CHICAGO (CBS)–Concerned residents packed a community forum in Willowbrook Thursday night, demanding the closure of Sterigenics.

The plant is accused of polluting the air with cancer-causing gas.

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Sterigenics uses ethylene oxide to sterilize medical equipment. This month, the Environmental Protection Agency said tests may have overstated the amount of gas being emitted into the air.

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Several residents as well as Illinois Attorney General Lisa Madigan have filed lawsuits against the plant.

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Sterigenics claims the company is operating within the limits of its permits.