Sciencemadness Discussion Board - worst stench

worst stench

DNA - 9-4-2008 at 12:40

I would like to know which compound has the worst smell.
I was doubting between the following.
If you know a compound that smells far more then the ones listed below please let me know.
Preferably a smell that lasts really long.

ScienceGeek - 9-4-2008 at 12:46

According to the Guiness book of records, ethanethiol (ethyl mercaptan) is the smelliest substance in existence. I am happy not to have smelled this substance, and to quote the book: "It has an ooze like a mixture of rotten cabbage, garlic, onion, burnt toast and sewer- gas. "

In my personal experience, Hydrogen Sulfide is the worst of the ones I have smelled.

chemkid - 9-4-2008 at 12:55

I have heard the hydrogen sulfide has the lowest scent threshhold.

Ozone - 9-4-2008 at 12:55

http://www.sciencemadness.org/talk/viewthread.php?tid=1216&a...

happy wafting!

O3

evil_lurker - 9-4-2008 at 14:01

Pyridine is the worst stuff I have ever had the pleasure of sniffing.

joeflsts - 9-4-2008 at 15:48

Some time ago I was heavy into esters. I bought some butyric acid to experiment with and when I opened it my rather sensitive stomach kicked in..... I eventually made the ester and I lost a few lbs in the process.

Joe

chemrox - 9-4-2008 at 19:58

I had spilled the butyric acid in the stockroom where I worked and cleaned it up. I hitchhiked home; got a ride. The guy didn't kick me out or even say anything until I told him what had happened. He said he was glad it wasn't he. I guess he had worried about that and was relieved to know. There's a suite of mercaptans that come out of paper mills that I find intolerable; particularly if the trees are pines. It feels like an allergy or chemical sensitivity of some kind.

[Edited on 9-4-2008 by chemrox]

JohnWW - 9-4-2008 at 21:13

What about H2Se, CH3CH2SeH, and other selenomercaptans? I am sure that they would be even smellier than the corresponding sulfur compounds, and more poisonous.

Butyric acid? Do you mean the n-isomer? I wonder if substituted butyric acids, or the other isomers, could be even worse. And what about thiobutyric acid?

12AX7 - 9-4-2008 at 22:28

Supposedly, 3-methylbutylaldehyde smells like cheese, but I can't find much on it. The other day, a student in lab was messing with something quite cheesy. I think an intermediate was something like, umm 3-nitro-phthalazide might be possibly the right name, in any case I recall it was nitrophthalic acid condensed with hydrazine (which is then similar to the phthalimide I cooked up a few weeks ago).

Tim

caribou - 10-4-2008 at 09:50

Of several thiols I have known and loved (MeSH, EtSH, PrSH, AllSH, t-BuSH, PhCH2SH, PhCH2CH2SH, HOCH2CH2SH, HSCH2CH2SH, PhSH and 4-MeOPhSH), phenethyl mercaptan was by far the worst smelling one. After it got absorbed, say, by a piece of a polyethylene tubing, the stench may remain there for years.

YT2095 - 10-4-2008 at 10:06

Some organic amines are pretty repulsive, trimethylamine, cadaverine etc....

edited to add the Some bit, not all organic amines smell bad.

[Edited on 10-4-2008 by YT2095]

MagicJigPipe - 10-4-2008 at 11:35

I never found butyric acid to smell that bad. It's bad but the smell is so strong that it just starts to get an acetic acid type "feeling" to it. Like the horrible smell subsides and it it just smells "chemically".

I don't know what ethanethiol smells like so...

Niether for me... NO2 is the worst IMO.

UnintentionalChaos - 10-4-2008 at 12:45

Quote:

Originally posted by 12AX7
Supposedly, 3-methylbutylaldehyde smells like cheese, but I can't find much on it. The other day, a student in lab was messing with something quite cheesy. I think an intermediate was something like, umm 3-nitro-phthalazide might be possibly the right name, in any case I recall it was nitrophthalic acid condensed with hydrazine (which is then similar to the phthalimide I cooked up a few weeks ago).

