Ethylene Oxide

Parents Giving Children Piggyback Ride On Walk By Lake
What is EtO?

Ethylene oxide (EtO) is a gas. EtO can harm your health if you’re exposed to high enough levels of it over long periods of time.

EtO is used to

  • make everyday items like household cleaners, antifreeze, polyester, and cosmetics,
  • sterilize medical equipment, and
  • control insects and mold in some agricultural products, including spices and herbs.

EtO is also found in tobacco smoke. In addition, very small amounts of EtO exist in nature, including in the human body.

Low levels of ethylene oxide have been measured in the air in many areas of the United States without any known source; everyone is exposed to some EtO.

What is ATSDR doing to address EtO in communities?
A group of people at a community meeting.

In 2016, the U.S. Environmental Protection Agency (EPA) released a report showing that ethylene oxide (EtO) is more likely to cause cancer than researchers had thought. Since then, ATSDR has been working with government partners and communities to help protect people from EtO. This includes the following:

Helping our partners talk to people about EtO

ATSDR is working with state and federal partners to help people understand what we know about EtO — and what we’re still working to learn. We’re also providing guidance to help local governments, businesses, school boards, and other organizations address health concerns about EtO in their communities.

Educating healthcare providers

ATSDR has published a clinician brief on ethylene oxide to help health care providers learn about the health effects of EtO and how to diagnose and treat patients who were exposed. ATSDR also supported the University of Illinois at Chicago (UIC) in hosting a webinar about cancer risk to people who live near facilities that release EtO into the air.

Conducting public health consultations
Health consultation in Lake County, Illinois

In March 2019, the Lake County Health Department and Community Health Center asked ATSDR to assess if EtO in the air would pose a public health hazard to the Lake County community.  Specifically, they asked ATSDR to review whether EtO levels in outdoor air around Medline Industries (Medline), a medical sterilization facility in Waukegan, Illinois, and Vantage Specialty Chemicals (Vantage), a chemical manufacturing plant in Gurnee, Illinois, pose a public health hazard to the Lake County community. Both facilities are in Lake County, about 3 miles from one another.

In 2024, ATSDR issued a draft health consultation for public comment based on EtO air sampling

    • — near Vantage from June 2019 to May 2020,
    • — near Medline from June 2019 to September 2023, and
    • — at background locations.

https://wwwn.cdc.gov/TSP/PHA/PHAListing.aspx?StateIndicator=IL

The draft version will be available for public comment from June 21, 2024, through August 5, 2024. Submit comments to ATSDR’s record center through email at ATSDRRecordsCenter@cdc.gov or in writing. Address written comments to Agency for Toxic Substances and Disease Registry, Attn: Records Center, 4770 Buford Highway NE, MS S106-5 Atlanta, Georgia 30341. ATSDR will respond to comments and issue a final consultation.

Lake County—Questions and Answers

Health consultations in Willowbrook, Illinois

In 2018, EPA Region 5 requested that ATSDR review their air modeling of EtO emissions from the Sterigenics commercial sterilization facility in Willowbrook, Illinois. EPA also asked ATSDR to review limited EtO air monitoring data EPA collected near Sterigenics May 16–18, 2018. ATSDR issued a letter health consultation in June 2018:

EPA conducted additional EtO air monitoring in Willowbrook near Sterigenics from November 2018 through March 2019. ATSDR issued a draft health consultation for public comment in November 2023, evaluating the additional air monitoring data:

ATSDR will respond to comments and issue a final consultation.

Health consultation in Cobb County, Georgia

ATSDR received four petitions in the summer of 2019 to evaluate health risks from EtO emissions from the Sterigenics commercial sterilization facility in Cobb County, Georgia. ATSDR is conducting a health consultation based on Georgia Environmental Protection Division’s (EPD’s) EtO air sampling conducted near Sterigenics and at background locations from September 2019 – April 2021.

Health consultation in Covington, Georgia

Georgia EPD requested that ATSDR evaluate EtO in outdoor air near the Becton Dickinson (BD) commercial sterilization facility in Covington, Georgia. ATSDR is conducting a health consultation based on Georgia EPD’s air sampling conducted near BD and at background locations from September 2019 – April 2021, as well as air sampling conducted by BD near the Global Distribution Center warehouse in Covington from January 2020 – August 2022.

What you need to know about EtO exposure

Most EtO in the environment is released through the air. People generally cannot smell EtO in the air unless the amount of EtO in the air is very high. Then, it may have a sweet smell.

You may be exposed to higher levels of EtO, however, if you do the following:

  • Work with EtO — for example, if you sterilize medical equipment.
  • Smoke tobacco or are around people who smoke.
  • Live near a factory that releases EtO into the air.

Researchers are working to learn more about the health effects of EtO released into the air. Specifically, they are trying to find out how EtO might affect people who live near factories that use or produce EtO.

If you are concerned about your health and EtO exposure, talk to your doctor.

How EtO Can Affect Your Health

Several factors affect whether exposure to EtO may harm your health. These include how you are exposed; how much EtO you are exposed to and how long and how often you breathe EtO; and your general health condition, genetics, age, family history, and lifestyle choices.

Occupational studies indicate that people who breathe elevated levels of EtO for years or decades are at increased risk of specific types of cancers, including non-Hodgkin lymphoma, myeloma, and lymphocytic leukemia. Studies also show that breathing elevated EtO levels for many years increases the risk of breast cancer in females. Similar cancers were also found in animal studies.

Breathing EtO may cause other adverse health effects besides cancer. However, these other health effects are a concern at levels that are thousands of times higher than what has been measured in the communities where ATSDR has conducted health assessments.

EtO Resources
General information about EtO

Check out these resources to learn more about EtO:

Information for Healthcare Professionals

Learn more about how EtO might affect your patients:

If you have questions about what ATSDR is doing to protect people from the health effects of EtO, contact us at EtO@cdc.gov.

If you’re concerned about EtO exposure at work, contact the U.S. Department of Labor’s Occupational Safety and Health Administration (OSHA).