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EPA in Illinois

Questions and Answers: Other Topics

Other Topics

What is the level of ETO below which property values will recover?

EPA has not correlated EtO levels and property values.

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What is a safe distance to live away from a plant that uses ethylene oxide?

We know that ethylene oxide can last in the air for up to several months and be transported with prevailing winds.  At higher temperatures, especially above 50 degrees Fahrenheit, and stronger winds, we would expect ethylene oxide to transport further away from the emission source more effectively.   Our current modeling plan is designed to gain a better understanding of how much ethylene oxide is in the neighboring communities.  The current monitoring and upcoming risk assessment will tell us what ethylene oxide concentrations are in the community.

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What happens if individuals develop cancer/diseases/illnesses in the future due to being exposed to the EO?  What recourse will we have?

EPA cannot advise individuals regarding specific legal action or recourse.

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Where is the TRI reporting for 2017?

The complete 2017 TRI data set is available via EPA’s website:  A facility will trigger TRI-reporting requirements if it: (1) is in a TRI-covered industry sector; (2) has 10 or more full-time employees; and (3) manufactures, processes, or otherwise uses more than the listed threshold amount of a TRI-listed chemical during a reporting year. A facility might not report for a given year because it determined that it did not meet one or more of the above-listed requirements. In prior years, facilities owned by Sterigenics, including its Willowbrook facility, categorized themselves within a sector that would not trigger TRI reporting requirements, but nonetheless submitted TRI data.  However, none of the Sterigenics facilities submitted TRI data for 2017. Each year, EPA reviews changes in reporting, and EPA is reviewing this change in reporting.

In response to the Sterigenics facility in Willowbrok: For the past several years, Sterigenics facilities—including the Willowbrook, IL location—have categorized themselves within a sector that does not trigger TRI reporting requirements.  Although the Sterigenics facilities nonetheless submitted TRI data prior to 2017, none of the Sterigenics facilities submitted TRI data for 2017. EPA is reviewing this change in reporting.  Explore the TRI National Analysis for 2017.

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Have we checked the Sterigenics Facility in Oakbrook, IL?

Oakbrook is the Sterigenics corporate headquarters and does not use ethylene oxide.

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Are ethylene oxide emissions also a problem in Schaumburg? Sterigenics has a facility there.

That facility is closed.  View the current plant information at:

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Why is this just coming out now, when Sterigenics has been in operation since 1984?

At the time this facility began operation in 1984, and at the time the EPA rule for this source category was adopted in 1994 (and subsequently reviewed in 2006), our understanding of the risk of ethylene oxide was not what it is today. We have now begun the work to re-review that rule, but the regulation development will take time.

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My iPad is relatively old. So, I seem to be unable to see ethylene oxide impacted areas in Illinois. Suggestions? Alternative links?

It is possible that the 2014 NATA mapping application will not work properly with some older devices or older web browsers. We have tested the app with current web browsers (Google Chrome, Internet Explorer, Firefox) and it seems to work properly with them. The app is easiest to use on a computer with one of these browsers. It also works on current portable devices, but is not as user friendly.

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