GB 31604.28-2016

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GB 31604.28-2016	English	85	Add to Cart	0--3 minutes. Auto-delivered.	National Food Safety Standard -- Food contact materials and products -- Determination of di (2-ethylhexyl) adipate and migration	GB 31604.28-2016	Valid	GB 31604.28-2016

GB 31604.28-2016
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
National Food Safety Standard -
Food contact materials and products -
Determination of di (2-ethylhexyl) adipate and migration
ISSUED ON. OCTOBER 19, 2016
IMPLEMENTED ON. APRIL 19, 2017
Issued by. National Health and Family Planning Commission of People's
Republic of China
Table of Contents
Foreword ... 3
1 Scope ... 4
Determination of di (2-ethylhexyl) adipate (DEHA) ... 4
2 Principle... 4
3 Reagents and materials ... 4
4 Instruments and equipment ... 5
5 Analytical steps ... 6
6 Expression of the analytic result ... 8
7 Precision... 8
8 Others ... 8
Determination of di (2-ethylhexyl) adipate (DEHA) migration ... 9
9 Principle... 9
10 Reagents and materials... 9
11 Instruments and equipment ... 11
12 Analytical steps ... 11
13 Expression of the analytic result ... 13
14 Precision ... 13
15 Others ... 14
Appendix A Total ion flow chromatogram and mass spectrogram of standard
solution ... 15
Foreword
This standard replaces GB/T 20499-2006 "Method for the determination of di
(2-ethylhexyl) adipate migrating from polyvinyl chloride film in contact with
foodstuffs", “Method for the determination of di (2-ethylhexyl) adipate” in GB/T
20500-2006 “Method for the determination of di (2-ethylhexyl) adipate and
di-n-octyl adipate in polyvinyl chloride film” and “Method for the determination
of di (2-ethylhexyl) adipate migration” in SN/T 2826-2011 “Food contact
materials for export. Polymers. Determination of adipate plasticizers in food
stimulants. Gas chromatography-mass spectrometry”.
The main differences of this standard in comparison with GB/T 20499-2006
and GB/T 20500-2006 are as follows.
- Changed the name of the standard to "National Food Safety Standard -
Food contact materials and products - Determination of di (2-ethylhexyl)
adipate and migration";
- Deleted the gas chromatography-mass spectrometry for determination of
di (2-ethylhexyl) adipate.
National Food Safety Standard - Food contact materials
and products - Determination of di (2-ethylhexyl) adipate
and migration
1 Scope
This standard specifies the methods of determination of di (2-ethylhexyl)
adipate (DEHA) and migration in food contact materials and products.
This standard is applicable to the determination of di (2-ethylhexyl) adipate
and migration in polyvinyl chloride products.
Determination of di (2-ethylhexyl) adipate (DEHA)
2 Principle
Dissolve the sample with tetrahydrofuran and precipitate the polymer by
methanol. After filtration, DEHA remains in the filtrate. Determine by gas
chromatography-mass spectrometer and quantify by external standard
method.
3 Reagents and materials
3.1 Reagent
Unless otherwise stated, the reagents used in this method shall be analytical
pure. The water shall be the primary water specified in GB/T 6682.
3.1.1 Tetrahydrofuran (C4H8O, CAS No..109-99-9)
3.1.2 Methanol (CH4O,CAS No..67-56-1)
3.1.3 N-hexane (C6H12,CAS No..110-54-3). Chromatographic pure
3.2 Standard product
di (2-ethylhexyl) adipate (C22H42O4, CAS No.. 103-23-1). purity≥99.8%, or a
standard substance certified by the State and granted the standard
The mass spectrum conditions are as follows.
a) Mass spectrum interface temperature. 250°C;
b) Temperature of ion source. 250°C;
c) Ionization mode. EI;
d) Ionization energy. 70 eV;
e) Determination method. select the ion monitoring mode, the monitoring
ion range(m/z) of DEHA. 40~370, the DEHA characteristic ions of are.
129, 147, 112, 71, of which 129 is quantitative ion;
f) Solvent delay by. 5 min.
5.5 Making of standard curve
According to the determination conditions listed in 5.4, inject the standard
working solution (3.3.3) into the gas chromatography-mass spectrometer in
turn. The standard curve was drawn with the concentration of the standard
working solution as the horizontal coordinate with the unit of mg per liter
(mg/L), and the corresponding peak area of DEHA as the vertical coordinate.
See figure A.1. for a standard chromatogram.
