance with the Record the requirements of E.

10% limit and recovery rate

10.1 Quantitation limits

The limit of the 21 fumigants involved in this method was 0.01 mg/kg.

10.2 Recovery rate

When adding levels of 0.01-0.10 mg/kg, see Appendix C for the recovery of 21 fumigants in different matrices.

Appendix A

(Informative)

21 Kinds of fumigant standard information

Table A.1 Information on 21 fumigant standards

No. Sample name Molecular weight Molecular formula CAS No. Density 1 1,1,1-trichloroethane 133.35 CH3CCl3 71-55-6 1.350 2 trans-1,3-dichloropropene 110.97 C3H4Cl2 10061-02-6 1.160 3-cis-1,3-dichloropropene 110.97 C3H4Cl2 10061-02-5 1.160 4 trichlorethylene 131.39 ClCH = CCl2 79-01-6 1.465 5 1,2-dichloropropane 112.9 CH3CHClCH2Cl 78-87-5 1.260

6 Bromodichloromethane 163.8 CHBrCl2 75-27-4 2.006 7 1,1,2-trichloroethane 133.4 CHCl2CH2Cl 79-00-5 4.550 8 tetrachlorethylene 165.82 CCl2CCl2 127-18-4 1.631

9 Dibromochloromethane 208.3 CHBr2Cl 124-48-1 1.440 10 bromoform 252.73 CHBr3 75-25-2 2.889 11 1,1,2,2-tetrachloroethane 167.86 CHCl2CHCl2 79-34-5 1.600 12 1,3-dichlorobenzene 147.00 C6H4Cl2 541-73-1 1.290 13 1,4-dichlorobenzene 147.00 C6H4Cl2 106-46-7 1.458 14 1,2-dichlorobenzene 147.00 C6H4Cl2 95-50-1 1.460 15 1,2,4-Trichlorobenzene 181.45 C6H3Cl3 120-82-1 1.450 16 1,2,3-trichlorobenzene 181.45 C6H3Cl3 87-61-6 1.450 17 hexachlorobutadiene 260.76 C4Cl6 87-68-3 1.682 18 1,2-dibromoethane 187.88 C2H4Br2 106-93-4 2.177 19 1,2-dichloroethane 98.97 C2H4Cl2 107-06-2 1.260 Carbon tetrachloride 153.84 CCl4 56-23-5 1.592

21 Trichloromethane 119.38 CHCl3 67-66-3 1.448 Appendix B (Informative) 21 fumigant standards and sample gas chromatograms Min0 5 10 15 20 25 30 35 Hz 1. Trichloromethane 2.1.1.1-Trichloroethane 3. Carbon tetrachloride 4.1.2-Dichloroethane 5. Trichlorethylene 6.1.2-Dichloropropane 7. Bromine Dichloromethane 8. cis-1.3-dichloropropene 9. trans-1,3-dichloropropene 10.1.1.2-trichloroethane 11. tetrachlorethylene 12. dibromo Chloromethane 13.1.2-Dibromoethane 14. Bromine 15.1.1.2.2.-Tetrachloroethane 16.1.3-Dichlorobenzene 17.1.4-Dichlorobenzene 18.1.2-Dichlorobenzene 19.1.2.4-Trichlorobenzene 20. Hexachlorobutadiene 21.1.2.3-Trichlorobenzene

Figure B.1 Standard fumigants for 21 fumigants

Min0 5 10 15 20 25 30 35 Hz ECD1 A, (SIG20363.D) 9.

Figure B.2 Gas chromatogram of soybean empty sample

Figure B.3 Gas chromatogram of small bean empty sample

Figure B.4 Gas chromatogram of peanut blank sample

Min0 5 10 15 20 25 30 35 Hz ECD1 A, (SIG20364.D) 9.

Min0 5 10 15 20 25 30 35 Hz ECD1 A, (SIG20366.D) 9.

Min0 5 10 15 20 25 30 35 Hz ECD1 A, (SIG20365.D) 9.

Figure B.5 Gas Chromatogram of Brown Rice Blank Sample

Min0 5 10 15 20 25 30 35 Hz ECD1 A, (SIG20369.D) .9 .4

Figure B.6 Gas chromatogram of corn blank

Min 5 10 15 20 25 30 35 Hz ECD1 A, (SIG20351.D) .2 .5 .8 .1 0.

