SN/T 5237-2020 in English

Technical background and scope of application of the standard

As a mandatory inspection procedure issued by the General Administration of Customs in 2020, this standard uses inductively coupled plasma mass spectrometer (ICP-MS) to establish a high-sensitivity analysis method for the detection of 9 extractable heavy metals such as Pb, Cd, Cr, As, Cu, Sb, Ni, Co, and Hg in textiles. Technological evolution is reflected in:

Analysis of key detection process

1. Key points of pretreatment technology

Acid sweat simulated extraction (GB/T 3922) was used: 4 g of sample was oscillated at a constant temperature of 37°C for 60 minutes, and filtered through a 0.45 μm filter membrane. It should be noted that the mercury element needs to be stabilized by adding 0.1 mL of hydrochloric acid.

2. Instrument parameter optimization

Quality control requirements

Implementation suggestions

1. Cone maintenance cycle: Ni sampling cone needs to be checked for corrosion after every 200 tests
2. Internal standard selection: For As, 72Ge is recommended instead of 103Rh (to avoid mass number interference)
3. Batch detection: insert 1 QC sample (GBW10025 standard substance) for every 10 samples