A (2:13)

Well, you might be surprised. What did you think of the actual meeting itself? So, for those of you who aren't aware, Perry and I intended and I attended the Society of Cosmetic Chemists Annual Scientific Symposium, which took place in New York City. This year. Next year will be in Los Angeles and essentially there are some scientific talks by people from all over the industry, poster presentations, et cetera. And we attended some of the talks together. We got inaugurated as Perry the vice president, me as the vice president elect. That's right, the National Society of Cosmetic Chemists. So it was a lot of fun.

B (2:51)

It was. So overall the meeting was pretty good. I mean, it's kind of late in the year. I hope we could make it a little early in the year, which we're going to do next year, so. Because it's a little too close to Christmas. Although New York at Christmas time is pretty cool. They have all the decorations and such.

A (3:06)

Yeah. And snow.

B (3:07)

But as the meeting goes. And snow. That's right. You know, I was joggling in Central park and I slipped and fell. Fortunately, I didn't hurt myself too bad, but I did lose a bean bag and like I was looking around for it and some nice New Yorker. There are nice New Yorkers. She pointed down the. Down the road where my beanbag had. Had rolled all the way down. So I saved it.

A (3:35)

Oh, good.

B (3:36)

Well, I went to the. I went to some of the hair talks and.

A (3:40)

As did I. Yeah, you know, they.

B (3:42)

Had some interesting topics they were covering.

A (3:45)

Underwhelming, in my opinion.

B (3:47)

Yeah, I mean, the topics were good. It's just the presentations felt a little too marketing ish to me. You know, they were light on the science and the. Heavy on the hype, which I don't like exactly.

A (3:58)

Well, the last Talk was the CEO and co founder of K18. And at first you might think, oh, wow, we're actually going to hear about peptide design and all the things that they did. And it basically was how amazing K18 was. And so I was just like, you know, you talk about this peptide and how it sticks to hair, but how well does it stick to hair? There's a specific scientific metric for like, how well proteins bind. I studied proteins in graduate school, so I was very keen on this topic. And he basically was like, oh, you wouldn't need to know that. Another gentleman who also said. Spoke about novel peptide design for hair said, yeah, that's not something that's important because hair just keeps getting damaged. And the K18 guy agreed. And I was like, which basically tells me you either didn't do the testing or the data's not impressive.

B (4:51)

Yeah, I am in agreement with that. So those were a little disappointing. I actually moderated the future technologies 1 and there were some interesting things there about, especially this one that was this new type of ink, which is organically derived ink, which could make for interesting colorants in the future. It's challenging because the industry is highly regulated when it comes to colorants. But he was deriving colors from algae, which sounded kind of interesting.

A (5:25)

Yeah, it was Living Ink technologies and I think it could be interesting. But I also think they're limited to BlackBerry because I was reviewing their patent while the talk was going on. And essentially to make the color, it relies on pyrolysis, which you know is fire. Right. So it involves high heat and then complexing with the metal ligand. And I think through this method you can pretty much just make black. And pretty much that's all they've made.

B (5:55)

Right? Right. Well, you know, maybe in the future different colors that come out, but if it's just left with black, I mean, I guess that is for eyelashes and that sort of stuff.

A (6:05)

Yeah, it could be cool.

B (6:07)

Could be a new mascara color. Then there was also that talk about these. Look for this one to be marketed in the future. But the small RNA based actives. I think we're gonna start hearing about RNA based actives in the future. Although I have to wonder, the whole Covid RNA vaccine and such was in people's mind. I wonder if this technology might get confused with that and people would be afraid of it.

A (6:36)

I think when it comes to RNA and DNA fragmentation, like other really small fragments, the challenge is these are really small amounts of base pairs that we're talking about. So it's possible that if they did penetrate, there could be some penetration. And I think it's hard to explain to the consumer that no, this like DNA sequence is like very particular or this RNA sequence is very specific. And I think it is hard to explain. So it'll be interesting to see how it plays out. But I agree there may be some challenge to adoption because even in the audience people address questions similar to what you just brought up with some of the vaccine mechanisms. And I was like, oh, I didn't even go there. But apparently some people are, you know.

