Tuesday, February 28, 2012

Question: Does glycerin draw water from your skin when the humidity is low?

I'm still on a quest to figure out the answer to this question...so let's review information I've found so far.

What is a humectant? "Humectancy or hygroscopy is the tendency of a substance to attract water from the surroundings by absorption and adsorption at defined conditions (temperature, humidity)." (page 26, this review).

Is glycerin a humectant? Yes. "Pure glycerol absorbs its own weight in water over 3 days." (page 23, this review)

Does glycerin remove water from your skin in low humidity environments? Let's review what I've found so far...

From SW Gloves News: "Glycerin is also a humectant, which means it attracts moisture to your skin. However, if the air is less than 65% humidity, glycerin will instead draw moisture out of the lower layers of your skin. The moisture is held on the surface of your skin, effectively drying it from the inside out. This results in the upper layers of skin feeling soft and conditioned, while in reality the newly formed inner layers are drying out." (They are referencing this site Natural Health Information Centre, which adds, "It doesn't take a rocket scientist to work out that if you keep drying out the skin from the inside out, it will get progressively worse!") There is no citation from the Natural Health Information Centre about where they found this information.

From Dermatology Times, we get this quote,"While glycerin is a highly effective moisturizing ingredient in low-humidity climates (such as those found in Arizona, Nevada and New Mexico), it can leave skin with a sticky feel in humid environments (such as those found in Florida, Louisiana and Mississippi.) This is because glycerin can also attract water from the air." I'm inclined to go with the words of Zoe Diana Draelos, M.D., over SW Gloves News and Natural Health Information Centre, but let's not stop here!

From The Biology of Women, from a chapter entitled, Cosmetics: The Multibillion Dollar Put-On, we see this quote, "Advertisements imply that such agents have the ability to draw water out out of the air and bring it to the skin surface. It is very unlikely that humectants actually transfer water out of the atmosphere to the skin. They are, in fact, nondirectional. If humectants were used alone or in high enough proportions they would be just as likely to pull water out of the skin. The only way that a high concentration of glycerine (or glycerol, which is the same substance) can be useful for dry skin is under conditions of very high atmospheric humidity of 90% or more. Of course, if the humidity is very high, dry skin would not be a problem."

I had wanted to present these quotes without comment, but I don't think I can in this case as most of the preceding paragraph is simply inaccurate. I want to highlight the sentence "If humectants were used alone...they would be just as likely to pull water out of the skin" because this is the crux of the entire argument about glycerin drawing water out of your skin when it isn't humid. Remember that part - if humectants were used alone - and ignore most of the rest of the paragraph. I just think things need to be put into context, and to take that one phrase out of this wildly inaccurate paragraph would be cherry picking information to make my case, and I hate that! 

"They [humectants] are able to attract water from the atmosphere (if the atmospheric humidity is greater than 80%) and from the underlying dermis. Although humectants may draw water from the environment to help hydrate the skin, in low humidity conditions, they may take water from the deeper epidermis and dermis, resulting in increased skin dryness. For this reason, they work better with occlusives." (Cosmetic Dermatology: Principles and Practice by Leslie Baumann, page 94.)

"Creating an occlusive barrier is more effective in combination with a humectant to draw water to the stratum corneum. Using a humectant alone will draw water to the outer surface of the skin, which will be lost to the environment with an impaired [skin] barrier. However, moisturizers without humectants may also make the skin more susceptible to irritation." (Lippincott's Primary Care Dermatology, page 31).

From this study, "In every experiment, the temperature was held constant at 25˚C, and the starting relative humidity (RH) was set to 0% RH. The RH was programmed to step in 10% increments ending at 90% RH. The RH was incremented to the next level only when the mass change was less than 0.005%/min. NaPCA [sodium PCA] was a more effective humectant at high relative humidities (above 60% RH); while glycerin performed better at humidities below 40% RH. Washing the skin with sodium lauryl sulfate (SLS) reduced the skin’s ability to absorb water more so than washing with Tween 80, a milder surfactant. Vaseline petroleum jelly enhanced the water-retention properties of untreated skin." From page 39, "Glycerin outperforms NaPCA at humidities below 40%." Page 40, "Clearly, Table 3 shows that the skin samples treated with Vaseline experienced a lower rate of water loss." Page 40, "Of the moisturizers that were examined in this study, glycerin was one of the most efficient at absorbing water at low relative humidities." Page 41, "Because occlusion prevents water evaporation, occluded skin has a higher water content compared with unoccluded skin. Occlusion can be achieved mechanically or chemically, by applying a hydrophobic material or film."

"...glycerol does not act as humectant at such a low humidity..." (This review, page 27, near the bottom)

In this study, the abstract notes that "In vitro studies have shown glycerin to prevent crystallization of stratum corneum model lipid mixture at low room humidity."

