# How Much Anti-Freeze Can One Safely Consume? **URL:** \ **Category:** Factual Questions\ **Created:** [February 10, 2003, 2:44am UTC](https://boards.straightdope.com/t/how-much-anti-freeze-can-one-safely-consume/154004 "2003-02-10T02:44:17Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![Orange\_Skinner](https://avatars.discourse-cdn.com/v4/letter/o/3be4f8/32.png) [@Orange\_Skinner](https://boards.straightdope.com/u/Orange_Skinner)\ **Post date:** [February 10, 2003, 2:44am UTC](https://boards.straightdope.com/t/how-much-anti-freeze-can-one-safely-consume/154004/1 "2003-02-10T02:44:17Z")
It’s well known that animals find anti-freeze to be so appealing that they’ll lap the stuff up until they die from it…which makes me wonder, is there an amount of anti-freeze that one could safely consume, say, a teaspoonful or so, without any harmful effects? I’d really like to give the stuff a lick, but not if it’s going to make my tongue fall off. Does anybody have any knowledge in this area? Thanks, OS ---
**Author:** ![something\_clever](https://avatars.discourse-cdn.com/v4/letter/s/3bc359/32.png) [@something\_clever](https://boards.straightdope.com/u/something_clever)\ **Post date:** [February 10, 2003, 2:49am UTC](https://boards.straightdope.com/t/how-much-anti-freeze-can-one-safely-consume/154004/2 "2003-02-10T02:49:54Z")
have you sat there and thought about it? despite everyone saying it tastes sweet, i cant imagine it does… have you smelt it before? it smells really bitter… but i think animals probably do it because they’re thirsty, come on, animals are stupid, dogs eat their own… well you get the idea. ---
**Author:** ![jb\_007clone](https://avatars.discourse-cdn.com/v4/letter/j/91b2a8/32.png) [@jb\_007clone](https://boards.straightdope.com/u/jb_007clone)\ **Post date:** [February 10, 2003, 2:49am UTC](https://boards.straightdope.com/t/how-much-anti-freeze-can-one-safely-consume/154004/3 "2003-02-10T02:49:54Z")
Well they used to (and still do illegally) use it to speed up fermentation in wine. ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [February 10, 2003, 2:55am UTC](https://boards.straightdope.com/t/how-much-anti-freeze-can-one-safely-consume/154004/4 "2003-02-10T02:55:52Z")
According to [the MSDS for propylene glycol](http://www.paddocklabs.com/msdspdf/PRLYGLY.PDF), the active ingredient in antifreeze, the LD[sub]50[/sub] for a rat is between 21-33.7 g/kg. Assuming the human response to its toxicity is the same as a rat, a 91 kg (200 lb.) person would need to consume about 2 kg to have the same 50% lethality. I assume from this that a teaspoonful would not be fatal. ---
**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\ **Post date:** [February 10, 2003, 3:01am UTC](https://boards.straightdope.com/t/how-much-anti-freeze-can-one-safely-consume/154004/5 "2003-02-10T03:01:06Z")
The lowest toxic dose recorded for ethylene glycol is 1.57 grams/kg. This was for a human. Lesser amounts can cause serious kidney damage. Propylene glycol is less well studied. The lowest reported toxic dose here is 19.8 grams/kg. This was for a rat. Evidence indicates the toxic dose for a human could be lower. Definitive human data is lacking. ---
**Author:** ![FranticMad](https://avatars.discourse-cdn.com/v4/letter/f/c68b51/32.png) [@FranticMad](https://boards.straightdope.com/u/FranticMad)\ **Post date:** [February 10, 2003, 3:29am UTC](https://boards.straightdope.com/t/how-much-anti-freeze-can-one-safely-consume/154004/6 "2003-02-10T03:29:56Z")
“… propylene glycol is generally recognized as safe (GRAS) 21 {CFR 184.1666} for internal consumption and is cleared for use as direct and indirect additive in food and pharmaceuticals…” This is according to Dow Chemical. But, antifreeze also contains other chemicals to prevent corrosion. These are also toxic. [http://www.gov.nt.ca/RWED/library/eps/antifreezeguideline.pdf](http://www.gov.nt.ca/RWED/library/eps/antifreezeguideline.pdf) I suggest that there are lots of other things on the planet that you have not yet tasted, but which are far more likely to impart a benefit, or at least no harm. Suggestions: truffles, morels, edible flowers, eel, fugu, peyote (don’t swallow), steamed soybeans in the pod, fried mealworms, 4 cloves of raw garlic, Jaegermeister, tea served on a tea plantation (i.e. fresh), coffee freshly roasted from green beans (i.e. fresh), wild salmon caught within the hour, corn picked 5 minutes ago or less, freshly-pressed olive oil, limburger cheese, , a Cuban cigar, vegemite, sea urchin, 6 species of kelp. ---