5.6 Determination of sample solution
5.6.1 Qualitative determination
In accordance with the determination conditions listed in 5.4, inject the
sample solution (5.2) and the blank solution (5.3) into the gas
chromatography-mass spectrometer for determination. When determine the
sample under the same experimental conditions, if the deviation of the
chromatographic peak retention time of the substance to be determined in the
sample solution is within ±2.5% of the chromatographic peak retention time of
the standard substance; and all the selected ions appear in the sample mass
spectrometry after background subtraction; and the deviation of the relative
abundance of the qualitative ion in the sample spectrum compared with the
relative abundance of the qualitative ion in the standard solution with similar
concentration does not exceed the range specified in Table 1, then it can be
determined that there is such substance in the sample. The characteristic
ions and their abundance ratios of DEHA are shown in Table 2. For DEHA
chromatogram see figure A.2.
Table 1 -- Maximum allowable deviation of relative ion abundance in
qualitative confirmation
Relative ion abundance K /% >50 20~50 10~20 ≤10
DEHA concentration of 2mg/mL is obtained. Store the solution in the
refrigerator for validity period of 1 month.
10.4.2 DEHA standard intermediate solution (Water, acidic, alcohol
based food simulants analysis)
Draw 2.5mL DEHA standard reserve solution (10.4.1) with graduated pipette
to 50mL volumetric bottle, dilute to the scale with n-hexane. The standard
intermediate solution of DEHA is obtained with the concentration of
100.0mg/L. The storage method of the solution is the same as that of 10.4.1.
10.4.3 DEHA standard working solution (for water, acidic, alcohol based
food simulants analysis)
Draw with graduated pipette and micro-syringe respectively 50μL, 0.2mL,
0.5mL, 1.0mL, 2.0mL, 5.0mL of the DEHA standard intermediate solution
(10.4.2), place them in 6 10mL volumetric bottles, dilute with n-hexane, meter
the volume and shake to mix well. The standard working solution of DEHA is
obtained with concentration of 0.5mg/L, 2.0mg/L, 5.0mg/L, 10.0mg/L,
20.0mg/L, 50.0mg/L. The storage method is the same as that of 10.4.1.
10.4.4 DEHA standard reserve solution (for oil-based food simulants
analysis)
Weigh DEHA 50mg (precision to 0.0001g) and put it into the 50mL beaker.
Add oil-based food simulant 50g (precision to 0.0001g), dissolve and mix
evenly. The concentration of the standard reserve solution is 1000mg/kg.
Store the solution in the refrigerator for validity period of 1 month.
10.4.5 DEHA standard intermediate solution (for oil-based food
simulants analysis)
Weigh 1.0g (precision to 0.01g) of DEHA standard reserve solution (10.4.4),
put into the 10mL volumetric bottle. Weigh accurately 9.0g (precision to
0.0001g) of oil-based food simulant and put into the same bottle. Mix to obtain
the DEHA standard intermediate solution with the concentration of 100mg/kg.
The storage method of the solution is the same as that of 10.4.4.
10.4.6 DEHA standard working solution (for oil-based food simulants
analysis)
Weigh respectively 0.2g, 0.5g, 1.0g, 2.0g, 4.0g, 5.0g (precision to 0.01g) of
the DEHA standard intermediate solution (10.4.5), place them into 6 10mL
volumetric bottles, add respectively 9.8g, 9.5g, 9.0g, 8.0g, 6.0g, 5.0g
(precision to 0.0001g) of oil-based food simulant, shake to mix and obtain the
standard working solution of DEHA with concentration of 2mg/kg, 5mg/kg,
10mg/kg, 20mg/kg, 40mg/kg, 50mg/kg respectively. Weigh respectively the
e) Determination method. select the ion monitoring mode, the monitoring
ion range(m/z) of DEHA. 40~370, the DEHA characteristic ions of are.
129, 147, 112, 71, of which 129 is the quantitative ion;
f) Solvent delay by. 5 min.
12.5 Making of standard curve
In accordance with the determination conditions listed in 12.4, determine
respectively the water, acid, alcohol, oil-based food simulant standard
working solution (10.4.3, 10.4.6). Draw the standard curve using the DEHA
concentration in the standard working solution as the horizontal coordinate, in
unit of “milligram per liter(mg/L) (water, acid, alcohol-based food simulant), or
milligrams per kilogram (mg/kg) (oil-based food simulant)", and the peak area
of corresponding DEHA as the vertical coordinate.
12.6 Determination of sample solution
12.6.1 Qualitative determination
In accordance with the determination conditions listed in 12.4, inject the
sample solution (12.2) and the blank solution (12.3) into gas chromatography
mass spectrometer for determination. The qualitative method is the same as
5.6.1.
12.6.2 Quantitative determination
When determine the sample and blank solution, deduct the blank value to
obtain the peak area of DEHA.
13 Expression of the analytic result
Obtain the concentration of DEHA in the sample solution from the standard
curve. Calculate according to GB 5009.156 to obtain the migration amount of
DEHA in food contact materials and products. Retain two-digit valid numbers
for the results of calculation.
14 Precision
The absolute difference between the two independent measurements
obtained under repetitive conditions shall not exceed 10% of the arithmetic
average.