What can we conclude from these studies and writings? Humectants draw water out of the atmosphere to skin, but when it is less humid, humectants may draw water from under the skin to outside the skin (remember the idea of osmosis!). Not just glycerin, but any humectant, including honeyquat, sodium lactate, sodium PCA, tamarind seed extract, and so on: Any humectant has this potential. If we include an occlusive ingredient with the humectant, this should stop the water from evaporating and will help moisturize our skin.

A couple of questions...

  • Why is the idea of drawing water out of your skin only about glycerin and never about the other humectants? 
  • How much glycerin do I need to use for this effect to make my skin really dry?
  • Why do the authors of scientific studies of glycerin - and other humectants - never mention the humidity in their part of the world? Wouldn't this have a huge impact on the results of the study? 
  • At what humidity level does it draw water from your skin? If it is a well known fact that glycerin draws water from your skin, wouldn't the humidity level at which this starts to happen also be a well known fact? There should be some kind of chart or information showing that at this humidity and below, glycerin is a dessicant and above this humidity and higher, glycerin is a humectant. I can't find anything like that! 

There is evidence demonstrating that although glycerin might not be a good humectant at low humidity levels, it offers other benefits - for instance, helping to keep our stratum corneum lipids from crystallizing - more about this in a near future post - which makes it very valuable, indeed! And there's some evidence a'brewing that use of a humectant can increase mildness in our products. (I will be writing about this in the very near future!)

Would I say that glycerin draws water from your skin when the humidity is low based on what I've read? No. I think there is that potential from a chemistry perspective, but I think there's strong evidence that using an occlusive ingredient with glycerin - or any humectant - will prevent this from happening in real life. I think there's way too much evidence showing that glycerin performs amazingly well as a moisturizer that can offer a ton of benefits beyond drawing water to my skin to not use it. I do think that most of the information about glycerin drawing water from our skin comes from popular media or websites, and I don't think this claim is substantiated.

Would I use glycerin in my products at 20% humidity? At 10%? At 5%? Yes, and I have. I would not hesitate to suggest using glycerin in products for low humidity environments. I think there are other humectants that might perform better in those environments, but it sounds like none of the humectants we can access - see list above! - will work well in a really dry environment. You'll have to get your moisturization from somewhere else!

Join me tomorrow for more fun with humectants!

Monday, February 27, 2012

Chemistry Thursday (on a Monday!): Electrolytes

What are electrolytes? (And are they really what plants crave?) "An electrolyte is any substance containing free ions that make the substance electrically conductive. The most typical electrolyte is an ionic solution, but molten electrolytes and solid electrolytes are also possible. Commonly, electrolytes are solutions of acids, bases or salts." (From Wikipedia). In other words, when you take something like sodium chloride - a salt - and mix it into a solvent - like water - you have an electrolyte! (If you add a little sugar and colouring to this mixture, you've got Gatorade!)

You might recall from yesterday that when we have more salt on one side of a barrier than another, osmosis tries to balance the concentration of salt so both sides have the same amount. We can extrapolate this to mean that if we have more electrolytes on one side of a barrier, osmosis will kick in to try make things even. This is one of the reasons we drink things like Gatorade when we're exercising - as we sweat, we lose salt, so we try to replenish it with something containing electrolytes.

If you're making a gel, electrolytes become really important because some gels will not gel if the concentration of electrolytes is really high. Aloe vera is very high in electrolytes, which is why it can be difficult to create your own aloe vera gel!

*If you want to know what plants crave, check out this clip from Idiocracy on Brawndo: The Thirst Mutilator! If you haven't seen this movie, I encourage you to check it out. I don't tend to watch a lot of movies - I think the last one I saw was Up, which was just lovely, or Flight 666 - but Idiocracy was awesome! 

Sunday, February 26, 2012

Chemistry Thursday (on Sunday): Osmosis

What the heck is osmosis? "Osmosis is the movement of solvent molecules through a selectively permeable membrane into a region of higher solute concentration, aiming to equalize the solute concentrations on the two sides. It may also be used to describe a physical process in which any solvent moves, without input of energy, across a semipermeable membrane (permeable to the solvent, but not the solute) separating two solutions of different concentrations." It's a type of passive transport, which means it doesn't require energy to make it happen.

An easier way to look at it is to think of osmosis as a process of balancing out a concentration of something. There's more of something on one side of the barrier and less on the other side, so it's an attempt to balance it out so there's relatively equal amounts of each thing on each side. In the case of the red blood cells, you can see that it's trying to balance out how much water is on each side of its membrane. It takes a little in - oops, too much - then lets some out. It will do this until the water amount is just right!

This is one of the reasons we can't drink sea water! Sea water contains high levels of salt (sodium chloride or NaCl), so much salt that our bodies can't excrete the sodium quick enough to bring our bodies into balance. The concentration of sodium in our blood reaches toxic levels, "removing water from cells and interfering with nerve conduction". (From Wikipedia) We have a seizure, then die.