**Author:** ![Orange\_Skinner](https://avatars.discourse-cdn.com/v4/letter/o/3be4f8/32.png) [@Orange\_Skinner](https://boards.straightdope.com/u/Orange_Skinner)\ **Post date:** [February 10, 2003, 3:34am UTC](https://boards.straightdope.com/t/how-much-anti-freeze-can-one-safely-consume/154004/7 "2003-02-10T03:34:28Z")
Mmm, sea urchin. Yeah, **FranticMad** , you’re probably right. I guess I’ll stick to the weird stuff that’s actually edible, if for no other reason than because I’ve come to _like_ my kidneys. Thanks, all. _goes off in search truffles of a savory nature_ ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [February 10, 2003, 3:41am UTC](https://boards.straightdope.com/t/how-much-anti-freeze-can-one-safely-consume/154004/8 "2003-02-10T03:41:22Z")
Speaking from years of experience working on cars, I can tell you that fresh ethylene glycol smells sweet, very sweet. I can understand why animals are attracted to it. In addition undiluted antifreeze can cause a chemical burns on tender skin. I have at times spilled / splashed undiluted antifreeze on my forearm and in 5-10 minutes had a red itching spot where the AF landed. YMMV, but I’m not going to replace my single malt with ethylene glycol. ---
**Author:** ![Gary\_T](https://avatars.discourse-cdn.com/v4/letter/g/3ec8ea/32.png) [@Gary\_T](https://boards.straightdope.com/u/Gary_T)\ **Post date:** [February 10, 2003, 4:34am UTC](https://boards.straightdope.com/t/how-much-anti-freeze-can-one-safely-consume/154004/9 "2003-02-10T04:34:15Z")
It won’t make your tongue fall off. The danger is when it’s ingested. Take a lick, then rinse your mouth well. ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [February 10, 2003, 5:25am UTC](https://boards.straightdope.com/t/how-much-anti-freeze-can-one-safely-consume/154004/10 "2003-02-10T05:25:22Z")
[slight hijack] Back in 94 I worked for a off-road racing team. It was very hot that summer, so I would go in to work about 4AM to work on the race car. I would always stop at the 7-11 and buy a super big glup to drink while I worked. So this one morning I am going between the work bench where I am making up the braided AN lines and the race car where I would fit, and install said lines. On about the fourth trip back and forth I grabed a super big glup cup to take a swig. It seems that the night before the guys had bleed the brakes into the handiest container around, you guessed it, a SBG cup. Not just any SBG cup but the one that was right then headed toward my open mouth. My brain was screaming **NO STOP!!!** but my arm was on auto-pilot. **BLEECH!** It took several minutes of rinsing my mouth out before I could even begin to think about work. Anyway I would not recomend that anyone put Castrol GTLMA, or antifreeze on their tongue. ---
**Author:** ![scm1001](https://avatars.discourse-cdn.com/v4/letter/s/c4cdca/32.png) [@scm1001](https://boards.straightdope.com/u/scm1001)\ **Post date:** [February 10, 2003, 10:41am UTC](https://boards.straightdope.com/t/how-much-anti-freeze-can-one-safely-consume/154004/11 "2003-02-10T10:41:10Z")
> [@](#): > > \*Originally posted by jb\_007clone \* > \*\*Well they used to (and still do illegally) use it to speed up fermentation in wine. \*\* I had always tthought that the ethylene glycol was added after fermentation to make a rough wine slightly sweeter rounder and slightly thicker ( [http://www.epicurious.com/b\_ba/b04\_bestcellars/austria.html](http://www.epicurious.com/b_ba/b04_bestcellars/austria.html) ). ---
**Author:** ![sailor](https://avatars.discourse-cdn.com/v4/letter/s/a587f6/32.png) [@sailor](https://boards.straightdope.com/u/sailor)\ **Post date:** [February 10, 2003, 11:17am UTC](https://boards.straightdope.com/t/how-much-anti-freeze-can-one-safely-consume/154004/12 "2003-02-10T11:17:49Z")
I already answered this question [here](http://boards.straightdope.com/sdmb/showthread.php?s=&threadid=158079).