Melissa:
01:57
Hey. I'm Melissa.
Jam:
01:58
And I'm Jam.
Melissa:
01:59
And I'm a chemist.
Jam:
02:00
And I'm not.
Melissa:
02:01
And welcome to chemistry for your life.
Jam:
02:03
The podcast that helps you understand the chemistry of your everyday life.
Melissa:
02:06
Are you ready to learn more about smells?
Jam:
02:09
I am so ready.
Melissa:
02:11
We're gonna talk about why something smells so strongly bad to us.
Jam:
02:16
Okay.
Melissa:
02:16
You're gonna tell it back to me, and then I'm gonna give you some fun smell facts as a bonus for your Proper explanation.
Jam:
02:25
Okay. So, basically, everything, all these fun facts are riding on me getting this right.
Melissa:
02:32
Just the 2 fun facts. Yeah.
Jam:
02:33
Okay.
Melissa:
02:34
At the end.
Jam:
02:34
Alright. Alright, folks. Be cheering me on. For all of our sake, we get to hear these cool fun facts if I get this right. So
Melissa:
02:43
Okay. So we talked about our olfactory receptors last time Uh-huh. That those are controlled by genetics. There are about 800 in humans. 400 of those seem to be active.
Melissa:
02:55
Okay. There's 1,000 in mice in case you're wondering.
Jam:
02:58
Woah. That are active?
Melissa:
03:00
I don't know if they're active. And about 10 no. And about 100 in monkeys, I think.
Jam:
03:09
What about dogs?
Melissa:
03:10
I don't know. Probably more.
Jam:
03:11
Yeah. Because they're, like, all about the nose.
Melissa:
03:13
I did read a book, About forensic science that said that the reasons that dogs could smell part of like, how dogs could smell so well and why they wrinkle up their face is they hold the smells in their wrinkles, and then they can sort of unfurl to get a little reminder what it smells like. And the reason their ears kind of are so long is so they can kick up the smells with their ears.
Jam:
03:38
I heard about the the ears thing only because One of my dogs is a beagle, and he's got long ears. And he's he's bred for that kinda deal for hunting.
Melissa:
03:47
And he can find smells. Oh, yeah. One time, he destroyed he didn't really destroy. One time, he made a significant material alteration to a backpack of mine in search of
Jam:
03:58
Yeah.
Melissa:
03:59
Empty Tupperware that had once contained food, but didn't anymore.
Jam:
04:02
Yeah. He, caused a wardrobe malfunction on your backpack there.
Melissa:
04:06
A 100%.
Jam:
04:07
Yeah. And that's a common thing. I mean, like, a lot of dogs can do that, but any sort of hound can is, like, even more smell Driven. Like, it's almost like
Melissa:
04:17
you're driving crazy. Inside a backpack. Inside a lunchbox. Yeah. In a closed Tupperware.
Jam:
04:23
Inside of a safe in the ocean, and he still got it.
Melissa:
04:29
But I kept using that backpack until it got doused in dichloromethane.
Jam:
04:32
Oh, okay. And that did he do that too?
Melissa:
04:35
That he was in the lab, and there was an accident.
Jam:
04:37
Yeah. Yeah. He yeah. He's a little clumsy.
Melissa:
04:40
Okay. So
Jam:
04:41
Without thumbs.
Melissa:
04:42
Different ones of those different receptors will detect for different things. Okay. Okay. One major class of smells Mhmm. That we detect for is a sulfur containing compound called thiols.
Jam:
04:59
Okay.
Melissa:
05:00
Thiols are also sometimes called Mercaptans Okay. Because they react with Mercury. They're Mercury capturers, so mercaptains. Mhmm.
Jam:
05:11
Like a mer like a mermaid or merman, but it's a captain.
Melissa:
05:15
Except a mercury captain.
Jam:
05:17
Got it.
Melissa:
05:17
Mercury cap Div taker.
Jam:
05:19
Okay.
Melissa:
05:20
So Mercaptans or thiols are interchangeable. People have heard those before. I think it's a fun name, Mercaptans. And now this is in response to a question that we asked were asked after our hair episode
Jam:
05:35
Mhmm.
Melissa:
05:35
From Joey h. Mhmm. The question was, why doesn't our hair smell bad like sulfur? In the class of sulfur compounds that we usually can detect so strongly Mhmm. Is actually sulfur bonded to a hydrogen.
Jam:
05:50
Okay.
Melissa:
05:51
That's a special functional group. Uh-huh. We talked about functional groups being an arrangement of atoms back in the very first episode that we talked about amino acids, the Maillard reaction. Mhmm. And that functional group is any carbon containing compound with a sulfur bonded to a hydrogen.
Melissa:
06:10
Okay. So those have the smell that we detect for. That functional group, I do not think is present in our hair.
Jam:
06:18
Okay.
Melissa:
06:19
It's Sulfur is bonded within the bigger system of the cysteine.
Jam:
06:23
Mhmm.
Melissa:
06:25
So that's answering Joey's question. Shout out, Joey. But we do detect for the thiol smell. Now what's interesting Uh-huh. Is thiols are very similar to alcohols.
Melissa:
06:38
Okay. Alcohols are a functional group with an oxygen bonded to a hydrogen.
Jam:
06:43
Okay.
Melissa:
06:44
So instead of a sulfur bonded to a hydrogen, it's an oxygen bonded to a hydrogen.
Jam:
06:48
Got it.
Melissa:
06:49
And sulfur and oxygen are in the same column on the periodic table. Uh-huh. And, usually, if you switch out those atoms that are in the same column, they will have very similar chemistry.
Jam:
06:59
Oh, interesting.
Melissa:
07:00
Because they have the same number of electrons around them. Mhmm. They are usually very similar, not exactly the same.
Jam:
07:06
Got it.
Melissa:
07:07
In this case this is amazing to me because I'm so used to alcohols and thiols reacting and acting Similarly, in chemical environments Uh-huh. We are 100,000,000 more times sensitive to Sulfur compounds, the thiols, then the alcohol compounds.
Jam:
07:30
Really?
Melissa:
07:30
With a very similar structure with very Similar chemistry.
Jam:
07:34
Uh-huh.
Melissa:
07:35
We are 1,000,000 more times sensitive to 1 than the other.
Jam:
07:40
What the heck?
Melissa:
07:41
Isn't that amazing?
Jam:
07:42
Yeah. A 1000000 times is a little excessive.
Melissa:
07:44
Not 1,000,000. 100,000,000.
Jam:
07:47
Oh my gosh. Couldn't it just been 10? Like, how why do we need it to be so high?
Melissa:
07:52
Well, it's because of survival.
Jam:
07:55
Oh, okay.
Melissa:
07:56
Those thiols of sulfur containing compounds are in rotten food, dead animals Mhmm. Poisonous gases, not all poisonous gases, but some.
Jam:
08:05
Yeah.
Melissa:
08:05
And even some carnivores, which would theoretically be our predators Uh-huh. Can sweat out and excrete Sulfur containing compounds in their sweat, so it's almost for safety.
Jam:
08:18
Woah. That's crazy.
Melissa:
08:20
Isn't it? Yeah. I, Literally, the next line I have written is, which is crazy.
Jam:
08:26
Did I ever tell you I think I did tell you this, but I don't think I told you on here. About when I posted a story about sulfur, like geothermal pools and stuff like that when we're in New Zealand. There's there's a specific
Melissa:
08:41
Yes.
Jam:
08:42
Town we're in called Rotorua, which seriously, no matter where you go in Rotorua, it Does smell like sulfur. They it's so much geothermal interesting. Yeah. So many geothermal pools and, like, steaming Pools and even just kind of steam coming out of the ground in different places, stuff like that, just so geothermal active everywhere Mhmm. That the entire Town smells like sulfur.
Melissa:
09:06
So a little bit like rotten eggs? Yes. It was a great smelling town.
Jam:
09:10
It was rough. But, like, obviously, the pools looked super cool.
Melissa:
09:13
And it had a
Jam:
09:13
super cool forest there too. So it's like, okay. It doesn't smell like I'm in a garbage dump, but yikes. Does it is it hard to stick around here? We didn't say that.
Jam:
09:22
We just We're like, let's hang out. Let's look at this stuff. We ate some food, which actually was okay because we were got inside, and it smelled more like the food. But Everywhere else we went smelled like sulfur. Interesting.
