Standard No.:	GB/T 18412.4-2006
English Name:	Textiles - Determination of the pesticide residues - Part 4: Pyrethroidpesticides
Chinese Name:	纺织品 农药残留量的测定 第4部分：拟除虫菊酯农药
Chinese Classification:	W04    Basic standards and general methods
Professional Classification:	GB    National Standard
ICS Classification:	59.080.01 59.080.01     Textiles in general 59.080.01
Issued by:	AQSIQ; SAC
Issued on:	2006-5-25
Implemented on:	2006-12-1
Status:	valid
Language:	English
File Format:	PDF
Word Count:	4000 words
Price(USD):	100.0
Delivery:	via email in 1 business day

1 Scope This part of GB/T 18412 specifies the methods for the determination of 12 pyrethroid pesticides (see Annex A) residues in textiles by gas chromatography-electron capture detector (GC-ECD) and gas chromatography-mass spectrometry (GC-MS). This part is applicable to textile materials and their products. 2 Principle Extract the specimen ultrasonically by acetone-n-hexane (1+4), concentrate the extracting solution to a constant volume, and then determine it with a gas chromatography-electron capture detector (GC/ECD) and quantify by external standard method, or determine and confirm it by gas chromatography-mass spectrometry (GC-MS) and quantify by external standard method. 3 Reagents and materials Unless otherwise specified, all reagents used shall be analytically pure reagents. 3.1 Acetone: residue grade. 3.2 N-hexane: residual grade. 3.3 Anhydrous sodium sulfate: burned at 650℃ for 3 h, and then stored in desiccator for standby after cooling down. 3.4 Acetone-n-hexane (1+4). 3.5 Standard pyrethroid pesticides : purity ≥ 98%, see Annex A. 3.6 Standard stock solution: Accurately weigh an appropriate amount of each standard pyrethroid pesticide separately, and prepare standard stock solution with a mass concentration of 100 μg/mL with n-hexane. 3.7 Mixed standard working solution: Dilute the above solution with n-hexane step by step as required to form series mixed standard working solutions with applicable concentrations. Note: The validity period of the standard stock solution is 12 months in a refrigerator at 0℃ ~ 4℃, and that of the mixed standard working solution is 6 months in a refrigerator at 0℃ ~ 4℃.

Foreword 1 Scope 2 Principle 3 Reagents and materials 4 Instruments and apparatus 5 Analytical procedure 6 Calculation of results 7 Determination lower limit, recovery rate and precision 8 Test report Annex A (Normative) List of 12 pyrethroid pesticides Annex B (Informative) Quantitative and qualitative selected ions of pyrethroid pesticides and determination lower limit Annex C (Informative) Gas chromatogram (GC-ECD) of standard pyrethroid pesticides Annex D (Informative) Gas chromatogram-mass spectrogram (GC-MSD) of standard pyrethroid pesticides