The Environmental Protection Agency on Friday proposed to weaken limits on emissions of ethylene oxide, a cancer-causing gas, from manufacturing facilities that use it to sterilize medical devices.
The move revived a long-running debate about the paradoxical effects of ethylene oxide on public health. While it plays a crucial role in sterilizing lifesaving medical devices like pacemakers and syringes, long-term exposure can cause leukemia and other types of cancer among people who work in or live near medical sterilization facilities.
“The Trump E.P.A. is committed to ensuring lifesaving medical devices remain available for the critical care of America’s children, elderly and all patients without unnecessary exposure to communities,” Lee Zeldin, the E.P.A. administrator, said in a statement.
The agency’s proposed rule would loosen limits on ethylene oxide emissions from around 90 commercial sterilization facilities across the country. Roughly 2.3 million people live within two miles of these facilities in what are often low-income neighborhoods or communities of color, according to an analysis by the Union of Concerned Scientists, an environmental group.
The proposal is the E.P.A.’s latest move to relax pollution limits in an effort to lower costs for industries. In recent months, the agency has also weakened restrictions on mercury from coal-burning power plants and repealed a scientific finding that allowed the government to regulate planet-warming pollution from cars and trucks.
In a news release, the E.P.A. said the Biden administration’s stricter limits on ethylene oxide emissions would be difficult, if not impossible, for many facilities to meet. In particular, the agency said it was proposing to rescind a requirement that facilities conduct round-the-clock monitoring of their ethylene oxide emissions.
Ethylene oxide is used to sterilize about half of all medical devices in the United States, helping to prevent infections in patients undergoing surgeries and other treatments. It is applied to roughly 20 billion medical devices each year, including catheters, heart valves, stents and ventilators.
The gas is valued for its ability to destroy bacteria, viruses and other microorganisms without damaging delicate materials like plastics. There is no viable alternative on the market, the E.P.A. said in the news release.
At the same time, inhaling the gas can cause coughing, dizziness, fatigue and nausea. Long-term exposure can damage the brain and central nervous system and can increase the risk of breast cancer, leukemia, lymphoma and other cancers of the white blood cells.
The E.P.A. first classified ethylene oxide as a human carcinogen in 2016. The agency based the determination on studies showing that the gas was 60 times more toxic to children and 30 times more toxic to adults than previously thought.
The Biden administration significantly strengthened limits on ethylene oxide emissions in 2024. The move was part of President Joseph R. Biden Jr.’s “moonshot” effort to sharply cut cancer deaths in the United States.
At the time, Biden administration officials estimated that the rules would reduce ethylene oxide emissions from sterilization plants by 90 percent. Some of the plants would have been required to install or upgrade pollution controls.
President Trump has already exempted 40 sterilization plants from complying with the Biden-era limits on ethylene oxide for two years. In a proclamation in July 2025, Mr. Trump argued that the rules would “likely force existing sterilization facilities to close down, seriously disrupting the supply of medical equipment.”
The Natural Resources Defense Council, the Southern Environmental Law Center and other environmental groups have filed a lawsuit to block the exemptions. The suit, which is pending in federal court in Washington, argues that many of the sterilization facilities were capable of complying with the Biden-era rules using existing pollution controls.
“This administration is systematically looking for ways to let polluters off the hook,” Sarah Buckley, a senior attorney at the Natural Resources Defense Council, said in a statement. “If this abuse of authority is left unchecked, communities will pay the price in higher cancer risks.”
AdvaMed, a group that lobbies for the interests of medical device manufacturers, said in a statement that the proposed rule issued on Friday would ensure the supply of safe, sterile devices without interruption.
The E.P.A. will solicit public comments on the proposed rule for 45 days after its publication in the Federal Register. The agency will then finalize the rule, likely within the next year.
