Wednesday, July 8, 2026

The Smell of Risk


Environmental Disparities and Olfactory Aesthetics
Hsuan L Hsu, NYU Press, 2020

Image credit: "Sweat" Peter De Cupere Olfactory Performance Art circa 2012

They definitely had me with that title, I'll admit. But after reading, I conclude it's just not my thing. I try to withhold my frustration with the author, the editor, the publisher, I don't know, whoever might be at fault when you're more than halfway through a book you really wanted to be really good but now you feel like you should go read a book on the science of deception instead because you've been duped.

This book is mostly about what I'll call racism, but through an olfactory lens. But I want something more. Or maybe just something else. Maybe it's me; maybe I'm the one without the PhD (I am), but sometimes I lose my patience for these circular ramblings, the circle-jerking, fart-huffing, pathological neologistic echo chamber of your own super sub-category of knowledge, where you've squeezed yourself so far into your niche that almost nobody else can criticize you because they have no idea what the f you're talking about. (The fact that you're making up half the words you use to describe said subject kind of works to that effect naturally.)

It's doubly ironic then, that here I am, a person who very accidentally, and non-academically, has a background in both olfaction and industrial hygiene, to read this work, otherwise insulated from criticism by sheer epistemological remoteness. My problem is that some of the material here is problematic from a public health point of view. There are arguments in this book that we should allow something like incense burning in the workplace because it's meaningful for certain people of certain cultures, and because it's not fair that colonizers took away the ability for us to express ourselves, to cope with our lives, and it's things like this that make racism and colonialism so bad. But again as a public health specialist, I have to clarify - are we saying that we should allow people to conduct relatively uncontrolled combustion activites indoors, with other people around, and in a workplace no less, which means some of those occupants are there not by choice but because they need to pay their bills, because some of these people miss being able to do that back where they come from? So I see less of a blurred line, a clear line in fact, pretty obvious, where things are "ok" vs "not ok". Exposing the public to partial combustion by-products indoors is not ok. I can't decide whether it's not racist NOT to do that, or to prohibit others from not doing that, so I have to leave that up to you, the public, and to academicians who use words that don't exist to reinforce their ideas.

