SPRINGFIELD — Gov. J.B. Pritzker signed into law toughened regulations on the use of ethylene oxide gas in Illinois.Republicans and Democrats alike said during the spring legislative session that the state needed to impose more limitations on the carcinogenic gas used for sterilization and as an agricultural pesticide.Pritzker signed the measures to make Illinois the “strictest state” when it comes to laws about ethylene oxide, or EtO.The passage of the measures comes in response to ethylene oxide leaks …