Chlorine Dioxide Medical Device Sterilization: Residual Toxicity Testing

Abstract Purpose Ethylene oxide (EtO), a commonly used sterilant for medical devices, is a known carcinogen that leaves carcinogenic residuals. Recent regulatory changes encourage medical device manufacturers to consider non-carcinogenic sterilants, including chlorine dioxide (ClO 2 ) sterilization. Although medical device manufacturers often request ClO 2 residual testing, there is a lack of literature exploring ClO 2 residual toxicity. This research bridges this gap by proposing testing criteria and assessing the toxicity of chlorite, chlorate, and chloride residuals post ClO 2 sterilization. Methods We developed criteria using data from guidelines published by the United States Environmental Protection Agency and the World Health Organization. We completed a descriptive analysis of ion chromatography testing of different medical devices sterilized by ClO 2 , including a device indicated for incidental contact, a device to treat corneal abrasions, a smoking cessation inhaler, a device to treat embolisms, polychlorotrifluoroethylene bottles, and prefilled syringes. Results Results showed that the residual levels from each device tested were below toxicity limits of < 6.83 mg/device or < 0.8 mg/L for chlorite and < 70.65 mg/device or < 0.7 mg/L for chlorate. Chloride, a naturally occurring element considered non-toxic, was not included in the analysis. Conclusion These results support ClO 2 sterilization as a viable, non-toxic alternative to EtO for medical device manufacturers and contract sterilizers. Future research is needed to determine residual toxicity criteria for high-contact medical devices intended for long-term use.