All that being said, there are some interesting things in here: 
  • Smells that don't smell (the "scentlessness" of the South Pole that inspired a soap manufacturer) and smells used to deodorize (soap).
  • "Deodorization" is what seems to be the concurrent theme; could have been the title. 
  • Somewhat like myself, perhaps like so many people who became fascinated by smell, the author's interest begins after one night of sleeping in an apartment freshly painted. It messes up his sense of smell, a partial anosmia that lasts years, but brings so much attention to an otherwise invisible sense. 
  • Kant's Perfumed Handkerchief - Kant is infamous for his either vicious abhorrence or total ignorance of the sense of smell, but here he betrays a bit of his ... intolerance for others (then again is this just support for good manners; throughout the whole book this is a recurring thought in my head) ... "The man who pulls his perfumed handkerchief from his pocket treats all around to it whether they like it or not, and compels them, if they want to breathe at all, to be parties in the enjoyment. --Kant's Critique of Judgement
  • [By the way, 14 pages in and we're at footnote 51, just saying]
  • Sherlock Holmes often used smell in his investigations
  • The Merck manual calls hyperosmia psychosomatic [but it is? not sure the point here]
  • The American Southwest was in part settled by health-seeking migrants fleeing tuberculosis p52
  • For conservation purposes, museum air is standardized by UNESCO, ICOM the International Council of Museums and IIC the International Institute for the Conservation of Museum Objects, and see the book The Museum Environment by Butterworth 1978 p88-90
  • "Occularcentric" museum experience; "derecognition" of smell; "toposmia" is how a place enters our bodies through smell; "breathers" are participants in an olfactory art exhibit not like viewers or something passive like audience
  • He mentions plenty of good olfactory artists: Boris Raux, Anicka Yi, Peter de Cupere (p87), but let's focus here: Sean Raspet is an olfactory artist, and this is nuts - Micro-Encapsulated Surface Coating 2014 - he puts a Summa canister in a gallery for a week, analyzes the ingested olfactory profile, then recreates it using the same chemicals found there, and releases it back into the gallery via a scratch-n-sniff paint that he made and put on the walls, all the while a negative air machine sucks out the present odors of the gallery. ... Very, very cool. But I'm suspicious as to whether the output = the input. Like there are too many other variables besides the molecular components, the most significant of which is the simple fact that for smells, concentration can change a smell to something otherwise unrecognizable. For example, skatole, the smell of shit, is added to perfume, because at very small amounts, and when mixed with the right ensemble, it smells friggin great. But then there's air movement, diurnal changes in building performance, I mean the variables are kind of endless. The idea is just totally nuts, in a good way, but the actual results; I'm skeptical.
  • And here is an example of my problem with what I might try to call academia. Maybe it's got something to do with the humanities scholars, and not being required to think like an engineer or a scientist, or maybe even a lawyer. Like you will hear things being said as facts with no justification about how this or that causes this or that, but simply by the sheer fact that they came up with the association, and it sounds great as a series of words strung together, so it must be true? The author says, "[The exhibit] simulates hyperosmia, artificially enhancing visitors' olfactory sensitivity to the gallery air." (p101) But how does he know that's what happens? It's what the art tries to do, what it wants to do, but we don't know what it did to people unless we go and ask them, or at least monitor their behavior somewhat, and there's no mention of any of that. So again I would ask, how do you know it "enhances visitors' sensitivity"? What if they don't even notice? You want it to do that and the artist wants it to do that, but neither of you has any say, and apparently no supporting evidence. And for what it's worth, and for at least a few very different and mostly unrelated reasons, I don't think most people even notice, so I don't think it did "enhance" anything except your own perception of your own thoughts, because that seems to be what a lot of this is about. Then again, I am not the one with the PhD, granted. 
  • Now here's some cool insight; but I'm not sure it belongs to the author originally - Kate McLean's Smell Maps circa 2014 is cultural preference (ie racist) because she calls "dried fish" and "cabbage" as bad smells, but they come from Asian neighborhoods, and to Asians, they aren't bad. (I might have to argue, weakly, that rotten fish and rotten cabbage are like two of the most representative bad smells of all, and so, only with the addition of "rotten", the author's argument fails.) p113
  • Many of the references cited here are so tedious; they aren't books or articles but what seem to be random scraps of paper that make the citation style look like an alien language; I guess part of the point of doing esoteric research is to attempt to uncover some of this stuff that would otherwise be lost to history; but for much of this I'm left with the thought that maybe it should be lost. Also, I must be outdated because there seems to be a new way to do in-text citations, so that "Braiding Sweetgrass" looks like (BrS, 121) not (Braiding Sweetgrass, 121)
  • There is an Israeli firm Odortec that makes "skunk water" for crowd control, but it didn't work in India. p159
  • Paul Gauguin's memoir Noa Noa 1901 means "fragrant" in Tahitian
  • Smudging, or incense I suppose, he calls "air conditioning" and a way of decolonializing smells; and it's kind of the opposite of the use of mustard gas on uncooperative populations
  • "Atmospheric engineering and olfactory aesthetic interventions" p182
  • Certain cultures want to use incense for spiritual and communal purposes but they can't because of smoke detectors, and this is where I'm like hold on, we need to stop somewhere, and this would be a good place to stop. Smoke detectors as systematic and persistent instruments of oppression? You're not getting a lot of people on your side with that argument, not anyone who's loved one's have died in a fire, not anyone who's had to save people's lives from a fire, and not anyone who's job it is to be responsible for public safety with respect to fire. p185
  • Curators at the Museum of Natural History Department of Anthropology provided a space in the storage facility for Native American visitors who wish to smudge sacred objects in the collection (and interesting in light of the fact that much of these artifacts were historically dosed with insecticide, which continues to be a persistent source of occupational health hazard for museum workers) p185
  • At the Natural Museum of the American Indian (is this the Smithsonian in New York City?), the Human Remains Vault is smudged with a mixture of tobacco, sage, sweetgrass, and cedar every week. 
  • And ... certain museum practices like bagging, freezing, or low oxygen may be inappropriate for suffocating the living entity in the artifact.
  • The idea of fragrance-free workplaces (also racist) vs working next to a highway; so the idea of forcing people to be exposed to dangerous environmental conditions like traffic pollution, while also prohibiting them from wearing perfume, is messed up. I like it when people express themselves, even if it don't like it myself, because I support creative expression, and I like perfume, but I also understand the need for and desire of a healthy workplace, so I'm stuck on this one.  
  • The Yes Men Exxon Climate Victim Candles, omfg: They told 300 oilmen at Canada's largest oil conference that the real solution to climate change was to turn everyone who dies into fuel so that the all-important free market could continue to work well past doomsday. As volunteers passed out flesh-scented candles, a funeral tribute played for an Exxon janitor named Reggie Watts, who had graciously donated his body to be turned into candles as a test of the Vivoleum concept. (He was played by the actual Reggie Watts) ... good luck finding this video on your own, the United States government straight banned this permanently from the internet, well as best it could; you will absolutely not find this via a google search or on youtube. I can't even find it on the porn sites. The only place it's hosted is the Internet Archive: https://archive.org/details/The.Yes.Men.Fix.The.World.P2P.Edition.2010.Xvid
  • And Anicka Yi's use of a stink bomb during a high profile meeting of these executives to scare the absolute living shit out of the big money assholes who were responsible for Bhopal. ... they thought they themselves were now being poisoned. I don't care about their feelings, that is genius, and that is what art is for. 