B (7:27)

It'S interesting that how non marketing savvy some scientists are now. We went, we had a guy who was presenting, he was way too far in the marketing side. But there are some like sciencey people who don't think of consumers. I was watching, I was reviewing a poster and the girl was explaining how she made nanoparticle something or others, which I think the technology is great. But people are afraid of nanoparticles. They don't want to know about that. Right. And I Pointed that out to her and she didn't even know that was even a thing.

A (8:04)

Well, what's challenging about the student presentations, in my opinion, is that they are not really like, I'm a deep reader. You're a deep reader. If I'm curious about a topic, I'm pulling literature. And I was like this in grad school as well. I'm trying to consume as much information as possible. And there was a girl presenting nail polish research, and there were like, fundamental things she did not even know about nail polish. And I was like, didn't you, like, just Google like nail polish science that kind of would have told you the answer. And so I'm just a little surprised about how little industry context there is in academia. But then again, I'm also not surprised.

B (8:44)

Yeah, I mean, and some students are better than other students. So, you know, that's why we let everyone in. And then there's that whole judging thing and such. But I just appreciate that people get up there and try to present. And, you know, overall, I think people are sincere. But you're right, there is certainly a disconnect between industry and a lot of academia, for sure.

A (9:07)

Well, it was great to see you at the show.

B (9:09)

Yes, you too. And actually we did record a little greeting message. I'll put that up on Patreon.

A (9:15)

Oh, nice. Well, let's head over to beauty news. Our first news bit takes us to talc corner. Kind of it's not about talc in the lawsuits, but the FDA did withdraw a talc ruling recently.

B (9:34)

It turned out that the FDA was requiring manufacturers to test for asbestos in talc. And that was related to the J and J lawsuits over the bunch of years. And so there was this requirement. And so now the fda, I guess they're being less stringent and they're saying, let's get. There's good, good cause to withdraw the proposed rule at this time.

A (10:03)

Well, I think the challenge is it's not that they're trying to be less restrictive. Yeah, I feel like there were a lot of things that were missing from the Aspect Festos ruling. And in fact, I had kind of wrote about it in a happy magazine article a couple years ago. And a gentleman who's well versed in the history of talc testing in the industry told me the FDA kind of had it wrong in terms of methodology. It turns out, like, the methodology is really important. And so my interpretation of the FDA stepping back and kind of withdrawing the final opinion is that they actually want to do a more, I guess, like, closer look at some of the methodologies that are there. I don't think they're saying, you know, asbestos and talc isn't a problem, because it is. But I think the way the prior guidance was written is not very good.

B (10:56)

And I think ultimately it still leaves the responsibility of safety in the hands of where it has always been. And that's with the brands. And so it behooves them to make sure that they're not selling products that are unsafe. So, you know, they're going to do the most rigorous tests and maybe reporting into the government by following some antiquated testing that they were requiring before, maybe the new testing is actually better.

A (11:24)

Exactly. So, I mean, I guess more to come. I don't want to, you know, make judgments. I don't really know their full reasoning, but I do know that being part of regulatory groups that were looking at the pressure prior guidance, it wasn't. Wasn't very robust. So hopefully that's their intention moving forward.

B (11:42)

And, you know, the industry really is kind of getting away from talc, not necessarily for safety reasons, but for reputation reasons because, you know, consumers are afraid of it. You hear all this J and J stuff about baby powder and, you know, companies just will move away if they have other options. And for talc, there are some other options.

A (12:01)

Exactly. Well, I saw an article that was from a study in Singapore. They, the study group, meaning, looked at different conditioning agents found in hair conditioners, and they found that behem trimonium chloride is the best conditioner, and they used electrokinetics to study this. So basically what that means is they put electrical impulses through conditioning agents that had been applied to hair, and they figured out that the more of an electrical conductance through the hair conditioner, the more that it was willing to stick to the hair. And I found this interesting because I think their commentary is in the eye of the beholder.