Jam:
09:34
So we're like, let's let's get out of here.
Melissa:
09:35
I wonder how those people's noses have changed and adapt to that Going on Yeah. The people who live there.
Jam:
09:40
They were new. It was a big touristy place because of all the things that you could see. So it was, like, plenty of people go there by choice And stay there. So I don't know, man.
Melissa:
09:50
That is fascinating.
Jam:
09:51
It's crazy.
Melissa:
09:52
Well, according to some chemist, They believe Mhmm. That there's an enhanced reactivity to these compounds in our olfactory sensors Mhmm. Because Our body has figured out to use the copper in our bodies to enhance the reaction to it.
Jam:
10:12
Oh.
Melissa:
10:13
Yes. So it was hard for me to understand in this paper that I was able to find if it was because The copper enhances the binding so more molecules are able to bind. Uh-huh. It's called a binding constant. So is there more molecules binding for the same concentration, or if it just somehow the copper makes the signal stronger without making the actual binding of the molecule stronger, but the presence of copper and I think there's not a ton known about this because it was a relatively recent paper.
Melissa:
10:46
The the presence of copper Mhmm. With Specific olfactory receptors will enhance the awareness of sulfur thiol compounds, and that's why we smell it so strongly. And I feel the author put it better than I can.
Jam:
11:03
Okay.
Melissa:
11:03
So I'm just gonna quote from this paper about Copper in olfactory reception.
Jam:
11:08
Okay. Sweet.
Melissa:
11:10
The absence of a metal effect in an extensive screening using, Just to paraphrase other olfactory receptors for ligands, including alcohols, amines, sulfides, Diols and carboxylic acid indicates the metal effect now present in both humans and mice may be a restricted phenomenon within an organism's olfactory system and may be specific to certain compounds where Sensitivity is of utmost importance. So translated, that means that the metal effect essentially is very rare And only used in instances where it is very, very important likely for survival, like in the case of thiols.
Jam:
11:57
Mhmm.
Melissa:
11:58
Isn't that amazing? Yeah. And this is in the presence of copper, which is naturally occurring in our body.
Jam:
12:06
That is so weird. What the heck? I know. So stinking weird.
Melissa:
12:13
So this paper just came out in 2016 Mhmm. And it gives a lot of information on how one specific olfactory receptor will respond specifically to thiol odorants with ionic copper to activate strongly. Mhmm. It doesn't give a lot of the mechanism that I can understand because it gets back into that physiological side, but it makes clear that alcohols are unreactive in this same olfactory receptor. It's pretty incredible.
Melissa:
12:42
And this again was in 2016, which is not that long ago. Yeah. So I would assume that a lot of Smells and what's going on with this is still being discovered. This is one of the first times that they could find copper's role in human olfaction. They said it hadn't been demonstrated before Mhmm.
Melissa:
13:01
This paper. So that's kind of a new thing that's recently come out that copper is something that plays a part in the activation of these olfactory receptors, but they are likely Part of the 100,000,000 fold improvement between regular old alcohols and Bios.
Jam:
13:23
It's so, so nuts. Isn't it? You already thought about? What? Well, I was just thinking like, why do I need to be that strong?
Jam:
13:31
But what if it's that sulfur okay. So you can make a robotic nose. Mhmm. It smells everything the same. Mhmm.
Jam:
13:41
Based on how much of the molecules are in the air.
Melissa:
13:44
Mhmm.
Jam:
13:44
So, like, if you got a cup of coffee right near it, it's gonna be smelling coffee. If you got one further away. Might be feeling lost. Whatever. Yeah.
Jam:
13:51
What if there's actually, like, not tons of the sulfur molecules in the air, but it's just that we're so good at smelling it that that's why it smells so strong.
Melissa:
14:04
Right.
Jam:
14:04
Like, what if there isn't a lot of it? It's just that we're like Like, oh my gosh. What is that smell? And it's like, there's a little bit
Melissa:
14:10
one of the possibilities.
Jam:
14:11
And our bodies are like, There's sulfur, and they Make us smell it really strong.
Melissa:
14:17
So that is definitely what's happening. There are less sulfur molecules in the air. We can detect them A 100000000 times easier.
Jam:
14:26
Yeah.
Melissa:
14:27
So if there was 1 sulfur molecule in a 100,000,000 alcohol Molecules, we would detect the sulfur containing thiol the same as the 100,000,000 alcohol molecules. Gosh. Crazy.
Jam:
14:42
Yes. Very crazy.
Melissa:
14:44
But the question is about the mechanism behind that Yeah. And how does it do that? Mhmm. Is it that The one binds more strongly somehow because of the copper, or what? What is the mechanism that's making that signal so much stronger.
Melissa:
15:01
Right. Right. Copper seems to play a role in the enhanced detection. Yeah. But from what I can find, we haven't elucidated that yet.
Jam:
15:08
Got it.
Melissa:
15:09
There are likely people right now who are doing research on this.
Jam:
15:14
Mhmm.
Melissa:
15:14
Because in the chemistry world, 2016, 2019 as a second paper on that would be a pretty quick turnaround.
Jam:
15:21
Yeah.
Melissa:
15:21
It
Jam:
15:22
and think about 2020.
Melissa:
15:23
Yeah. So that would be very quick. So things are still happening Yeah. For sure. So that's my guess as to where they're at with this.
Melissa:
15:33
So there's still research going on, and we're gonna learn more. So it's not as satisfying as some of the other topics, but that's because I'm talking to you about research that is going on right now.
Jam:
15:42
This very moment Mhmm. Someone or many people are chipping away at trying to figure this out.
Melissa:
15:48
Right.
Jam:
15:49
That's so crazy.
Melissa:
15:51
So that's a shorter one, but that's why We smell smells Yeah. The way that we do. Yeah. Thiols, bad smells. And I was gonna tell you some things that have Those thiols in them Uh-huh.
Melissa:
16:05
Rotten eggs Uh-huh. Durian
Jam:
16:07
Uh-huh.
Melissa:
16:08
Rotting food. Like, The other day, one of my roommates left chicken in the refrigerator for over a week. Smelled horrible. I wanted to die.
Jam:
16:17
That's so weird. A week is not that long.
Melissa:
16:20
It had gone bad over a week ago.
Jam:
16:22
Oh, got it. It was bad for a week. Okay. Got it.
Melissa:
16:24
Yeah. I
Jam:
16:24
was like, that's okay.
Melissa:
16:27
It was bad. Or And it was in a in a grocery bag. So I was like, what's in here? And I opened it.
Jam:
16:32
And I
Melissa:
16:32
was like, I'm gonna die.
Jam:
16:35
Also, Like we talked about 2 weeks ago, the chemicals for Permian Mhmm. That smell, like we talked about. Mhmm. It's interesting how that Went from that to this, and it wasn't like it's set on purpose?
Melissa:
16:48
Right. It's Ammonium Thioglacolate, I believe. And so thio is because there's a thiol
Jam:
16:55
Cash.
Melissa:
16:55
In that compound that they put on your hair. Fascinating. Right?
Jam:
17:01
This is way cool. Yeah. That's crazy.
Melissa:
17:04
So that's all I have for you. If you can explain that back to me, kind of a weird abstract one to explain Mhmm. Then I'll give you 2 fun facts about our noses and smelling.
Jam:
17:15
Okay. I'm gonna try.
Melissa:
17:17
Great. I believe in your ability.
Jam:
17:20
Everybody, Cheer me on from your respective cars and headphones, and
Melissa:
17:25
let's hope
Jam:
17:26
we all get these fun facts as a reward. Okay. So Bad smells. There's 2 types of main what is that? Chemicals or compounds or categories of Of stuff, thiol and alcohol?
Melissa:
17:42
Well, those are just 2 really similar things. Alcohols And thiols have really similar chemical properties, but for some reason, one interacts with the nose like, woah, and the other one doesn't. They're very similar chemically.
Jam:
17:56
They're worth comparing because they're similar similarly.
Melissa:
17:59
Yes. Like, if I dunked 1 in a reaction and the other in a reaction, they would act very similarly.
Jam:
18:03
Okay.
Melissa:
18:04
They have very similar properties chemically.