Tuesday, April 22, 2025

This is a Test


An at-home smell test could pave the way for early detection of Alzheimer's disease
Mar 2025, phys.org

What's wrong with UPSIT or Sniffin' Sticks?

"Forced-choice measures", that's what; they don't allow enough measurement of the higher order executive functioning that's so hideously complex in its relation to the deep limbic system.

Recall Bloom's Taxonomy as a scale of cognitive effort, where memorization is the easiest, using the least amount of cognitive power, and then goes up through comprehension, application, analysis, synthesis, evaluation.

Their new test is called the AROMHA Brain Health Test (ABHT), and it's actually a bunch of tests combined:
  • Odor percept identification (OPID) test - participants smell an odor, answer a question, and then choose from four provided odor names (this sounds like the basic UPSIT, which is an odor identification test, and uses multiple choice instead of open-ended)
  • Percept of odor episodic memory (POEM) test - participants distinguish between new odors and those presented earlier (so this is a memory test)
  • Odor discrimination (OD) test - participants identify pairs of smells as either the same or different (also called a pairwise similarity test)
  • ***This is new*** a meta-cognition measure embedded in the odor percept identification tasks, where participants sample the odor and then choose an odor name from a forced choice list of 4 options, but are then asked to evaluate their confidence: “I Guessed,” “I Narrowed Down to Three,” “I Narrowed Down to Two,” or “I Am Certain.”

via Laboratory of Olfactory Neurotranslation at McCance Center for Brain Health, and Department of Neurology at Massachusetts General Hospital: Benoît Jobin et al, The AROMHA brain health test is a remote olfactory assessment to screen for cognitive impairment, Scientific Reports (2025). DOI: 10.1038/s41598-025-92826-8

Partially unrelated image credit: AdobStockWassertest - Fraunhofer IGB - 2025

Monday, April 7, 2025

Body Odor Perceptronics


We have a winner - this article has a year's worth of stuff to look into. 

An aromatic lexicon: Comprehensive fragrance database offers insights into human perception of odors
Feb 2025, phys.org

University of Jena and Technical University of Dresden's Olfactorial Perceptronics Fundamental Odor Database - The project brings together various research disciplines: psychology, physics, chemistry, materials science, and medicine. For the database, they had more than 1,200 test subjects smell 74 monomolecular odor samples, then describe what they perceived with their nose in their own words and also used a rating scale to assess, among other things, how pleasant or intense they found the respective odor. 
Public-access app (German language only) https://crown-dataset.streamlit.app/

University of Jena and colleagues from Finland, Israel and the Czech Republic Smart Electronic Olfaction for Body Odor Diagnostics or SMELLODI - The researchers asked 2,600 test subjects in 17 countries how they would describe the odor of individual parts of the body and how it differs when a person is ill or has been exercising. This resulted in a catalogue of descriptions for various odors in 13 languages, which produces clear overlaps and thus allows general statements to be made about how certain areas of the body smell. The test subjects perceived armpit odor as sweaty, sour and stinky, they described bad breath as either fresh or stinky and foot odor as cheesy.


