A Regulatory Rollback With Real Health Stakes
The US Environmental Protection Agency is moving to loosen limits on emissions of ethylene oxide, a colorless gas widely used to sterilize medical devices that cannot withstand heat or radiation sterilization. The proposal is generating significant concern among public health advocates because ethylene oxide is classified as a known human carcinogen, linked to elevated rates of lymphoma and breast cancer in workers and communities near sterilization facilities.
Ethylene oxide is used to sterilize approximately 20 million medical devices annually in the United States — including catheters, heart valves, surgical gloves, and numerous implantable devices. There is currently no widely available alternative sterilization method for many of these products, making the gas an embedded part of the medical device supply chain.
Why Sterilization Facilities Use Ethylene Oxide
Ethylene oxide's properties make it effective for a wide range of sensitive medical products. The gas penetrates packaging and device materials at low temperatures, killing bacteria, viruses, and fungi without damaging delicate components. Heat sterilization can warp plastics or degrade electronic components. Radiation sterilization works for many products but can degrade certain polymers and cannot be used for biological materials or some active implantable devices.
Approximately 50 percent of all sterile medical devices used in the US are processed with ethylene oxide, according to the FDA. The gas is used at roughly 86 commercial sterilization facilities and an additional 1,500 hospital-based sterilizers. Commercial facilities process single-use devices in larger quantities, while hospital systems use ethylene oxide for heat-sensitive reusable instruments.
The Health Risks and Prior Regulatory History
The EPA classified ethylene oxide as a known human carcinogen in 2016, revising an earlier assessment that had categorized it as a probable carcinogen. The reclassification was based on epidemiological evidence from workers at EtO facilities showing elevated rates of lymphoma and breast cancer, as well as animal studies demonstrating carcinogenicity across multiple species.
In 2019, the EPA released an updated risk assessment that substantially raised estimated cancer risks from EtO exposure — in some cases by orders of magnitude. That assessment prompted community organizing and legal challenges near facilities in Illinois, Georgia, Michigan, and other states. The Biden administration moved to tighten EtO emission standards in 2024, imposing substantial compliance costs on the industry and prompting concerns about potential sterilization capacity constraints.
The Proposed Rollback and Its Justification
The current EPA proposal would move in the opposite direction, potentially loosening limits established by the prior administration. The stated rationale involves balancing cancer risk against risks to the medical supply chain if sterilization capacity becomes constrained — a legitimate consideration that nonetheless creates tension with the EPA's core mission to protect human health.
Proponents of looser standards argue that driving commercial sterilizers out of business or forcing dramatic throughput reductions could delay access to sterile medical devices, with its own health consequences. Several medical device manufacturers and hospital groups have submitted comments to this effect in prior rulemaking proceedings.
Community and Scientific Response
Health advocates in communities near EtO facilities argue that residents — who have no choice about their proximity and derive no direct benefit from the economic activity — bear a disproportionate cancer burden. Epidemiological studies near several facilities have documented elevated cancer rates consistent with EtO exposure, and community groups have organized extensively to push for stricter controls.
Cancer researchers have expressed concern that loosening EtO limits amounts to accepting higher rates of preventable cancer in exchange for regulatory convenience. Unlike many air pollutants where dose-response relationships are uncertain, EtO's carcinogenicity is considered well-established and scientifically uncontroversial.
The sterilization industry has been investing in alternative methods to reduce EtO dependence, including gamma radiation, electron beam, X-ray sterilization, hydrogen peroxide vapor, and peracetic acid systems. But these alternatives cannot yet fully replace EtO for all device categories, and the timeline for industry-wide transition remains years away. The outcome of the EPA's current proposal will significantly influence the pace of that transition.
This article is based on reporting by Medical Xpress. Read the original article.