Tim

He'd be making luminol unless I'm mistaken. You then reduce the nitro group to an amine and you're done. This is a synthesis I've been wanting to do.

H2S doesn't really bother me, even though I'm aware of its potency...Neither does ammonia. I've never had a jar of butyric acid in front of me, but I have waded through ginko fruit for the edible nuts contained in them. The fruit have lot of butyric and caproic acid and rather enjoyed the smell. I relate it to cheese, not vomit. My roomate was going to throw up standing 10 feet away...

[Edited on 4-10-08 by UnintentionalChaos]

ScienceGeek - 10-4-2008 at 12:52

Quote:

Originally posted by MagicJigPipe

Niether for me... NO2 is the worst IMO.

This may sound strange to a lot of people, but I find the smell of NO2 kind of sweet...

Saerynide - 10-4-2008 at 16:43

Quote:

Originally posted by UnintentionalChaos
I've never had a jar of butyric acid in front of me, but I have waded through ginko fruit for the edible nuts contained in them. The fruit have lot of butyric and caproic acid and rather enjoyed the smell. I relate it to cheese, not vomit. My roomate was going to throw up standing 10 feet away...

Omg. I find gingko nuts REVOLTING. The street next to me is lined with gingko trees and it always smells like vomit. If I want to eat gingko nuts, I just buy them pre-packaged and smell-free at the store

Br2 is disgusting too. It smells like rotting sewage mixed with metal and chlorine (*barf*). I nearly threw up when I caught a whiff of an unexpected cloud

[Edited on 4/11/2008 by Saerynide]

crazyboy - 10-4-2008 at 17:15

Quote:

This may sound strange to a lot of people, but I find the smell of NO2 kind of sweet...

I certainly don't find it sweet but I kind of like the smell in low concentrations...

I hate sulfur dioxide when inhaled but like the aroma I also hate chlorine. Like the smell of dextrin, xylene, mononitroxylene acetone etc and "metallic odors"

Mononitroxylene smells so good I want to drink a whole bottle of it I tasted it once it tastes minty with a twinge of alcohol and something else (spicy?)

[Edited on 10-4-2008 by crazyboy]

sparkgap - 11-4-2008 at 00:05

Vitus says:

Quote:

Originally posted by Vitus_Verdegast
I have it on good authority that 1,3,5-tris(isopropyl)hexahydro-1,3,5-triazine, the condensation product of formaldehyde and isopropylamine, smells exactly like human semen.

I can easily imagine the possibilities of a combination of an aqueous suspension of the former, some microcrystalline cellulose, a 10 liter bucket and a certain local embassy building..

I've got paraformaldehyde; all I'll need now is the amine...

sparky (^_^)

DNA - 11-4-2008 at 04:48

Quote:

25.0 ml (294 mmol) of isopropylamine was dissolved in 75 ml of toluene. 28.6 g (352 mmol) of 37percent aqueous formaldehyde solution was added thereto under ice-cooling. After stirring at room temperature for 20 hrs, the reaction solution was washed twice with 125 ml of water. The solution was dried over anhydrous magnesium sulfate, and concentrated under reduce pressure to give 18.87 g. (88.43 mmol) of. 1,3,5-triisopropylhexahydro-1,3,5-triazine as colorless liquid.

This seems like a bad yield.
I also found another article with a 66% yield.
This is the one below

Quote:

General Procedure of 1,3,5-tris-alkylhexahydrotriazine synthesis. The tris-alkyltriazines were prepared by
treatment of the alkylamines with 37% aqueous solution of formaldehyde in a I:1.3 ratio, by 12 h at 0°C 3. The
mixture reaction was extracted with CHzCI2 and the organic layer was separated, dried over NaOH, and
concentrated under vacuum. ( 1:1 ).

