ISO 17075-2:2017

Overview - ISO 17075-2:2017 (Leather, Chromatographic method for chromium(VI))

ISO 17075-2:2017 specifies a laboratory chromatographic method for the chemical determination of chromium(VI) in solutions leached from leather under defined extraction conditions. The method uses ion-exchange chromatography (HPLC or ion chromatograph with UV/VIS detection) to quantify extractable Cr(VI) down to 3 mg/kg (expressed as mg Cr(VI) per kg dry leather). Results are strictly dependent on the prescribed extraction conditions (phosphate buffer at pH 7.0–8.0, defined extraction time and agitation) and are considered the reference if a sample is tested with both ISO 17075-1 and ISO 17075-2.

Key topics and technical requirements

• Scope and applicability
  • Applicable to all leather types for determining extractable chromium(VI).
• Extraction conditions
  • Leaching in phosphate buffer at pH 7.0–8.0 with defined sample mass, extraction volume and shaking time - results are not comparable if different extraction procedures are used.
• Chromatographic determination
  • Ion-exchange chromatography with UV/VIS detection (HPLC or ion chromatograph). Annexes provide example conditions:
    • Direct detection of chromate (example peak at ~372 nm).
    • Post-column reaction with 1,5-diphenylcarbazide (example detection at ~540 nm).
• Calibration and quantification
  • External standard calibration using multiple calibration levels; injection volumes and peak areas are recorded for quantification.
• Recovery and method verification
  • Mandatory recovery-rate check (matrix spike) to assess matrix effects. Acceptable recovery range: 80–120%.
• Sensitivity
  • Method suitable to quantify Cr(VI) down to 3 mg/kg.
• Reporting
  • Procedures for calculation, expression of results and test reporting are specified.

Practical applications - who uses ISO 17075-2

• Leather testing laboratories and QA/QC labs validating Cr(VI) content in raw or finished leathers.
• Tanneries and leather manufacturers monitoring tanning processes and product safety.
• Product safety and compliance teams using standardized analytical results for internal control or to demonstrate due diligence.
• Footwear, apparel and upholstery manufacturers who need reliable analytical data for material selection and supplier verification.
• Useful where sample extracts are strongly coloured, since the chromatographic approach avoids colour interferences that can affect colorimetric assays.

Related standards

• ISO 17075-1 - Colorimetric method for chromium(VI) in leather (ISO 17075-2 results are the reference when both are applied).
• Sampling and sample preparation standards referenced in ISO 17075-2:
  • ISO 2418 (sampling location), ISO 4044 (preparation of chemical test samples), ISO 3696 (water quality).

Keywords: ISO 17075-2:2017, chromium(VI), leather testing, chromatographic method, ion-exchange chromatography, Cr(VI) content, extraction conditions, recovery rate, HPLC detection.