Chemical plants in Louisiana and Texas release far more of the cancer-causing ethylene oxide gas than the Sterigenics medical sterilizer plant in Illinois, which snagged national headlines this year and was shut down by state regulators.
The Environmental Protection Agency decided in late 2016 that the gas is much more dangerous than previously thought—an assessment that industry groups and some state regulators dispute. A separate federal report found that emissions from the Sterigenics medical sterilizer plant in Willowbrook, Ill. could be harmful to public health.
The report sparked a local and national outcry that ultimately led the Illinois Environmental ...