DrP - 11-4-2008 at 07:01

I was working with some pentanol once. I thought it would be fine but it stank a bit like sick (a bit like butanoic acid).. Could it have oxidised in part to pentanoic acid? Would this have made that customary sickly smell?

I also hate pyridine!

[Edited on by DrP]

MagicJigPipe - 11-4-2008 at 12:50

"Could it have oxidised in part to pentanoic acid?"

Most certainly. It's supposed to smell like dirty socks. Gross!

vulture - 11-4-2008 at 12:54

Kumada couplings with thiophenes produce some kind of black, nearly insoluble goo which has an absolutely repulsive smell. It'll persist for days on end and must be destroyed with bleach or permanganate.

woelen - 11-4-2008 at 13:21

I just received some pyridine, which I ordered a week ago. It has a bad smell, but it is not as outrageous as some people describe. There are many other things, which I find more repulsive.

Strangely, the smell of Cl2, Br2, NH3, SO2, NOCl and NO2 is not bad to me, as long as they are not pungent. Some people say that Br2 has a horrible smell. To me, this smell is neutral (but very distinct and I can smell it exceptionally well). Strangely, almost all simple inorganic compounds which are very smelly, I do not really dislike. I think, the worst of the simple inorganic common smells is H2S, but even that is not so bad to me, that it makes me feel sick.

The smells, which I really dislike are CS2 (after some time, when it is exposed to air and humidity for some time) and some organic compounds (e.g. acetone, to which sulphur and NaOH is added). The smell of aniline, mixed with CHCl3 and NaOH also is very repulsive.

One compound, which makes me upset very much is HN3 (fast heartbeat, feeling of fear). Unfortunately, I cannot smell HCN and that is very dangerous. So, I do not do experiments with cyanides, or with reactions, where cyanides could be formed, at least not in more than 10's of mg quantities.

JeanGeilland - 12-4-2008 at 10:48

Referring to the stench of mercaptans from paper processing, I don't know how many of the active ingredients were mercaptans, but when we drove past a paper mill in Sweden years ago, the stench shook even an old lab-hound like myself. Our sons were small at the time and burst into tears in sheer rage at the asault. I assume it used the sulphite process in use, but certainly the smell suggested mercaptans rather than oxidised sulphur.

For my money mercaptans are not too bad, in that one quickly adapts to them. I made some in my student days (extra-curricularly) and was left in doubt whether they were bad at all. I made a few kinds, mainly butyl and allyl, to see which smelt worst, and the butyl smelt not much worse than scorched rubber, so I asked a woman to comment on the smell of an empty test tube in which I had had a few drops. She practically did a back somersault and later told me that she could not get the smell out of her nostrils till she woke up next day. Honestly, I had had no such intention!

Anyway, methane thiol is a component of sea smell, so, between that and my experience with other thiols, I am mildly sceptical about the ethanethiol record. H2S is hardly worth consideration as a pong. One gets used to it in no time.

The reason for messing with butyl was that the received wisdom was that butyl mercaptan was skunk smell. However, I have learned since that this is not strictly correct. Skunk smell contains a cocktail of components, not all of them produced directly by the skunk. The rest are microbial metabolites, so that the results are not particularly constant. Thereby hangs another tale, but of more relevance to biologists than chemists.

Allyl mercaptan was worse, with a nasty garlicky smell, but that too I rapidly became used to, so much so that when I added a few drops of peroxide to see whether that would give me the dithioether, the smell of garlick nearly knocked me over, smelling worse than the mercaptan imo at the time.

Oh yes, these oily substances do have the habit of diffusing into rubber and the like, as Caribou mentioned. Some of my product impregnated a rubber bung. I had occasion to bore a hole through it about a year later, not having had anything to do with mercaptans in between, and when I extracted the cork bore, I was shocked at the stench!

Saerynide might like to reflect that the name Bromine comes from Greek for “stench”.

