GB 31604.31-2025 National food safety standard - Food contact materials and products - Determination of residual and migration of vinyl chloride, 1,1- dichloroethylene and 1,1- dichloroethane (English Version)
National food safety standard - Food contact materials and products - Determination of residual and migration of vinyl chloride, 1,1- dichloroethylene and 1,1- dichloroethane
GB 31604.31-2025 National food safety standard - Food contact materials and products - Determination of residual and migration of vinyl chloride, 1,1- dichloroethylene and 1,1- dichloroethane English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
National Standard of the People's Republic of China
GB 31604.21-2025
National Food Safety Standard
Determination of Residue and Migration Levels of Vinyl Chloride, 1,1-Dichloroethylene, and 1,1-Dichloroethane in Food Contact Materials and Articles
Issue date: 2025-09-02 Implementation date: 2026-03-02
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the National Health Commission of the People’s Republic of China
Contents
Foreword
1 Scope
2 Principle
3 Reagents and Materials
4 Instruments and Equipment
5 Analytical Procedure
6 Expression of Analytical Results
7 Precision
8 Others
National Food Safety Standard
Determination of Residue and Migration Levels of Vinyl Chloride, 1,1-Dichloroethylene, and 1,1-Dichloroethane in Food Contact Materials and Articles
1 Scope
This standard specifies methods for determining the residual levels and migration of vinyl chloride, 1,1-dichloroethylene, and 1,1-dichloroethane in food contact materials and articles.
This standard applies to the determination of residues and migration levels of vinyl chloride, 1,1-dichloroethylene, and 1,1-dichloroethane in plastic, coating, adhesive, paper and paper product, and ink-based food contact materials and articles.
Part I Determination of Residual Levels of Vinyl Chloride, 1,1-Dichloroethylene, and 1,1-Dichloroethane
Method 1 Gas Chromatography
2. Principle
The sample is placed in a headspace vial, dissolved or thoroughly dispersed in N,N-dimethylacetamide, and heated to achieve gas-liquid equilibrium for the target components vinyl chloride, 1,1-dichloroethylene, and 1,1-dichloroethane. A quantitative volume of the headspace gas is injected into a gas chromatograph for separation. Detection is performed using an electron capture detector (ECD). Qualitative analysis is based on retention time, and quantitative analysis employs the external standard method using peak area.
3 Reagents and Materials
Unless otherwise specified, reagents used in this method are analytical grade. Water complies with Grade 1 water as defined by GB/T 6682.
3.1 Reagents
N,N-Dimethylacetamide: Purity > 99%.
3.2 Standards
3.2.1 Vinyl Chloride (C₂H₃Cl, CAS No.: 75-01-4): Standard solution certified by the national authority and issued with a Certificate of Analysis, concentration 1000 mg/L, in methanol solvent.
3.2.2 1,1-Dichloroethylene (C₂H₂Cl₂, CAS No.: 75-35-4): Purity ≥99.5%, or a standard material certified by the state and granted a Certificate of Analysis.
3.2.3 1,1-Dichloroethane (C₂H₄Cl₂, CAS No.: 75-34-3): Purity ≥99.5%, or a national certified reference material with a certificate of analysis.
Note: All three substances above are highly volatile. Standard samples should be stored sealed in a refrigerator away from light. Once opened, ampoule-sealed standard samples must be used immediately and cannot be resealed for future use as standard material. Exercise personal protection when handling standard samples to avoid inhalation or skin contact.
3.3 Preparation of Standard Solutions
3.3.1 1,1-Dichloroethylene Standard Stock Solution (1000 mg/L): Accurately weigh 10 mg (to the nearest 0.1 mg) of 1,1-dichloroethylene standard material. Dissolve in N,N-dimethylacetamide and transfer to a 10 mL brown volumetric flask. Dilute to the mark and mix thoroughly. Transfer to a brown storage bottle. Store tightly sealed in a 4°C refrigerator protected from light. Shelf life: 3 months.
3.3.2 1,1-Dichloroethane Standard Stock Solution (1000 mg/L): Accurately weigh 10 mg (to the nearest 0.1 mg) of 1, Transfer to a 10 mL brown volumetric flask, dilute to the mark, and mix thoroughly. Transfer to a brown storage bottle, store tightly closed in a 4°C refrigerator protected from light, with a shelf life of 3 months.
3.3.3 Mixed Standard Intermediate Solution (10 mg/L): Accurately pipette 1.2 mL of vinyl chloride standard solution (3.2.1), 1,1-dichloroethylene standard stock solution (3.3.1), and 1,1-dichloroethane standard stock solution (3.3.2) into the same 10 mL brown volumetric flask. Add N, N,N-dimethylacetamide to the mark and mix thoroughly to obtain a mixed standard intermediate solution of vinyl chloride, 1,1-dichloroethylene, and 1,1-dichloroethane, each with a mass concentration of 10 mg/L. Transfer to brown storage bottles, store sealed in a 4°C refrigerator protected from light, with a shelf life of 1 month.
