Safety of using methanol in alky stoves...

[Dirtygaiters]

I've become fed up with 91% isopropyl alcohol and am switching to methanol or denatured alcohol. My question to alcohol stove people who use these fuels, what sort of precautions do you take to prevent methanol from making contact with your cooking pot/food-related surfaces?

I've always used isopropyl until now because I have serious reservations about storing a bottle of poison, or a stove previously fill with poison, inside my cooking pot (and I like to be able to fit all my stove materials inside my pot). However, maybe denatured alcohol has a low enough concentration of methanol to render its storage in a fuel bottle inside a cooking pot safe? Any input on this? Should I just store the fuel bottle at a different location?

[peanuts]

dirtygaiters, you don't have to worry about the denatured alcohol. once is used ordor and residu is gone. why were you using iso in the first place is not the best choice for alchy stoves. when using denat just make sure is in a level surface and don' get to close. i store a 2oz bottle in my pot for an overnite. no problem either. prescriptions cough bottles work great.

[Uncle Silly]

Methanol, straight up or denatured, is much more efficient than Isopropyl. Isopropyl is just as unsafe to imbibe, so why the concern about poisonousness? We're talking quantities: if you drink either denatured methanol or isopropyl like you'd drink bourbon, you're gonna make yourself sick. If, on the other hand, a drop gets onto your cookpot, and from there into your food, neither is really anything to worry about.

I use denatured almost exclusively. I'll only use isopropyl if that's the only fuel I can find: it doesn't heat as well and creates far too much soot (signs of inefficient combustion). I usually hike with a large (16-20oz) fuel bottle that won't fit in my cookset anyways, but if I were to use a small fuel bottle that fit in my cookset (with my stove and its accoutrements), I wouldn't have any concerns about fuel contacting the cooking surfaces.

And maybe your concern is warranted, but it seems common sense should apply. If methanol on food surfaces is really that bad, then storing your fuel separately would help; and in case of an inadvertant contact, just rinse well and dry. If you can't rinse well, let the methanol dry or burn it off, then wipe down with a damp cloth. Ta-da, problem solved. (Or.... am I missing something? Any chemistry folks care to chime in?)

[Skidsteer]

I've become fed up with 91% isopropyl alcohol and am switching to methanol or denatured alcohol. My question to alcohol stove people who use these fuels, what sort of precautions do you take to prevent methanol from making contact with your cooking pot/food-related surfaces?

I've always used isopropyl until now because I have serious reservations about storing a bottle of poison, or a stove previously fill with poison, inside my cooking pot (and I like to be able to fit all my stove materials inside my pot). However, maybe denatured alcohol has a low enough concentration of methanol to render its storage in a fuel bottle inside a cooking pot safe? Any input on this? Should I just store the fuel bottle at a different location?

That's an excellent topic for discussion. I debate with myself about it all the time.

I guess it comes down to what you are comfortable with and what you have faith in.

I have a lot of faith in soda bottles of various sizes fitted with soda bottle caps(with actual gaskets) because I've never had one leak. I'm not just talking about hiking either. I carry a cookset in my truck with me when I travel(@ four nights per week) and use it to make simple whole wheat pasta/salmon dinners when I'm too lazy to go out. I store a fuel bottle inside the pot and it spends all day being bounced around, upended, and subjected to wild fluctuations in temperature. Hasn't leaked in the six plus years I've been on the road. I have a lot of confidence in it.

That being said, your choice must be made by you because you have to deal with the consequences.

I would love to hear from Chem guys and gals(hint, hint, DWM)about strategies to detoxify spills and boo boos.

[Dirtygaiters]

I think that methanol is soluble in water so if it did spill in the cookpot, it would wash right out and the surface would be safe to eat out of. I think... I just had always heard that methanol is highly poisonous and causes blindness if you drink it. Isopropyl is rubbing alcohol. Yeah it will make you sick if you drink it, but it's apparently safe enough to use on your skin without risk of blindness, so that's less of a danger in my book than methanol is. Maybe methanol is not as highly toxic as I thought? I don't know. That's why I asked the question. I assume that all these thru hikers using it as fuel aren't going blind left and right, but I don't know how they are storing it, if they have reservations about storing a bottle of methanol inside a cookpot or just keep it any place without the concern I have. :-/

[Uncle Silly]

Like I said, we're talking quantities. If you replace your bourbon with either denatured or isopropyl, you're gonna get sick. If you drink enough methanol, blindness is one potential result.

Isopropyl is considered safe for topical uses, but note the warnings on the bottle that say do not drink. I think there's a difference chemically that makes methanol much more readily absorbed through the skin, which is why denatured talks about taking care about skin contact, ventilation, etc. Denatured is often used industrially as a solvent; in large doses, daily use, etc, yes, you want to take care.

But spilling a couple of drops on your finger, as you measure out an ounce or so for your alkie stove, isn't going to do any measurable damage; neither is ingesting small quantities. And both methanol and isopropyl will evaporate quickly; if you do spill it on your cook surface, cleanup can be as simple as waiting a few minutes. (Here's where my knowledge ends: does denatured contain toxic contaminants that may be left behind after evaporation?)

[Skidsteer]

It's toxic alright. And it says right on the bottle that it cannot be made non-poisonous. But that's not the same as saying you can't wash it off a surface safely.

We need some Chem types!

[JAK]

It might be worth distilling your own 99% ethanol camp fuel.
Of course resupply on a thru-hike would be difficult.

It would be the perfect fuel though, if only it were legal.

[budforester]

That Isopropanol you're using is toxic, too. I usually use denatured (label on the paint aisle reads SLX), and I have more concerns about its formaldehyde vapors than its methanol content. I go along with what's been recommended for drips and spills: rinse, burn, or dry it off and go ahead with dinner.

[Dances with Mice]

Right now at work I'm doing a truckload of extractions using isopropyl - our production facility is cranking out 16 samples per hour 10 hours per day and we can analyze 14 per hour tops and I'm on salary so there ain't gonna be no 10 hour days, Sparkie. So if you can do math better than our production folks you can see that the harder we work the further we get behind.

For these isoprop extractions I'm wearing protective eyewear, vinyl gloves, and a lab coat. OK, so forget the lab coat because it's way too hot here right now but the gloves and glasses aren't optional. For methanol extractions it'd be the exact same program.

So I'm up to my elbows in this stuff, literally, from right after my morning coffee until lunch, then again from lunch to quitting time. If I use the bathroom sometime in there I'll strip off the gloves and wash my hands before and after.

But I throw my stove in my cookpot without a second thought. These alkies are really volatile. There's no chance of any isoprop or meth hanging around at normal temps from a couple drops of stove residue. Zero, zip, zilch, nada. No way Jose'. It'd be like leaving a damp washrag outside in Las Vegas in August then coming back at night and expecting it to still be wet. It ain't gonna happen.

But let's say there's some minute amount of alcohol hanging around in spite of all the laws of physics. All these alkies will dissolve in water. A single rinse will remove all traces.

So chunk your stove into your pot and stash it in your pack. No problem. Mother Nature says so.

If you disagree then take it up with her.

[booney_1]

This is a good topic. I don't worry so much about getting it on my pots, but it's awfully hard to pour and handle without getting some on your fingers. Your skin can readily absorb this stuff. The MSDS (material safety data sheet) for denatured alcohol says to avoid skin contact and wear gloves. The safest thing to do would be to buy Ever-Clear, but that is pretty expensive...but then if you got snake-bit you'd be all set.

(also some denatured alcohol is made by adding petroleum products like gasoline or beneze...these are very hazardous)

[Uncle Silly]

Again, the MSDS says that because it IS a risk, and because the MSDS is designed to be the safety handbook for situations like DWM's work lab. (Thanks for chiming in, DWM!) It doesn't consider light contact like we're talking about.

For the two or three times a day I'll use my stove (once or twice for breakfast, once or twice for dinner), I don't consider there to be any real risk. The precautions I do take: 1) keep the fuel bottle away from the stove, campfire, candle, in-use cigarette lighter, etc; and 2) try to exhale while filling the stove or refilling the bottle. These are basically the same precautions I take with my white gas fuel bottle, and for the same reasons.

[minnesotasmith]

Sure, both are highly unwise to drink, but that's hardly the whole story. Methanol absorbs through the skin, to the point that over time it can be a hazard. As it tends to destroy the liver and central nervous system, especially eyesight, that's pretty serious. By comparison, isoprop is actually approved for topical (skin) use.


Plus, even if not swallowed or spilled on the skin, and only breathed in, methanol is still more toxic than isopropyl. OSHA has given methanol a TWA (time-weighted average) vapor exposure legal maximum of 200 ppm, vs. 400 for isopropyl, so even its vapors are considered twice as bad as those from isopropyl.

I believe that denatured ethanol is the best all-around alcohol fuel for hikers.

Sources:

Methanol material safety data sheet: http://avogadro.chem.iastate.edu/MSDS/methanol.htm

Isopropyl material safety data sheet: http://64.233.169.104/search?q=cache:-PeaeO7y3NEJ:www.telecheminternational.com/IPA_Reagent_ACS.PDF+MSDS+isopropyl+TWA&hl=en&ct=clnk&cd=1&gl=us

[booney_1]

The last post did a good job describing the dangers of methanol. My (poorly made) previous point was that many suppliers of denatured alcohol, denature it by adding methanol. So in my mind it is almost as dangerous as pure methanol. It is difficult to know how much exposure is too much.

[hopefulhiker]

I like the little shampoo bottles with the flip top to hold alcohol.. It is a lot neater that way. Anti gravity gear has them.... I used that HEET from service stations. It worked OK.. I was just real careful not to get it in my food...

[minnesotasmith]

The last post did a good job describing the dangers of methanol. My (poorly made) previous point was that many suppliers of denatured alcohol, denature it by adding methanol. So in my mind it is almost as dangerous as pure methanol. It is difficult to know how much exposure is too much.

Normally has about a maximum of 5% methanol. Often other chemicals (mostly less hazardous than methanol) are used as part of that 5%, so there may be much less than 5% methanol in ethanol that has been denatured with it. Thus, denatured ethanol is normally substantially less hazardous to the hiker using it as stove fuel than is pure methanol.

[Uncle Silly]

From wikipedia:


Methylated spirit (Meths or denatured alcohol — but not Rubbing alcohol, which is different) is ethanol which has been rendered toxic or otherwise undrinkable, and in some cases dyed. It is used for purposes such as fuel for spirit burners and camping stoves, and as a solvent. Traditionally, the main additive was 10% methanol, which gave rise to its name, but this is not always the case now. There are diverse industrial uses for ethanol, and therefore literally hundreds of recipes for denaturing ethanol. Typical additives are methanol, isopropanol, methyl ethyl ketone, methyl isobutyl ketone, denatonium, and even (uncommonly) aviation gasoline.

and


The regulations relating to denatured alcohol in the United States may be found at 27 CFR part 20.

and relating to toxicity:


It is not the methanol itself that is toxic, but the accumulation of its metabolites, formaldehyde and formic acid. Because the metabolic pathways for ethanol and methanol share a common enzyme, alcohol dehydrogenase, ethanol can be used to treat methanol poisoning by blocking the enzyme until the body can excrete enough methanol through the lungs and skin. (In a documented case, a shipworker poisoned while cleaning out a methanol tank was successfully treated with administration of a good portion of the liquor in the ship's "medicine chest.")

Now that's my kind of first aid!!

[atraildreamer]

Buy screw cap bottle of Heet Yellow Methanol Dry Gas.

Pour methanol into stove, not cookpot.

Light...cook food...eat food...stop worrying so much. There is so much more stuff in the world that is out to kill you! :eek: :D:banana

[Uncle Silly]

Pour methanol into stove, not cookpot.
:banana

THAT's what i've been doing wrong all these years!!