DuPage County residents suing a medical sterilization company for releasing cancer-causing emissions, claim the company has intentionally channeled more than $1 billion to its shareholders in an effort to reduce any possible payout related to the litigation.Sterigenics, which closed its DuPage County facilities last year, and its parent company Sotera Health LLC are facing at least 75 personal-injury cases stemming from the facilities’ emissions of ethylene oxide, a colorless gas used for sterilization primarily of …