Water, water, everywhere, and all the boards did shrink.
Water, water, everywhere, nor any drop to drink.
- Rime of the Ancient Mariner.

Check out the song "Rime of the Ancient Mariner" from Iron Maiden's album, Powerslave. Awesome! Completely and utterly awesome! I couldn't resist an Iron Maiden reference in a chemistry post!

This is one of the arguments for why glycerin allegedly removes water from your skin when it's not so humid outside, which is why it's Chemistry Sunday - I'm researching this claim, and realized that osmosis is an important part of understanding how our skin works!

Here's a little video on the process of osmosis!

Join me tomorrow for more fun with chemistry as we take a look at electrolytes!

Saturday, February 25, 2012

Humectants: A lotion maker's best friend or moisture thief?

I've always thought of February 27, 2009, as the official birthday of the blog as this is when I decided to blog every single day about some kind of bath or body thing, be it an ingredient, a recipe, or a fun fact to know and learn. One of the earlier posts was entitled Humecants are a girl's best friend, and I wrote a little bit about each humectant along with my basic recipe. A few weeks later, I wrote up a post about the chemistry of humectants - Better crafting through chemistry: Humectants. Well, it's time to revisit the topic of humectants with a lot more science and study citing (and fewer assumptions about the gender of my readers!).

The first question I want to pose to you is this...where did you get the idea that adding glycerin to lotion or hair care product could result in glycerin sucking the moisture from your skin or hair? Please provide me with information like "this forum", "this web page", "this book", and so on. If you can't remember, then saying "I can't remember..." isn't a bad thing!

Join me tomorrow as we review some skin biology so we can understand how moisturization actually works! (If you're a keener, click here as this is where we'll be starting!) Then we'll take a look at our hair and moisturization!

I realize this might not look like I'm listening to you with the whole what do you want to know post, but I thought we could use a little review about humectants, how they work, how moisturizing works, how our skin works, how our hair works, and a few other things, while taking a deeper look at humectants, which are huge in the cosmeceutical and hair care products right now! The more you know about these issues, the more power you have to analyze whether an ingredient brings what you want to your facial, body care, or hair care product! 

Related posts:
Chemistry of our skin: An overview
Chemistry of our skin: Natural moisturizing factor
Chemistry of our skin: Transepidermal water loss
Skin chemistry & types section of the blog

Chemistry of our hair: An overview
Chemistry of our hair: What does "good condition" mean?
Chemistry of our hair: What does damaged mean?
Hair care section of the blog

Friday, February 24, 2012

Some questions I've been asked this week about xanthan gum

In this post on xanthan gum, Anonymous writes: Hi Susan! Just wanted to make sure I understood right, is it ok to use xanthan gum up to 2%, even for mild facial cleansers? Some say xanthan gum lowers the shelf life of products. Is that true? Lastly, I really like using polyquat 7 because it makes using the soap a lot more pleasurable, what would be a good substitute for this if I cannot use pq7? Thanks!

It's okay to use xanthan gum at up to 2%, but 0.1% to 0.3% is the suggested usage rate. As you saw in the post on xanthan gum, I used it at much higher levels and things were just fine, but it's not something I suggest. (The reason: Because it can feel gummy and sticky and slough off in little balls when you rub the product into your skin!)

It depends on what you mean by lowering the shelf life. If you use an ingredient with a shorter shelf life than something else - for instance, adding hempseed oil to shea butter - your expiry date becomes that of the shorter shelf life ingredient. Shea butter has a shelf life of about two years. Hempseed oil can be as short as three months. Therefore, the product should expire in three months. So the only way that xanthan gum will reduce the shelf life of the product is if its shelf life is lower than the rest of the product.

What is the shelf life of xanthan gum? According to Answers.com - 1 year. This is the best reference I could find! 

You're asking about the polyquat 7 in your product because we know xanthan gum doesn't play well with cationic ingredients like polyquat 7, polyquat 10, polyquat 44, honeyquat, cationic guar gum, BTMS-50, BTMS-25, Incroquat CR, cetrimonium bromide, cetrimonium chloride, and so on. I suggest using something to increase the slip and glide of your product, like a water soluble ester - I like water soluble shea butter in a body wash and water soluble olive oil in a facial cleanser - or add some Crothix to the mix. (I know Crothix thickens and your point is to thicken your product, but it is a great emollient, too!) You can add some oils to the product by solublizing them in some polysorbate 80 or something like Cromollient SCE to give it more slip and glide, but if you have really oily skin, this isn't a good option. There really isn't a great alternative for the polyquat 7 that isn't a cationic polymer, but I hope I've offered a few options.

