Choosing eco-friendly products for our cars is something we can do to help protect children and animals from poisoning. More environmentally friendly antifreeze is one option. Traditional antifreeze is made with ethylene glycol, a substance that is highly toxic even in small doses. It also, unfortunately, has a sweet taste that animals find attractive. A better solution is to use propylene glycol antifreeze which, while not completely harmless, is less toxic than traditional antifreeze.
The Purpose of Antifreeze
Your car’s engine produces a lot of heat. Without a way to disperse it, the heat would be enough to destroy the engine. Having liquid circulate throughout and around the engine helps keep it cool.
It is not recommended that you put plain water in your radiator. Antifreeze has both a higher boiling point and a colder freezing point than pure water. In cold temperatures, water can freeze in your radiator or the car’s hoses, causing them to rupture. Water also can cause rust, shortening the life of the parts in your car.
Dangers of Antifreeze
Ethylene glycol antifreeze is extremely poisonous. Consumption of as little as two tablespoons can be fatal for a small child. The flavor is sweet, which makes it attractive to both children and some animals. Only a handful of states require that bittering agents be added to antifreeze to reduce antifreeze poisonings.
Symptoms of ethylene glycol poisoning include rapid heatbeat, bloody urine and blurred vision or blindness, and poisoning can be fatal within 24 hours.
Propylene glycol is similar enough to ethylene glycol in that it provides nearly the same protections in a car’s engine as traditional antifreeze. However, it is far less toxic and is even used, in small quantities, in some food products and health and beauty aids.
Making the Switch
Propylene glycol antifreeze is sold by many auto part stores. It is usually labeled as "pet safe." The antifreeze itself is red-orange in color, while traditional ethylene glycol antifreeze is tinted green.
It is extremely important to ensure that all of the old antifreeze is drained from your radiator. While it will probably not harm your car for the two solutions to mix, the high toxicity of EG antifreeze would render the safer antifreeze useless.
Old antifreeze should always be brought to a recycling center for proper disposal. Both ethylene glycol and propylene glycol are toxic to fish. And, even though both substances biodegrade to carbon dioxide and water within about a month, antifreeze can pick up heavy metals while it is being used in your car. If you must store antifreeze, make sure that it is kept in tightly sealed containers to keep it away from animals and children.
All ethylene glycol and propylene glycol are made using natural gas, which, as a fossil fuel, is not a renewable resource.
While it does not appear to be available on the consumer market, there are processors which produce recycled antifreeze. According to the EPA, recycled antifreeze reduces the need for new resources used in production. At this time, it is sold exclusively in industrial quantities to companies with large automotive fleets.
There has also been discussion of making propylene glycol from renewable resources. The product would be made from byproducts of biodiesel production, making it a much more environmentally friendly antifreeze. There is no news yet of when this product will be available at the consumer level, but, some companies are reportedly selling it for industrial applications.
EET Corporation <www.eetcorp.com/antifreeze/antifreeze-faq.htm>
Green Technology <https://www.greentechnolog.com/2008/11/glycerol_bassed_eco_friendly_antifreeze.html>
Agency for Toxic Substances and Disease Registry <https://www.atsdr.cdc.gov/toxfaqs/tf.asp?id=85&tid=21>