Figure B.7 Gas chromatograms for the addition of low-limit samples

Appendix C

(Informative)

The recovery of 21 fumigants in different substrates

Table C.1 Recovery of 21 fumigants in different substrates

No. Sample name

Recovery rate(%)

Corn brown rice peanut bean 1 1,1,1-trichloroethane 78.0 to 95.2 81.0 to 97.5 76.5 to 96.1 79.0 to 98.0 73.0 to 98.0 2 trans-1,3-dichloropropene 74.0 to 98.5 74.0 to 98.5 75.0 to 98.5 76.8 to 98.0 72.3 to 98.5 3-cis-1,3-dichloropropene 72.0 to 94.6 77.0 to 98.0 73.5 to 95.5 72.0 to 98.0 72.0 to 98.0

4 Trichlorethylene 70.0 to 94.4 74.0 to 96.7 72.0 to 95.3 71.0 to 95.5 72.0 to 94.4 5 1,2-dichloropropane 73.0 to 94.7 77.0 to 98.0 75.0 to 95.6 73.0 to 95.0 73.0 to 94.7

6 Bromodichloromethane 74.0 to 98.5 74.0 to 96.5 76.0 to 98.5 73.4 to 99.5 70.2 to 98.5 7 1,1,2-trichloroethane 73.0 to 98.5 74.0 to 96.5 75.0 to 98.5 73.4 to 98.0 70.2 to 98.0 8 tetrachlorethylene 77.3 ~ 97.5 78.0 ~ 98.0 72.3 ~ 98.0 73.5 ~ 99.5 72.8 ~ 98.5

9 Dibromochloromethane 71.4 ~ 97.0 74.4 ~ 97.0 80.0 ~ 96.1 78.0 ~ 99.5 70.1 ~ 98.0

10 Bromine 78.0 ~ 96.5 81.0 ~ 98.0 80.0 ~ 96.1 79.0 ~ 97.5 77.8 ~ 98.0 11 1,1,2,2-tetrachloroethane 70.0 to 97.0 75.5 to 98.0 72.0 to 95.1 72.0 to 97.5 72.8 to 98.0 12 1,3-dichlorobenzene 73.0 to 99.0 72.0 to 98.0 71.0 to 95.0 72.8 to 98.0 73.0 to 98.0 13 1,4-Dichlorobenzene 75.2 to 98.5 72.0 to 96.0 75.7 to 97.0 73.0 to 98.0 71.7 to 97.5 14 1,2-dichlorobenzene 71.0 to 98.0 74.0 to 96.8 78.2 to 98.5 71.0 to 98.5 70.1 to 97.5 15 1,2,4-Trichlorobenzene 74.0 to 98.5 73.5 to 97.0 79.0 to 98.0 76.8 to 98.0 71.7 to 97.5 16 1,2,3-Trichlorobenzene 74.0 ~ 98.0 72.0 ~ 98.5 72.3 ~ 98.0 73.4 ~ 99.5 72.8 ~ 98.5

17 Hexachlorobutadiene 72.2 to 98.0 71.0 to 98.5 78.0 to 99.0 79.0 to 98.0 75.0 to 98.0 18 1,2-Dibromoethane 72.3 to 98.5 72.0 to 98.5 72.3 to 99.0 73.4 to 98.0 73.0 to 97.5 19 1.2-Dichloroethane 72.1 to 98.0 72.0 to 98.5 72.3 to 98.0 73.5 to 98.0 70.2 to 98.0

20 Carbon tetrachloride 74.0 ~ 98.5 74.0 ~ 98.5 72.4 ~ 98.0 73.4 ~ 99.5 70.2 ~ 97.5

21 Trichloromethane 73.0 to 98.5 74.0 to 98.0 75.0 to 91.0 73.3 to 99.5 70.3 to 98.5 Appendix D (Normative appendix) Laboratory repeatability requirements

Table D.1 Laboratory repeatability requirements

Measured component content Mg/kg Precision <=0.001 36 > 0.01 > 1 14 Appendix E (Normative appendix) Inter-laboratory reproducibility requirements

Table E.1 Inter-laboratory reproducibility requirements

Measured component content Mg/kg Precision <=0.001 54 > 0.01 > 1 19

......
This preview omits tables, figures, formulas and parts of the technical clauses. The complete document — 9 pages — is available in the English PDF.

How to Download GB 23200.55-2016

1
Add to cart
Click "Download PDF" on this page and choose "Buy this standard". You can add more standards before checkout.
2
Checkout
Enter your email and billing details. Payment is processed securely by Stripe (cards or bank transfer). Prefer bank details? Request a quotation (min. order $300).
3
Instant delivery (0–9 sec)
Delivery is automatic: within seconds of payment you'll receive an email with a secure download link. The link stays valid for 72 hours.
4
Invoice included
A tax invoice is attached to the confirmation email. Need a custom invoice? Contact us.