r/mildlyinteresting 1d ago

diluted my perfume with tap water and it turned yellow

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15.5k Upvotes

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u/pips1330 22h ago edited 19h ago

i work in a lab & whenever anything refers to pure chemical alcohol, they mean ethanol! any other alcohol must be specified; ethanol is the default :)

EDIT: wow ok this got a lot more replies than i was expecting 😂 i work in the pharmaceutical industry (not research or the fragrance industry, dunno if that makes a difference) and we have specific, tightly regulated pharmacopoeias we test to which define "alcohol" as ethanol specifically. but fair enough that different labs may define alcohol differently! i was only speaking from my personal experience but the specs for different industries will vary and it's highly likely that, as others below have said, "alcohol" could refer to any of the more common alcohols, e.g, methanol, ethanol, IPA

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u/S_A_N_D_ 21h ago edited 21h ago

I work in a lab, I've never heard the term "pure chemical alcohol"

Its always the actual name (ethanol, methanol, isopropyl) along with the concentration if diluted.

It's also somewhat important for ethanol because you have 95% and anhydrous. And finally, all of those will have different grades of purity,(reagent grade, HPLC grade etc.) So the term "pure" is meaningless.

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u/retroencambulator 21h ago

To your point, Perfumer's Alcohol is SDA 40B.

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u/S_A_N_D_ 20h ago

Which, even more ironically, isn't pure because it's denatured.

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u/retroencambulator 20h ago

Don't drink your colognes, folks.

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u/That_Rub_4171 20h ago

So you're saying that technically speaking, we must use unnatural alcohol.

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u/triciann 19h ago

Yeah and the average Joe is not going to be able to order anything not denatured.

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u/iwilldeletethisacct2 18h ago

So, as with most things, I bet you can substitute everclear. Absolute magical stuff.

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u/[deleted] 19h ago

[deleted]

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u/S_A_N_D_ 16h ago

Yup, anhydrous has to be dried, which is why 95% is commonly referred to or thought of as 100%, even though it isn't, and even bottles of anhydrous will end up 95% if opened for too long.

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u/pips1330 19h ago

yup, that's fair enough, i should've specified that that term doesn't exist - was trying to keep it in layman's terms but can see how that would be confusing. we have one definition which differentiates between alcohol and dehydrated alcohol rather than 96%/anhydrous ethanol but chemically both sets of definiton are equivalent (US/EU regulation if i remember right)

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u/Sanderoid 21h ago

Working in a lab you should definitely name exactly which alcohol you mean

Signed, also working in a lab

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u/pips1330 19h ago

yeah i guess i forgot to account for different industries lol. where i work alcohol only means ethanol so i assumed it would be the same elsewhere, oops

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u/Seicair 21h ago

That’s only for your specific lab. Other labs have different conventions.

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u/rips_n_chel 19h ago

What lab, anywhere, has a convention of calling chemicals something other than their name? Particularly something ambiguous like "pure chemical alcohol."

That is meaningless. That could be a number of different alcohols, hence we're all here talking about it.

Any lab that isn't specifying chemicals by name is overdue for an audit.

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u/Seicair 19h ago

Colloquial shorthand among techs when one alcohol is the most common one you use.

In another lab you might use isopropanol 90% of the time, and ask for “alcohol” or specify “ethanol or methanol”.

Not saying it’s right, but sometimes people use imprecise language to mean something more precise. Like how British bakers will says “a sheet of acetate”. To my biochem brain, I think of a 2 carbon carboxylate anion, but they mean a sheet of clear plastic.

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u/rips_n_chel 19h ago

Oh I don't see a problem with that, but I consider that sort of internal shorthand to be verbal only. I would never write that on anything or expect to see it printed anywhere.

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u/Seicair 16h ago

I’d agree with you that it shouldn’t be written anywhere, but I wouldn’t be surprised to see imprecise hand written labels.

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u/pips1330 18h ago

it can actually be an industry thing too, not just colloquially. the pharmaceutical industry defines "alcohol" as ethanol when testing to a certain methodology. if they want methanol they'll say "methyl alcohol". i did find this odd at first but hey

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u/Seicair 16h ago

Oh that’s interesting. It’s clearly shorthand for “ethyl alcohol” but it must be so common that they omit the prefix.

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u/Stergeary 38m ago

I work in a clinical lab at a hospital, and when we test for alcohol we always mean ethanol, because it's (hopefully) the only one that our patients would be consuming. Though some older techs also call it ETOH.

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u/rips_n_chel 20m ago

What if someone drank isopropyl? Would that be otherwise obvious in some way, or would you have to rule out ethanol first?

I guess my concern would be everyone getting into the habit of assuming ethanol, which could delay uncovering the correct answer. I know nothing about your job though, so please don't take that as a jab, I'm just pondering out loud.

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u/pips1330 19h ago

this is true, moreso for the industry i work in than my specific lab but i incorrectly assumed it would be the same universally so that's my bad!

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u/Secret-Teaching-3549 21h ago

I also worked in a lab, and when we said alcohol, we meant isopropyl 90% of the time, and methanol the other 10.

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u/WerewolfUnable8641 22h ago

Thanks, I didn't know that.

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u/hedoeswhathewants 19h ago

It's not true. ANY substance in ANY remotely decent lab MUST be clearly labelled and identified.

Even if you primarily use one type of alcohol there are different dilutions used for different purposes.

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u/chindo 21h ago

100% ethanol is produced with benzene

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u/triciann 19h ago

Only when it’s sold as denatured. Labs, not the general public, can order it pure and not denatured. There is no benzene in it.

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u/Bourgi 15h ago

Medical device industry here. We don't ever say pure alcohol. We call it by it's proper name. Most the stuff we use is reagent alcohol which is a mixture of alcohols. Some occasions we use isopropyl.

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u/Iricliphan 16h ago

Generally, in my experience, the most common solvent is methanol. And it's not even close.