SPRINGFIELD — A court decision on whether a suburban medical supply sterilization company linked to increased cancer rates will be allowed to reopen will be delayed five weeks. A DuPage County judge ruled Wednesday that four area municipalities could be added as a party to a legal proceeding on the matter.

The DuPage County municipalities are Darien, Burr Ridge, Hinsdale and Willowbrook. All of them surround Sterigenics, a facility that has been prohibited from using ethylene oxide, a known cancer-causing chemical, in its sterilization processes since the Illinois Environmental Protection Agency put it under seal order in February.

Thus, the plant in suburban Willowbrook will remain closed until at least Sept. 6.

Judge Paul Fullerton gave those municipalities a month to submit a joint brief outlining their arguments against a consent order filed by Illinois Attorney General Kwame Raoul and DuPage County State’s Attorney Robert Berlin that would lift the seal order and provide an avenue for the company to conditionally resume ethylene oxide sterilization processes.

Once the municipalities file their brief, the other parties in the legal proceeding — the attorney general’s office and Sterigenics — would have one week to reply, making a hearing scheduled for Sept. 6 the next possible date a decision on the consent order could be made.

“It’s certainly encouraging that (the judge) is allowing these local municipalities to comment on (the consent order),” said state Sen. John Curran, a Downers Grove Republican. “My hope is this will lead to significant modifications or completely rescinding that proposed consent agreement.”

Raoul and Berlin did not object to the municipalities’ motion to intervene, and the officials released a statement noting they “recognize the need for the impacted communities to be heard.”