Apparently a particularly persistent smell is trichloroanisole. If I have this right (never played with it myself) there have been warnings published against preparing the substance, since one cannot get the smell out of the lab for months. Skatole and related indole derivaties also are particularly offensive, smelling of ordure, and some of them are persistent.. Any students reading this, be warned! It would be a good way of ruining your career, not only as a student, to cause a snafu with such materials.

Some smells are less intense than others, but more revolting in higher concentrations: organic isocyanides are one example. Pyridine is another.

Use your good sense and never play around with such materials in more than semi-micro quantities!

Cheers,

JG

garage chemist - 13-4-2008 at 00:27

The triazine referred to above is an intermediate in the synthesis of N-methylisopropylamine from Rhodium:
http://www.erowid.org/archive/rhodium/chemistry/isopropylmet...

Jdurg - 13-4-2008 at 19:13

I kind of agree with woelen that the inorganic compounds don't really have too nasty of a smell to me. They smell bad, but they smell "I'm going to throw up" bad. It's the organic ones that really get me. Amyl Alcohol, Methyl Mercaptan, and putrecine are three that literally make me sick.

Nitroglycerin is kind of nasty to me only because of the massive headache I know I'll have after getting a whiff of it. So it's more of an association stench than an actual stench.

DNA - 14-4-2008 at 04:08

Lately I smelled benzylmercaptan or better known as the above mentioned phenylethylmercaptan...
It made me throw up and dizzy and the stench is still around my backpack for a couple of days.
If you open the bottle everything starts to smell like it, even if it is just lying around in the fumehood.
I had to throw away some pencils since they also smelled after I opened the bottle in the fumehood.

Nicodem - 14-4-2008 at 04:36

Quote:

Originally posted by DNA
Lately I smelled benzylmercaptan or better known as the above mentioned phenylethylmercaptan...

Benzyl mercaptan (benzyl thiol) is not the same as phenylethyl mercaptan (phenylethyl thiol).
The first is PhCH2SH and the second either PhCH(SH)CH3 or PhCH2CH2SH (depending on which of the two possible isomers you mean).
In my experience, benzyl thiol is quite bearable in small enough concentrations. Its stench reminded me of how elephants and their shit smell. However, I never had to deal with it in more than trace amounts that escaped from the fume hood. Yet I find it less terrible than PhSH, for example.

Sandmeyer - 14-4-2008 at 07:02

Glassware can be cleaned up with bleach, it effectively oxidise the thio compounds and thus removes stench. P4S10 used to make Lawesson's reagent also stinks like hell.

Armistice19 - 14-4-2008 at 09:50

The most absolutely horrifying, traumatic, dehumanizing, and unbearably excruciating smell that has ever wafted over the winds of this earth and into the noses of the inhabitants of this planet is beyond any shadow of a doubt a chemical called... Putrescine NH2(CH2)4NH2... the cousin of, and direct product of such a terrifying biological process that even the most honorable men and women of our country’s medical society would tremble at the thought of... BACTERIAL VAGINOSIS.

Pulverulescent - 15-4-2008 at 09:21

Hyperventilating, hysterical hyperbole aside, it aint called putrescine for nothing.

But the experience of smell can be modified by context or setting.

Obviously if you're planning a night of passion with your lady you don't want to walk into a room where the plug (urea/formaldehyde resin) of an appliance is overheating with decomposition.

And the Regal Roquefort has a butyric acid smell but the fact that it's a cheese mediates its strong odour.

Some months ago I had a situation where I needed to siphon, by mouth, a saturated NH4N03 solution containing various dead insects; millipedes, mostly.
I figured that, since I wouldn't actually ingest the stuff, I could rinse my mouth out later without worrying.

Anyway, it tasted terrible, with a very strong saltiness and something really nasty in the background.

Several mouth washes got rid of the saltiness but accomplished nothing else; along with an all pervasive bad taste in my mouth I had a similar stink in my nostrils.