Jam:
18:07
Which is why their comparison is so interesting because when it comes to our noses, they're so different.
Melissa:
18:11
Yes. Which is baffling.
Jam:
18:13
So For instance, like the sulfury bad smells
Melissa:
18:17
are a
Jam:
18:17
lot of times thiols. Mhmm. And This recent information
Melissa:
18:24
Mhmm.
Jam:
18:25
From 2016, Says that copper, which is already just in our bodies, and we already have a a stockpile of it, I guess Mhmm. Helps us be able to crank up our ability to be sensitive to The smells of thiols and sulfury type of bad smells? Yes. Kind of like. My my thought would be like kinda like Wi Fi versus Ethernet.
Melissa:
18:58
Oh, okay.
Jam:
18:59
So Wi Fi, it's there. Even if you get a good signal, it's it's there, and you can connect and stuff like that. But as soon as you plug in Ethernet, You have a direct connection. Your Internet speed is gonna be way faster.
Melissa:
19:15
Yeah.
Jam:
19:16
Insanely faster. So you get a little copper in there. Not Totally certain, yeah, exactly what thing it's doing. But somehow, the copper just immediately the better connection or allows It to have be more sensitive or
Melissa:
19:31
Boost that signal.
Jam:
19:33
Something. Yeah. That just boosts the signal a lot, and it's not like there's More abundance. That's why I picked that. Yeah.
Jam:
19:39
It's not like you suddenly got more Internet because you switched Internet service provider or something like that. It's like you just take A different path. You're you're introducing something new.
Melissa:
19:50
Right.
Jam:
19:50
And it just makes the signal way stronger.
Melissa:
19:53
That is a great way to describe it.
Jam:
19:55
And so you get that copper in there, and then you can smell those bad smells way better. It's just so nice that we can do that now. So thanks, copper.
Melissa:
20:03
That is a really good description. Yeah. I mean, this one, I was worried because it's kind of abstract. It's Yeah. I don't have a lot of answers.
Melissa:
20:10
There are still a lot of questions. And those Thial chemists, copper nose chemist, if you're out there, please reach out to me. I'd love to have a conversation about how you would explain this to to us and give us more information in detail. Mhmm. But until then, this is what we have.
Melissa:
20:25
And a lot of science is this is what we know right now.
Jam:
20:28
So I
Melissa:
20:29
was a little worried, but you knocked it out of the park.
Jam:
20:31
So that means we get the reward. Right?
Melissa:
20:33
That means you get the reward. So I've got 2 fun facts for you.
Jam:
20:36
Okay.
Melissa:
20:36
1, why do some things Not smell.
Jam:
20:40
Yeah. Why don't they?
Melissa:
20:41
Yeah. Why don't they? It's a weird, you know, it's a weird thing that some don't smell. There's 2 reasons that I can think of.
Jam:
20:47
Okay.
Melissa:
20:48
1 is some things don't vaporize, really. Mhmm. Metals don't have a super strong smell Mhmm. Because it's hard for them to rise.
Jam:
20:55
Right.
Melissa:
20:56
Sometimes I think we get metal ions, and maybe we have some of that. But Mhmm. But metal is not gonna smell as strongly as, like, fresh baking bread.
Jam:
21:03
Right. Right.
Melissa:
21:05
So sometimes things just don't vape vaporize. Mhmm. Some things do vaporize, and we can't smell them.
Jam:
21:11
Okay.
Melissa:
21:12
We call those odorless. Mhmm. My suspicion is, although I was not able to confirm this Mhmm. That there's no olfactory receptors for those things to signal a smell.
Jam:
21:24
Bad.
Melissa:
21:24
Because I don't think I think the only thing that makes something odorless is that we can't smell it. Mhmm. But can we not smell it because it doesn't have a smell, or can we not smell it because we don't?
Jam:
21:34
Have the ability to understand it or, like Yes. Receive it.
Melissa:
21:39
So I was wondering if mice have one Thousand olfactory receptors. Mhmm. Can they smell things that we can't smell? Maybe carbon monoxide has a smell to them. Yeah.
Melissa:
21:50
So I was just thinking about that. Dude.
Jam:
21:52
Yeah.
Melissa:
21:52
That was a fun thing to stir in there.
Jam:
21:54
Mhmm. I like that.
Melissa:
21:55
Kinda like, are there colors that we can't see?
Jam:
21:58
Yeah. The whole mantis strip thing we talked about. Exactly. Whatever that whenever that was for Radiolab. Yeah.
Jam:
22:04
That's crazy. It would make sense that that'd be the case.
Melissa:
22:06
You can
Jam:
22:06
have more receptors. Be sensitive to more things because surely maybe you can make that argument, like, the hound dog thing. Like, maybe they have more and they can smell more. So, like, That's why they can trace a person.
Melissa:
22:19
Right.
Jam:
22:20
It's like they can smell all these things that we can't Yeah. That we think they'll have a smell.
Melissa:
22:24
Interesting. Right?
Jam:
22:25
Yeah. That's crazy.
Melissa:
22:27
The other thing Mhmm. Is not all thiols smell bad to us.
Jam:
22:32
Uh-huh. It
Melissa:
22:33
could be the dosage at which they start to smell bad. I Couldn't also find a ton of information on this.
Jam:
22:39
Mhmm.
Melissa:
22:39
But there are thiols in Citrus fruit.
Jam:
22:45
Mhmm.
Melissa:
22:45
Like grapefruit.
Jam:
22:47
Mhmm.
Melissa:
22:47
There are thiols present in that, but it smells good to us. Uh-huh. And they tested to see if it was above or below human detection limits, and it is above the levels of human detection limits in fresh squeezed grape Fruit juice or orange juice. There are thiol vapors present.
Jam:
23:08
That's so weird.
Melissa:
23:09
But somehow it combines with all the other things going on That it doesn't smell like rotten next to us.
Jam:
23:15
Yeah. Yeah. I I would even have thought that they'll be, like, on totally different spectrums of stuff chemically with the smells. Like, I would have just thought, you know, sweet, citrusy, kinda tangy smells over here.
Melissa:
23:30
Right.
Jam:
23:31
Horrible sulfur y smell over here. I just not would have would have not thought they have anything in common at all.
Melissa:
23:37
Yeah. It was super interesting. There was a whole long, long List. There's a paper that just basically took every compound and identified every single molecular compound Mhmm. Molecular present in grapefruit and citrus fruits.
Melissa:
23:54
And There is a special thiol that they call the grapefruit thiol, but there's also, I think, hydrogen sulfide gas was one of the things that was present, which is what makes rotten eggs smell bad. Man. Isn't that weird? Yeah. So I thought those were 2 fun, weird facts that don't take a or need a lot of explanation, but are just Interesting.
Jam:
24:15
That is really interesting.
Melissa:
24:16
So there you go.
Jam:
24:17
Wow.
Melissa:
24:18
That's the chemistry of smells.
Jam:
24:19
The mystery and the craziness of Smells continues. We learn a little bit, but we're also having more questions as we go.
Melissa:
24:27
Yeah. And smells that work in 1991. It was one of the last Ones of our senses to be fully elucidated or to be again being elucidated. Yeah. So I thought that was interesting too.
Melissa:
24:39
I learned a lot about smells. It was really fun preparing for this episode, but I think I still have a lot of questions. And I'm hopeful that I will learn more And maybe even be able to meet some of the people doing this work so that I can teach you guys more.
Jam:
24:54
That'd be awesome. I'd love that.
Melissa:
24:55
So that's all for the chemistry. Let's move into talking some about our weeks.
Jam:
25:00
Deal. So I had a good week. I've been Burning the midnight oil.
Melissa:
25:06
Oh, have you been?
Jam:
25:07
Working hard.
Melissa:
25:08
Working hard or hardly working?
Jam:
25:11
It you could call it either. I've been trying to catch up on movies.
Melissa:
25:16
Oh, interesting. Okay.
Jam:
25:19
The Oscars are coming up.
Melissa:
25:21
Well, yeah, because you're gonna have a child tune, and Mhmm. Your brain's not gonna do very well Yep. When it's that sleep deprived to actually be able to Take in the movies.
Jam:
25:30
Yeah. I'm I'm not sure how many years more I can try to keep up with the Oscars deal. And I don't like, you know, keep up with every single category. But I always use the best picture nominee list as a list of ones that I'll see. And there's many times that really good movies are not in that list, so it's not perfect at Aw.