B (12:47)

Yeah, like how do you determine something's the best as far as conditioning go? I guess they specifically looked at, like, wet combing and feel, maybe.

A (12:59)

No, basically it was how much electrical movement happened through the hair conditioner. And basically what they found is behem trimonium chloride and behem trimonium methyl sulfate lasted the longest on the hair, and stearalkonium chloride didn't really stick too well, primarily because of stearic hindrance. And cetrimonium chloride also did not do well because it stuck easily to the hair, but it didn't stay on the hair for a very long time. And so, again, I think it's a really simplistic opinion to make a about a really complex matter because it depends on your hair type. It depends on whether you're evaluating the hair wet, whether you're evaluating the hair dry, and a lot based on tactile touch. So anyway, it was kind of interesting, but also I think kind of a bold statement when at the end of the day, it just matters about the consumer perception.

B (13:57)

And as far as consumers go, how you perceive conditioning is going to depend more on how it works on your hair versus what we can prove in the lab. So for some people, you know, behemonium chloride might be great. Other people who enjoyed VO5 all their lives, maybe we'll go with sterile conium chloride.

A (14:20)

You know, I'm not a big fan of sterolconium chloride. It feels a little waxy on the hair.

B (14:25)

Yeah, it's. Well, you know, back in the 90s, people like that waxiness.

A (14:28)

It reminds me of the 90s. Exactly.

B (14:32)

Well, you know, that's when we switched. When I started on VO5, it was all based on C Tramonium chloride. Wow. Yeah. And then we made our big switch to stearalkonium chloride because consumers liked it better.

A (14:46)

You guys were so novel back then.

B (14:49)

You know, when the formula only costs you 10 cents a bottle, you don't have a lot to work with.

A (14:56)

Oh my goodness.

B (14:58)

Another story I saw everybody's all up in a buzz about is that the FDA has endorsed a new sunscreen, this Bemotrizinol, which is, they're pushing it for modernize OTC sunscreen standards. So they propose that they're going to permit this active ingredient for OTCs. So bemotrizenol, which is a UV filter, it's already used internationally and provides broad spectrum protection against both UVA and UVB rays. And so the FDA decided it. The absorption through the skin was minimal. So they are confident in saying that you can use this in sunscreens going in the future. I will say there has to be like a 60 day commentary thing. And so this is not a done deal, but it's as close to as done deal as you can get with these kinds of ingredients.

A (15:56)

Well, especially since the FDA endorsed it. Right. And they're asking for the core of public opinion, which usually means the private beauty sector, to chime in and say, hey, are there any red flags before we, you know, sign and push go. And I'm part of a couple industry advocacy groups and we're definitely supporting the FDA to get this new sunscreen filter. And we actually were approached by a representative from the raw material company who did all the testing. DSM is the name of the company. And they are going to sit down with Perry and I and tell us about some of the testing that they did. Now it's really important to know one thing that the reality is all sunscreen actives have been animal tested. And so you have to come to grips with that, right?

B (16:46)

That is true. This will open up a new formulation pathway, new formulation feels and aesthetics that we haven't been able to get in the United States since then. This is a new UVA blocker and right now in the United States we only have zinc oxide and avobenzone as the only UVA blockers. So this opens up a whole new avenue.

A (17:13)

I'm excited.

B (17:14)

Yeah, it'll be interesting. I haven't. Have you felt a formula with this in it? I haven't.

A (17:19)

I feel like I've used one in the eu. I feel like this is in many European formulas and honestly Perry, I can't tell a difference. You know, it's a, you know, a lot of the aesthetics depend on, you know, the emulsion and the other materials found in the SPF active. And these SPF actives, because of their molecular structure, they're just intrinsically greasy feeling. And so honestly it kind of feels like. And plus it's used with other things so it's really hard to get a feel for its distinct feel.

