Ethylene oxide gas (EtO) is widely used to sterilize materials and products that would be damaged by methods involving heat, moisture or radiation. Alkylation, or the replacement of a hydrogen atom with an alkyl group, within cells prevents normal cellular metabolism and replication.877. Exposure to ETO can cause eye pain, sore throat, difficulty breathing and blurred vision. Depending on industry standards, EtO can be used to reduce or inactivate the microbial population of a product or material. Scrubbing liquid counterflows downward, through the packing, by gravity. Ambient room aeration also will achieve desorption of the toxic ETO but requires 7 days at 20°C. Comparison of the characteristics of selected chemicals used as high-level disinfectants or chemical sterilants, Table 5. These ETO models minimize potential ETO exposure during door opening and load transfer to the aerator. Saving Lives, Protecting People, Centers for Disease Control and Prevention, National Center for Emerging and Zoonotic Infectious Diseases (NCEZID), Division of Healthcare Quality Promotion (DHQP), Introduction, Methods, Definition of Terms, A Rational Approach to Disinfection and Sterilization, Factors Affecting the Efficacy of  Disinfection and Sterilization, Regulatory Framework for Disinfectants and Sterilants, Low-Temperature Sterilization Technologies, Microbicidal Activity of Low-Temperature Sterilization Technologies, Effect of Cleaning on Sterilization Efficacy, Recommendations for Disinfection and Sterilization in Healthcare Facilities, Table 1. There are no federal regulations for ETO sterilizer emission; however, many states have promulgated emission-control regulations.814, ETO is absorbed by many materials. Characteristics of an ideal low-temperature sterilization process, Table 10. These influence the effectiveness of ETO sterilization.814, 857, 858 Within certain limitations, an increase in gas concentration and temperature may shorten the time necessary for achieving sterilization. A number of investigations have shown that it will react with food constituents and disturb the nutritional value of food. Most modern ETO sterilizers combine sterilization and aeration in the same chamber as a continuous process. Linking to a non-federal website does not constitute an endorsement by CDC or any of its employees of the sponsors or the information and products presented on the website. While the obvious one is health protection, sterilization is also useful in increasing shelf life of treated materials. Factors affecting the efficacy of sterilization, Table 11. Gas from the sterilization vessels is directed to the scrubber and is channeled upward through the packed bed. The other mixture, which is a drop-in CFC replacement, is ETO mixed with HCFC. Ethylene oxide (EtO) is one of the Food and Drug Administration-approved methods for sterilization, but its effect on PVA has not been studied extensively. Guideline for Disinfection and Sterilization in Healthcare Facilities (2008). HCFCs are approximately 50-fold less damaging to the earth’s ozone layer than are CFCs. Most modern ETO sterilizers combine sterilization and aeration in the same chamber as a continuous process. Examples of flash steam sterilization parameters, Table 9. When sterilization time is complete, the gas is removed from the chamber by a vacuum pump and sent to a scrubbing system which absorbs and eliminates the EtO. In the process, intimate mixing and absorption of the gas takes place. Per 10CFR §185, the FDA has only approved ethylene oxide fumigation for raw spices, dehydrated vegetables, and spice blends which do not contain salt. ETO is a colorless gas that is flammable and explosive. CDC twenty four seven. Suggested protocol for management of positive biological indicator in a steam sterilizer, U.S. Department of Health & Human Services. Other food components such as gums, starch and nutmeats are being routinely sterilized for increased safety and extended shelf life of the ingredient or the final food product. about cosmed group. You will be subject to the destination website's privacy policy when you follow the link. The 100% ETO sterilizers using unit-dose cartridges eliminate the need for external tanks. The outcome of this study provides the effects of EtO and γ-irradiation of PVA grafts on both the material properties and the in vivo responses, particularly for vascular applications. Typical exposure times range from 6 16 hours. Developed countries have already grasped the importance of electrostatic technology in food sterilization. When the holding tank is nearly full, it is drained. This mixture is less expensive than ETO-hydrochlorofluorocarbons (HCFC), but a disadvantage is the need for pressure vessels rated for steam sterilization, because higher pressures (28-psi gauge) are required. The use of ETO evolved when few alternatives existed for sterilizing heat- and moisture-sensitive medical devices; however, favorable properties (Table 6) account for its continued widespread use.872 Two ETO gas mixtures are available to replace ETO-chlorofluorocarbon (CFC) mixtures for large capacity, tank-supplied sterilizers. The ETO-carbon dioxide (CO2) mixture consists of 8.5% ETO and 91.5% CO2. Ethylene oxide gas (EtO) is widely used to sterilize materials and products that would be damaged by methods involving heat, moisture or radiation. ETO has been linked to spontaneous abortion, genetic damage, nerve damage, peripheral paralysis, muscle weakness, and impaired thinking and memory.873 Occupational exposure in healthcare facilities has been linked to an increased risk of spontaneous abortions and various cancers.318 Injuries (e.g., tissue burns) to patients have been associated with ETO residues in implants used in surgical procedures.874 Residual ETO in capillary flow dialysis membranes has been shown to be neurotoxic in vitro.875 OSHA has established a PEL of 1 ppm airborne ETO in the workplace, expressed as a TWA for an 8-hour work shift in a 40-hour work week.