That taste and smell stayed with me for an entire week!
It was so strong I couldn't smell or taste anything else.
It was one helluva long week!

P

chemoleo - 15-4-2008 at 19:12

Ethanedithiol.

No doubt about it.

The smell is so strong that just the container formerly containing a container of ethanedithiol reaked out the lab such that within 20 sec the room was vacated, after which the staircase and adjacent labs were also vacated.... (the empty container happened to be placed outside as an emergency measure, about 5 m away (with a wall inbetween) from the air con inlet, and it sucked in all the lovely smell, distributing it across the labs and 4 floors)... not a pleasant episode! Kept my head low for a while...

JohnWW - 16-4-2008 at 15:41

Quote:

Originally posted by chemoleo
Ethanedithiol.No doubt about it.
The smell is so strong that just the container formerly containing a container of ethanedithiol reaked out the lab such that within 20 sec the room was vacated, after which the staircase and adjacent labs were also vacated.... (the empty container happened to be placed outside as an emergency measure, about 5 m away (with a wall inbetween) from the air con inlet, and it sucked in all the lovely smell, distributing it across the labs and 4 floors)... not a pleasant episode! Kept my head low for a while...

That is very much the same what happened in my Chemistry Department at Victoria University of Wellington, New Zealand, back in 1969! The wax seal on the screw-top of a bottle of HS-CH2-CH2-SH in a chemicals storage room in the basement somehow became broken or cracked, and the garlicky odor of its vapor permeated the whole basement, until its source was discovered..

JeanGeilland - 18-4-2008 at 08:14

The most embarrassing aspect of my experimenting with thiols was the fact that they diffused through and round everything except solid glass or metal. No stopper was too tight and no organic material too insoluble to prevent its passage. And the merest trace was enough to tell everyone in the neighbourhood that something was horribly wrong.

Oh well, it's all experience, as long as you can store the information for unpredictable benefits later in life. What, after all, is science for otherwise?

JG

kilowatt - 18-4-2008 at 15:23

I have a friend that works at the local apiary, and would often come home smelling like butyric acid. They use butyric anhydride as a bee repellent. I find that smell utterly nauseating. I work across the street from the place during the summer too and you can often smell it.

Fyndium - 27-5-2021 at 14:16

I have had my fair share of smell issues, and I have found out that anything other than glass or metal is usually just easier to dispose than salvage. Especially plastics seem to take up some smells so badly that no amount of percarbonate or bleach washing gets rid of it. And yes, smells readily permeate through plastic, so even multiple ziplocs do little to stop the bigger odor demons.

The workspace is a bigger issue. A fume hood should be made 100% of stainless steel and glass to allow for efficient cleaning after odors. Possibly ozonizing the whole compartment after rinsing with percarb and bleach would get rid of the most. Apart from that, any porous materials and fabrics should be removed before working, and an apparel that can be effectively washed or at worst case disposed should be worn.

DraconicAcid - 27-5-2021 at 15:01

Butyric acid is mild compared to isovaleric.

Texium - 27-5-2021 at 18:57

Someone at work has been running a lot of Swern oxidations lately. Normally everything stays in the hood, so you’ll only catch the occasional whiff of sulfur/rotten-broccoli-like odor, but recently he opened one of his waste containers, which contained a lot of dimethyl sulfide, outside of the hood. It was open for no more than 30 seconds, but the odor in that region of the lab was nostril-burningly bad for the rest of the day.

BromicAcid - 28-5-2021 at 17:04

Ethyl isonitrile all day and then some.

Bedlasky - 28-5-2021 at 17:52

From what I read, thioacetone and carbon diselenide are quite nasty.

https://en.wikipedia.org/wiki/Thioacetone

https://en.wikipedia.org/wiki/Carbon_diselenide

Worst things I've ever smelled are probably tert-butylamine and N,N-dimethylisopropylamine. They smell like ammonia, but much more distinctively.