Jam:
25:47
It's pretty flawed sometimes. And some years has been super flawed, head scratchingly flawed.
Melissa:
25:53
Head scratchingly flawed.
Jam:
25:55
So but this year, I think it's pretty good. And Okay.
Melissa:
25:58
So I've
Jam:
25:58
been trying to catch up on watching those movies.
Melissa:
26:00
I know nothing about movies.
Jam:
26:02
So Okay. Well, here's a list. I'll tell you which ones I've seen and in the order to fight
Melissa:
26:05
that. Okay.
Jam:
26:06
So I'm ready. The first one I saw was Once Upon a Time in Hollywood. It came out
Melissa:
26:09
Oh, I did see that one.
Jam:
26:10
Fall, I think, fall. Summer. Summer? Was it really? Yeah.
Jam:
26:13
You're right.
Melissa:
26:13
It was when I just moved in with my new roommates.
Jam:
26:16
So Summer, I saw that one. And then I saw Jojo Rabbit, I think in, like, November sometime? Mhmm. And those were the only ones I had seen on this list. And then I haven't
Melissa:
26:27
been told to see Jojo Rabbit, but I have not been able to do so.
Jam:
26:30
I think you'd like it.
Melissa:
26:31
Okay.
Jam:
26:32
It's there's a little bit of everything in there in a surprising way. It's funny and irreverent and also then, like, Really, really critical and thought provoking, and then also sad.
Melissa:
26:43
Now but I hate Wes Anderson, and I get the feeling it might be like Wes Anderson movies.
Jam:
26:48
I don't I would not say that it's like that.
Melissa:
26:51
Okay. Alright. I trust you.
Jam:
26:52
It just I think partly because it takes place in such a real scenario even though there's a lot of, like, Fictionalized elements to it. It's based on a real book. All of Sanderson's stuff for the most part is, like, totally fiction, his own universe kinda deal. It's like this is Hitler youth, Nazi stuff going on.
Melissa:
27:09
Okay.
Jam:
27:10
Saw that one in November. And then In the last 2 weeks or maybe I should say, like, 3 based on when this one comes out, this episode, I've seen, Little Women.
Melissa:
27:22
How was that? I really wanna see that one.
Jam:
27:25
Super good. Haven't not watched the old ones. So and I don't care to see them. I'm not I'm
Melissa:
27:28
not gonna watch you now. Book?
Jam:
27:29
Nope. But I would read the book. Marriage Story, very sad. Very good.
Melissa:
27:35
That was on Netflix right now.
Jam:
27:37
Yes. It is. Go watch it now. And I want you alone. Not gonna give a review of all these.
Jam:
27:43
And then I saw, 1917 and saw a joker. Actually, I saw a joker before, All those. And then I'm almost with the Irishman. I've had to split into 3 sessions because it's, like, 3 and a stinking half hours long.
Melissa:
27:56
Wow. That's a very, Very long.
Jam:
27:59
It's the one I was looking forward to watching the least, and I've been surprised by it the most because I was so Thinking I would hate it and thinking that Yeah. I'd be waiting for it to be over.
Melissa:
28:08
So below expectations often leads to being present pleasantly surprised.
Jam:
28:12
It really does. So just think all these movies are gonna suck and then go see them all. Okay. But the accurate is better than I expected, and, break it up into 3 parts. You might feel the same way.
Jam:
28:21
The only ones I'd have to see are Parasite and Ford versus Ferrari. So close. And then it makes it really fun to watch the Oscars and try to see which one's gonna win because you feel pretty informed, at least, about the main ones.
Melissa:
28:37
And your degree is in film. So this, in a lot of ways, is is, like, an exercise in your professional opinion and and critique and skills.
Jam:
28:47
Yes. And it is really fun. I mean, there's so many movies that come out every year. It is fun to be kinda given a list of, like, here's some really highly regarded ones from this year. Mhmm.
Jam:
28:56
Go check these out. There's also a lot of other really good movies that came out, but it's kinda cool to see this and then try to predict which thing is gonna win or root for 1 that you really want to win.
Melissa:
29:06
Yeah. I think it's hard to imagine what that would look like in the chemistry world. But if there was one of those in my profession, I would really
Jam:
29:12
Yeah.
Melissa:
29:12
I would enjoy something like that. Okay. Review all these things, like Presentations or something from some of these renowned maybe Yeah. The Nobel Peace Prize.
Jam:
29:20
But Yeah.
Melissa:
29:21
You know, it's hard to know all the research that goes on in the world.
Jam:
29:23
So
Melissa:
29:24
That is really cool. I I could see how that, especially given your field, would be one of the things you look forward to Every year.
Jam:
29:31
Yes. And a couple years ago, the movie I was really cheering for as kind of an underdog did win, and it was such a cool year that have it's been, fun to to be as into the Oscars since then. But yeah. So that's been my week and last couple weeks.
Melissa:
29:47
Would you mind telling me what the movie that you really hoped Would win that did win was?
Jam:
29:51
It was Moonlight. Oh. And it beat La La Land, and it was a whole deal because the envelope accidentally got switched.
Melissa:
29:57
Did you
Jam:
29:57
read that?
Melissa:
29:57
Mhmm. And there was a very interesting, I think it was Radial Lab about, human error and oh, no. I think it was 99% invisible. Mhmm. It's about human error and poor design and how that envelope could have been designed
Jam:
30:12
Fox did meant to. Yeah.
Melissa:
30:14
Much better
Jam:
30:15
Yep. Mhmm.
Melissa:
30:16
To avoid the human error. And the fact that they didn't Anticipate the human error is ridiculous.
Jam:
30:21
Yep. So Moonlite won, and I was cheering for it from the very beginning. And it really deserved to win, for sure.
Melissa:
30:27
Wow. That's so cool. I haven't seen moonlight or la la land.
Jam:
30:30
Definitely seen moonlight. What about you? What's been going on this week for you?
Melissa:
30:34
One thing that I've been notice noticing and really appreciating lately is my students. And I talked about this some at the end of last semester, but
Jam:
30:42
There
Melissa:
30:43
are just such a bright spot in my days weeks where they will hang out in the area outside my office, and they Have formed a there's a kind of a core group that's formed a study group, and anytime anyone else comes around and asks questions, they're happy to help. It's just really a nice, Inspiring thing to see in students who are struggling in a class that can be very hard. And so It's just really an enjoyable part of my of my week and semester in life, really, where I get to see them be kind to one another, and I've gotten to grow to know them and know about their lives and enjoy their kind of unlikely friendships with one another. And So no matter else no matter what else is kind of going on in my life at this time, like, if I'm stressed or I've got school or whatever, when I'm working with them, all the things I have to do leave my mind, and I just am able to zoom in and enjoy Seeing them learn and grow and help each other. So that's been something that I've really, really enjoyed over the last several, Really several months because even into last semester.
Jam:
31:50
That's awesome. I even met a few of those guys talking about today.
Melissa:
31:54
Mhmm. And
Jam:
31:54
they seem way cool. Wouldn't be the best person to, like, judge it, but they were obviously hanging out, studying together. So Yeah. That says a lot.
Melissa:
32:02
Yeah. So that's probably it for me. Well, thanks for coming up here for meeting my students and coming up to my office to learn about the cutting edge of bad smell chemistry. And thanks to all of you listeners for tuning in.
Jam:
32:19
So Melissa and I have a lot ideas for topics of chemistry in everyday life, but we wanna hear from you. So if you have questions or ideas, you can reach out to us on Gmail, Twitter, Instagram, and Facebook at chem for your life. That's Kim, f o r, your life to share thoughts and ideas. If you enjoy this podcast, you can subscribe on your favorite podcast app. And if you really like it, you can write a review on Apple Podcasts.
Jam:
32:40
That helps us to be able to share chemistry with even more people. If you'd like to help us keep our show going and contribute to the cost of making it, Go to kodashfi.com/chem for your life, and donate the cost of a cup of coffee.
Melissa:
32:53
This episode of chemistry for your life Was created by Melissa Collini and Jim Robinson. References for this episode can be found in our show notes or on our website. Jim Robinson is our producer, and we'd like to give a special thanks to a Colini and s Flint who reviewed this episode.