B (17:53)

It'll be interesting to see how the anti chemical sunscreen people are. Cuz this is not, this is not a mineral sunscreen. This is, you know, an organic chemical.

A (18:04)

They may not be excited.

B (18:06)

Right?

A (18:07)

As excited as we are, don't look.

B (18:08)

For this in your latest clean beauty product.

A (18:12)

Let's head over to some beauty questions.

B (18:19)

Our first question comes to us from B. Hello, beauty brains. I thought a shampoo with low ph also helps preserve color since it doesn't open the hair cuticle that much. But would love to hear is this really a thing? Thanks. Well, ph with low ph shampoos, I don't know why consumers got obsessed with ph and shampoos. You know, it's ph for a shampoo. A ph is all about manufacturing procedures and stuff. And it tells you something as far as it works. When you put a shampoo on your head, you dilute it with pH7 water. And so whether it was, you know, a 4, a 6 or a 5, when it's on your head, it's gonna be 7.

A (19:03)

Well, kind of. I mean the reality is most shampoos are in a ph range of on the super lowest end. 4.5 right to 6.5 to really max 7. Unless you're a clarifying shampoo or you're trying to demineralize the hair, you're not going to be too high. So the reality is most shampoos are in the same PH range as a face wash. And when a brand is saying, oh, we have a low PH system, I would love for them to define what that is. Because you can't go too low of a PH on a surfactant system. Otherwise you start to break down the surfactants that are present present in the product. And so the PH is never really that low. And at the end of the day, it's about how much surfactant is present in the shampoo, what types of surfactants are present. Some of them are better cleansers than others, how water soluble the system is. Those are the types of things that are going to pull the color out of your hair. So I don't really buy the whole low PH story. Now, if you were going to use A, a pH8 clarifying shampoo to get metal ions out of the hair, that's a different story. But you wouldn't be using that as a daily shampoo. The most important thing is that you look for color preservation claims on the packaging.

B (20:23)

I also don't think the PH has much to do with whether you're opening the cuticle or not. Once the hair gets wet, it swells up and the cuticle is going to open up as much as the cuticle opens up.

A (20:35)

Exactly. I also agree with that. All right, well, our next question comes to us from Ryan. How well does polypodium leukotomose work for sun protection and antioxidant supplementation? What does the SPF factor equal to if you take 240 to 500 milligrams, should it be taken year round or can you just take it during the summer? I'm not sure how long you need to take to get benefits of. Of protection. Anything other that you can add about this extract? I'm trying to research if it's worth adding to my supplements. Thank you. Love your podcast. I listened for years, Ryan.

B (21:12)

Oh, well, if Ryan's listened to years, he knows what I think about supplements, which is not much.

A (21:19)

Well, additionally, I think the supplements that are advertising sun protection are a really tough sell, in my opinion, because they aren't really proven to prevent burning per se. Maybe they reduce inflammation, maybe they help repair DNA at best. But I think it's really hard to say that there's an SPF factor equivalence to taking an oral supplement. Everyone's body metabolizes these differently.

B (21:47)

Well, Polypodium leukotomas, it's one of those ingredients. Right. There's some real science here, but it's mostly marketing exaggeration. So it's. It's a fern extract that is rich in polyphenols. So it has furylic acid in it. Yeah, antioxidants and such. And so when you take it orally, you know, you're going to get sort of system antioxidants effects for the stuff that doesn't get out of your stomach or that does get out of your stomach. You know, mostly to me, once it gets in your stomach, it gets broken down, but you know, some of it might get into the rest of your body. So if this does. So there's not really any valid SPF equivalent for an oral product because SPF is a. It's a specific measurement where you expose the skin to UV radiation and you see how long it takes to burn and you expose the skin to UV radiation when it's coated with the sunscreen and you see how much longer it takes to burn. And so it just doesn't really work for a supplement because you can't do that before and you can't do that side by side testing. So there's no real SPF value that you can give to a supplement like this in the same way you do to a cream.

