Ethylene Oxide Sterilisation of Single-Use Medical Devices: Process Validation under ISO 11135 and Residuals under ISO 10993-7 — A Structured Narrative Review

Background: Ethylene oxide (EtO) is the main low-temperature sterilant for single-use polymer devices such as tubing, catheters and drains. Its use depends on a validated process (ISO 11135) and on control of residual EtO and ethylene chlorohydrin (ISO 10993-7), while EtO is also a genotoxic carcinogen, an allergen and a regulated emission. Methods: Five PubMed/MEDLINE searches (NCBI E-utilities, 11 November 2026; publication dates 1980 to October 2026) covered process validation, residuals and aeration, hypersensitivity, toxicology and exposure, and alternative modalities. 982 records (894 unique) were screened; 94 reports were included and every reference was checked against PubMed and Crossref. Results: Temperature, gas concentration and humidity jointly determined lethality. Overkill half-cycle validation is conservative, and exposure time, residuals and sterilant use can be reduced; parametric release is increasingly used. Residuals depended on polymer and wall thickness: silicone tubing absorbed 85% less EtO than PVC or polyether-polyurethane and desorbed faster. EtO sensitisation was frequent in repeatedly exposed groups (23% of children with myelomeningocele; 55% of dialysis patients with previous reactions). Cancer evidence is contested but EtO is classified as carcinogenic to humans. X-ray, vaporised hydrogen peroxide, nitrogen dioxide and supercritical CO2 are maturing alternatives. Conclusions: EtO remains necessary for many polymer devices; safe use needs optimised validated cycles, material-aware aeration and residual testing, and attention to sensitised patients, workers and communities. Company information: https://sybariatric.com