Toxicological Risk Assessment of Photopolymer Constituents and Leachables: Exposure, Hazard, Read-Across and Margin of Safety

Toxicological risk assessment of a photopolymer device asks whether exposure to each relevant constituent or leachable can cause appreciable harm in the intended clinical use. The answer cannot be inferred from resin identity, an analytical pass/fail label or a single toxicity database entry. It requires a frozen finished-device state, exposure magnitude and duration, chemical identity confidence, endpoint- specific hazard evidence, route and population relevance, transparent uncertainty factors and explicit treatment of data gaps. This review defines a reproducible assessment architecture aligned with ISO 10993-17:2023 and its 2025 amendment. It separates measured quantity from patient exposure, uses a tiered hierarchy for point-of-departure selection, constrains read-across through structural, metabolic and toxicodynamic similarity, and expresses systemic or local risk with endpoint-appropriate tolerable exposure and margin-of-safety calculations. Threshold-of-toxicological-concern screening is limited by its domain and exclusions; mixture, genotoxicity, carcinogenicity, reproductive toxicity and local-contact hazards are not collapsed into one scalar. Non-compensatory gates preserve uncertainty and route unresolved constituents to additional chemistry, targeted toxicology, process control or biological evidence. No proprietary composition or product-specific acceptance limit is disclosed.

ER-254 · Version 0.4.