A (23:12)

Also, I reiterated this a few podcasts episodes ago. I just get really nervous about taking too many plant extract supplements. And maybe I didn't specify plant extract supplements, but your liver does have to process all of these things.

B (23:31)

Right.

A (23:31)

And you know, the supplement company, they're maybe not necessarily doing all the tox studies that would be required. Maybe they are, I don't know. But I just get a little nervous because we don't know how your liver is impacted by any of this. So I don't know. I think you get better sun protection from topical spf. And then it sounds like you already have some supplements. I would just bone up on some antioxidants, you know, that you're already taking.

B (24:00)

Yeah, I mean, I personally, if the choice is between a supplement and sunscreen, I mean, use your topical sunscreen or stay out of the sun as much. Now, as far as how long does it take to work? You know, antioxidants effects with this stuff is supposed to be appear within days and not months. And so if you're going to rely on this and you kind of believe It. I mean, I don't. But if you do, it's going to take a few days to kick in. So you have to start taking it, you know, maybe a week before you want to start to see some of the effects, if there are any effects.

A (24:37)

And it definitely wouldn't replace spf, you would still need to wear it. So I'm not sure what the added value would be or if you'd be able to tell a difference.

B (24:45)

Right, so. So that's that. Hope that helps there, Ryan.

A (24:50)

All right, our next question comes to us from Diane.

B (24:53)

Diane says, can you please discuss the effects of hard water on hair color and some products that help besides a shower water filter? Thanks. People are worried about hard water in their products. And I've never exactly understood this is hard water found a lot of places.

A (25:11)

I think people do have hard water. Maybe not. I mean, depending if you're in a city, I think it's treated pretty well. But even then, I think you can have different varying levels of total solids found in water, which are typically measured as calcium and magnesium. Where we lived in Los Angeles had a really high solids content. It was, I would say, almost borderline. Someone should be calling the epa.

B (25:35)

Oh, really?

A (25:36)

Nonetheless, yeah, we used a filtration system at work for all of our water. But a lot of people do use well water or they have water supplies that aren't really great. But the problem is just because you have hard water, your water could be really hard or it could be mildly hard. And if your hair is going to be susceptible to hard water, it doesn't have to be extreme in order for your hair to feel an impact, at least from calcium and magnesium ions. And it's only a problem if you bleach your hair pretty much. So basically chemically damage it, create a lot of negatively charged sites on the hair fiber, then it's a problem. But if you have pretty healthy hair, hard water is less of a problem. But nonetheless, everyone's worried about it. And I don't know of any effects that if you were to have your hair colored at a salon and then you go too hard water and wash your hair. I don't know of anything in literature where the ions impact the dye molecules, but I do know that if your hair uptakes these molecules, like for example, lead, iron, copper, your hair can shift color should it accumulate enough of them. So you'd have to have like really hard water for this to be an issue. Not just catch calcium and magnesium but other stuff present, and then it can make it a little Dull.

B (26:57)

I also imagine that if you're using hard water and it absorbs a lot of these ions, it's going to affect the color that you get when you get your hair colored.

A (27:08)

It would affect future coloring services. Yeah, but not like the color you have in your hair today so much other than like the same stuff that it would do if you didn't color your hair. But nonetheless, it is important to remove some of these metals from your hair. Not calcium and magnesium, because the next time you rinse your hair, you're going to get exposed to them and then they'll just reattach to your hair anyway. I'm talking the coppers, leads and irons that I mentioned. And so to do this, I wouldn't recommend a daily product. I actually would recommend kind of like a treatment, maybe weekly, if you have pretty hard water and care about it, or maybe even monthly or just before you go get your hair colored the next time I would recommend like a Malibu C or l' Oreal Professional. It's a salon brand. They make a series, a product series called Metal Detox. And these essentially pull metal ions out of the hair that you don't want in there to help reduce damage the next time you get your hair colored.

