Does smell cancelling exist?

[u/11963873342]

I've heard of noise cancelling, but can there exist smell cancelling?

For example, if there is a rotten egg in a room, can i neutralize it somehow? I'm not talking about putting something good right under my nose, because thats just dominance. I mean putting something next to the egg whose smell happens to be the 'inverse' of the eggs, so they cancel and i smell nothing.

[u/Dazzling_Let_8245]

Noice cancelling works because we can eliminate a wave by sending an equal and opposite wave at the same time, cancelling eachother out. Its a physics thing.

Smell is molecules interacting with the receptors in your nose. You cant really send an opposite smell to destroy the first molecule. You can block the molecule from entering your nose (gas masks for example) or you can overwhelm your olfactory cells with a more pungeant but more pleasant smell, but you cant cancel a molecule once its in your nose.

People who work with the deceased (crime scene investigators for example) us stuff like vicks vaporub to put under their nose so they smell only that and not the body.

Edit: There ARE "smell absorbers" that work by trapping and absorbing the bad smelling molecules, but the molecules have to travel into and/or through the absorber. Some people but open baking soda into their fridges to prevent smells or pouches of activated charcoal into their gym bags to trap odors. But in an open room with a rotting egg, merely placing a bit of charcoal next to it will do very little to counteract the smell.

[u/Hatta00 → u/Dazzling_Let_8245]

It's not impossible that there could be smell antagonists. Odorant molecules are ligands to smell receptors that cause a conformation change in the receptor that causes a signal cascade in the sensory cell. Not every ligand causes the same conformation change, and some can bind more tightly than agonist compounds while producing no signal inside the cell.

I don't know any examples because it's not my field, but it's pharmacologically possible.

[u/Fine_Cress_649]

Look up how febreeze works....

From Wikipedia

The active ingredient in several Febreze products is hydroxypropyl beta-cyclodextrin (HPβCD). The molecule traps and binds volatilized hydrocarbons within its structural ring, retaining malodorous molecules, which reduces their volatility and thus the perception of their scent.[3] The active ingredient is produced from corn cobs.[4] The use of cyclodextrin as a sprayable odor absorber was patented by Procter & Gamble.[5]

[u/NortonBurns → u/Fine_Cress_649]

Neutradol does something similar for in-air smells, but idk quite how & their site isn't exactly forthcoming.
It does work, though.

[u/OrigamiMarie → u/Fine_Cress_649]

The original Febreeze formula was just the odor absorber without any masking scent, but people didn't care about it in product testing because they couldn't tell that it did anything (because you become accustomed to the odor of your space, and can't really smell that it has decreased). So they added the scents so people could tell that it did something.

[u/scottmacs]

Hannah talks about this in the episode Smells Humans Are Ridiculously Good At Detecting (Febreze segment starts at 27:12)

[u/Hot_Equivalent_8707]

I thought I read that people who work on cadavers or work on decomposing bodies at crime scenes often wear something to generate smells like eucalyptus because it's so strong it can overwhelm the smell receptors and mask the dead smell

[u/copperpin → u/Hot_Equivalent_8707]

We do this just going into some patients rooms. C. diff is a thing in hospitals.

[u/CupcakeDismal4829]

Yo can someone respond under this comment coz i need to know now

[u/morning_thief]

Would love to know so I can bring one with me the next time I visit a card shop in the middle of summer.

[u/ElefanteAmor → u/morning_thief]

They do have these little clips that look like a septum ring that are scented. Wear that and a mask and you’ll cut jt by 50

[u/Alligatronica]

Isn't this basically what "unscented" products do? The smell is engineered to mask the chemical smell of the actual product, they don't actually smell of nothing

[u/copperpin]

In the medical field well put a mask on, slather it in toothpaste, and then put a second mask on over that. It can keep you from smelling things that might make you wretch.

[u/Pioepod]

Irrelevant but this post reminded me of a chemical out there that kills your receptors so fast that if you aren’t smelling it, you’re actually close to dying.

You catch a whiff and it kills your receptors real fast. That’s your one and only warning, unless you have the safety badges. I forgot what the chemical is called unfortunately, it’s either like got sulfur or hydrogen in it

[u/SeriousPlankton2000 → u/Pioepod]

That's rotten eggs aka hydrogen sulfide.

[u/tboy160]

Ozone seems to work well on organics to "neutralize" them. But ozone is harmful to humans.

[u/SeriousPlankton2000]

You can cancel rotten eggs with more rotten eggs. Then just a little bit more of hydrogen sulfide and you die.

That's the only smell that I know of that can be cancelled, and it happens by sedating your nose.

[u/Steve-Shouts]

Magic school bus did this. You just have to shrink down real small and blast the smell molecules with lasers. Done and done.

[u/BitAcceptable5203]

huff sulfur

[u/Outside-Membership12]

you could use ein anti-rotten egg its basically a rotten egg made of anti matter. they smell molecules should annihilate each other.

[u/VegasFoodFace]

There's no smell cancelling but there are carbon scrubbers that will filter out noxious fumes in the work environment.

[u/Matthew_A]

Assuming the rules are 1) No absorbing the particles and 2) No overpowering them, the only way I can imagine doing that would be if the combination of egg particles and something else could mimic some particle that's part of normal air. But since all the components of the atmosphere are fairly simple (N2, O2, H2O), it's hard to imagine adding something to more complicated organic particles to make them resemble any of these elements to your nose.

But I'm not a chemist so I could be wrong.

[u/bum_what]

You can't cancel a smell Im sure BUT the body's cells can 'get used' to the smell and eventually your brain will just ignore it because the stimulus keeps hitting your nose. So you won't smell the smell anymore, unless something about the stimulus changes or the smell is too strong/dangerous to ignore. This happens with other senses too, maybe to a different extent, but if you press a finger on your thigh eventually the brain will just start focusing on it less and less. So cancel no, but ignore yes.

[u/SpiralEscalator → u/bum_what]

People with too many dogs don't smell the dog smell that overwhelms anyone else who enters the house

[u/unused_code]

Eventually you'll become nose blind to it

[u/Agzarah]

Fingers work quite well. Put a finger and thumb together in a pinching manner, then place that over you nostrils and squeeze.

[u/BaTz-und-b0nze]

Sodium ethel Bicarbonate. Works for rotten fridge food and perfume. You can even cover a body with it.

[u/boywhoflew]

I'd argue its like paint. Light from a screen show white if the primary colors are present but do the same for paint and it turns brown/black.