Illinois EPA Director Seals Portions of Sterigenics Due to Public Health Hazards from Ethylene Oxide Emissions

SPRINGFIELD - Illinois Environmental Protection Agency Acting Director John J. Kim has issued a Seal Order to the Sterigenics U.S., LLC, facility located at 7775 South Quincy Street, in Willowbrook, DuPage County, to prevent the commencement of any new sterilization cycles using ethylene oxide to prevent emissions which present an imminent and substantial endangerment to residents and off-site workers in the Willowbrook community.

The Seal Order restricts access to the ethylene oxide storage vessels so as to preclude introduction of ethylene oxide into a sterilization chamber. Only persons authorized, in writing, by the Director of the Illinois EPA may access the sealed vessels to conduct activities within the scope of their specified authorization.

Following ambient air sampling by U.S. EPA in the spring of 2018, one of the conclusions of the Agency for Toxic Substances and Disease Registry (ATSDR) noted "if measured and modeled data represent typical ethylene oxide ambient concentrations in ambient air, an elevated cancer risk exists for residents and off-site workers in the Willowbrook community surrounding the Sterigenics facility. These elevated cancer risks present a public health hazard to these populations."

The ATSDR used the highest residential area and commercial air sampling results (2.1 micrograms per meter3 and 9.1 micrograms per meter3, respectively) to reach its conclusion. Since that time, ambient air sampling conducted by U.S. EPA and the Village of Willowbrook has consistently found outdoor ambient levels of ethylene oxide in commercial and residential areas as high or higher than the levels used by the ATSDR.

The Illinois EPA and Illinois Attorney General's Office have been in numerous discussions with Sterigenics to discuss how to further reduce ethylene oxide emissions. Recent elevated sampling results, along with Sterigenics' refusal to voluntarily suspend operations, have resulted in the issuance of the Seal Order.

The Seal Order will remain in effect until it is rescinded by Acting Director Kim.