B (28:05)

They have high levels of chelating agents in it, Right?

A (28:08)

Exactly. But here's where you do have to be careful about not overusing these product types, as I mentioned in a previous question, is that some of them, especially the cleansers, have a little bit higher of a ph. And while PH doesn't necessarily strip your hair of more color, it can be typically these systems are very detergent because the goal is you want to like strip the hair and clarify it. And so for that reason, I probably would say not to overuse the hard water products unless you, a brand like l', Oreal, who does a lot of robust clinical testing, advertise it as a daily use product for metal treatment on hair.

B (28:46)

Yeah. Now, I know hard water has always been a problem for soap. That's where you get the soap scum. And it interacts with the detergents for the shampoos. For modern shampoos, though, they function pretty well in hard water. And the detergents don't actually interact with the ions very much.

A (29:06)

No, not as much. But if you are using a product maybe that has like these free fatty acids and, you know, maybe they run into a little alkali in the product, then they're running into these magnesium ions. You could get like a little magnesium stearate or something like that. Which I think is what soap scum is.

B (29:25)

Right, Right.

A (29:27)

Not too much. But, you know, I guess in theory it could happen.

B (29:31)

I mean, I guess there's some residuals in all of the surfactants, too. And so there are some of those fatty acids. Even if the ingredient doesn't call that out on the label, there is some residuals there.

A (29:43)

That's also true, but I don't know if it's something to lose sleep over.

B (29:48)

Yeah, I don't think so either.

A (29:51)

All right, our next question is from Ethan. I've seen studies suggesting that topical tretinoin may be linked to intracranial hypertension. How significant is this risk in practical terms, intracranial hypertension? Do you know what this is, Perry?

B (30:09)

It's a condition where pressure inside the skull increases, and that's without having a tumor or something. And there's no other obvious cause where people get headaches and maybe visual disturbances and even some, in severe cases, vision loss. So it does not sound good. Do you have experience with this?

A (30:32)

I actually was checked for this back when I used to get headaches every day and several migraines a week, and it actually ended up just being blood clots going to my brain. But they did check for this to make sure I didn't have any issues. So I was clear.

B (30:47)

Well, as far as the topical stuff, the short answer is that for the vast majority of people using topical tretinoin as directed, the risk for intracranial hypertension is extremely low. I mean, it exists more as a theoretical and rare clinical observation than a practical problem that, you know, people, regular people, need to worry about.

A (31:11)

So why would Ethan think this? Well, of course, Ethan didn't come up with it on his own. He mentioned he saw studies.

B (31:19)

Yeah, yeah, he did include a couple of links and we include them, but there is actually an issue with retinoids. So systemic retinoids, especially oral isotretinoin and vitamin A overdoses, they actually have a pretty well established risk factors to intracranial hypertension. So it's not really controversial. So if you get enough buildup of retinoids in your blood, then that can have an effect on your cerebrospinal fluids, and that can possibly have an impact on this intracranial hypertension. So at least theoretically, there is a reasonable case you can make for why that might be a problem.

A (32:03)

So the initial thing that you mentioned is this is oral, right?

B (32:08)

His question was, do you have to worry about the topical stuff?

A (32:12)

Right. But some of the initial papers were about taking it orally.

B (32:16)

Yeah, yeah. No, all of the concern of it, I think, comes from taking it orally.

A (32:20)

Okay, so now the question is, does it happen topically?

