Overview
EN ISO 10993-18:2020/A1:2023 is the CEN-adopted amendment to ISO 10993-18 (Part 18 of the ISO 10993 series) that updates guidance on chemical characterization of medical device materials within a risk management process, with a specific focus on the determination of the uncertainty factor. The amendment clarifies editorial items, refines examples and tables, and provides additional detail on solvent/anti‑solvent guidance and quantification approaches used in extractables and leachables (E&L) profiling. This standard supports biological evaluation and is intended to be used alongside EU medical device requirements (Regulation (EU) 2017/745).
Key Topics
- Scope: Chemical characterization as part of biological evaluation and risk management for medical devices (qualitative and quantitative characterization, E&L profiling).
- Uncertainty factor: Guidance to determine and apply an uncertainty factor when estimating concentrations and exposure from analytical data.
- Analytical methods: Classification of methods as qualitative or quantitative (e.g., HPLC with UV, CAD, ELSD and/or MS marked for both qualitative and quantitative use in the amendment).
- Data reporting and quantification: Clarified expectations for quantification accuracy, including the use and limitations of surrogate standards and reporting of estimated concentrations.
- Appendices corrections: Edits to appendix content (solvent polarity/mole fraction definitions, updated solvent abbreviations, anti‑solvent recommendations for certain polymers).
- Limitations noted: The standard does not cover ADME, particles/wear debris, packaging, flammability or transport/storage contaminant aspects (as referenced in the Annex ZA mapping to EU MDR).
Applications
Who uses this standard and why:
- Medical device manufacturers - to perform chemical characterization and justify biocompatibility assessments and material specifications.
- Regulatory affairs teams - to compile technical files and demonstrate conformity with EU MDR General Safety and Performance Requirements.
- Analytical chemists and toxicologists - to design and interpret extractables/leachables studies, estimate exposures, and apply appropriate uncertainty factors.
- Quality & risk managers - to integrate chemical data into ISO 14971-based risk management and decision making.
- Notified bodies and auditors - to assess whether chemical characterization supports biological safety claims.
Practical uses include selection of analytical approaches, establishing reporting and quantification practice for E&L studies, deriving conservative exposure estimates, and supporting biocompatibility conclusions.
Related Standards
- ISO 10993-1 - Biological evaluation within a risk management process
- ISO 10993-17 - Establishment of allowable limits for leachable substances
- ISO 14971 - Application of risk management to medical devices
- Regulation (EU) 2017/745 (MDR) - Standard supports conformity to relevant General Safety and Performance Requirements
Keywords: EN ISO 10993-18:2020/A1:2023, chemical characterization, medical devices, uncertainty factor, extractables and leachables, biocompatibility, risk management, EU MDR.
