Wednesday, October 16, 2019

The Stink Bug



Descriptively-named, yet elusive in the description of its most striking feature, the Stink Bug has been invading America for a few decades. In New Jersey specifically, it was a good summer for stink bugs (or a bad summer for humans).

The stink bug is like a skunk but in bug form. I guess a skunk would be called a "stink rat" if it was also an invasive species. The bugs are a bit less problematic; they can only squirt 3 inches not 3 feet. Thing is, skunks don't get into your house. The bugs do, especially as winter nears and cold weather sends them seeking shelter inside your walls etc. In Spring, they reappear, this time trying to get back outside.

They don't bite, but they smell. But they only smell if they're threatened. Or if you squish them, releasing their obnoxious defense secretion. And what does that secretion smell like?


I'm paranoid, but for smells. When it comes to my own house, my place of work, or anywhere I have to spend a lot of time, I am constantly, actively smelling my surroundings. Noticing, investigating, researching, remembering. It started with a moldly basement apartment, but now I am hyper-aware of the entirety of my osmic environment.

Hype-aware, that is, except for the things I can't smell. I'm anosmic to putrescene (can't smell semen). You're anosmic to something too, probably. It's common. I once did an "experiment" in my workplace where I had an old smelly tube of paint; it smelled like rotten fish. Some of my coworkers couldn't smell it, and I thought it was strange, so I passed it around to everyone, about thirty people. Three of those people, the ones who didn't jerk their head away after sniffing, they were anosmic to trimethylamine, the smell of rotten fish.

What's more interesting is that one of those people was 50 years old, and he had no idea that he couldn't smell rotten fish. A whole life of smelling, and yet totally unaware of something like that. Around the same time I met a young man who was totally anosmic; he can't smell anything at all. He didn't realize it until he was ten years old, while playing a board game called P.U. The Guessing Game of Smells.


Back to stink bugs. I hear a lot about stink bugs, and being an odor aficionado, I find it hard to believe that I don't "know" what they smell like. (Granted I could settle this by ruthlessly smashing the next one I see, but I'm also so sensitive to smells that the thought of potentially dosing myself just sounds stupid.)

I ask people, lots of people, and you know what they say? They all say the exact same thing, "I don't know...it just smells bad."

I do some superficial searches: For a bug called the Stink Bug, you think there would be more descriptions of its stench. I need to contact an exterminator and ask them. Meanwhile, the best and really the only description is this list of slightly-related descriptors:

Pungent onions
Skunk odor
Strong herbs and spices
Intense-smelling herbs and spices
Rotten cilantro and coriander
Smelly garbage
The odor from the stink bug is due to trans-2-decenal and trans-2-octenal. The smell has been characterized as a "pungent odor that smells like coriander."
-Henderson 2006 below

trans-2-decenal descriptions from The Good Scents Company:
waxy, fatty, earthy, coriander, green, mushroom, sweet aldehydic with a chicken and pork fat nuance, diffusive orange odor with floral, rosey topnotes, citrus peel, citrus flavors especially orange and grapefruit, fruit flavors especially tropical, fried taste somewhat citrusy in dilution

trans-2-octenal descriptions from The Good Scents Company:
fresh, pungent, cucumber, spicy cucumber, green, leafy, herbal, vegetable, banana, waxy, oily, fatty, brothy, sweet, citrus peel, citrus especially orange, fatty notes of nuts especially hazelnut

Image sources:
Stink Bug Side View (pinterest = no copyright protection, good thing for watermarks? PBS)

Notes:
Brown Marmorated Stink Bug - Halyomorpha halys
Green Stink Bug - Acrosternum hilare

Oct 2019, NJ.com


Detecting Stink Bugs/Damage in Cotton Utilizing a Portable Electronic Nose. Henderson, Will; Khalilian, Ahmad; Han, Young (July 9–12, 2006). Oregon Convention Center; Portland, Oregon: Clemson University. [PDF]

Post Script:
The stink bug is an invasive species in the United States. All the invasive species, plants or insects or whatever, seem to be from Asia. I think the real question here is this -- Do they have "invasive species" in Asia? Are our insects invasive to them? And how come I've never heard anyone ask this before?

Post Post Script:
By the way, the stink bug's natural predator? Samurai wasp.

Thursday, October 10, 2019

The Smell of Mother Earth to a Planetary Refugee

In order to survive in outer space, one needs to be protected, first and foremost, from the showers of radioactive particles that abound there. For this, the International Space Station in Neal Stephenson's novel bolts itself to an asteroid named Amalthea (seen here), to rest in its massive "cosmic shade."