Here's a sample of the Standardized Lexicon of Body Odor Words, in English:
  • "healthy" - fresh, clean, neutral, sweet, natural
  • "after exercise" - sweaty, strong, salty, sour, musky, ... wet,
  • "from the mouth" - food, rotten, minty, sour, foul, gross, garlicky, fresh, strong, 
  • "from the feet" - sweaty, sour, cheesy, stinky, pungent, strong, dirty, smelly, bad
  • "from the female genitals" - fishy, sour, sweet, musky, ... metallic, ... salty, 
  • "from the male genitals" - sweaty, musky, salty, musty, sour, cheesy, stale, urine, ... fishy, 
  • "stressed" - sweaty, sour, strong, pungent, stinky, sharp, salty, 
  • "from the armpit" - sweaty, strong, sour, musky, salty, sweet, ...

via University of Jena and TU Dresden: Antonie Louise Bierling et al, A dataset of laymen olfactory perception for 74 mono-molecular odors, Scientific Data (2025). DOI: 10.1038/s41597-025-04644-2

Also: Antonie L. Bierling et al, A standardized lexicon of body odor words crafted from 17 countries, Scientific Data (2025). DOI: 10.1038/s41597-025-04630-8


Friday, April 4, 2025

Ontogenetics and Olfaction


To help AIs understand the world, researchers put them in a robot
Feb 2025, Ars Technica

“The inspiration for our model came from developmental psychology. We tried to emulate how infants learn and develop language”

Researchers also tried teaching an AI using a video feed from a GoPro strapped to a human baby. The problem is babies do way more than just associate items with words when they learn. They touch everything - grasp things, manipulate them, throw stuff around, and this way, they learn to think and plan their actions in language. An abstract AI model couldn’t do any of that, so Vijayaraghavan’s team gave one an embodied experience - their AI was trained in an actual robot that could interact with the world.

(The writeup for this article by Jacek Krywko for Ars Technica is very good.)

This is the idea, but instead of just an RGB camera, we need proprioception and the emotions that go along with it, and we'll have artificial smelling entities. 

via Okinawa Institute of Science and Technology: Science Robotics, 2025. DOI: 10.1126/scirobotics.adp0751


Wednesday, March 26, 2025

The Artificial Economy

 

On Sep 9 2024, I do a quick search on myself, and find my book being sold in Walmart. I don't sell the book at Walmart, only Lulu who is the printer-publisher. I even very specifically decided not to use Amazon services, or sell it at Amazon, or anywhere else besides Lulu, and for reasons that I have, some of the same reasons you might have if you were to do the same thing. Maybe you know the reasons, maybe not. Yet here it is, being sold by someone who technically wasn't authorized to sell it, at a price that I did not set, and also somewhere in Taiwan (although in my mind the entire website is artificially generated so it doesn't know where it is). 

Hidden Scents: The Language of Smell in the Age of Approximation (Paperback) $12.46

At least they do list the publisher as Lulu Press.

Note that on Lulu, the book is for sale for $14.98. So Walmart is losing money just to get the purchase, something called "loss leading" in the artificial economy in which we live. 

博客來-Hidden Scents: The Language of Smell in the Age of Approximation

The point here is that we live in an artificial economy, where ownership doesn't matter, authorship doesn't matter, licensing doesn't matter, and even money doesn't matter (until you need it to buy food, of course).


Thursday, February 20, 2025

Smelling the Screen Door

 

If you stand close enough to a screen door to touch your nose to the screen, it smells like the street when it first rains; but it has to be an old screen, not a new one. (discovered Mar 1 2024; although I've known this smell my whole life as "the screen door" I never noticed it was the same smell)

I find a reddit post titled "I can smell this screen door," and someone comments "Rainwater, rust and just a hint of bug guts"

Tuesday, February 18, 2025

Odor Identification vs Odor Perception

 


Scientists reveal chemical structural analysis in neural computations that allow us to identify odors
Mar 2024, phys.org

via Institute of Psychology of the Chinese Academy of Sciences: Yuting Ye et al, Decomposition of an odorant in olfactory perception and neural representation, Nature Human Behaviour (2024). DOI: 10.1038/s41562-024-01849-0



Name that odor: Identical odors seem different when given different names
May 2024, phys.org

Participants were given minty and citrusy odors to sniff, which had been labeled with two words; for example, mint-menthol or eucalyptus-menthol. While sniffing, participants were scanned using an ultrahigh-field (7-tesla) functional MRI (fMRI) machine. While MRIs take snapshots of the brain, fMRIs enable researchers to see activity in the brain over time, in this case where in the brain the information about the labeled odors was being processed.