3.3.4 Standard Working Solution Series: Add 10.0 mL of N,N-dimethylacetamide to each of 5 headspace vials. Using a micropipette, slowly inject 50.0 μL, 75.0 μL, 100 μL, 150 μL, and 200 μL of the mixed standard intermediate solution into each vial. Immediately cap and seal. Mix thoroughly to obtain the mixed standard working solution of vinyl chloride, 1,1-dichloroethylene, and 1,1-dichloroethane in N,N-dimethylacetamide. with target concentrations of 0.050 mg/L, 0.075 mg/L, 0.10 mg/L, 0.15 mg/L, and 0.20 mg/L, respectively. Prepare and use immediately.
4 Instruments and Equipment
4.1 Gas chromatograph: Equipped with an electron capture detector (ECD).
4.2 Headspace autosampler.
4.3 Headspace vials: 20 mL capacity, with caps fitted with silicone or butyl rubber seals.
4.4 Micropipette: 200 μL capacity.
4.5 Electronic balance: Readings of 0.0001 g and 0.1 g.
5 Analytical Procedure
5.1 Preparation of Test and Blank Sample Solutions
5.1.1 Sample Solution Preparation
For plastic samples, paper, and paper products, cut or crush the sample to a maximum diameter of ≤0.5 cm. For coated, adhesive, or ink-based food contact materials and articles, scrape the dried coating, adhesive, or ink layer and grind it to a maximum diameter of ≤0.5 cm.
Weigh 1 g (accurate to 0.1 g) of the crushed sample into a headspace vial. Add 10.0 mL of N,N-dimethylacetamide, immediately cap and seal the vial, shake to dissolve or thoroughly disperse the sample, and place it in the headspace autosampler for analysis.
5.1.2 Preparation of Blank Sample Solution
Follow steps 5.1.1 except omit sample addition. Prepare the blank sample solution and place it in the headspace autosampler for analysis. Note: Due to the strong volatility of the target compound, avoid prolonged grinding in room-temperature equipment without refrigeration, which may cause sample heating and result in volatilization loss of the target compound.
5.2 Instrument Reference Conditions
5.2.1 Headspace reference conditions are as follows:
a) Dosing loop: 1 mL or 3 mL;
b) Equilibration temperature: 80 °C;
c) Dosing loop temperature: 90 °C;
d) Transfer line temperature: 100 °C;
e) Equilibration time: 30 min;
f) Pressurization time: 0.20 min;
g) Injection port filling time: 0.10 min;
h) Injection port equilibration time: 0.10 min;
i) Injection time: 1.50 min.
GB 31604.31-2025 National food safety standard - Food contact materials and products - Determination of residual and migration of vinyl chloride, 1,1- dichloroethylene and 1,1- dichloroethane (English Version)
Standard No.
GB 31604.31-2025
Status
valid
Language
English
File Format
PDF
Word Count
9500 words
Price(USD)
285.0
Implemented on
2025-9-16
Delivery
via email in 1~3 business day
Detail of GB 31604.31-2025
Standard No.
GB 31604.31-2025
English Name
National food safety standard - Food contact materials and products - Determination of residual and migration of vinyl chloride, 1,1- dichloroethylene and 1,1- dichloroethane
GB 31604.31-2025 National food safety standard - Food contact materials and products - Determination of residual and migration of vinyl chloride, 1,1- dichloroethylene and 1,1- dichloroethane English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
National Standard of the People's Republic of China
GB 31604.21-2025
National Food Safety Standard
Determination of Residue and Migration Levels of Vinyl Chloride, 1,1-Dichloroethylene, and 1,1-Dichloroethane in Food Contact Materials and Articles
Issue date: 2025-09-02 Implementation date: 2026-03-02
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the National Health Commission of the People’s Republic of China
Contents
Foreword
1 Scope
2 Principle
3 Reagents and Materials
4 Instruments and Equipment
5 Analytical Procedure
6 Expression of Analytical Results
7 Precision
8 Others
National Food Safety Standard
Determination of Residue and Migration Levels of Vinyl Chloride, 1,1-Dichloroethylene, and 1,1-Dichloroethane in Food Contact Materials and Articles
1 Scope
This standard specifies methods for determining the residual levels and migration of vinyl chloride, 1,1-dichloroethylene, and 1,1-dichloroethane in food contact materials and articles.
This standard applies to the determination of residues and migration levels of vinyl chloride, 1,1-dichloroethylene, and 1,1-dichloroethane in plastic, coating, adhesive, paper and paper product, and ink-based food contact materials and articles.
Part I Determination of Residual Levels of Vinyl Chloride, 1,1-Dichloroethylene, and 1,1-Dichloroethane
Method 1 Gas Chromatography
2. Principle
The sample is placed in a headspace vial, dissolved or thoroughly dispersed in N,N-dimethylacetamide, and heated to achieve gas-liquid equilibrium for the target components vinyl chloride, 1,1-dichloroethylene, and 1,1-dichloroethane. A quantitative volume of the headspace gas is injected into a gas chromatograph for separation. Detection is performed using an electron capture detector (ECD). Qualitative analysis is based on retention time, and quantitative analysis employs the external standard method using peak area.
3 Reagents and Materials
Unless otherwise specified, reagents used in this method are analytical grade. Water complies with Grade 1 water as defined by GB/T 6682.
