In April, the U.S. Environmental Protection Agency proposed limiting EtO emissions from sterilization facilities by 80% to minimize the risk of people developing cancer from exposure to the gas. To support manufacturers transition to other, FDA is doing it’s part by suggesting alternate methods

Ethylene oxide sterilization is an important sterilization method that manufacturers widely use to keep medical devices safe. For many medical devices, sterilization with ethylene oxide may be the only method that effectively sterilizes and does not damage the device during the sterilization process. Medical devices made from certain polymers (plastic or resin), metals, or glass, or that have multiple layers of packaging or hard-to-reach places (for example, catheters) are likely to be sterilized with ethylene oxide.

There are two voluntary consensus standards for ethylene oxide sterilization:

• ANSI AAMI ISO 11135:2014 and
• ANSI AAMI ISO 10993-7:2008(R)2012)

These standards help ensure levels of ethylene oxide on medical devices are within safe limits since long-term and occupational exposure to ethylene oxide has been linked to cancer.

The U.S. Environmental Protection Agency proposed limiting EtO emissions from sterilization facilities by 80% to minimize the risk of people developing cancer from exposure to the gas.

The FDA announced two public innovation challenges to encourage the development of new approaches to medical device sterilization:

Challenge 1: Identifying Sterilization Alternatives:

The goal of this challenge is to identify safe and effective sterilization methods or technologies for medical devices that do not rely on ethylene oxide and that meet these criteria:

• Compatibility: The method or technology should be compatible with a large cross -section of materials used to manufacture or fabricate medical devices as well as packaging materials or sterile barriers. The materials, devices and barriers of particular interest are those that are compatible with ethylene oxide sterilization.

• Scalability and High Throughput: The method or technology should have the potential to be scalable and allow for the effective sterilization of large volumes of devices.

The challenge submissions were expected to succinctly describe:

• Anticipated benefit of the technology or method
• Impact of the method or technology on public health as compared to other available alternatives
• Compatibility of the method or technology with medical device materials
• Capability of the method or technology to ensure scalability and high throughput for safe and effective sterilization of large volumes of devices

The FDA also considered factors such as:

• Feasibility of the strategy or technology
• Impact of the FDA’s involvement

Elements that would have been considered within this challenge scope:

• Methods that can sterilize a wide range of polymeric materials without changing the chemical and physical properties of the polymers by degrading them (e.g., through oxidization, chain scission, or other unfavorable reactions) or by generating unacceptable levels of toxic by-products such as leachables.
• Materials or medical devices that are typically sterilized by ethylene oxide.
• Methods that can or have potential to sterilize bulk volumes/large loads of products
• Methods that employ the use of technologies and infrastructure that is readily accessible or rapidly developed to medical device manufacturers and sterilization providers in the United States.

The FDA updated the Recognized Consensus Standards database to include the complete recognition of one sterilization standard and two Technical Information Reports (TIRs) intended to advance innovation in medical device sterilization processes, support manufacturers’ use of “low temperature vaporized hydrogen peroxide”, and streamline the premarket review process:

• ISO 22441:2022 Sterilization of health care products Low temperature vaporized hydrogen peroxideRequirements for the development, validation and routine control of a sterilization process for medical devices
• AAMI TIR104:2022 Guidance on transferring health care products between radiation sterilization sources
• AAMI TIR17:2017/(R)2020 Compatibility of materials subjected to sterilization

Low Temperature Vaporized Hydrogen Peroxide: This method uses hydrogen peroxide vapour under vacuum to sterilize medical devices. VHP technology demonstrates low toxicity and rapidly decomposes into non-toxic by-products of water vapour and oxygen. Once the vapour has been removed from the sterilization chamber by a series of vacuum/air pulses, unlike other processes such as ethylene oxide, no further aeration is required.

Challenge 2: Reduce the EtO Emission:

The goal of this challenge is to develop strategies or technologies to reduce emissions to as close to zero as possible from the ethylene oxide sterilization process.

The strategies or technologies may allow for the:

• Use of lower levels of ethylene oxide while maintaining assurance that devices are safely and effectively sterilized.
• Capture of ethylene oxide emissions and/or transformation to harmless by products.
• Detection, measurement, tracking, and containment of fugitive emissions to prevent or minimize emissions into the sterilization facility or environment.
• Safe use of ethylene oxide while minimizing harmful exposure (such as toxicity and carcinogenicity) to sterilization workers and nearby communities.

The challenge submissions were expected to succinctly describe:

• Anticipated benefit of the strategy or technology
• Impact of the strategy or technology on public health as compared to other available alternatives
• Compatibility of the strategy or technology with medical device materials
• Capability of the strategy or technology to ensure scalability and high throughput for safe and effective sterilization of large volumes of devices

The FDA also considered factors such as:

• Feasibility of the strategy or technology
• Impact of the FDA’s involvement

Elements that would have been considered within this challenge scope:

• Methods that can or have potential to sterilize bulk volumes/large loads of products
• Methods that employ the use of technologies and infrastructure that is readily accessible or rapidly developed to medical device manufacturers and sterilization providers in the United States
• Strategies to control or reduce bioburden prior to sterilization
• Incorporation of processes that use lower levels of ethylene oxide while assuring that requisite sterility assurance/sterilization is attained
• Capture of ethylene oxide emissions and transformation to harmless byproducts
• Detection, measurement, tracking, and containment of ethylene oxide emissions or byproducts to minimize or prevent dissemination into the sterilization facility and environment
• Allowing for the safe use of ethylene oxide while minimizing exposure to sterilization workers or nearby communities