The main ingredient in antifreeze -- ethylene glycol -- has a very sweet flavor and a strong candylike aroma. For wild animals and pets, it can be tempting to lick the highly poisonous antifreeze where there are spills on the ground, so clean up spills right away. Avoid temptation entirely by not walking pets near areas with lots of parked cars. Another thing you can do to help lessen the poison risk is to choose antifreeze that contains propylene glycol instead of ethylene glycol. It is far less toxic to animals and will also still have the high-performance benefits your car needs.