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Disposing Unused Antifreeze?

We had a jug of antifreeze- about half full- form a small hole and leak out.
<br/> How can we dispose of this stuff? Used antifreeze is considered hazardous waste but I guess unused is not?
<br/> Thanks


  • edited June 2007
    Antifreeze in any form is considered a hazardous material and is very poisonous. Dogs and other animals will lap the stuff up like mana, because of its sweet odor.

    I'm lucky enough to be a few minutes from a facility that accepts used oil, antifreeze, oil filters, AND oil containers. If there isn't such a place near you (perhaps by the local landfill?), most auto parts stores or shops will accept it for disposal.
  • edited June 2007
    We've had this question often before. I run into trouble each time I respond but I'm sticking to my guns.

    There is NO federal EPA regulation regarding the disposal of antifreeze. A few states may have such regulations but these are intended primarily for those shops that collect large quantities of it.

    Since small quantities of antifreeze possess no environmental hazard and it is biodegradable, you may dispose of it safely by sprinkling it on your lawn or gravel driveway. You may do so with a clear conscience.
  • edited June 2007
    It's ethylene glycol. It's a hazard to animals. Don't dispose of it in the environment, no storm drains. You can, however, dispose of it the city sewer system. All waste water is processed, so dump it down a toilet or a sink. That's the next best way if you can't find a proper disposal facility.
  • edited June 2007
    Well, you'd have a clear conscience until your pets and neighborhood animals die from ingesting the coolant. Call your local garage or repair facility and ask them what to do with it. It is hazardous waste, any advice to dump it on the lawn is bad advice.

    And while dumping coolant might not be illegal in all states, cruelty to animals is, and that's what you'd be charged with if you dump it on your lawn and animals die.
  • edited June 2007
    There is NO federal EPA regulation regarding the disposal of antifreeze. A few states may have such regulations but these are intended primarily for those shops that collect large quantities of it.

    I believe that is true, but the feds do have rules by which the states can and many if not all do regulate it.

    It is also true that at least some states have regulations intended for large shops, but they also may well apply to individuals.

    Since the substance is harmful to animals and humans, it would be a very poor idea not to find a safe disposal method in your area.

    I suggest asking at the location supplying your antifreeze and local authorities until you get a suitable answer.
  • edited June 2007

    Antifreeze should only be disposed of by taking it to an autoparts shop or to a facility that specializes in disposal of hazardous waste. In my county, there are several sites designated for collection of motor oil, antifreeze, paint, insecticide, and other hazardous liquid materials several times a year, and it is amazing to see the lineup of cars each time that these collections are performed.

    I believe that you will find that it is illegal in most areas to dispose of antifreeze in the sanitary sewer system, due to the nature of this substance.

    Is wastewater treated? Yes, it is treated in order to reduce the hazards of the infectious agents that are in it. Waste water is not treated with the intention of neutralizing industrial chemicals, and in fact, disposal of industrial chemicals will frequently cause harm to the equipment that is used to treat waste water.

    It is very naive (and dangerous) to assume that waste water treatment plants are set up to neutralize any substance that someone chooses to dump into a toilet.
  • edited June 2007
    It's ethylene glycol. It's a hazard to animals.
    Propylene glycol antifreeze is biodegradable and is much less toxic to pets, children, and wildlife.

    AMSOIL (

    SIERRA (, made by PEAK.
  • edited June 2007
    Some communities have recycling programs for antifreeze. If you live where there is such a program, then recycle it. It'll be rerefined eventually.

    Many communities don't recycle Ethylene Glycol and permit small quantities to be disposed of in the sewer system. That's perfectly OK and responsible also. Pouring the stuff on the ground would be my last choice, but in some rural areas, it may be the only option. Unlike motor oil, antifreeze poured on the ground will not still be there years from now.

    The stuff is toxic, mildly irritating, and -- when not diluted with water -- it'll burn (albeit poorly). In mammals, Ethylene Glycol decomposes to Oxalic acid for which the body has very limited tolerance. (But it does have some tolerance -- which is a good thing since many leafy vegetables contain some Oxalic acid).

    Ethylene Glycol and its less common and less toxic cousin Propylene Glycol are biodegradable. They are not going to stay in the environment very long. The material data sheet says 1-10 days. You are surely not going to pollute aquifers with a gallon or two of antifreeze. Neither are you going to damage the local waste water treatment facility with DIY amounts of antifreeze. ... Unless it is a very small facility like a septic tank.

    The major concern is to protect small animals by doing something responsible about spills. Personally, I think washing them down with copious amounts of water to reduce the concentration to non-lethal levels is probably about as good an idea as any.
  • edited June 2007
    Check with your city.

    Some allow the disposal of used anitfreeze down the drain. Mine does. The only thing they ask is that run water while pouring it down the drain to dilute it as much as possible.

    If you have a septic system, don't pour it down the drain. Ethylene glychol will kill off the micro-ogranisms that allows the septic system to work.

  • edited June 2007
    As others have stated, some governments want it poured down the drain, others do not. Check with your sewer system if you have one.

    I have my flame suit on. If someone's pet comes into my yard and dies because it drank something, tough luck. Too bad the pet did not have a more responsible owner. The only toxicity issue I might worry about is for wild life or small children.
This discussion has been closed.