B (32:25)

Right. Exactly. Now, the papers that he linked were a couple of case reports or some case studies that showed some correlation between this. But, you know, case reports, they're useful for flagging, like, potential associations, but they themselves don't establish the causation or even give you a real estimation of what the risk is to regular people. So it's kind of like when we're developing, when we're searching for treatments for whatever, and we notice a correlation between this and that. That gives you an area of study and science, and you go look and you try to say, oh, is that really a thing? Or was this just a random association? So these case studies, they can be something or they can just be random associations. So if you look across the literature trying to link topical tretinoin to intracranial hypertension, you find some typical things about it. So there are just a very small number of cases. So we're talking single digits here. So there are not a lot of cases. There are some cases where there is, but, you know, you're talking less than a dozen people. Also, the patients that had that frequently, they had other risk factors, like having prior intracranial hypertension, obesity, hormonal factors or other things, and the symptoms usually resolved right after discontinuation, which suggests it's like a temporary association, but not really. It doesn't really prove the mechanism here. Right. But I think the most important thing is that there are no large epidemiological studies that show an increased incident of intracranial hypertension in people who use topical tretinoin compared to the general population. So that right there suggests that if it's really a problem, we would have seen it, right?

A (34:20)

Well, yeah, if people are reporting it. Right. If people have issues, if people get a really good, you know, patient intake, what are all the things that you're taking? Maybe, you know, I'm not going to disclose. I'm taking this acne cream. The information occurred to you.

B (34:37)

Yeah, yeah.

A (34:38)

Is as only good as it is. And I would love to see this as like a very specific question. Like, if you go into the hospital and you have entercranial hypertension, it's like a checklist, like, do you take tretinoin or other retinoids? And then it's like, boom. Then you could start to gather the large amounts of information that would be recorded, required to make an assumption. Because as you've, you know, said, people have been taking Tretinoin for decades. Right. So.

B (35:08)

Right.

A (35:09)

Presumably, yeah, millions of people. Yeah, millions and millions and millions. So presumably we might know. But again, if people aren't getting the data or they're not thinking to ask, like, you might not know. Sometimes when I was taking migraine medicine, for example, I would ask my doctor, hey, I'm starting to like, feel this thing, is that a side effect? And she's like, well, you know, it could be, I don't know. Right. But you would think with millions of people taking that, they would have like all the side effects and smoking guns. But they only have what's been reported in like the clinical trials or if you report it to the FDA yourself.

B (35:48)

So I will say it is always amazing to me how little we really know when it comes to medicine and treatments in general.

A (35:56)

It's pretty scary, right? Right.

B (35:58)

Well, you know, every person is like an individual. So, you know, we're, we try to work on a general level. So it's really hard. But I will also say one of the main reasons that to be skeptical that this topical tretinoin is really causing this is because there's a really low level of systemic absorption. So when you put tretinoin on your skin, generally blood levels are really undetectably changed with the amount of retinoids in your bloodstream. So basically it doesn't get all the way into your body. And so from a pharmacokinetic standpoint, it just simply doesn't build up in your bloodstream the same way that a supplement would or an oral version of it would.

A (36:45)

And retinoids and tretinoin and isotretinoin and all these other variables are regulated for use in cosmetics. So it's unlikely that they would be at some dose to cause that bloodstream trigger.

B (37:01)

Yeah. So in general, topical tretinoin, it's not meaningfully associated with intracranial hypertension for the general population at the moment.

A (37:11)

Yeah. Wow. What a really great question. Thanks so much, Ryan. Our last question comes to us from Theresa.

B (37:18)

Teresa says, I know they make aerosol and non aerosol hairsprays. I have never seen a salon or professional use a non aerosol though. So what is the difference and when would a non aerosol be beneficial? You know, I've seen professionals use non aerosol before, but mostly they do use aerosol, right?