This is a story about people who had to flee Earth, barely survived in a hastily-improvised expansion of the ISS, and thousands of years later, flourished long enough to terraform Earth back to its pre-catastrophe days. In a quick passage, he talks about the smell of the air. People have been living in space habitats for generations; they've never smelled air that wasn't recycled; they've never smelled air that wasn't on a planet. But now they're back on a newly terraformed Earth, doing some reconaissance...
"According to their measurements, the result was a nearly perfect reproduction of Old Earth's atmosphere. No one who breathed it after a lifetime spent in the habitats needed scientific data to back that up. Its smell penetrated to some ancient part of the brain, triggereing instincts that must go all the way back to hominid ancestors living on the shores of Africa millions of years ago. As she knew from traveling to Earth many times, it was a kind of intoxicant. It was the best drug in the universe. It made people want to be on Earth more than anyting. ..." (p656)
Post Script
I'm not trying to take away from the awesomeness of this idea, this passage or this story, but chances are that during this scene, the scent referred to is not one of Earth so much as the Ocean. (I think they're standing on the coast when this passage appears.) If that's the case, I should then direct the reader to another post about the smell of the ocean, the chemical Calone, and the Seinfeld episode that made it all memorable.

And if after that you still haven't had enough, check out this earlier post about the smell of rain, which is really the smell of earth (like dirt, not the entire planet).

Notes
Seveneves, Neal Stephenson, 2015


Friday, September 20, 2019

Olfactory Clues To Disease Discovery



Smells can be a great sign of danger, even when it comes from our own bodies. We've got here a story about a woman who smelled Parkinson's on her husband a good ten years before he was diagnosed. This spurred research into the subject, and we now have an idea of what the smell is and how it fits into the effects of the disease.

Tldr, it comes from the production of excess sebum, which contains chemicals known to be related to altered neurobiology associated with Parkinson's. The scent-sensitive woman who noticed it on her husband described it as earthy and musky.

Then there's the nick-of-time test for Maple Syrup Urine Disease. Although the disease can be verified with a blood test, symptoms could get so bad so fast that the time required for this testing becomes prohibitive. Luckily, it can also be identified by sweet-smelling urine, sweat and earwax.

Maple Syrup Urine Disease is a condition where the body can't break things down properly. If our body's natural defense system is inhibited so much that it can't break down the maple-syrup-molecule, for example, then we've got serious problems.

I am not a doctor so I don't know if this is the same smell/molecule, but Sotolon is the "maple syrup molecule." Other things could be exuding from the body, but this is a potent aroma compound, so it's easy to detect.

As a general rule, if you notice that you smell funny, it's something that should be checked out immediately. For example, fishy odor in the urine could be a sign of a urinary tract infection, and the smell comes from the bacteria living there (as opposed to the improper biotransformation of ingested molecules).


Post Script:
Then there's the cancer-smelling dogs, surely we've all heard of that. And for the record, if we interfaced with the world the way dogs do, with smell being way more important, and if we spent lots of time smelling all the things around us, including our own bodies, or those of our loved ones, we might notice these things too. But dogs get the credit, because honestly when was the last time you gave your partner a full body sniff-check?

Notes:
Mar 2019, Inverse

Mar 2019, The Sun

Study about the smell of Parkinson's:

Tuesday, September 3, 2019

Mind Control



It should come as no surprise that we look to others to help us make decisions, whether they're life-changing or everyday decisions. In a new study, we see that when mice choose what to eat, they utilize "taster mice" in their group that are the first to eat from a new food source.

I'm not sure what makes one a taster-mouse in the first place, but they do exist. In order for mice to decide at the colony level whether they should be eating from a certain food source, they don't ask their friends, and they don't check their newsfeed. Instead they use the smell of taster-mice whiskers.

In reality, mice don't do anything. Their brains are programmed by the smell of the taster-mice to steer them towards some food sources and away from others. Their repeated olfactory interactions with the taster mice and the social network they subsequently inform will rewire the neural network in their prefrontal cortex – the place where decisions are made. This alteration links the olfactory cue from the taster-mice to the reward center in the brain, which then motivates the mice to find that smell again.

We can think of all preference as following a similar pattern of social interaction and propagation. Taster-mice function as hubs of their social network. The difference is that humans are a bit more sophisticated. Instead of just transmitting the smell of safe, available food, the hubs of human networks spread styles, preferences, ideas, and information in general.

The interesting corollary is that in mice, the olfactory cues are literally re-wiring the pleasure-seeking centers of their brains, whereas in humans, all kinds of cues can redirect our behaviors. Olfaction is already known to be so tightly integrated with our decision-making and reward centers, but when the actual process by which this takes place is extrapolated to other senses, it suggests that we are way less in control of our own thoughts, desires and behaviors than we may think.


