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The U.S. Environmental Protection Agency (EPA) has established tougher standards to ensure commercial sterilizers minimize ethylene oxide (EtO) emissions. A final rule released by the agency this month is intended to reduce overall EtO emissions from sterilization facilities by 90% and 21 tons per year.
High-volume commercial sterilizers have two years to comply with the new directives.
“This final rule to sharply cut toxic emissions of EtO responds to the ambition set forth by President Biden’s Cancer Moonshot,” said EPA Administrator Michael S. Regan. “We’ve arrived at a historically strong rule that will protect the most exposed communities from toxic air pollution while also ensuring that there will be a process that safeguards our nation’s critical supply of sterilized medical equipment.”
The rulemaking reflects a long-awaited response to the EtO toxicological assessment by EPA’s Integrated Risk Information System (IRIS) Program, which in 2016 indicated that the gas is a far more potent carcinogen than had been previously understood.
Medical device advocates say that the EPA used a flawed risk value for EtO that didn’t consider relevant and newer studies that demonstrated the risk to be far lower than the numbers the agency’s assessment found. Advocates say this misguided the agency’s review of sterilization facilities and emissions, as well as the final regulation.
EPA noted that there are 88 commercial sterilization facilities in the U.S. — many of which are located near residences, schools and other public entities — and determined that approximately 23 of these facilities pose high cancer risks to the surrounding communities.
“This is one of the most important measures the administration is taking to reduce EtO emissions,” said Tomas Carbonell, Deputy Assistant Administrator for Stationary Sources in the EPA’s Office of Air and Radiation. “Once the rule is in full effect, no individual will be exposed to levels corresponding to lifetime cancer risks greater than 100 in one million, which is the benchmark for elevated risk under the Clean Air Act.”
Stringent Regulations
The type of EtO that comes out of commercial sterilizers is called stack emissions, which is typically captured by control systems that break down the gas and release it at a much lower level. EtO that doesn’t get drawn into control systems escapes through leaks and gaps in the sterilization system or through a facility’s windows and doors.
“Our analysis of sterilization facilities showed that a majority of the community risk was caused by these room air emissions,” said Jonathan Witt, Environmental Engineer in the EPA’s Office of Air Quality and Standards. “The final rule addresses those types of emissions and requires facilities to put in several safeguards to control pollution.”
EPA issued a proposed rule in April 2023 and conducted extensive outreach to communities and stakeholders, with public hearings, national webinars and public meetings hosted by regional EPA offices. Based on this input, EPA strengthened the final rule’s standards to include:
- Established standards for currently unregulated emissions, such as building leaks and chamber exhaust vents, to account for technological developments in pollution control.
- Strengthened standards for sources of EtO emissions, such as sterilization chamber vents and aeration room vents.
- Continuous emissions monitoring and quarterly reporting for most commercial sterilizers to provide local communities and governments and EPA with data to ensure EtO emissions are not entering the outdoor air.
- Subjecting sterilizers to emission standards during periods of startup, shutdown and malfunction so there is continuous clean air protection.
EPA increased requirements for the continuous monitoring of commercial sterilizers and the regular reporting of emission levels to confirm air pollution control systems are working properly. The final rule requires the use of proven technology that routes EtO emissions into an air pollution control device that destroys virtually all the excess gas and the continuous monitoring of the emissions from the control equipment to ensure that it’s working properly.
Sterilization facilities must submit emissions data electronically four times a year, and EPA will make the information public.
“Collecting data regularly creates transparency and accountability,” Carbonell said. “It will provide EPA with data to ensure EtO emissions are controlled. This will also increase EPA’s ability to verify that facilities are meeting our standards — and to hold facilities accountable if they are not.”
Factoring in the Feedback
EPA received more than 46,000 comments about last year’s proposed rule and incorporated suggested changes into the final version. The time required to comply with the new standard was one of the top concerns among the submitted comments.
“In 2023, EPA proposed an 18-month compliance deadline for all existing commercial sterilizers,” Witt said. “We are now providing the maximum time allowed under the Clean Air Act — two years — to comply with the final rule for the highest-use commercial sterilizers, which use more than 60 tons of EtO per year. That time is expected to be adequate. Facilities that commence work on these emission reduction efforts immediately will be able to comply with the requirements.”
To address concerns about basing emission rates on the standard pound per hour, EPA is instead employing percentage-based emission standards in a percent reduction format. Higher-use facilities and higher-concentration streams will generally have higher emission reduction standards than lower-use facilities and lower-concentration streams.
For example, facilities that use 30 tons of EtO per year must achieve a 99.99% emission reduction, while facilities that use more than four tons but less than 20 tons per year must achieve an 80% reduction.
The final rule lays out a thoughtful process that minimizes the cost of compliance and potential impacts on the medical device supply chain, according to Carbonell.
That remains to be seen as the medical device industry responds to the new directives.
Approximately 50% of all medical devices are sterilized with EtO, including surgical kits and drills, and most surgeries involve at least one device that has been sterilized with EtO, according to AdvaMed. The industry organization has vocalized that EtO restrictions could lead to capacity reduction at sterilization facilities and the revalidation of millions of products.
FDA took steps alongside EPA’s review of the use of EtO in medical devices by updating guidance documents, recognizing new sterilization processes and launching innovation challenges. The agency also hosted a series of town halls, including one this month on Submission and Review of Sterility Information in Premarket Notification (510(k)) Submissions for Devices Labeled as Sterile.
“The finalized rule is focused on the changes required of the sterilization facilities and the capture of any emissions throughout the facility,” said Wendy Mach, Senior Director of Technical Services at Canyon Labs. “It makes me wonder how the proposed $313 million implementation costs will be passed down to orthopedic manufacturers.”
Overall, however, she believes the rule is a good compromise between ensuring public safety and maintaining public health through the proper sterilization of medical devices.
At OMTEC 2024, Mach will discuss what orthopedic companies need to know about the current sterilization landscape and alternative sterilization methods that will limit the use of EtO.
For more information about the final rule, visit EPA’s Final Amendments to Strengthen Air Toxics Standards for Ethylene Oxide Commercial Sterilizers webpage or email EPA with questions about the new requirements.
