ISO 19609-4:2022 PDF

Overview

ISO 19609-4:2022 - Traditional Chinese medicine: Quality and safety of raw materials and finished products - Part 4: Testing for preservatives and unwanted compounds - specifies analytical approaches and quality-control requirements for detecting preservatives and unwanted compounds in raw materials and finished traditional Chinese medicine (TCM) products. The standard is part of the ISO 19609 series and guides laboratories and manufacturers on screening, quantitative testing and declaration of contaminants such as sulfur derivatives, ethylene oxide, irradiated material and toxic degradation products.

Key technical topics and requirements

• Scope: Defines testing within a risk‑assessment framework for starting materials and finished TCM products.
• Categories of unwanted compounds: preservatives, radiation (irradiated materials), toxic compounds (natural toxins and degradation products) and other additives.
• Declaration: Preservatives must be declared on product labels or Certificates of Analysis (CoA).
• Sulfur and sulfur derivatives:
  • Elemental sulfur screening: sample washing, filtration and drying; heating residue to detect characteristic gas/odour.
  • Quantification of sulfur derivatives as sulfur dioxide: apply ISO 22590 or equivalent validated methods.
  • Quick qualitative screening: lead‑acetate test after acid/zinc treatment; sample milled