Auto maintenance experts recommend that radiators should be flushed every one to two years. This presents a question of what to do with the radiator fluid. You have to be careful not only to store new antifreeze safely, but also to dispose of used antifreeze properly. Because ethylene glycol is a clear, colorless and sweet-tasting liquid, it is very attractive to pets and small children. Pets will lap up an antifreeze puddle because it tastes sweet.
Young children are also at risk.
If swallowed, ethylene glycol may cause depression, followed by respiratory and cardiac failure, renal and brain damage. It is often fatal. Antifreeze that is carelessly disposed of, such as poured into a storm drain or ditch, a river or stream, onto the ground or into the trash, presents a health threat to humans, animals and the environment. Flush antifreeze down the toilet or sink with plenty of water if your house connects to a sanitary sewer system. The sewage treatment plant will break down hazardous chemicals in antifreeze.