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Poisonous disinfectant

Posted: Fri Jul 24, 2020 11:30 pm
by bmforre
WaPo free to read as covid related news:

at least 77 hand sanitizer products may be toxic
.. since June, the Food and Drug Administration has identified at least 77 products — including two this week — that consumers should avoid. Many of the products’ labels say they contain ethanol (also known as ethyl alcohol) but FDA tests show that they contain methanol, or wood alcohol.

Methanol can be toxic when absorbed through the skin, the agency said in an advisory, and can cause blindness. It can be lethal if ingested.

Re: Poisonous disinfectant

Posted: Sat Jul 25, 2020 6:36 am
by Woodchopper
Topic moved to this forum as it seemed more appropriate here

Re: Poisonous disinfectant

Posted: Sat Jul 25, 2020 8:49 am
by Brightonian
Oh great. And I was congratulating myself the other day for getting a 500ml container of hand gel for five quid. It says it "kills 99.999% of bacteria" - wow, look at all those nines! And it's got tea tree in as well! No idea whether to trust it or any others now.

Re: Poisonous disinfectant

Posted: Sat Jul 25, 2020 9:57 am
by Bird on a Fire
The article's from the US, about products manufactured in Mexico. Is the same likely to be to true of products sold in UK/Europe, which are presumably manufactured somewhere else?

Re: Poisonous disinfectant

Posted: Sat Jul 25, 2020 10:32 am
by shpalman
Brightonian wrote:
Sat Jul 25, 2020 8:49 am
Oh great. And I was congratulating myself the other day for getting a 500ml container of hand gel for five quid. It says it "kills 99.999% of bacteria" - wow, look at all those nines! And it's got tea tree in as well! No idea whether to trust it or any others now.
Just don't drink it.

Re: Poisonous disinfectant

Posted: Sat Jul 25, 2020 11:06 am
by Martin Y
Is the amount of methanol you might absorb from hand gel actually a significant hazard? If I clean something with a rag or tissue wet with methylated spirits (or, what do they call it in the US, denatured alcohol?) am I poisoning myself by absorption?

<ETA> I get that products which say they contain ethanol and actually contain methanol too should be withdrawn because people will drink them, but the skin absorption thing sounds a bit like OTT scaremongering.

Re: Poisonous disinfectant

Posted: Sat Jul 25, 2020 11:43 am
by Brightonian
shpalman wrote:
Sat Jul 25, 2020 10:32 am
Brightonian wrote:
Sat Jul 25, 2020 8:49 am
Oh great. And I was congratulating myself the other day for getting a 500ml container of hand gel for five quid. It says it "kills 99.999% of bacteria" - wow, look at all those nines! And it's got tea tree in as well! No idea whether to trust it or any others now.
Just don't drink it.
Hmmm...calculates...
cider...5% alcohol...2L bottle...£2.05...21p per unit
gel...70% alcohol...500ml bottle...£5...14p per unit

Re: Poisonous disinfectant

Posted: Sat Jul 25, 2020 12:35 pm
by shpalman
Martin Y wrote:
Sat Jul 25, 2020 11:06 am
Is the amount of methanol you might absorb from hand gel actually a significant hazard? If I clean something with a rag or tissue wet with methylated spirits (or, what do they call it in the US, denatured alcohol?) am I poisoning myself by absorption?

<ETA> I get that products which say they contain ethanol and actually contain methanol too should be withdrawn because people will drink them, but the skin absorption thing sounds a bit like OTT scaremongering.
On the other hand, things which contain ethanol but don't want to be taxed as alcoholic beverages need to have the alcohol denatured in some way to render it undrinkable.

ETA I would expect that the ones sold here use something to make it unpleasant rather than actually poisonous, and that this might not work in places where the alcoholism is more desperate.

And no I don't expect that there's a significant danger from skin contact, and it's only sort of implied in the article without being explicitly stated.

Re: Poisonous disinfectant

Posted: Mon Jul 27, 2020 7:12 am
by jimbob
shpalman wrote:
Sat Jul 25, 2020 12:35 pm
Martin Y wrote:
Sat Jul 25, 2020 11:06 am
Is the amount of methanol you might absorb from hand gel actually a significant hazard? If I clean something with a rag or tissue wet with methylated spirits (or, what do they call it in the US, denatured alcohol?) am I poisoning myself by absorption?

<ETA> I get that products which say they contain ethanol and actually contain methanol too should be withdrawn because people will drink them, but the skin absorption thing sounds a bit like OTT scaremongering.
On the other hand, things which contain ethanol but don't want to be taxed as alcoholic beverages need to have the alcohol denatured in some way to render it undrinkable.

ETA I would expect that the ones sold here use something to make it unpleasant rather than actually poisonous, and that this might not work in places where the alcoholism is more desperate.

And no I don't expect that there's a significant danger from skin contact, and it's only sort of implied in the article without being explicitly stated.
Meths in the UK has changed its formulation in the UK - in 2013:
From Wiki
Formulations
Diverse additives are used to make it difficult to use distillation or other simple processes to reverse the denaturation. Methanol is commonly used both because its boiling point is close to that of ethanol and because it is toxic. Another typical denaturant is pyridine. Often the denatured alcohol is dyed with methyl violet.[8]

There are several grades of denatured alcohol, but in general the denaturants used are similar. As an example, the formulation for completely denatured alcohol, according to 2005 British regulations was as follows:[9]

Completely denatured alcohol must be made in accordance with the following formulation: with every 90 parts by volume of alcohol mix 9.5 parts by volume of wood naphtha or a substitute and 0.5 parts by volume of crude pyridine, and to the resulting mixture add mineral naphtha (petroleum oil) in the proportion of 3.75 litres to every 1000 litres of the mixture and synthetic organic dyestuff (methyl violet) in the proportion of 1.5 grams to every 1000 litres of the mixture.

The European Union agreed in February 2013 to the mutual procedures for the complete denaturing of alcohol:[10]

Per hectolitre (100 L) of absolute ethanol: 3 litres of isopropyl alcohol, 3 litres of methyl ethyl ketone and 1 gram denatonium benzoate.

There was quite a lot of discussion in camping forums about this

Re: Poisonous disinfectant

Posted: Mon Jul 27, 2020 8:25 am
by science_fox
Methanol is one of those odd lab 'chemicals' that's widely used especially in my building by biologists* without much care, but the MSDS is pretty strict - "https://beta-static.fishersci.com/conte ... 25426A.pdf"

You will absorb it through the skin and it will have effects if you do so. A few ml probably isn't too bad, as the LD50 is 15g/Kg so you'd need a 1 L exposure to be at risk of dying. If you're using a gel many times a day, every day I would change product.





* "all those (other) risk assessments are just like methanol and I use that all the time" - to which my reply was read the RA for methanol properly!