Fyndium - 28-5-2021 at 21:22

What is actually the mechanism of extremely smelly chemicals? For example, acetone and sulfur alone are not that smelly or unpleasant at all, at least in moderate concentrations. Sulfur, of course, is not volatile in elemental form, but when burnt, does not smell that bad still. What do they react with in our olfactory receptors, and what makes us consider them so stinky?

Does thioacetone have any commercial uses at all?

[Edited on 29-5-2021 by Fyndium]

Fery - 28-5-2021 at 23:18

Recently I received a parcel by PPL courier and they behaved very rude to the parcel because 500 ml bottle with 33% diethylamine was broken. The bottle itself was protected with a lot of layers of filter paper and bubble foil so only little of chemical escaped, but the leakage was visible on the bottom of the cardboard box. Also the cardboard box was protected by few layers of transparent adhesive tape (and big sign that it contains glass, should be handled with big care, should be transported always in upright position, never turned bottom up etc). Strange that there were more chemicals but they broke only the most nasty compound which was best protected. The courier unloaded the parcel in a big hurry :-D and disappeared as quickly as possible with widely opened all car windows although it was quite cold and rainy outside. Luckily it was rainy day so I put the broken bottle into a bucket of water and diluted that scent quickly. I had to order another bottle and the second time they delivered it unbroken (2 days ago). It was not expensive, it was an old sample and its cost was only 100 CZK = 4 EUR.
Also dissolving NH3 gas in ethanol was quite brutal after the alcohol got saturated (during dissolution which is exothermic process it became slightly warmer which decreased the solubility of ammonia gas in the alcohol), I did it outside during winter night when I expected all my neighbors be inside their houses.
I have valeric, butyric, isobutyric, isovaleric, caproic acids. Sniffing them from opened bottle was not pleasant but such high concentration very likely atenuated my smell receptors. Sniffing them in very low concentration (empty plastic bottles after I transferred the content into glass bottles) was much more unpleasant.
2 preparations of allyl alcohol (glycerin + formic acid) were not nice and they both had always almost 1 day consequences (tears in eyes, irritated nose and throat). Maybe it was caused not only by the allyl alcohol itself but also acrolein?
I had not yet experience with thiols (with exception of mercaptans used in natural gas and propane-butane), I need to improve my skills before I try them.

karlos³ - 29-5-2021 at 06:42

Quote: Originally posted by Texium

Someone at work has been running a lot of Swern oxidations lately. Normally everything stays in the hood, so you’ll only catch the occasional whiff of sulfur/rotten-broccoli-like odor, but recently he opened one of his waste containers, which contained a lot of dimethyl sulfide, outside of the hood. It was open for no more than 30 seconds, but the odor in that region of the lab was nostril-burningly bad for the rest of the day.

I made savoy cabbage like two weeks ago and I couldn't eat much of it and had to throw it all away the next day, when the dimethylsulfide stench somehow became more noticeable.
I think I can't eat that anymore, because I dislike dimethyl sulfides smell so much, just like with brussels sprouts.

I still remember that one time I ran an albright-goldmann oxidation, luckily at very small scale, and was a bit surprised by the overwhelmingly strong stench when opening the flask, horrible stuff.

Dr.Bob - 30-5-2021 at 07:11

Quote: Originally posted by BromicAcid

Ethyl isonitrile all day and then some.

I have not made that one, but several others, and the smell is unfamiliar, but so horrible as to be hard to imagine. It just makes you want to vomit. The funny thing is that most are not toxic, as they hydrolyze in vivo quickly. They just smell like death itself.

DraconicAcid - 30-5-2021 at 08:23

I remember having to scream at a grad student to get the bottle of phenyl isothiocyanate in the fume hood when it's open, and he just kind of blankly stared at me, asking, "Then how am I supposed to weigh it out?"

Fyndium - 30-5-2021 at 23:13

Isopropylamine is much less stinky what I thought.