Notes
June 2019, phys.org

Post Script
By the way, casually mentioned in the article that presented this study, was the practice of "erasing memories" in the mice in the study. It's a technique used in optogenetics where a single neuron is zapped. I'm pretty sure it was only a few years ago that we first heard of this technique, and now it's just thrown in there like de rigueur. Eternal Sunshine here we come!

Post Post Script
On Mimetic Desire:
"All desire is a desire to be [someone else]"
-Rene Girard, Quand ces choses commenceront ... Entretiens avec Michel Treguer. Paris: arléa. ISBN 2-86959-300-7. p28. 1994.

Thursday, August 15, 2019

Odor Control


A landfill in New Jersey has been making the local news lately. A perfect storm, literally, is amplifying the stench of its waste emissions, and nearby residents are fuming. Not only is the landfill leachate affected by exceptionally wet weather, but that's where it begins. The extra water acts as a vehicle to bring more garbage goop to the surface than usual, but it also inhibits the fill's methane-capture system. In order to fix these problems, over ten acres of previously-covered garbage had to be uncovered.

Counter to common sense, garbage gets even hotter as it sits there. Microbes break it down, and their "work" produces tons of heat. Uncovering a dump of refuse that's already been rotting is a great was to fill any town with a powerful stench.

Combine all this with the right wind pattern, and you've got a landfill that actually smells like a landfill.

***
Usually, landfills do a pretty good job of smelling like nothing. First, the fill must be chosen or placed in the right spot relative to the interested parties who inhabit the nearby land. Upwind and upstream is the key. Winds don't blow from one direction only, and at certain times of year they can change direction entirely. Water always flows downhill, but the course it takes to get there could change over time depending on the intensity of rain events and changes to the surrounding land, and this could affect fugitive sludge leakage.

Next, there's the bright idea to cap landfills as they go, so their hot gas attack can't launch freely into the surrounding airspace. The gas must escape somehow, so vents are placed around the dump to control these emissions.

That's where the real tech comes in -- the odor control industry. A product called Neutralene, provided by Air Care Technology, is emitted from a vaporization pole. I'm having a hard time telling from their site how it works, but it's one of these two techniques: their product either pairs with the malodors thereby camouflaging them into a less-offensive smell, or it slows down the fugitive offenders by emitting special molecules that attract and combine with the offending molecules, thereby making them heavier, so they fall to the ground before leaving the vicinity of the landfill.

There are other alternatives to maintaining a garbage dump. We could burn it, using the heat produced for power generation. We could compost it, using the by-product to fertilize farmland. (We could even recycle…). But even these solutions can’t keep up with demand. We will have landfills for a long time, if not forever. And as long as we have landfills, we will have the smell of landfills.


Notes:
March 2019, NJ.com


Related Links:
Limbic Signal, 2018

Limbic Signal, 2017

Limbic Signal, 2017

Limbic Signal, 2017

Limbic Signal, 2017

Limbic Signal, 2017

Limbic Signal, 2016

Limbic Signal, 2016

Thursday, July 25, 2019

On Carbon Footprints and Cognitive Decline

 
We didn't always spend most of our time indoors. Some of us still don't. From a global perspective, most of us still don't. But for most of those living in the developed world, more time is spent indoors than out. Human-body-pollution is not a problem outside, where it is maximally distributed. Indoors, anything that is generated will accumulate, and unless it is exhausted abundantly, it can have adverse health effects. Even our own breath can fill the air until it reaches concentrations that actually have effects on cognition (according to this pretty good study, at least.)

I never thought of myself as a smokestack, as an incinerator burning garbage and belching toxins. But then I read a book called The Metabolism of the Anthroposphere, where I learned that half of all the matter we ingest will then leave our bodies not as solid waste and not as liquid waste. Half of everything we eat, by weight, is exhaled as carbon dioxide, and as the by-product of energy production. We burn food for energy, and emit the by-products like a tailpipe.

Cows release carbon dioxide when they breathe too, because they are also burning food to fuel their bodies. And just like coal power plants, except that their bodies are the infrastructure of our anthroposphere.

These emissions may be bad for the planet, but when humans do it, it's only a problem indoors. This hasn't been known as a problem until recently. Coincidentally, it's also a problem that has been getting worse. Then again, some of us might argue that the effect, reduced executive decision-making proficiency, is not a problem at all(!).

***
The history of fresh air vs human offgas may traverse a few threads. Sure, to this day people live in overcrowded and underventilated conditions. Sure squared, too many of us are exposed to pollutants that are magnitudes more harmful than CO2, and not just to our cognitive function but to organs and critical systems.

This is a first world problem. And that the very few of us on the planet of a swelling 7 billion can worry about lowering their high-level executive decision-making abilities, means there are a few less of us worrying about dying at 30 years old due to excessive inhalation of machine-generated combustion by-products indoors, for example.

