When this test applies
Required for devices with prolonged or long-term contact, and wherever the chemistry raises a genotoxic concern that cannot be closed out on the available data. Under ISO 10993-1:2025 the genotoxicity endpoint can often be addressed by chemical characterisation and toxicological risk assessment instead of testing — which is why it is worth asking before you commission it.
When to run it
After chemical characterisation, not before. If extractables and leachables plus an ISO 10993-17 assessment close the endpoint out, you have avoided a 6–7 week study. If they do not, the chemistry tells you what you are looking for.
What a pass tells you
That across five concentrations, with and without S9 metabolic activation, there was no concentration-related, reproducible increase in revertant colonies — a negative, non-mutagenic result for gene mutation in bacteria.
What it does not tell you
Ames covers gene mutation only. Chromosomal damage and mammalian cell mutation are separate endpoints with separate assays — chromosomal aberration and mouse lymphoma respectively — and ISO 10993-3 generally expects the battery, not a single assay. A negative Ames alone does not close genotoxicity.
Method
Testing per ISO 10993-3:2014, following OECD 471. Two extracts are prepared at 25 mL per extract, using the ISO 10993-12 ratios: 6 cm2/mL for material under 0.5 mm thick, 3 cm2/mL at 0.5 mm or thicker, or 0.1–0.2 g/mL where surface area is indeterminate. Each extract is tested against bacterial strains at five concentrations, with and without S9 metabolic activation, and revertant colonies are counted against concurrent controls. Turnaround 6–7 weeks.
Where it runs
This method is internationally sourced. The laboratory is ISO/IEC 17025 accredited and GLP certified, and the report is issued under Groenakker’s ISO 13485:2016 certified quality system, in your document format.
Usually ordered alongside
Chromosomal aberration and mouse lymphoma complete the ISO 10993-3 battery. Chemical characterisation and an ISO 10993-17 risk assessment are the alternative route and should be considered first.
