410 ILCS 1/5: Addition of bittering agent required.

Any engine coolant or antifreeze that is manufactured after January 1, 2011, and subsequently sold within the State, and that contains more than 10% ethylene glycol, shall include denatonium benzoate at a minimum of 30 parts per million and a maximum of 50 parts per million as a bittering agent within the product so as to render it unpalatable.