1 适用范围

本方法规定了化妆品中环氧乙烷（CAS号：75-21-8）和甲基环氧乙烷（CAS号：75-56-9）的顶空气相色谱-氢火焰离子化检测器的检测方法及顶空气相色谱-质谱的阳性确证方法。

本方法适用于清洁类和其他可能以聚乙二醇、聚丙二醇类结构的物质为原料的液体类化妆品中环氧乙烷和甲基环氧乙烷含量的测定。

2 方法提要

试样中的环氧乙烷和甲基环氧乙烷通过顶空进样系统加热后变成气态游离出来，经顶空进样进入气相色谱系统分离，采用氢火焰离子化检测器进行检测，以保留时间定性，外标法定量。本方法中环氧乙烷和甲基环氧乙烷的检出限分别为0.05 μg和0.025 μg，环氧乙烷和甲基环氧乙烷定量下限分别为0.17 μg和0.083 μg。若取2.0g样品，环氧乙烷和甲基环氧乙烷的检出浓度分别为0.025 μg/g和0.0125 μg/g，环氧乙烷和甲基环氧乙烷低定量浓度分别为0.085 μg/g和0.042 μg/g。

3 试剂和材料

除另有规定外，所用试剂均为分析纯，水为去离子水。

3.1 氯化钠。

3.2 环氧乙烷标准物质：气态，纯度≥95%。

3.3 甲基环氧乙烷标准物质：纯度≥95%。

3.4 环氧乙烷标准储备液（2.0 mg/mL～6.0 mg/mL）:量取50 mL去离子水于50 mL样品瓶（4.5）中，准确称重（记为M1，单位为g，精确0.1 mg），使用气密针（4.7）向水中通入适量环氧乙烷（3.2）气体，使其加入量在0.1 g～0.3 g之间，立即密封，涡旋混匀后，静置并准确称重（记为M2，单位为g，精确0.1 mg）。计算环氧乙烷标准储备液的实际浓度C（）。溶液应于4℃避光密封储存，有效期为二个月。

3.5 甲基环氧乙烷标准储备液（1.0 mg/mL）：称取50 mg（精确0.01 mg）甲基环氧乙烷（3.3）于预先盛有30 mL水的50 mL容量瓶中,摇匀，用水定容。计算甲基环氧乙烷标准储备液的实际浓度。溶液应于4℃避光密封储存，有效期为二个月。

3.6 环氧乙烷、甲基环氧乙烷系列浓度标准曲线：分别取5个含5 mL去离子水的顶空瓶（4.6），分别加入一定量的环氧乙烷（3.4）和甲基环氧乙烷储备液（3.5），使之分别含有环氧乙烷5 μg、10 μg、25 μg、50 μg、100 μg和甲基环氧乙烷2.5 μg、5 μg、12.5 μg、25 μg、50 μg，涡旋混匀2min，配制成系列标准溶液。


名称：毛细管柱
型号：HH-624（6%氰丙基苯基-94%甲基聚硅氧烷）
规格：30m*0.53mm*3.0um
zui高温度：260°C


化妆品中环氧乙烷和甲基环氧yi烷测定  测试谱图：



Determination of Ethylene Oxide and Methyl Oxide in Cosmetics
Determination of Ethylene Oxide and Methyl Oxide in Cosmetics Details:

1 Scope of application

This method specifies the headspace gas chromatography-hydrogen flame ionization detector for ethylene oxide (CAS number: 75-21-8) and methyl ethylene oxide (CAS number: 75-56-9) in cosmetics Detection method and positive confirmation method of headspace gas chromatography-mass spectrometry.

This method is suitable for the determination of the content of ethylene oxide and methyl ethylene oxide in cleansing products and other liquid cosmetics that may be made of materials with polyethylene glycol and polypropylene glycol structures as raw materials.

2 Method summary

The ethylene oxide and methyl oxirane in the sample are heated by the headspace sampling system and then become gaseous and liberated, and then enter the gas chromatographic system for separation through the headspace sampling. The hydrogen flame ionization detector is used for detection. Qualitative by retention time and quantification by external standard method. The detection limits of ethylene oxide and methyl oxirane in this method were 0.05 μg and 0.025 μg, respectively, and the lower quantitative limits of ethylene oxide and methyl oxirane were 0.17 μg and 0.083 μg, respectively. If a 2.0g sample is taken, the detected concentrations of ethylene oxide and methyl oxirane are 0.025 μg/g and 0.0125 μg/g, respectively, and the minimum quantitative concentrations of ethylene oxide and methyl oxirane are 0.085, respectively. μg/g and 0.042 μg/g.

3 Reagents and materials

Unless otherwise specified, the reagents used are all analytically pure, and the water is deionized water.

3.1 Sodium chloride.

3.2 Ethylene oxide standard material: gaseous, purity ≥95%.

3.3 Methyl oxirane standard material: purity ≥95%.

3.4 Ethylene oxide standard stock solution (2.0 mg/mL～6.0 mg/mL): Measure 50 mL deionized water into a 50 mL sample bottle (4.5), and accurately weigh it (denoted as M1, unit is g, accurate To 0.1 mg), use an air-tight needle (4.7) to infuse an appropriate amount of ethylene oxide (3.2) gas into the water to make the added amount between 0.1 g and 0.3 g, seal it immediately, vortex and mix, and then stand still And weigh accurately (denoted as M2, unit is g, accurate to 0.1 mg). Calculate the actual concentration C() of the ethylene oxide standard stock solution. The solution should be sealed and stored at 4°C and protected from light. The validity period is two months.

3.5 Methyl oxirane standard stock solution (1.0 mg/mL): Weigh 50 mg (accurate to 0.01 mg) of methyl oxirane (3.3) into a 50 mL volumetric flask pre-filled with 30 mL water, Shake well and make up to volume with water. Calculate the actual concentration of the methyl oxirane standard stock solution. The solution should be sealed and stored at 4°C and protected from light. The validity period is two months.

3.6 The concentration standard curve of ethylene oxide and methyl ethylene oxide series: Take 5 headspace bottles (4.6) containing 5 mL of deionized water respectively, and add a certain amount of ethylene oxide (3.4) and methyl oxide respectively. Ethylene oxide stock solution (3.5), which contains 5 μg, 10 μg, 25 μg, 50 μg, 100 μg of ethylene oxide and 2.5 μg, 5 μg, 12.5 μg, 25 μg of methyl oxirane, respectively , 50 μg, vortex and mix for 2 minutes to prepare a series of standard solutions.


Name: Capillary Column
Model: HH-624 (6% cyanopropyl phenyl-94% methyl polysiloxane)
Specification: 30m*0.53mm*3.0um
Maximum temperature: 260°C


Determination of ethylene oxide and methyl oxirane in cosmetics Test spectrum: