Is Denatured Alcohol Safe for Use on Face Masks?

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Denatured alcohol is commonly used in medical facilities for sanitation, but its safety for use on face coverings is debated. Concerns arise regarding the presence of methanol and other denaturants, which may not fully evaporate and could be harmful when inhaled or in contact with skin. The composition of denatured alcohol varies by region; in the EU, it often contains isopropanol and butanone, while in the US, it typically includes methanol or other toxic substances. Studies indicate that using denatured alcohol on N95 masks can significantly reduce their filtration efficiency. Alternatives like UV light, steam, or dry heat are recommended for sanitizing masks. Users are advised to carefully check the specific formulation of denatured alcohol before use, as not all types are safe for cleaning personal protective equipment (PPE).
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I know that medical facilities will use denatured alcohol to sanitize counters, sinks, etc. But can you use it to sanitize something that will be worn over the face? Do the fumes evaporate at all or do they stay present?

Thanks much
 
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Denatured alcohol has methanol in it. It evaporates too. I am not sure I'd want to wear a mask that has had denatured alcohol in it until it had completely evaporated.
 
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How long is that? I know ipa is pretty fast but i have never used denatured alcohol. So I am am completely unfamiliar with it haha
 
When it's dry.
 
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Vanadium 50 said:
When it's dry.
Bet.
 
Vanadium 50 said:
Denatured alcohol has methanol in it. It evaporates too.

That depends on the origin. In the EU for example it contains no methanol but isopropanol, butanone and denatonium benzoate. Thus, you cannot be sure that everything evaporates, unless you check what you are actually starting with.
 
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In the US, 'denatured' alcohol just means not pure ethanol. More specifically, usually it means inclusion of wood alcohol (methanol), or inclusive of another 'denaturant' which renders it entirely impotable or at least much more toxic than plain ethanol, which itself is rather toxic.
 
DrStupid said:
In the EU for example it contains no methanol but isopropanol, butanone and denatonium benzoate.
That's incorrect. We have the same kind denaturated alcohol as elsewhere, based on ethanol.

See https://eur-lex.europa.eu/legal-content/en/ALL/?uri=CELEX:31993R3199
Commission Regulation (EC) No 3199/93 of 22 November 1993 on the mutual recognition of procedures for the complete denaturing of alcohol for the purposes of exemption from excise duty
 
DrClaude said:
That's incorrect. We have the same kind denaturated alcohol as elsewhere, based on ethanol.

See https://eur-lex.europa.eu/legal-content/en/ALL/?uri=CELEX:31993R3199
Well, to be clear, I'm confident that you know that ethanol is what's being denatured; it's not to be confused with a denaturant; looking at your link, I see many different denaturants, the primary one being wood alcohol, i.e. methanol, but there are many others, including MEK.

I have a fun true story about MEK (methyl-ethyl-ketone) -- caution: MEK is very strong stuff and please don't mess with it if you don't very surely know what you're doing.

I climbed up the tree next to the street light next to my house. The city had replaced the glass globes atop the the lamp poles with plastic. I took an el marko pen and drew cartoon images all over the plastic globe. When they advertised that marker as permanent they weren't kidding.

When my Dad arrived at home he immediately recognized my handiwork as mine and ordered me to clean it up. Nothing we had in the house made the slightest impact. Bleach, scouring powder, etc. were completely ineffective.

Then I got what I thought was a bright idea. The father of my friend across the street was an art professor. I figured he probably had some MEK for cleaning paintbrushes, and sure enough, he did. He gave me a babyfood jar of it, and sure enough, I was able to instantly wipe the globe clean and pristine. I hosed it off and reset it back on the pole. My Dad looked at it and approved and reduced my punishment (less time deprived of privileges).

So here's the fun part: the MEK broke all the hydrocarbon bonds in the plastic, and by late the next morning, the globe had shriveled like an expired helium balloon, but the Street Department saw it, got their WTF moment, and collected it as a souvenir and replaced it before my Dad got home -- lucky me . . .
 
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DrClaude said:
That's incorrect. We have the same kind denaturated alcohol as elsewhere, based on ethanol.

See https://eur-lex.europa.eu/legal-content/en/ALL/?uri=CELEX:31993R3199

This version of (EC) No 3199/93 is outdated. It has been amended by (EU) 2017/1112 (see https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:32017R1112&from=DE). The current consolidated version (see https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX:01993R3199-20181223) says:
I. The common denaturing procedure for completely denatured alcohol employed in Belgium, Bulgaria, Czech Republic, Denmark, Germany, Estonia, Ireland, Greece, Spain, France, Italy, Cyprus, Latvia, Lithuania, Luxembourg, Hungary, Malta, the Netherlands, Austria, Poland, Portugal, Romania, Slovenia, Slovakia and Finland:

Per hectolitre of absolute ethanol:
- 1,0 litre isopropyl alcohol,
- 1,0 litre methyl ethyl ketone,
- 1,0 gram denatonium benzoate.

UK, Croatia and Sweden are using other amounts but the same ingredients.

Only Greece still has an additional procedure using methanol with the following composition:
Per hectolitre of hydrated alcohol of 93 % volume, the following substances are added:
- 2,0 litres methanol,
- 1,0 litre spirit of turpentine,
- 0,50 litre lamp oil,
- 0,40 gram methylene blue.
 
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  • #11
I mixed up in my head posts #6 and #7 when replying; apologies for that.

Thank you @DrStupid for clarifying the current rules. It confirms that
DrStupid said:
In the EU for example it contains no methanol but isopropanol, butanone and denatonium benzoate.
didnät give the proper picture of what denaturated alcohol you can find in the EU.
 
  • #12
DrClaude said:
It confirms that
DrStupid said:
In the EU for example it contains no methanol but isopropanol, butanone and denatonium benzoate.
didnät give the proper picture of what denaturated alcohol you can find in the EU.

I referred to the EU - not just to single member states. And that was just an example for a composition other than ethanol + methanol. Sorry, if that wasn't clear enough.

My point is, that we do not have the same kind denaturated alcohol as elsewhere (no matter what "we" or "elsewhere" means). Just acting on the assumption that methanol (and only methanol) is used for denaturation is not advisable. Depending on local rules there are a lot of other possible ingredients. Some of them do not evaporate and it is at least not obvious if they are safe for the skin. If somebody wants to use denaturated alcohol to sanitize something that will be worn over the face (that's what we are talking about) he should better check what his particular version actually contains.
 
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You didn't say what type of face covering. If it's an N95 mask there is a published study (included in this page) that indicates that it's a bad idea. It's not that ethanol won't kill the virus but rather that it can reduce the filtration efficiency by almost half. They recommend alternatives (UV; steam; or dry heat at 70°C). One might extrapolate these methods to other types of face coverings.
 
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  • #14
DrStupid said:
My point is, that we do not have the same kind denaturated alcohol as elsewhere (no matter what "we" or "elsewhere" means).
Get the kind with denatonium benzoate. If that’s all it has as a denaturant then a simple distillation renders it drinkable, er... good for use in contact with skin.
 
  • #15
chemisttree said:
Get the kind with denatonium benzoate. If that’s all it has as a denaturant then a simple distillation renders it drinkable, er... good for use in contact with skin.

It also contains isopropanol and butanone which can't be removed by destillation (azeotrope).
 
  • #16
DrStupid said:
That depends on the origin. In the EU for example it contains no methanol but isopropanol, butanone and denatonium benzoate. Thus, you cannot be sure that everything evaporates, unless you check what you are actually starting with.
Everything in that list evaporates except for the denatonium salt, which is non-volatile (and is probably only present in the ppm range anyway).
 
  • #17
TeethWhitener said:
Everything in that list evaporates except for the denatonium salt

But that list does not fit to every denatured alcohol.
 
  • #18
DrStupid said:
That depends on the origin. In the EU for example it contains no methanol but isopropanol, butanone and denatonium benzoate. Thus, you cannot be sure that everything evaporates, unless you check what you are actually starting with.
You can easily purchase pure denatured alcohol in the US at most home improvement stores...however you have to read the labels carefully to ensure that you are purchasing pure denatured alcohol not a mixture of methanol and alcohol. For example the "Clean Strip" brand with a GREEN label is pure denatured alcohol and states that fact on the contents label. Among other uses, pure denatured alcohol is a basic requirement for the manufacture of the Shellac wood finish (which is made from the excretions of the female Hemiptera to help the insect attach to the bark of a tree). IF you have any doubts as to how dangerous breathing any of these alcohol fumes is, please read the MSDS (Material Safety Data Sheet) that is required to be available for all "listed" materials that travel in any conveyance (trucks, rail, aircraft, etc.) anywhere in the US. Please do not consider this a safe item for cleaning your PPE. Brain damage and other neurological issues are inevitable. Search on MSDS and specify the brand name and label listing.
 
  • #19
JT Smith said:
You didn't say what type of face covering. If it's an N95 mask there is a published study (included in this page) that indicates that it's a bad idea. It's not that ethanol won't kill the virus but rather that it can reduce the filtration efficiency by almost half. They recommend alternatives (UV; steam; or dry heat at 70°C). One might extrapolate these methods to other types of face coverings.
Please do not consider cleaning any PPE with denatured alcohol-either pure or mixed with other alcohols. This could be quite dangerous. Refer to the MSDS (material safety data sheet) for this product to understand how dangerous this could be; i.e., neurological damage is likely. Among other uses, the MSDS is used by first responders when there is a spill of the product during transportation or in a manufacturing spill or contamination.
 
  • #20
cosmicrayray said:
You can easily purchase pure denatured alcohol in the US at most home improvement stores...

What do you mean with "pure denatured alcohol"?
 
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  • #21
DrStupid said:
What do you mean with "pure denatured alcohol"?

As I recall denatured alcohol is adulterated by definition.

Can "pure denatured alcohol" be use for time travel?

BoB
 
  • #22
Vanadium 50 said:
I am not sure I'd want to wear a mask that has had denatured alcohol in it until it had completely evaporated.
so am I, and I think whisky is better to sanitize a mask and there is no need to wait until it evaporates
 
  • #23
wrobel said:
so am I, and I think whisky is better to sanitize a mask and there is no need to wait until it evaporates

I prefer vodka with an alcohol content of at leat 70%.
 
  • #24
DrStupid said:
What do you mean with "pure denatured alcohol"?
I am neither a chemist or an industry expert on this subject but I regularly use this product in my manufacturing processes. Exclusive of a chemist's view of the material, industrial and home users can't reliably depend on the general product label "Denatured Alcohol" because there are so many different "kinds" or "mixes" and even colors available (green or purple in some countries). For clarity, denaturing does not remove something physical from ethanol, it does, however remove the property that makes it palatable by adding substances that make it extremely distasteful, often poisonous and mostly difficult to consume. Other non-food grade alcohols are often added along with denaturing agents to reduce the cost of the product by reducing the amount of ethanol. This most means adding methanol. Denatured alcohol products are generally only around 25% ethanol and about 75% methanol and are often used as heating fuels, lamp fuel and paint thinner. Only enough ethanol is included so the resulting mixture effectively softens paint. Unadulterated Ethanol (ethyl alcohol) is safe to drink, but it's denatured cousin is obviously not. My reference to pure "denatured" alcohol is a product that is 100% ethanol and contains no denaturing agent (think beverage-grade 191-proof ethanol). Maybe I could have said it better, but the problem here is that you can purchase a product that is pure ethanol (not denatured) and is sold under the label of Denatured Alcohol. I wouldn't mix drinks with it because it is not packaged or handled as a food grade product. Aside from quickly displacing oxygen in your lungs, one of the other nasty side effects of using ethanol for cleaning PPE is that it is a "hot" solvent and easily melts plastics, destroys painted surfaces, leaves shiny finished surfaces dull and sticky and most importantly, makes a mess of my finger nail polish, even the acrylic variety! Oh...and don't spray it on your sun glasses!
 
  • #25
cosmicrayray said:
My reference to pure "denatured" alcohol is a product that is 100% ethanol and contains no denaturing agent (think beverage-grade 191-proof ethanol). Maybe I could have said it better, but the problem here is that you can purchase a product that is pure ethanol (not denatured) and is sold under the label of Denatured Alcohol.

That's hard to believe. Do you have a reference?
 
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