Propylene glycol isn't really used in anti-freeze, the good doctor is confused (which probably comes from practicing medicine well past the age where in other more reputable professions, such as oh, janitorial duties, one would be forced to retire) the stuff in anti-freeze is Ethylene glycol. Propylene glycol can be used in some systems where ethylene glycol can't be used such as where it would come in contact with food or even IN food. The FDA recognizes propylene glycol as generally safe. In the future, I wish these news agencies would conduct interviews with people who have done at least as much research as it takes to hit Wikipedia.