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 worth asking before commissioning it. This is the clastogenicity arm of the ISO 10993-3 battery — damage at the chromosome level, which the bacterial reverse mutation assay cannot see.
When to run it
After chemical characterisation, not before. If extractables and leachables plus an ISO 10993-17 assessment close the endpoint out, the study is avoided entirely. If they do not, the chemistry tells the laboratory what it is looking for.
What a pass tells you
That neither extract produced a statistically significant, dose-related increase in structural chromosomal aberrations relative to the concurrent negative control, with the positive controls responding as expected. That last clause matters: without a responding positive control the study is uninterpretable rather than negative.
What it does not tell you
It covers structural chromosome damage. Gene mutation in bacteria (Ames) and mammalian cell mutation (mouse lymphoma) are separate endpoints with separate assays. ISO 10993-3 generally expects a battery rather than a single assay, so no one result closes genotoxicity on its own.
Method
Testing per ISO 10993-3:2014. Two extracts are prepared, one polar and one non-polar, and dosed onto mammalian cells in culture; structural chromosomal aberrations are scored against concurrent negative and positive controls. Extraction ratio follows ISO 10993-12: 6 cm²/mL for material under 0.5 mm thick, 3 cm²/mL at 0.5 mm or thicker, or 0.1 to 0.2 g/mL where surface area is indeterminate.
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 cover, in Groenakker’s report template or in your document template on request at no extra cost.
Usually ordered alongside
The bacterial reverse mutation assay (Ames) and the mouse lymphoma assay complete the ISO 10993-3 battery. Chemical characterisation with an ISO 10993-17 assessment is the alternative route and should be considered first.
