CHICAGO (CBS) — Accusing a Willowbrook company of releasing dangerous levels of a carcinogenic gas into the air for more than a decade, Illinois Attorney General Lisa Madigan and DuPage County State’s Attorney Robert Berlin are asking a judge to impose strict new limits on the plant, or shut it down altogether.

In a lawsuit filed Tuesday in DuPage County, Madigan and Berlin are asking for court-ordered limits on emissions of ethylene oxide from the Sterigenics plant, or to shut down its operations.

“We are alleging that since at least 2006, through July of this year, the defendant, Sterigenics U.S., LLC, allowed the release of ethylene oxide gas into the atmosphere dangerously close to a densely populated residential area with nearly 20,000 people living within one mile of the alleged release. The issue of clean air is not negotiable,” Berlin said in a statement.

The Chicago Tribune reported last week that Gov. Bruce Rauner’s office and the Illinois Environmental Protection Agency knew about the cancer risks caused by the Sterigenics plant last December, but kept the information secret for eight months.

“For too long, Sterigenics emitted a dangerous, toxic chemical into the air putting the public’s health at risk,” Madigan said in a statement. “In addition to filing our lawsuit, I urge the General Assembly to pass legislation to ban or greatly restrict the use of ethylene oxide in Illinois. I appreciate State’s Attorney Berlin’s assistance in protecting the community and the environment.”

At least three other lawsuits have been filed against Sterigenics. Cancer survivor Susan Kamuda sued the company in September.

“I was diagnosed with breast cancer 10 years ago,” Kamuda stated, claiming it was a diagnosis that came out of the blue since she does not have any family with history of the disease.

In August, a U.S. Department of Health and Human Services’ Agency for Toxic Substances and Disease Registry (ATSDR) report was released, stating residents and workers in the Willowbrook area have been exposed to elevated airborne ethylene oxide concentrations from the Sterigenics facility.

Kamuda said after hearing about the report, she started to think the known carcinogen may be the cause of her cancer.

“We’re less than half a mile, about three blocks from Sterigenics,” Kamuda said. “We’ve lived in our house since 1985.”

Kamuda is not alone. At least two other law firms have filed lawsuits against Sterigenics on behalf of clients.

“This has been going on for 34 years and we just found out about this in the last month,” stated Jeff Kroll, Kamuda’s Attorney. “There’s outrage in the community. This is now the 19th largest cancer cluster in the country. This is in the top one percentage for incidents of cancer and it is no coincidence.”

Kroll hopes the lawsuit will help Kamuda and her husband get answers as to who knew about possible issues at Sterigenics.

“The reason I’m filing this lawsuit is because I want to stop them. I want to stop them from poisoning our neighborhood,” Kamuda said.

Sterigenics has said its facility operates within state and federal limits.

“Unfortunately, the community has been exposed to a lot of inaccurate and misinterpreted information and we are committed to getting the real facts to residents who, based on what they have been hearing and reading, are understandably concerned,” a Sterigenics spokesperson said in response to Kamuda’s lawsuit.

Rauner has former business ties to the company and in August was adamant in saying the emissions are not a public health hazard. However, he has since urged Madigan’s office to seek a court order to shut down the plant until it can be proven emissions are safe.