Overview
EN ISO 787-28:2020 (ISO 787-28:2019) specifies a laboratory method for the determination of total polychlorinated biphenyls (PCBs) in pigment and extender materials. The procedure uses dissolution, clean-up and gas chromatography–mass spectrometry (GC‑MS) to screen and quantify all 209 PCB congeners. The method is designed for a working range of 1 mg/kg to 150 mg/kg, with a lower quantitation limit (LOQ) of 1 mg/kg per congener; results below 1 mg/kg are reported as qualitative.
Key Topics
- Scope and intent: Measures total PCB content in pigments/extenders, including PCBs occluded in crystal lattices (not just surface residues).
- Analytes covered: Complete congener list (209 PCB congeners).
- Analytical principle: Sample dissolution → extraction → multi-stage clean‑up → separation and detection by GC‑MS.
- Quantitation and references: Use of 13C-labelled internal reference materials added to the weighed sample to support accurate quantitation.
- Sample handling: Sampling referred to ISO 15528 (paints, varnishes and raw materials).
- Clean-up techniques: Multilayer column clean-up is obligatory; optional steps in the standard include diatomaceous earth–sulfuric acid columns, gel permeation (size-exclusion) chromatography, and alumina columns.
- Documentation: Procedures include preparation of GC solutions, calculation/quantitation steps and required test report content.
Applications
EN ISO 787-28:2020 is primarily used by:
- Pigment and extender manufacturers for product quality control and batch release.
- Independent analytical and contract testing laboratories performing PCB screening in raw materials.
- Purchasing and supplier‑qualification teams verifying incoming pigment consignments.
- Health, safety and compliance teams who need robust data to assess material safety and support regulatory or customer requirements.
Practical benefits:
- Detects PCBs that simple surface extraction methods can miss, providing more reliable total‑content data for pigments.
- Supports traceable, GC‑MS–based quantitation across a defined concentration range (1–150 mg/kg).
- Provides structured clean‑up workflows to minimize interferences and improve analytical accuracy.
Related Standards
- ISO 15528 - Paints, varnishes and raw materials for paints and varnishes: Sampling (referenced).
- ISO 18451-1 - Pigments, dyestuffs and extenders: Terminology - Part 1: General terms.
- Other parts of the ISO 787 series covering general test methods for pigments and extenders.
For authoritative requirements and full procedural details, consult the official EN ISO 787-28:2020 / ISO 787-28:2019 publication or your national standards body.