Raid - 30-1-2023 at 11:31

One of the worst things i have smelled is concentrated hydrazine.
It smells like highly concentrated ammonia, you can smell it from 5 feet away.

Sulfur Based

MadHatter - 30-1-2023 at 12:21

Just about anything combined with sulfur tops the category for me and especially
hydrogen sulfide. All mercaptans fill the bill as well.

[Edited on 2023/1/30 by MadHatter]

chloric1 - 31-1-2023 at 05:52

Worst stench is when I consume dairy milk. Ugh! My stomach!

SnailsAttack - 3-2-2023 at 22:58

Last summer I was doing a lot of experiments involving chemical extraction from plants. Had zero success, and the smell was ungodly, even using bleach to negate most of the sulphides.

Pro-tip for plant extractions: do NOT cook the plant material. It frees up all sorts of nasty-smelling organics, not to mention nutrients that feed molds.

BromicAcid - 3-2-2023 at 23:15

I had the (dis)pleasure of being involved in the manufacture of a whole series of isonitriles, ethyl, propyl, butyl. They are truly noxious. However, there is only one time I vomited from a smell - though it was not a specific chemical.

When I used to work at a trailer park we were responsible for the water supply to each trailer until it connected to the trailer. The water line would come out of the ground about 8 ft below ground level and rise up through the center of a 2 ft diameter pipe in the ground till it connected to the trailer. We got a call that someone had a leak on the water supply.

Sure enough we arrived at the trailer and there was a leak somewhere in the crock in the ground. It was filled with some (a foot or two) of water. We tossed a submersible pump down the hole and let it go to work. Unknown to us, a skunk had fallen into that crock and died. In the ensuing weeks/months it had rotted to the point that the flesh and muscles were easily masticated by the pumping action. Within short order this skunk stew started to be discharged by the pump into the area where we were standing. It was... too much. Dry heaves and vomiting all around and from the smell alone.

I also had to optimize a synthesis for HMDS (Bis(trimethylsilyl)sulfide) once upon a time. The compound while not the worst smelling in the world is still pretty horrible but the claim to fame is the odor threshold. A single drop in a well ventilated chemical production bay was able to be smelled outside the building.

[Edited on 2/4/2023 by BromicAcid]

phlogiston - 4-2-2023 at 04:03

One class of compounds I haven't seen mentioned yet are alkynes.

In organic synthesis classes we've had to synthesise a number of small alkynes and all of them were really awfull, with a very low smelling threshold. Couldn't wash the smell of your hands or out of your clothes very well.

DraconicAcid - 4-2-2023 at 09:45

Quote: Originally posted by phlogiston

One class of compounds I haven't seen mentioned yet are alkynes.

In organic synthesis classes we've had to synthesise a number of small alkynes and all of them were really awfull, with a very low smelling threshold. Couldn't wash the smell of your hands or out of your clothes very well.

I remember the smell of phenylacetylene, but it's fresh-baked bread compared to phosphines.

Metacelsus - 5-2-2023 at 09:20

In undergrad I made quite a few batches of 3,5-dithiahepta-1,6-diyne. Basically https://en.wikipedia.org/wiki/2,4-Dithiapentane but with ethynyl groups on the ends instead of methyl. It made the whole lab smell like weird truffles. Years later I still don't like truffles very much.

I agree that phenylacetylene isn't bothersome.

[Edited on 2023-2-5 by Metacelsus]

CRUSTY - 14-2-2023 at 07:49

It's not the worst of the worst but after prolonged exposure to cumene (2-phenylpropane) I think it's one of my least favorite odors. During the pandemic even small amounts would persist in my disposable masks and I would smell it all day. Makes me nauseous just thinking about it.

andyloris - 14-2-2023 at 09:18

I think the worst smelling chemical I ever smelled is the product of heating of MSG on aluminum foil.
It smells like things that were in a closed space for long, except it's much more pungent and also reminiscent of tobacco smoke.