A (37:39)

Yeah, no, they don't like it. So I came from a brand that had a aerosol line and a non aerosol hairspray line and the aerosol always way outsold the non aerosol. And this Is because when you have a aerosol, you have very little water or watery things in the can. It's primarily propellant which expels all of the hairspray ingredients. They hit the hair and then the propellant goes away into the atmosphere. When you have a non aerosol version, you don't have propellant as the basis. You have water. And that means water hits the hair and the water doesn't go away from the hair like a aerosol propellant does. So the hair stays wet for a little bit longer, which is not as desirable. Especially. Especially because a hairspray is supposed to be a finishing product. That's how it's regulated in California and many other states follow that regulation. And so you can't finish the hair when you make it wet again. So it's just not a desirable thing. Right. So that is why, in my opinion, most salon professionals use aerosol based products, because they can finish the hair and it keeps the look as they did instead of renting, wetting it. Like the non aerosol hairsprays are just not, they're just not as desirable. And especially now that regulations are getting more restricted, California is saying lower, lower, lower on these volatile components. It's really hard to make good non aerosol hairsprays.

B (39:14)

Yeah, well, it's. It makes it harder to make good aerosol hairsprays too. When you have 55% water in there.

A (39:23)

Well, now it's going to be 50. Wow. Well, it used to be 80. Remember those days?

B (39:30)

Well, we are going backwards. It used to not have a limit. Right. Because I think 80 was.

A (39:35)

I wasn't around then. Yeah, well, some states in the US still accept 80% and so we still had some 80 sprays. And in Europe, surprisingly at the time, they didn't really care about VOC content. So they also get a lot of 80%.

B (39:51)

A VOC, for the uninitiated, is volatile organic compounds. Now, California has always led our country in regulation of VOCs. And I think it's primarily because of all the cars in California and all the smog. Right?

A (40:07)

Yeah. Now they regulate every industry, everything that could put anything into the air. They're probing.

B (40:14)

Yeah, yeah. It's just a lot harder to regulate the cars than it is to regulate beauty products. Even though if you're looking at the amount of impact, it's. They're just, you know, beauty products are negligible compared to what a car puts in the air.

A (40:30)

Yeah. Don't even get me started. So the agency that regulates this is the California Air Resources Board. And Now, Perry, they're looking at fragrance. Fragrance used to be excluded. Now they're saying, well, if we actually looked at fragrance because it is volatile, it goes into the air and hits your nose, could we get some additional emission savings here? And so they're, they're doing those surveys now. So always squeezing, you know they're being.

B (40:57)

Do gooders and you know their heart's in the right place. They want to be better for the environment. Whether they're actually and better for the environment, that's debatable.

A (41:06)

That is debatable. Well, I hear the music. We have to run and get ready for Christmas. Thanks everyone for listening. If you get a chance, head over to Apple Podcasts or Spotify and leave us a review that's going to help other people find the show and ensure we have a full docket of beauty questions to answer.

B (41:22)

And speaking of questions, if you have one and you want to hear your voice on the show, you can just record it on your smartphone and email it to thebeautybrainsmail.com or you can just use the form in the show notes or even call our phone number and leave a voicemail. That's 872-216-1856. And if you're outside the US you got to put an 01 in front of that. Also, the Beauty Brains are on Patreon. If you like what we do and you want to support the show and you also appreciate that we don't have commercials, that's because we have people who listen who support us on Patreon. So if you want to support the show and get a higher priority of your questions answered, go to patreon.com thebeautybrains and subscribe at any level. We thank all of our patrons and in the coming year, we're gonna do more for our patrons. Right? 2026, we'll do more for patrons.

A (42:15)

Now, these aren't empty promises, guys. We actually have a meeting on the calendar this Saturday to discuss how can we do more for you guys and actually follow through on it. That's, you know, that's not just an idea meeting. It's an execution meeting. So I'm very excited. Also, don't forget to follow us on our various social media accounts. On Instagram, we're at The Beauty Brains 2018 on X, we're at the Beauty Brains. On Blue Sky Worth the Beauty Brains, we have a Facebook Facebook page, a TikTok and a YouTube.

B (42:40)

You know, I started a TikTok page for my porch kitties, so look up porch kitty for TikTok, if you're interested in that.

A (42:50)

Well, thanks again for listening, everyone. And remember, be brainy about your beauty.

B (42:55)

Thanks, everyone. Kittens.