Medical Device Biological Evaluation & ISO 10993 Testing

Biological evaluation is a risk-based assessment of whether a device's materials, as processed and sterilised, are acceptable for its intended body contact — not a fixed list of tests. The ISO 10993 family is a set of separate standards covering the evaluation process and individual endpoints, and which of them apply depends on the device.

Start with the biological evaluation plan

Identify direct and indirect body contact, tissue category, duration, finished materials, manufacturing and sterilization residues, and changes from existing evidence. A qualified evaluator decides which endpoints need evidence and whether existing data, chemical characterization or targeted testing can address them. No-contact products and some supported material histories may need different evidence; every device does not need every endpoint.

FDA recognition and guidance status

ISO 10993-1:2025 has partial FDA recognition with exceptions. Declarations to the 2018 edition are accepted for premarket submissions until July 1, 2029; this is a transition, not automatic retesting of all legacy devices. FDA's September 2023 risk-based guidance remains final. Confirm the recognized provisions and evidence needed for the specific submission.

What to include in your buyer brief

Start with the decision the work must support. Unknown details can be clarified after the initial inquiry.

Product, materials/formulation, patient or drug contact, contact duration, intended use and target market; identify changed materials, suppliers or processes.
Finished configuration, sample count and lots, sterilization modality/cycles, aging and storage history; justify worst-case variants and destructive allocations.
Existing evaluation plan, drawings, specifications, methods/editions, previous reports and acceptance criteria; send confidential files only through the private intake.
Required report, quality/accreditation scope, budget range, location, shipping constraints and decision deadline; ask the provider to explain exclusions and subcontracted work.

Reference versus candidate medical plastics and colorants

Compare the reference and candidate finished components, documented resin identity when available, pigment/dye or additive changes, manufacturing and cleaning/sterilization histories, and actual exposure. Unknown composition, sample allocation and test panels remain questions to resolve—not inferred facts. Material identification and color comparison do not establish biological safety.

Propose methods around the evidence gap

Ask the provider whether FTIR, DSC or other material identification, targeted chemistry, extraction studies and toxicological interpretation can answer the comparison question. These are possible proposals, not prescribed tests. Biological compatibility, chemical/material resistance and product interactions are different scopes. A qualified evaluator should justify existing evidence, chemical characterization and any targeted biological testing after a material or colorant change.

Plan, evaluate and test: separate the deliverables

A biological evaluation plan (BEP) identifies contact, duration, existing evidence and gaps; a biological evaluation report (BER) integrates the evidence and rationale. An endpoint laboratory report answers a scoped test question, not the entire biological evaluation. A qualified evaluator should justify endpoint selection and use of prior evidence; not every material change requires every test.

Chemistry versus toxicological interpretation

ISO 10993-18 chemical characterization addresses what substances may be present or released and the analytical coverage/limitations. ISO 10993-17 toxicological risk assessment interprets constituent exposure, toxicological evidence and uncertainty in the device-use context. A chemical list alone is not a safety conclusion, and a TRA cannot cure poorly justified extraction or uncharacterized analytical gaps.

Extractables, leachables and residuals

Forced extractables explore potential release under justified exaggerated conditions; actual or simulated-use leachables address release under relevant contact conditions. Neither automatically substitutes for the other. Distinguish manufacturing residuals such as monomers, solvents and processing aids from sterilization residuals such as ethylene oxide and relevant reaction products. Define analytical targets, exposure assumptions, recovery, reporting thresholds and uncertainties with the provider; no universal panel.

Sample considerations

Provide final, finished, sterilised devices where the evaluation expects them — testing raw material rarely substitutes.
State contact type (surface, external communicating, implant) and contact duration, because these drive which endpoints are considered.
Supply the full material and processing picture: resins, additives, colourants, adhesives, coatings, lubricants, cleaning agents and sterilisation method.
Send enough devices for the endpoints in scope plus retains; quantities are usually larger than expected.

Laboratories with relevant capabilities

Medical Engineering Technologies (MET) (Dover, Kent) — documented: Biological evaluation plans
Eurofins Medical Device Testing Munich (Planegg, Bavaria) — documented: ISO 10993 biological evaluation
Charles River Laboratories (Mattawan, MI) — documented: ISO 10993 biological evaluation
WuXi AppTec Medical Device Testing (Suzhou, Jiangsu) — documented: In vivo and in vitro biological evaluation

Frequently asked questions

What is the difference between biological evaluation and biocompatibility testing?: Biological evaluation is the overall risk-based assessment of a device's biological safety. Biocompatibility testing is one possible source of evidence within it. Each relevant endpoint is addressed with existing data, chemical characterisation and toxicological risk assessment, testing, or a documented scientific justification — testing is not automatically required for every endpoint. FDA's Biocompatibility Assessment Resource Center (fda.gov) and its recognized consensus standards list are the authoritative US references. Use the questionnaire at /industries/medical-devices/what-testing-does-my-device-need to organise your inputs.
Is ISO 10993 a single test?: No. It is a family of separate standards. One part sets out the evaluation and testing process within a risk management framework, and other parts address individual matters such as cytotoxicity, genotoxicity, sensitisation, irritation and chemical characterisation. Which parts are relevant depends on the device, its materials, and the nature and duration of body contact.
Which tests will my device need?: That comes out of the evaluation, not from a standard checklist. A device with brief intact-skin contact and an implanted device are treated very differently. Describe the device and contact scenario and laboratories can propose a scope.
Can chemical characterisation reduce biological testing?: In many programmes, chemical characterisation combined with toxicological risk assessment addresses endpoints that would otherwise require biological testing. Whether it is accepted depends on the device, the data quality and the requirement you are working to.
Does a material change mean starting over?: Not necessarily, but it does mean revisiting the evaluation. A change in resin grade, colourant, adhesive, supplier or sterilisation method can change what is released from the device.
What quality system should the laboratory have?: It varies by endpoint and by submission. Ask each laboratory which quality system, accreditations and study conduct apply to the specific tests you need, and confirm it in writing before work starts.