01:57
Hey. I'm Melissa.
Jam:
01:58
And I'm Jam.
Melissa:
01:59
And I'm a chemist.
Jam:
02:00
And I'm not.
Melissa:
02:01
And welcome to chemistry for your life.
Jam:
02:03
The podcast that helps you understand the chemistry of your everyday life.
Melissa:
02:06
Are you ready to learn more about smells?
Jam:
02:09
I am so ready.
Melissa:
02:11
We're gonna talk about why something smells so strongly bad to us.
Jam:
02:16
Okay.
Melissa:
02:16
You're gonna tell it back to me, and then I'm gonna give you some fun smell facts as a bonus for your Proper explanation.
Jam:
02:25
Okay. So, basically, everything, all these fun facts are riding on me getting this right.
Melissa:
02:32
Just the 2 fun facts. Yeah.
Jam:
02:33
Okay.
Melissa:
02:34
At the end.
Jam:
02:34
Alright. Alright, folks. Be cheering me on. For all of our sake, we get to hear these cool fun facts if I get this right. So
Melissa:
02:43
Okay. So we talked about our olfactory receptors last time Uh-huh. That those are controlled by genetics. There are about 800 in humans. 400 of those seem to be active.
Melissa:
02:55
Okay. There's 1,000 in mice in case you're wondering.
Jam:
02:58
Woah. That are active?
Melissa:
03:00
I don't know if they're active. And about 10 no. And about 100 in monkeys, I think.
Jam:
03:09
What about dogs?
Melissa:
03:10
I don't know. Probably more.
Jam:
03:11
Yeah. Because they're, like, all about the nose.
Melissa:
03:13
I did read a book, About forensic science that said that the reasons that dogs could smell part of like, how dogs could smell so well and why they wrinkle up their face is they hold the smells in their wrinkles, and then they can sort of unfurl to get a little reminder what it smells like. And the reason their ears kind of are so long is so they can kick up the smells with their ears.
Jam:
03:38
I heard about the the ears thing only because One of my dogs is a beagle, and he's got long ears. And he's he's bred for that kinda deal for hunting.
Melissa:
03:47
And he can find smells. Oh, yeah. One time, he destroyed he didn't really destroy. One time, he made a significant material alteration to a backpack of mine in search of
Jam:
03:58
Yeah.
Melissa:
03:59
Empty Tupperware that had once contained food, but didn't anymore.
Jam:
04:02
Yeah. He, caused a wardrobe malfunction on your backpack there.
Melissa:
04:06
A 100%.
Jam:
04:07
Yeah. And that's a common thing. I mean, like, a lot of dogs can do that, but any sort of hound can is, like, even more smell Driven. Like, it's almost like
Melissa:
04:17
you're driving crazy. Inside a backpack. Inside a lunchbox. Yeah. In a closed Tupperware.
Jam:
04:23
Inside of a safe in the ocean, and he still got it.
Melissa:
04:29
But I kept using that backpack until it got doused in dichloromethane.
Jam:
04:32
Oh, okay. And that did he do that too?
Melissa:
04:35
That he was in the lab, and there was an accident.
Jam:
04:37
Yeah. Yeah. He yeah. He's a little clumsy.
Melissa:
04:40
Okay. So
Jam:
04:41
Without thumbs.
Melissa:
04:42
Different ones of those different receptors will detect for different things. Okay. Okay. One major class of smells Mhmm. That we detect for is a sulfur containing compound called thiols.
Jam:
04:59
Okay.
Melissa:
05:00
Thiols are also sometimes called Mercaptans Okay. Because they react with Mercury. They're Mercury capturers, so mercaptains. Mhmm.
Jam:
05:11
Like a mer like a mermaid or merman, but it's a captain.
Melissa:
05:15
Except a mercury captain.
Jam:
05:17
Got it.
Melissa:
05:17
Mercury cap Div taker.
Jam:
05:19
Okay.
Melissa:
05:20
So Mercaptans or thiols are interchangeable. People have heard those before. I think it's a fun name, Mercaptans. And now this is in response to a question that we asked were asked after our hair episode
Jam:
05:35
Mhmm.
Melissa:
05:35
From Joey h. Mhmm. The question was, why doesn't our hair smell bad like sulfur? In the class of sulfur compounds that we usually can detect so strongly Mhmm. Is actually sulfur bonded to a hydrogen.
Jam:
05:50
Okay.
Melissa:
05:51
That's a special functional group. Uh-huh. We talked about functional groups being an arrangement of atoms back in the very first episode that we talked about amino acids, the Maillard reaction. Mhmm. And that functional group is any carbon containing compound with a sulfur bonded to a hydrogen.
Melissa:
06:10
Okay. So those have the smell that we detect for. That functional group, I do not think is present in our hair.
Jam:
06:18
Okay.
Melissa:
06:19
It's Sulfur is bonded within the bigger system of the cysteine.
Jam:
06:23
Mhmm.
Melissa:
06:25
So that's answering Joey's question. Shout out, Joey. But we do detect for the thiol smell. Now what's interesting Uh-huh. Is thiols are very similar to alcohols.
Melissa:
06:38
Okay. Alcohols are a functional group with an oxygen bonded to a hydrogen.
Jam:
06:43
Okay.
Melissa:
06:44
So instead of a sulfur bonded to a hydrogen, it's an oxygen bonded to a hydrogen.
Jam:
06:48
Got it.
Melissa:
06:49
And sulfur and oxygen are in the same column on the periodic table. Uh-huh. And, usually, if you switch out those atoms that are in the same column, they will have very similar chemistry.
Jam:
06:59
Oh, interesting.
Melissa:
07:00
Because they have the same number of electrons around them. Mhmm. They are usually very similar, not exactly the same.
Jam:
07:06
Got it.
Melissa:
07:07
In this case this is amazing to me because I'm so used to alcohols and thiols reacting and acting Similarly, in chemical environments Uh-huh. We are 100,000,000 more times sensitive to Sulfur compounds, the thiols, then the alcohol compounds.
Jam:
07:30
Really?
Melissa:
07:30
With a very similar structure with very Similar chemistry.
Jam:
07:34
Uh-huh.
Melissa:
07:35
We are 1,000,000 more times sensitive to 1 than the other.
Jam:
07:40
What the heck?
Melissa:
07:41
Isn't that amazing?
Jam:
07:42
Yeah. A 1000000 times is a little excessive.
Melissa:
07:44
Not 1,000,000. 100,000,000.
Jam:
07:47
Oh my gosh. Couldn't it just been 10? Like, how why do we need it to be so high?
Melissa:
07:52
Well, it's because of survival.
Jam:
07:55
Oh, okay.
Melissa:
07:56
Those thiols of sulfur containing compounds are in rotten food, dead animals Mhmm. Poisonous gases, not all poisonous gases, but some.
Jam:
08:05
Yeah.
Melissa:
08:05
And even some carnivores, which would theoretically be our predators Uh-huh. Can sweat out and excrete Sulfur containing compounds in their sweat, so it's almost for safety.
Jam:
08:18
Woah. That's crazy.
Melissa:
08:20
Isn't it? Yeah. I, Literally, the next line I have written is, which is crazy.
Jam:
08:26
Did I ever tell you I think I did tell you this, but I don't think I told you on here. About when I posted a story about sulfur, like geothermal pools and stuff like that when we're in New Zealand. There's there's a specific
Melissa:
08:41
Yes.
Jam:
08:42
Town we're in called Rotorua, which seriously, no matter where you go in Rotorua, it Does smell like sulfur. They it's so much geothermal interesting. Yeah. So many geothermal pools and, like, steaming Pools and even just kind of steam coming out of the ground in different places, stuff like that, just so geothermal active everywhere Mhmm. That the entire Town smells like sulfur.
Melissa:
09:06
So a little bit like rotten eggs? Yes. It was a great smelling town.
Jam:
09:10
It was rough. But, like, obviously, the pools looked super cool.
Melissa:
09:13
And it had a
Jam:
09:13
super cool forest there too. So it's like, okay. It doesn't smell like I'm in a garbage dump, but yikes. Does it is it hard to stick around here? We didn't say that.
Jam:
09:22
We just We're like, let's hang out. Let's look at this stuff. We ate some food, which actually was okay because we were got inside, and it smelled more like the food. But Everywhere else we went smelled like sulfur. Interesting.
Jam:
09:34
So we're like, let's let's get out of here.
Melissa:
09:35
I wonder how those people's noses have changed and adapt to that Going on Yeah. The people who live there.
Jam:
09:40
They were new. It was a big touristy place because of all the things that you could see. So it was, like, plenty of people go there by choice And stay there. So I don't know, man.
Melissa:
09:50
That is fascinating.
Jam:
09:51
It's crazy.
Melissa:
09:52
Well, according to some chemist, They believe Mhmm. That there's an enhanced reactivity to these compounds in our olfactory sensors Mhmm. Because Our body has figured out to use the copper in our bodies to enhance the reaction to it.
Jam:
10:12
Oh.
Melissa:
10:13
Yes. So it was hard for me to understand in this paper that I was able to find if it was because The copper enhances the binding so more molecules are able to bind. Uh-huh. It's called a binding constant. So is there more molecules binding for the same concentration, or if it just somehow the copper makes the signal stronger without making the actual binding of the molecule stronger, but the presence of copper and I think there's not a ton known about this because it was a relatively recent paper.
Melissa:
10:46
The the presence of copper Mhmm. With Specific olfactory receptors will enhance the awareness of sulfur thiol compounds, and that's why we smell it so strongly. And I feel the author put it better than I can.
Jam:
11:03
Okay.
Melissa:
11:03
So I'm just gonna quote from this paper about Copper in olfactory reception.
Jam:
11:08
Okay. Sweet.
Melissa:
11:10
The absence of a metal effect in an extensive screening using, Just to paraphrase other olfactory receptors for ligands, including alcohols, amines, sulfides, Diols and carboxylic acid indicates the metal effect now present in both humans and mice may be a restricted phenomenon within an organism's olfactory system and may be specific to certain compounds where Sensitivity is of utmost importance. So translated, that means that the metal effect essentially is very rare And only used in instances where it is very, very important likely for survival, like in the case of thiols.
Jam:
11:57
Mhmm.
Melissa:
11:58
Isn't that amazing? Yeah. And this is in the presence of copper, which is naturally occurring in our body.
Jam:
12:06
That is so weird. What the heck? I know. So stinking weird.
Melissa:
12:13
So this paper just came out in 2016 Mhmm. And it gives a lot of information on how one specific olfactory receptor will respond specifically to thiol odorants with ionic copper to activate strongly. Mhmm. It doesn't give a lot of the mechanism that I can understand because it gets back into that physiological side, but it makes clear that alcohols are unreactive in this same olfactory receptor. It's pretty incredible.
Melissa:
12:42
And this again was in 2016, which is not that long ago. Yeah. So I would assume that a lot of Smells and what's going on with this is still being discovered. This is one of the first times that they could find copper's role in human olfaction. They said it hadn't been demonstrated before Mhmm.
Melissa:
13:01
This paper. So that's kind of a new thing that's recently come out that copper is something that plays a part in the activation of these olfactory receptors, but they are likely Part of the 100,000,000 fold improvement between regular old alcohols and Bios.
Jam:
13:23
It's so, so nuts. Isn't it? You already thought about? What? Well, I was just thinking like, why do I need to be that strong?
Jam:
13:31
But what if it's that sulfur okay. So you can make a robotic nose. Mhmm. It smells everything the same. Mhmm.
Jam:
13:41
Based on how much of the molecules are in the air.
Melissa:
13:44
Mhmm.
Jam:
13:44
So, like, if you got a cup of coffee right near it, it's gonna be smelling coffee. If you got one further away. Might be feeling lost. Whatever. Yeah.
Jam:
13:51
What if there's actually, like, not tons of the sulfur molecules in the air, but it's just that we're so good at smelling it that that's why it smells so strong.
Melissa:
14:04
Right.
Jam:
14:04
Like, what if there isn't a lot of it? It's just that we're like Like, oh my gosh. What is that smell? And it's like, there's a little bit
Melissa:
14:10
one of the possibilities.
Jam:
14:11
And our bodies are like, There's sulfur, and they Make us smell it really strong.
Melissa:
14:17
So that is definitely what's happening. There are less sulfur molecules in the air. We can detect them A 100000000 times easier.
Jam:
14:26
Yeah.
Melissa:
14:27
So if there was 1 sulfur molecule in a 100,000,000 alcohol Molecules, we would detect the sulfur containing thiol the same as the 100,000,000 alcohol molecules. Gosh. Crazy.
Jam:
14:42
Yes. Very crazy.
Melissa:
14:44
But the question is about the mechanism behind that Yeah. And how does it do that? Mhmm. Is it that The one binds more strongly somehow because of the copper, or what? What is the mechanism that's making that signal so much stronger.
Melissa:
15:01
Right. Right. Copper seems to play a role in the enhanced detection. Yeah. But from what I can find, we haven't elucidated that yet.
Jam:
15:08
Got it.
Melissa:
15:09
There are likely people right now who are doing research on this.
Jam:
15:14
Mhmm.
Melissa:
15:14
Because in the chemistry world, 2016, 2019 as a second paper on that would be a pretty quick turnaround.
Jam:
15:21
Yeah.
Melissa:
15:21
It
Jam:
15:22
and think about 2020.
Melissa:
15:23
Yeah. So that would be very quick. So things are still happening Yeah. For sure. So that's my guess as to where they're at with this.
Melissa:
15:33
So there's still research going on, and we're gonna learn more. So it's not as satisfying as some of the other topics, but that's because I'm talking to you about research that is going on right now.
Jam:
15:42
This very moment Mhmm. Someone or many people are chipping away at trying to figure this out.
Melissa:
15:48
Right.
Jam:
15:49
That's so crazy.
Melissa:
15:51
So that's a shorter one, but that's why We smell smells Yeah. The way that we do. Yeah. Thiols, bad smells. And I was gonna tell you some things that have Those thiols in them Uh-huh.
Melissa:
16:05
Rotten eggs Uh-huh. Durian
Jam:
16:07
Uh-huh.
Melissa:
16:08
Rotting food. Like, The other day, one of my roommates left chicken in the refrigerator for over a week. Smelled horrible. I wanted to die.
Jam:
16:17
That's so weird. A week is not that long.
Melissa:
16:20
It had gone bad over a week ago.
Jam:
16:22
Oh, got it. It was bad for a week. Okay. Got it.
Melissa:
16:24
Yeah. I
Jam:
16:24
was like, that's okay.
Melissa:
16:27
It was bad. Or And it was in a in a grocery bag. So I was like, what's in here? And I opened it.
Jam:
16:32
And I
Melissa:
16:32
was like, I'm gonna die.
Jam:
16:35
Also, Like we talked about 2 weeks ago, the chemicals for Permian Mhmm. That smell, like we talked about. Mhmm. It's interesting how that Went from that to this, and it wasn't like it's set on purpose?
Melissa:
16:48
Right. It's Ammonium Thioglacolate, I believe. And so thio is because there's a thiol
Jam:
16:55
Cash.
Melissa:
16:55
In that compound that they put on your hair. Fascinating. Right?
Jam:
17:01
This is way cool. Yeah. That's crazy.
Melissa:
17:04
So that's all I have for you. If you can explain that back to me, kind of a weird abstract one to explain Mhmm. Then I'll give you 2 fun facts about our noses and smelling.
Jam:
17:15
Okay. I'm gonna try.
Melissa:
17:17
Great. I believe in your ability.
Jam:
17:20
Everybody, Cheer me on from your respective cars and headphones, and
Melissa:
17:25
let's hope
Jam:
17:26
we all get these fun facts as a reward. Okay. So Bad smells. There's 2 types of main what is that? Chemicals or compounds or categories of Of stuff, thiol and alcohol?
Melissa:
17:42
Well, those are just 2 really similar things. Alcohols And thiols have really similar chemical properties, but for some reason, one interacts with the nose like, woah, and the other one doesn't. They're very similar chemically.
Jam:
17:56
They're worth comparing because they're similar similarly.
Melissa:
17:59
Yes. Like, if I dunked 1 in a reaction and the other in a reaction, they would act very similarly.
Jam:
18:03
Okay.
Melissa:
18:04
They have very similar properties chemically.
Jam:
18:07
Which is why their comparison is so interesting because when it comes to our noses, they're so different.
Melissa:
18:11
Yes. Which is baffling.
Jam:
18:13
So For instance, like the sulfury bad smells
Melissa:
18:17
are a
Jam:
18:17
lot of times thiols. Mhmm. And This recent information
Melissa:
18:24
Mhmm.
Jam:
18:25
From 2016, Says that copper, which is already just in our bodies, and we already have a a stockpile of it, I guess Mhmm. Helps us be able to crank up our ability to be sensitive to The smells of thiols and sulfury type of bad smells? Yes. Kind of like. My my thought would be like kinda like Wi Fi versus Ethernet.
Melissa:
18:58
Oh, okay.
Jam:
18:59
So Wi Fi, it's there. Even if you get a good signal, it's it's there, and you can connect and stuff like that. But as soon as you plug in Ethernet, You have a direct connection. Your Internet speed is gonna be way faster.
Melissa:
19:15
Yeah.
Jam:
19:16
Insanely faster. So you get a little copper in there. Not Totally certain, yeah, exactly what thing it's doing. But somehow, the copper just immediately the better connection or allows It to have be more sensitive or
Melissa:
19:31
Boost that signal.
Jam:
19:33
Something. Yeah. That just boosts the signal a lot, and it's not like there's More abundance. That's why I picked that. Yeah.
Jam:
19:39
It's not like you suddenly got more Internet because you switched Internet service provider or something like that. It's like you just take A different path. You're you're introducing something new.
Melissa:
19:50
Right.
Jam:
19:50
And it just makes the signal way stronger.
Melissa:
19:53
That is a great way to describe it.
Jam:
19:55
And so you get that copper in there, and then you can smell those bad smells way better. It's just so nice that we can do that now. So thanks, copper.
Melissa:
20:03
That is a really good description. Yeah. I mean, this one, I was worried because it's kind of abstract. It's Yeah. I don't have a lot of answers.
Melissa:
20:10
There are still a lot of questions. And those Thial chemists, copper nose chemist, if you're out there, please reach out to me. I'd love to have a conversation about how you would explain this to to us and give us more information in detail. Mhmm. But until then, this is what we have.
Melissa:
20:25
And a lot of science is this is what we know right now.
Jam:
20:28
So I
Melissa:
20:29
was a little worried, but you knocked it out of the park.
Jam:
20:31
So that means we get the reward. Right?
Melissa:
20:33
That means you get the reward. So I've got 2 fun facts for you.
Jam:
20:36
Okay.
Melissa:
20:36
1, why do some things Not smell.
Jam:
20:40
Yeah. Why don't they?
Melissa:
20:41
Yeah. Why don't they? It's a weird, you know, it's a weird thing that some don't smell. There's 2 reasons that I can think of.
Jam:
20:47
Okay.
Melissa:
20:48
1 is some things don't vaporize, really. Mhmm. Metals don't have a super strong smell Mhmm. Because it's hard for them to rise.
Jam:
20:55
Right.
Melissa:
20:56
Sometimes I think we get metal ions, and maybe we have some of that. But Mhmm. But metal is not gonna smell as strongly as, like, fresh baking bread.
Jam:
21:03
Right. Right.
Melissa:
21:05
So sometimes things just don't vape vaporize. Mhmm. Some things do vaporize, and we can't smell them.
Jam:
21:11
Okay.
Melissa:
21:12
We call those odorless. Mhmm. My suspicion is, although I was not able to confirm this Mhmm. That there's no olfactory receptors for those things to signal a smell.
Jam:
21:24
Bad.
Melissa:
21:24
Because I don't think I think the only thing that makes something odorless is that we can't smell it. Mhmm. But can we not smell it because it doesn't have a smell, or can we not smell it because we don't?
Jam:
21:34
Have the ability to understand it or, like Yes. Receive it.
Melissa:
21:39
So I was wondering if mice have one Thousand olfactory receptors. Mhmm. Can they smell things that we can't smell? Maybe carbon monoxide has a smell to them. Yeah.
Melissa:
21:50
So I was just thinking about that. Dude.
Jam:
21:52
Yeah.
Melissa:
21:52
That was a fun thing to stir in there.
Jam:
21:54
Mhmm. I like that.
Melissa:
21:55
Kinda like, are there colors that we can't see?
Jam:
21:58
Yeah. The whole mantis strip thing we talked about. Exactly. Whatever that whenever that was for Radiolab. Yeah.
Jam:
22:04
That's crazy. It would make sense that that'd be the case.
Melissa:
22:06
You can
Jam:
22:06
have more receptors. Be sensitive to more things because surely maybe you can make that argument, like, the hound dog thing. Like, maybe they have more and they can smell more. So, like, That's why they can trace a person.
Melissa:
22:19
Right.
Jam:
22:20
It's like they can smell all these things that we can't Yeah. That we think they'll have a smell.
Melissa:
22:24
Interesting. Right?
Jam:
22:25
Yeah. That's crazy.
Melissa:
22:27
The other thing Mhmm. Is not all thiols smell bad to us.
Jam:
22:32
Uh-huh. It
Melissa:
22:33
could be the dosage at which they start to smell bad. I Couldn't also find a ton of information on this.
Jam:
22:39
Mhmm.
Melissa:
22:39
But there are thiols in Citrus fruit.
Jam:
22:45
Mhmm.
Melissa:
22:45
Like grapefruit.
Jam:
22:47
Mhmm.
Melissa:
22:47
There are thiols present in that, but it smells good to us. Uh-huh. And they tested to see if it was above or below human detection limits, and it is above the levels of human detection limits in fresh squeezed grape Fruit juice or orange juice. There are thiol vapors present.
Jam:
23:08
That's so weird.
Melissa:
23:09
But somehow it combines with all the other things going on That it doesn't smell like rotten next to us.
Jam:
23:15
Yeah. Yeah. I I would even have thought that they'll be, like, on totally different spectrums of stuff chemically with the smells. Like, I would have just thought, you know, sweet, citrusy, kinda tangy smells over here.
Melissa:
23:30
Right.
Jam:
23:31
Horrible sulfur y smell over here. I just not would have would have not thought they have anything in common at all.
Melissa:
23:37
Yeah. It was super interesting. There was a whole long, long List. There's a paper that just basically took every compound and identified every single molecular compound Mhmm. Molecular present in grapefruit and citrus fruits.
Melissa:
23:54
And There is a special thiol that they call the grapefruit thiol, but there's also, I think, hydrogen sulfide gas was one of the things that was present, which is what makes rotten eggs smell bad. Man. Isn't that weird? Yeah. So I thought those were 2 fun, weird facts that don't take a or need a lot of explanation, but are just Interesting.
Jam:
24:15
That is really interesting.
Melissa:
24:16
So there you go.
Jam:
24:17
Wow.
Melissa:
24:18
That's the chemistry of smells.
Jam:
24:19
The mystery and the craziness of Smells continues. We learn a little bit, but we're also having more questions as we go.
Melissa:
24:27
Yeah. And smells that work in 1991. It was one of the last Ones of our senses to be fully elucidated or to be again being elucidated. Yeah. So I thought that was interesting too.
Melissa:
24:39
I learned a lot about smells. It was really fun preparing for this episode, but I think I still have a lot of questions. And I'm hopeful that I will learn more And maybe even be able to meet some of the people doing this work so that I can teach you guys more.
Jam:
24:54
That'd be awesome. I'd love that.
Melissa:
24:55
So that's all for the chemistry. Let's move into talking some about our weeks.
Jam:
25:00
Deal. So I had a good week. I've been Burning the midnight oil.
Melissa:
25:06
Oh, have you been?
Jam:
25:07
Working hard.
Melissa:
25:08
Working hard or hardly working?
Jam:
25:11
It you could call it either. I've been trying to catch up on movies.
Melissa:
25:16
Oh, interesting. Okay.
Jam:
25:19
The Oscars are coming up.
Melissa:
25:21
Well, yeah, because you're gonna have a child tune, and Mhmm. Your brain's not gonna do very well Yep. When it's that sleep deprived to actually be able to Take in the movies.
Jam:
25:30
Yeah. I'm I'm not sure how many years more I can try to keep up with the Oscars deal. And I don't like, you know, keep up with every single category. But I always use the best picture nominee list as a list of ones that I'll see. And there's many times that really good movies are not in that list, so it's not perfect at Aw.
Jam:
25:47
It's pretty flawed sometimes. And some years has been super flawed, head scratchingly flawed.
Melissa:
25:53
Head scratchingly flawed.
Jam:
25:55
So but this year, I think it's pretty good. And Okay.
Melissa:
25:58
So I've
Jam:
25:58
been trying to catch up on watching those movies.
Melissa:
26:00
I know nothing about movies.
Jam:
26:02
So Okay. Well, here's a list. I'll tell you which ones I've seen and in the order to fight
Melissa:
26:05
that. Okay.
Jam:
26:06
So I'm ready. The first one I saw was Once Upon a Time in Hollywood. It came out
Melissa:
26:09
Oh, I did see that one.
Jam:
26:10
Fall, I think, fall. Summer. Summer? Was it really? Yeah.
Jam:
26:13
You're right.
Melissa:
26:13
It was when I just moved in with my new roommates.
Jam:
26:16
So Summer, I saw that one. And then I saw Jojo Rabbit, I think in, like, November sometime? Mhmm. And those were the only ones I had seen on this list. And then I haven't
Melissa:
26:27
been told to see Jojo Rabbit, but I have not been able to do so.
Jam:
26:30
I think you'd like it.
Melissa:
26:31
Okay.
Jam:
26:32
It's there's a little bit of everything in there in a surprising way. It's funny and irreverent and also then, like, Really, really critical and thought provoking, and then also sad.
Melissa:
26:43
Now but I hate Wes Anderson, and I get the feeling it might be like Wes Anderson movies.
Jam:
26:48
I don't I would not say that it's like that.
Melissa:
26:51
Okay. Alright. I trust you.
Jam:
26:52
It just I think partly because it takes place in such a real scenario even though there's a lot of, like, Fictionalized elements to it. It's based on a real book. All of Sanderson's stuff for the most part is, like, totally fiction, his own universe kinda deal. It's like this is Hitler youth, Nazi stuff going on.
Melissa:
27:09
Okay.
Jam:
27:10
Saw that one in November. And then In the last 2 weeks or maybe I should say, like, 3 based on when this one comes out, this episode, I've seen, Little Women.
Melissa:
27:22
How was that? I really wanna see that one.
Jam:
27:25
Super good. Haven't not watched the old ones. So and I don't care to see them. I'm not I'm
Melissa:
27:28
not gonna watch you now. Book?
Jam:
27:29
Nope. But I would read the book. Marriage Story, very sad. Very good.
Melissa:
27:35
That was on Netflix right now.
Jam:
27:37
Yes. It is. Go watch it now. And I want you alone. Not gonna give a review of all these.
Jam:
27:43
And then I saw, 1917 and saw a joker. Actually, I saw a joker before, All those. And then I'm almost with the Irishman. I've had to split into 3 sessions because it's, like, 3 and a stinking half hours long.
Melissa:
27:56
Wow. That's a very, Very long.
Jam:
27:59
It's the one I was looking forward to watching the least, and I've been surprised by it the most because I was so Thinking I would hate it and thinking that Yeah. I'd be waiting for it to be over.
Melissa:
28:08
So below expectations often leads to being present pleasantly surprised.
Jam:
28:12
It really does. So just think all these movies are gonna suck and then go see them all. Okay. But the accurate is better than I expected, and, break it up into 3 parts. You might feel the same way.
Jam:
28:21
The only ones I'd have to see are Parasite and Ford versus Ferrari. So close. And then it makes it really fun to watch the Oscars and try to see which one's gonna win because you feel pretty informed, at least, about the main ones.
Melissa:
28:37
And your degree is in film. So this, in a lot of ways, is is, like, an exercise in your professional opinion and and critique and skills.
Jam:
28:47
Yes. And it is really fun. I mean, there's so many movies that come out every year. It is fun to be kinda given a list of, like, here's some really highly regarded ones from this year. Mhmm.
Jam:
28:56
Go check these out. There's also a lot of other really good movies that came out, but it's kinda cool to see this and then try to predict which thing is gonna win or root for 1 that you really want to win.
Melissa:
29:06
Yeah. I think it's hard to imagine what that would look like in the chemistry world. But if there was one of those in my profession, I would really
Jam:
29:12
Yeah.
Melissa:
29:12
I would enjoy something like that. Okay. Review all these things, like Presentations or something from some of these renowned maybe Yeah. The Nobel Peace Prize.
Jam:
29:20
But Yeah.
Melissa:
29:21
You know, it's hard to know all the research that goes on in the world.
Jam:
29:23
So
Melissa:
29:24
That is really cool. I I could see how that, especially given your field, would be one of the things you look forward to Every year.
Jam:
29:31
Yes. And a couple years ago, the movie I was really cheering for as kind of an underdog did win, and it was such a cool year that have it's been, fun to to be as into the Oscars since then. But yeah. So that's been my week and last couple weeks.
Melissa:
29:47
Would you mind telling me what the movie that you really hoped Would win that did win was?
Jam:
29:51
It was Moonlight. Oh. And it beat La La Land, and it was a whole deal because the envelope accidentally got switched.
Melissa:
29:57
Did you
Jam:
29:57
read that?
Melissa:
29:57
Mhmm. And there was a very interesting, I think it was Radial Lab about, human error and oh, no. I think it was 99% invisible. Mhmm. It's about human error and poor design and how that envelope could have been designed
Jam:
30:12
Fox did meant to. Yeah.
Melissa:
30:14
Much better
Jam:
30:15
Yep. Mhmm.
Melissa:
30:16
To avoid the human error. And the fact that they didn't Anticipate the human error is ridiculous.
Jam:
30:21
Yep. So Moonlite won, and I was cheering for it from the very beginning. And it really deserved to win, for sure.
Melissa:
30:27
Wow. That's so cool. I haven't seen moonlight or la la land.
Jam:
30:30
Definitely seen moonlight. What about you? What's been going on this week for you?
Melissa:
30:34
One thing that I've been notice noticing and really appreciating lately is my students. And I talked about this some at the end of last semester, but
Jam:
30:42
There
Melissa:
30:43
are just such a bright spot in my days weeks where they will hang out in the area outside my office, and they Have formed a there's a kind of a core group that's formed a study group, and anytime anyone else comes around and asks questions, they're happy to help. It's just really a nice, Inspiring thing to see in students who are struggling in a class that can be very hard. And so It's just really an enjoyable part of my of my week and semester in life, really, where I get to see them be kind to one another, and I've gotten to grow to know them and know about their lives and enjoy their kind of unlikely friendships with one another. And So no matter else no matter what else is kind of going on in my life at this time, like, if I'm stressed or I've got school or whatever, when I'm working with them, all the things I have to do leave my mind, and I just am able to zoom in and enjoy Seeing them learn and grow and help each other. So that's been something that I've really, really enjoyed over the last several, Really several months because even into last semester.
Jam:
31:50
That's awesome. I even met a few of those guys talking about today.
Melissa:
31:54
Mhmm. And
Jam:
31:54
they seem way cool. Wouldn't be the best person to, like, judge it, but they were obviously hanging out, studying together. So Yeah. That says a lot.
Melissa:
32:02
Yeah. So that's probably it for me. Well, thanks for coming up here for meeting my students and coming up to my office to learn about the cutting edge of bad smell chemistry. And thanks to all of you listeners for tuning in.
Jam:
32:19
So Melissa and I have a lot ideas for topics of chemistry in everyday life, but we wanna hear from you. So if you have questions or ideas, you can reach out to us on Gmail, Twitter, Instagram, and Facebook at chem for your life. That's Kim, f o r, your life to share thoughts and ideas. If you enjoy this podcast, you can subscribe on your favorite podcast app. And if you really like it, you can write a review on Apple Podcasts.
Jam:
32:40
That helps us to be able to share chemistry with even more people. If you'd like to help us keep our show going and contribute to the cost of making it, Go to kodashfi.com/chem for your life, and donate the cost of a cup of coffee.
Melissa:
32:53
This episode of chemistry for your life Was created by Melissa Collini and Jim Robinson. References for this episode can be found in our show notes or on our website. Jim Robinson is our producer, and we'd like to give a special thanks to a Colini and s Flint who reviewed this episode.
