The emission of ethylene oxide (EtO) from sterilization facilities into surrounding communities has raised cancer concerns, warnings, and closures that threaten the critical flow of sterile supplies in healthcare, the FDA reports.

Infection preventionists should keep communication channels open with central sterile supply and other key colleagues to ensure spot shortages of equipment do not pose a threat to patient safety.

“Regarding a potential for a shortage of any one type of medical device, we are frequently communicating with manufacturers, healthcare organizations, group purchasers, and trade organizations so we can keep our finger on the pulse of what is happening,” said Suzanne B. Schwartz, MD, MBA, associate director for science and strategic partnerships at the FDA Center for Devices and Radiological Health.

Thus far, shortages of sterile equipment have been largely headed off, but a system already operating at capacity could be vulnerable to a cascade effect if stakeholders are not prepared for plant closures, she said at a CDC meeting.

“The nation is not seeing the spot shortages that we might otherwise be seeing,” Schwartz said. “I want to underscore that once you start to have more of a domino effect, that is going to be significantly felt.”

Classified as a carcinogen in certain doses, EtO is used to sterilize about half of new medical devices and equipment before they are packaged and shipped to hospitals. This includes terminally sterilized new products like surgical kits, sterile packs, stints, sutures, clamps, and tracheostomy tubes. Any disruption in the flow of these essential supplies must be balanced against the potential for raising the risk of cancer in the community, Schwartz told the CDC’s Healthcare Infection Control Practices Advisory Committee (HICPAC).

“I want to emphasize that FDA recognizes and is very sensitive to the environmental concern for ethylene oxide emissions that are released into the air at unacceptable levels — levels that can present an increased risk to public health in surrounding communities” she said.

EtO is used widely in sterilization facilities because it is compatible with many of the materials used in construction of the equipment. Sterilization facilities may have limited options to go to other modalities that may damage or otherwise compromise safe use of the equipment on patients.

The FDA is looking for alternatives to EtO and different ways to use the sterilant; for example, reducing the quantity of EtO used in sterilization, which may reduce environmental exposures while preserving the safe use of the devices, she said.

Facility Shutdown

A critical moment in this unfolding situation occurred on Feb. 15, 2019, when the Illinois Environmental Protection Agency (EPA) issued a “seal order”1 to stop Sterigenics in Willowbrook, IL, from further sterilizing medical products with EtO, Schwartz said.

In making the move, the EPA cited ambient air sampling and a report by the CDC’s Agency for Toxic Substances and Disease Registry (ATSDR) that concluded, “If measured and modeled data represent typical ethylene oxide ambient concentrations in ambient air, an elevated cancer risk exists for residents and offsite workers in the Willowbrook community surrounding the Sterigenics facility. These elevated cancer risks present a public health hazard to these populations.”2

The Illinois Department of Public Health conducted a separate epidemiologic study of cancer incidence near the facility over a 20-year period. Researchers found that cancer risk was elevated in general, but cited confounding variables that undermined a definitive conclusion. For example, interstate traffic adds to EtO emissions in the same area.

“The study’s results, when taken as a whole, indicated that some cancers were elevated in populations living near the Sterigenics facility in Willowbrook,” the state researchers concluded.3 “Many apparent differences and inconsistences, however, existed between genders, across study areas, and among cancer sites.”

On June 24, 2019, Sterigenics applied for renovations that would reduce emissions and comply with an Illinois state law passed in the wake of the closure. According to a statement by Sterigenics, “The application seeks permits to install new equipment which would establish a permanent total enclosure through the use of negative pressure, increase the number of emission control stages, and combine existing emissions stacks into one common stack at the facility. Sterigenics remains in compliance with legal obligations and is taking all appropriate legal actions to resume operations at Willowbrook.”4 Sterigenics has nine sites and approximately 150 contract sterilizers in the United States, Schwartz said.

Viant, a sterilization plant in Grand Rapids, MI, also announced it is shutting down at the end of 2019. In a letter5 to local residents, Viant said a self-reported EtO leak by the plant in 2017 was cited as a violation by the Michigan Department of Environmental Quality. Viant said in the letter it was shutting down sterilization activities because it is not part of their core business.

The closures are a concerning trend, given that existing sterilization capacity is hard-pressed to meet demand.

“Contract sterilizers are working at close to maximum capacity in terms of devices coming in and going out,” Schwartz said. “They are working 24/7. The impact of a closure of a single site can have significant consequences on the availability of medical devices that need to be delivered to supply chains, hospitals, and healthcare organizations.”

The situation is in flux as both the EPA and the CDC are conducting surveillance of EtO emissions and health affects at other sterilization plants and the surrounding communities nationally. Congress is asking the FDA for updates on the situation, Schwartz said.

The FDA plans to form an advisory committee on the issues of EtO sterilization and sterile device supply in the fall, she said. The agency also is going to issue an “innovation challenge” in the coming months to solicit solutions that could help reduce EtO emissions and explore alternative sterilization technology.


  1. Illinois EPA. Order to prevent any new sterilization cycles using ethylene oxide. Feb. 15, 2019. Available at:
  2. Agency for Toxic Substances and Disease Registry. Letter Health Consultation: “Evaluation of potential health impacts from ethylene oxide emissions,” Sterigenics International, Inc., Willowbrook, IL. Aug. 21, 2018. Available at:
  3. Illinois Department of Public Health. Cancer incidence assessment near Sterigenics in Willowbrook, IL, 1995-2015. March 29, 2019. Available at:
  4. Sterigenics. Sterigenics announces plans to enhance emissions controls at Willowbrook facility. June 27, 2019. Available at:
  5. Viant. Letter to residents. March 4, 2019. Available at: