• Jan 27, 2020, 14:00 PM

Ethylene Oxide Update #31: Phase II Air Monitoring Completed

Phase II Ethylene Oxide Air Monitoring Completed

Health Department plans third and final phase of air monitoring

Lake County, Ill. — The Lake County Health Department, Village of Gurnee, and City of Waukegan have completed the second phase of their joint outdoor air monitoring for ethylene oxide (EtO) near Vantage Specialty Chemicals in Gurnee and Medline Industries in Waukegan. The monitoring began on October 26, 2019 and ended January 22, 2020. The Health Department expects to receive the final results from the second phase of monitoring mid-February and will post them to its website,, once they are received.

During the second phase of monitoring, over 350 samples were collected from 12 locations on 30 sampling days. This includes 14 sampling days during the temporary shutdown of EtO operations at Medline Industries, which began December 13, 2019.

“Medline’s temporary shutdown provided us with background data, in which no Medline EtO emissions were occurring and before their additional pollution controls were fully installed and operational,” said Mark Pfister, Health Department Executive Director.

A third and final 30-day period of monitoring will begin after Medline resumes its EtO sterilization operations. “We expect to resume monitoring in February, but the exact date depends on when the Illinois Environmental Protection Agency (IEPA) has tested and approved Medline’s new emissions controls and the facility is fully operational,” said Pfister. During the final phase, samples will be collected at the same 12 sites that were monitored during the second phase.

When completed, the monitoring program will include an estimated total of 600 samples collected on 54 sampling days over a 150-day period. In comparison, the U.S. Environmental Protection Agency’s air monitoring program in Willowbrook included samples collected on 49 separate days over a similar period.

Once the Health Department receives the results, officials will share them among partners and forward them to the U.S. Environmental Protection Agency (EPA), Agency for Toxic Substances and Disease Registry (ATSDR), Illinois Department of Public Health (IDPH), and IEPA which has regulatory authority over EtO emissions permitting in Illinois.

The ATSDR has agreed to conduct a health risk assessment for Lake County based on the results, and IDPH has agreed to complete a cancer incidence study that includes Lake County.

Anyone with questions about the EtO air monitoring should visit the Health Department’s website for more information,, or call (847) 377-8020.