That being said, we have made progress in limiting harmful exposures in the workplace and in the home. But we have neglected ourselves as a point source of pollution. And baked into our building practices from 1970 to 1990 (roughly) are energy efficient strategies that are really good at making sure we stay cooped up in a pool of our own breath.

So to recap, once we get rid of all the really harmful pollutants in the workplace – respirable particles, inert mineral fibers, toxic chemical vapors, biologically-active dust – we then start to consider the relatively invisible threat of carbon dioxide.

And why should we care; is it really a threat to human health? Maybe not. But it is a threat to our mental health. Being in a room that is poorly ventilated so that it contains double the amount of CO2 found outdoors (and generated by the exhaling human occupants) makes you a bit less sharp (actually a lot less sharp, see more details below). Double that even more, and people get even less sharp.

Trying to prove that anybody was ever killed by being less sharp is like trying to implicate climate change in a single heat wave. But there are some people who care about this – those whose job it is to provide facilities designed for people to think. Not to build cars or computer parts or to make perfumes, but to think. Classrooms are thought chambers. What is the most important thing people are doing in that space? Thinking.

Executive conference rooms are thought chambers. The small amount of people in that one room could be making decisions worth a lot of money. What if they could think 30% better, whatever the heck that means.

How about we should all want to think better. We should all want as much fresh air as possible indoors at all times. That doesn't come without a cost. You have to heat that outside air, or cool it, or take the water out of it, or put it back in, and filter and circulate. That all costs money, especially the heating and cooling.

How much is it worth to do one thing that would get every student to think a little bit better? How much does it cost to condition their fresh air during a cold snap or a heat wave? How much is it worth for a group of six entrepreneurs to craft a plan that's a little bit better?

It may take a while for us to reach the point where we can begin to care about these things, but this is the logical next step.

Progress will march on, and as more and more of the world spends their time indoors, (and cleans up their act so they are no longer worried about physically harmful pollutants), then more and more will be looking for the next improvement in their environment. And this is final frontier, removing our own carbon dioxide from the equation.


*Body odor is not known to be a health hazard, although the WELL Certification regimen, for assessing the health and wellness of the insides of a building, includes criteria for "Olfactory Comfort;" Designers can obtain credits for providing abundant exhaust/fresh air, or for controlling and limiting the migration of odors, problems that occur to the human occupancy of interior spaces.

**It should be noted that this study, and those like it, do not tell us how carbon dioxide negatively affects our cognition, just that it does, or at least it did on the tests they administered.


Post Script
Jun 2019, phys.org

Squalene, which is the greasy, grimous protective substance that once accumulated on your skin, interacts with ozone to produce secondary pollutants.

infographic image source

Notes
By Veronique Greenwood, The New York Times, May 6, 2019


Is CO2 an Indoor Pollutant? Direct Effects of Low-to-Moderate CO2 Concentrations on Human Decision-Making Performance. Usha Satish, Mark J. Mendell, Krishnamurthy Shekhar, Toshifumi Hotchi, Douglas Sullivan, Siegfried Streufert, and William J. Fisk. Environmental Health PerspectivesVol. 120, No. 12. 1 December 2012. https://doi.org/10.1289/ehp.1104789


Associations of Cognitive Function Scores with Carbon Dioxide, Ventilation, and Volatile Organic Compound Exposures in Office Workers - A Controlled Exposure Study of Green and Conventional Office Environments. Allen, Joseph G., Piers MacNaughton, Usha Satish, Suresh Santanam, Jose Vallarino, and John D. Spengler. 2015. “Associations of Cognitive Function Scores with Carbon Dioxide, Ventilation, and Volatile Organic Compound Exposures in Office Workers: A Controlled Exposure Study of Green and Conventional Office Environments.” Environmental Health Perspectives 124 (6): 805-812. doi:10.1289/ehp.1510037.

We simulated indoor environmental quality (IEQ) conditions in “Green” and “Conventional” buildings and evaluated the impacts on an objective measure of human performance: higher-order cognitive function.

On average, cognitive scores were 61% higher on the Green building day and 101% higher on the two Green+ building days than on the Conventional building day (p < 0.0001).

Cognitive function scores were significantly better under Green+ building conditions than in the Conventional building conditions for all nine functional domains.


W. J. Fisk. Indoor Air - International Journal of Indoor Environment and Health. 06 July 2017. https://doi.org/10.1111/ina.12403

There is compelling evidence, from both cross‐sectional and intervention studies, of an association of increased student performance with increased ventilation rates.

The net annual costs, ranging from a few dollars to about 10 dollars per person, are less than 0.1% of typical public spending on elementary and secondary education in the United States.