After the scan, participants sniffed the odors again, but this time presented in pairs, and then rated how similar or different they thought the odors were from each other. In this second round, the odors and their labels were either the same, or two identical odors were given different labels, or different odors were given the same name.

"We were surprised to discover the clear effects of labels on the participants' ratings of odors. We could also see from the fMRI results how the semantic context, the word labels used, influenced odor-coding activity in the piriform cortex, a key part of the primary olfactory cortex for processing smell."

Results showed that participants reported a greater difference between odors when two identical odors were given different names, than when they were labeled the same. The fMRI data showed that some parts of the piriform cortex were affected by the words used to label the odors, while other areas were more affected by the odor itself.

The researchers suggest that this may be because areas affected by words would differ from those affected by odors within the primary olfactory cortex, but further research is needed to confirm this. The team also noticed a significant connection between the areas within the piriform cortex affected by words and other regions of the brain involved in language processing.

via University of Tokyo: Toshiki Okumura et al, Semantic context‐dependent neural representations of odors in the human piriform cortex revealed by 7T MRI, Human Brain Mapping (2024). DOI: 10.1002/hbm.26681


Detecting odors on the edge: Researchers decipher how insects smell more with less
May 2024, phys.org

Wiring diagram of the fly nose; and since olfaction is the ideal model for how the brain works, because of its severe simplicity - 

Previous investigations of the odor processing system in flies focused on the central brain as the main hub for processing odor signals. But the new study shows that the effectiveness of the insect's sensory capabilities relies on a "pre-processing" stage in the periphery of their sensory system, which prepares the odor signals for computations that occur later in the central brain region.

Flies smell through their antennae, which are replete with sensory hairs that detect elements of the environment around them. Each sensory hair usually features two olfactory receptor neurons. "The signals carried by the wires interfere with each other through electromagnetic interactions," and helps flies quickly compute the "gist" of the odor's meaning.

"Remarkably, our work shows that the optimal odor blend—the precise ratio to which each sensory hair is most sensitive—is defined by the genetically predetermined size difference between the coupled olfactory neurons," said Aljadeff, a faculty member in the School of Biological Sciences. "Our work highlights the far-reaching algorithmic role of the sensory periphery for the processing of both innately meaningful and learned odors in the central brain."

via University of California San Diego: Palka Puri et al, Peripheral preprocessing in Drosophila facilitates odor classification, Proceedings of the National Academy of Sciences (2024). DOI: 10.1073/pnas.2316799121


Another step towards decoding smell: Investigating the neuronal mechanisms of human odor perception
Oct 2024, phys.org

Yes, thank you once again, epilepsy: 

The research group has now succeeded for the first time in recording the activity of individual nerve cells during smelling, by monitoring epilepsy patients.

While the activity of nerve cells in the olfactory cortex most accurately predicted which scent was smelled, neuronal activity in the hippocampus was able to predict whether scents were correctly identified. Only nerve cells in the amygdala, a region involved in emotional processing, reacted differently depending on whether a scent was perceived as pleasant or unpleasant.

In a next step, the researchers investigated the connection between the perception of scents and images. To do this, they presented the participants in the Bonn study with the matching images for each odor, for example, the scent and later a photo of a banana, and examined the reaction of the neurons. Surprisingly, nerve cells in the primary olfactory cortex responded not only to scents, but also to images.

via Department of Epileptology at University Hospital of Bonn: Marcel S. Kehl et al, Single-neuron representations of odours in the human brain, Nature (2024). DOI: 10.1038/s41586-024-08016-5


Humans can distinguish odors with millisecond precision
Oct 2024, phys.org

Human olfactory perception can detect fine chemical changes within the duration of a single sniff.

A unique sniff-triggered device that controls odor delivery with a precision of 18 milliseconds created temporal odor mixtures, presenting two odors one after the other, tested with 229 participants across five experiments to see if they could distinguish these mixtures. 

When two odor compounds, A and B, were presented in different orders, participants could tell the difference when the delay between the compounds was just 60 milliseconds.

via Institute of Psychology of the Chinese Academy of Sciences: Wen Zhou, Human olfactory perception embeds fine temporal resolution within a single sniff, Nature Human Behaviour (2024). DOI: 10.1038/s41562-024-01984-8.