3.1 Reagents
N,N-Dimethylacetamide: Purity > 99%.
3.2 Standards
3.2.1 Vinyl Chloride (C₂H₃Cl, CAS No.: 75-01-4): Standard solution certified by the national authority and issued with a Certificate of Analysis, concentration 1000 mg/L, in methanol solvent.
3.2.2 1,1-Dichloroethylene (C₂H₂Cl₂, CAS No.: 75-35-4): Purity ≥99.5%, or a standard material certified by the state and granted a Certificate of Analysis.
3.2.3 1,1-Dichloroethane (C₂H₄Cl₂, CAS No.: 75-34-3): Purity ≥99.5%, or a national certified reference material with a certificate of analysis.
Note: All three substances above are highly volatile. Standard samples should be stored sealed in a refrigerator away from light. Once opened, ampoule-sealed standard samples must be used immediately and cannot be resealed for future use as standard material. Exercise personal protection when handling standard samples to avoid inhalation or skin contact.
3.3 Preparation of Standard Solutions
3.3.1 1,1-Dichloroethylene Standard Stock Solution (1000 mg/L): Accurately weigh 10 mg (to the nearest 0.1 mg) of 1,1-dichloroethylene standard material. Dissolve in N,N-dimethylacetamide and transfer to a 10 mL brown volumetric flask. Dilute to the mark and mix thoroughly. Transfer to a brown storage bottle. Store tightly sealed in a 4°C refrigerator protected from light. Shelf life: 3 months.
3.3.2 1,1-Dichloroethane Standard Stock Solution (1000 mg/L): Accurately weigh 10 mg (to the nearest 0.1 mg) of 1, Transfer to a 10 mL brown volumetric flask, dilute to the mark, and mix thoroughly. Transfer to a brown storage bottle, store tightly closed in a 4°C refrigerator protected from light, with a shelf life of 3 months.
3.3.3 Mixed Standard Intermediate Solution (10 mg/L): Accurately pipette 1.2 mL of vinyl chloride standard solution (3.2.1), 1,1-dichloroethylene standard stock solution (3.3.1), and 1,1-dichloroethane standard stock solution (3.3.2) into the same 10 mL brown volumetric flask. Add N, N,N-dimethylacetamide to the mark and mix thoroughly to obtain a mixed standard intermediate solution of vinyl chloride, 1,1-dichloroethylene, and 1,1-dichloroethane, each with a mass concentration of 10 mg/L. Transfer to brown storage bottles, store sealed in a 4°C refrigerator protected from light, with a shelf life of 1 month.
3.3.4 Standard Working Solution Series: Add 10.0 mL of N,N-dimethylacetamide to each of 5 headspace vials. Using a micropipette, slowly inject 50.0 μL, 75.0 μL, 100 μL, 150 μL, and 200 μL of the mixed standard intermediate solution into each vial. Immediately cap and seal. Mix thoroughly to obtain the mixed standard working solution of vinyl chloride, 1,1-dichloroethylene, and 1,1-dichloroethane in N,N-dimethylacetamide. with target concentrations of 0.050 mg/L, 0.075 mg/L, 0.10 mg/L, 0.15 mg/L, and 0.20 mg/L, respectively. Prepare and use immediately.
4 Instruments and Equipment
4.1 Gas chromatograph: Equipped with an electron capture detector (ECD).
4.2 Headspace autosampler.
4.3 Headspace vials: 20 mL capacity, with caps fitted with silicone or butyl rubber seals.
4.4 Micropipette: 200 μL capacity.
4.5 Electronic balance: Readings of 0.0001 g and 0.1 g.
5 Analytical Procedure
5.1 Preparation of Test and Blank Sample Solutions
5.1.1 Sample Solution Preparation
For plastic samples, paper, and paper products, cut or crush the sample to a maximum diameter of ≤0.5 cm. For coated, adhesive, or ink-based food contact materials and articles, scrape the dried coating, adhesive, or ink layer and grind it to a maximum diameter of ≤0.5 cm.
Weigh 1 g (accurate to 0.1 g) of the crushed sample into a headspace vial. Add 10.0 mL of N,N-dimethylacetamide, immediately cap and seal the vial, shake to dissolve or thoroughly disperse the sample, and place it in the headspace autosampler for analysis.
5.1.2 Preparation of Blank Sample Solution
Follow steps 5.1.1 except omit sample addition. Prepare the blank sample solution and place it in the headspace autosampler for analysis. Note: Due to the strong volatility of the target compound, avoid prolonged grinding in room-temperature equipment without refrigeration, which may cause sample heating and result in volatilization loss of the target compound.
5.2 Instrument Reference Conditions
5.2.1 Headspace reference conditions are as follows:
a) Dosing loop: 1 mL or 3 mL;
b) Equilibration temperature: 80 °C;
c) Dosing loop temperature: 90 °C;
d) Transfer line temperature: 100 °C;
e) Equilibration time: 30 min;
f) Pressurization time: 0.20 min;
g) Injection port filling time: 0.10 min;
h) Injection port equilibration time: 0.10 min;
i) Injection time: 1.50 min.
