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Determination of percentage of Methanol in an Alcohol based hand sanitiser

Note: I am looking for advice on a chemical test – not a sermon.
I expect that this is entirely on topic in this forum, downvotes and sermon comment notwithstanding.

More than about 5% of Methanol in alcohol based hand sanitisers indicates that corners have been cut during manufacture and that the product should be avoided.

I’m looking for an easy test to determine the approximate percentage of Methanol in an Ethanol / Methanol hand sanitiser mix. Many hand sanitisers may contain small percentages of Methanol (typically in the 1% – 5% range) and this is acceptable. Anything over 5% I’d like to avoid. Much over 5% (say 10% +) I’d like to be very clearly distinguished. If actual approximate percentage can be indicated, so much the better.

Ideally I’d like a test with either low cost, simple to use, readily available non-hazardous reagents (one can hope) or failing that, something that can be prepackaged for easy use by the unskilled.

In web searches I found a range of tests for Methanol but most were not very quantitative and most were not intended to work in an ethanol-methanol mixture.


Background: Added:

Some guy y’know said:

Using disinfectants outside of a heathcare environment is still nonsense in the year 2020. Using disinfectants of questionable provenience is simply hazardous. DonĀ“t do it.

The use of hand sanitisers is well covered in recommendation documents from regulatory authorities in many administrations and by internationally relevant bodies. Sanitisers are sold under regulatory guidelines which if followed would guarantee their safety when used appropriately. In the US many out of specification brands are being sold which are indistinguishable from those which comply. Several of the largest US sellers have been selling out of spec product. There is no way to determine provenance based on labelling.

While the use of soap and water is often a good or even superior solution it is incorrect to suggest that the use of sanitisers in general applications is nonsense.

In this instance I am interested NOT in their efficacy or application but re their specific bonafides with respect to a crucial component which is known to be used in excessive and illegal amounts in some cases.

I’m an engineer. Sanitisers are sold by a wide range of manufacturers and repackagers. I read labels, note sources, note claimed contents and viscosities and residence times and more.

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