GB/T 29493.4-2023 Determination of harmful substances in textile dyeing and finishing auxiliaries - Part 4: Determination of polycyclic aromatic hydrocarbons (PAHs)
WARNING - Persons using this document shall be familiar with normal laboratory practice. This document does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions.
1 Scope
This document describes a method for the determination of polycyclic aromatic hydrocarbons (PAHs) in textile dyeing and finishing auxiliaries by gas chromatography-mass spectrometry (GC-MS).
This document is applicable to the determination of 24 PAHs in textile dyeing and finishing auxiliaries (see Annex A).
2 Normative references
The following documents contain requirements which, through reference in this text, constitute provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 8170-2008 Rules of rounding off for numerical values & expression and judgment of limiting values
3 Terms and definitions
No terms and definitions are listed in this document.
4 Principle
The PAHs in the specimen are extracted by ultrasonic method using toluene, then determined by Gas Chromatograph-Mass Spectrometer, and finally quantified by the internal standard method.
5 Reagents or materials
Unless otherwise specified, only reagents confirmed to be analytically pure shall be used.
5.1 Toluene.
5.2 PAH standard substances: No.9, No.11, No.21~24 in Table A.1, each with a purity (mass fraction) ≥ 99%.
5.3 Internal standard substances: With a purity (mass fraction) ≥ 99%, as shown in Table A.2.
5.4 Standard stock solutions of 18 PAHs (see No.1~8, No.10 and No.12~20 in Table A.1) (1,000mg/L): Commercially available standard substances.
Note: Please refer to relevant certificates for the storage environment and shelf life of commercial standard substances.
5.5 Single element standard stock solutions of 6 PAHs (see, No.9, No.11 and No.21~24 in Table A.1) (1,000mg/L): Prepared by accurately weighing out 10mg (accurate to 0.1mg) of 1-methylpyrene, cyclopentene[c, d]pyrene, dibenzo[a, l]pyrene, dibenzo[a, e]pyrene, dibenzo[a, i]pyrene and dibenzo[a, h]pyrene respectively, then dissolving them in toluene (5.1) to 10mL, and mix them evenly respectively.
Note: The respective single element standard stock solutions of 6 PAHs shall be stored at 0℃~4℃ away from light, with a shelf life of 12 months.
5.6 Primary mixed standard intermediate solution of PAHs: Prepared by accurately transferring 100μL of standard stock solutions of 18 PAHs (see 5.4), and single element standard stock solutions of 1-methyl pyrene and cyclopentene[c, d]pyrene (see 5.5), 400μL of single element standard stock solutions of dibenzo[a, l]pyrene, dibenzo[a, e]pyrene, and dibenzo[a, i]pyrene and dibenzo[a, h]pyrene (see 5.5), respectively, into a 10mL volumetric flask, and diluting them with toluene (5.1) to scale respectively, with dibenzo[a, l]pyrene, dibenzo[a, e]pyrene, dibenzo[a, i]pyrene and dibenzo[a, h]pyrene at a mass concentration of 40mg/L, and the remaining 20 PAHs at a mass concentration of 10mg/L.
Note: The primary mixed standard intermediate solution of PAHs shall be stored at 0℃~4℃ away from light, with a shelf life of 3 months.
5.7 Secondary mixed standard intermediate solution of PAHs: Prepared by accurately transferring 1mL of the primary mixed standard intermediate solution of PAHs (see 5.6) into a 10mL volumetric flask, diluting it with toluene (5.1) to scale, and mix the resultant solution evenly, with dibenzo[a, l]pyrene, dibenzo[a, e]pyrene, dibenzo[a, i]pyrene and dibenzo[a, h]pyrene at a mass concentration of 4mg/L and the remaining 20 PAHs at a mass concentration of 1mg/L.
Foreword II
Introduction IV
1 Scope
2 Normative references
3 Terms and definitions
4 Principle
5 Reagents or materials
6 Apparatus
7 Test steps
8 Test data processing
9 Lower determination limit, recovery rate and precision
10 Test report
Annex A (Informative) Basic information of PAHs and internal standards tested in this document
Annex B (Informative) Quantitative and qualitative ionic information of PAHs and internal standards
Annex C (Informative) GC-MS total ion flow chromatogram of PAHs and internal standards