Personally, if I had to choose between my cationic polymer and xanthan gum, I'd choose the cationic polymer any day. Besides, Crothix is great for increasing mildness and emolliency of a facial cleanser. Or put it in a foamer bottle and don't worry about thickening at all! 

In the same post, another Anonymous writes: I have a lotion recipe that I made but the lotion is a little thin. Is there a way I can thicken the already-made lotion using xanthan gum?

No. Once you've made a lotion, you can't add anything to it. You could compromise the preservative system or you could mess up with the chemistry - for instance, if you have a cationic ingredient in there that could mess with the xanthan gum. Sorry to be the bearer of bad news, but you really do want to add the xanthan gum in the heated phase. (I have used it in the cool down phase, and it didn't go really well...it was okay, but not the superior product I expect my lotions to be!)

Related post:
How do anti-oxidants affect the shelf life of our products?
Determining the shelf life of your products.
Can you re-heat a finished lotion?

Thursday, February 23, 2012

Chemistry Thursday: What is a molecule?

What does it mean if something is a molecule? "A molecule is an electrically neutral group of two or more atoms held together by covalent chemical bonds." (Wikipedia). In other words, a molecule is when you have two or more atoms bound together in some way. One atom does not make a molecule - hydrogen on its own is just an atom, but combine it with another hydrogen and an oxygen atom and you've got at water molecule!

A molecule may consist of atoms of the same element. Take a look at ozone - it consists of three oxygen atoms bonded together. It's O3 - an ozone molecule. So a molecule can contain two or more of the same element.

We can have small molecules - take something like sodium chloride - or large molecules - like DNA.

A quick aside...I've heard a lot of talk lately about how our skin absorbs oils or how oils penetrate our skin - this isn't really an issue. (Click here for a post on our skin!) Fatty acids are considered fairly decent sized molecules - as you can see from this oleic acid molecule - and they don't tend to penetrate our skin. (That's why jojoba oil is considered unique in that it likes to penetrate our skin through the hair follicles!)

I say "they don't tend..." because there could be some current research I haven't seen that shows that some of the smaller fatty acids can penetrate our skin or there could be some information on penetration enhancers that I haven't read. I can't be completely certain and completely up to the minute on my science here! 

Wednesday, February 22, 2012

Substitutions: Playing around with a basic recipe

As I mentioned in yesterday's post on substitutions, I simply can't make a substitutions list because substituting one ingredient for another is a matter of personal preference and context. There are some ingredients you can't leave out - for instance, you must have an emulsifier in a lotion and no water containing product should ever not have a preservative - and there are some that are optional - we don't have to have cetyl alcohol or stearic acid in every single lotion!

Learning what each ingredient brings to the recipe means you can have a field day substituting things all over the place! You've probably noticed that my basic lotion recipes contain generic terms like oils, butters, emulsifiers, and preservatives. This is because the basic chemistry of a lotion requires you to have certain ingredients, like water and emulsifiers, but you can mix and match what you want in the product. If you like a drier feeling lotion, then use BTMS-50 as your emulsifier, and mango butter and hazelnut oil as your emollients. If you like a greasier feeling lotion, then use Polawax as the emulsifier, and cocoa butter and soy bean oil as your emollients. If you have BTMS-50 but don't like a dry feeling lotion, choose babassu oil and soy bean oil or cocoa butter and sunflower or another greasier feeling butter and greasier feeling oil to compensate for the powderiness of BTMS-50. And so on.

But how do you know what kind of lotion you like? Know your ingredients, and spend lots of time in your workshop! (Look to your right - there's a whole bunch of information on ingredients there!) Everyone thinks they want a drier feeling lotion, but you're probably comparing the idea of greasy vs. non-greasy with lotions you've purchased in shops. Homemade lotions are almost always less greasy than store bought products! (Click here for my post on greasiness in lotions!)

I really recommend reading the modifying lotions with ingredients you have - part 1 and part 2 - and how to tweak that amazing recipe before continuing on with this post if you aren't that familiar with the idea of substituting ingredients. I can wait. I need another cup of tea, anyway. Welcome back! Okay, so now that you get an idea of how to substitute, let's have some fun with a recipe.

BASIC, SLIGHTLY MODIFIED LOTION RECIPE (from this post)

HEATED WATER PHASE
67% water
2% humectant

HEATED OIL PHASE
15% oil
5% butter
3% fatty alcohol or fatty acid
6% emulsifier (BTMS or Polawax)

COOL DOWN PHASE
1% fragrance or essential oil
0.5% to 1% preservative

What can you do with this recipe? Well, just about anything as it's a generic recipe and you can fill in the blanks! What oil you like? Which butter do you prefer? Do you want to use stearic acid, cetyl alcohol, cetearyl alcohol, behenyl alcohol, or cetyl esters? Do you want a powdery skin feel or a greasy skin feel?

BASIC, SLIGHTLY MODIFIED LOTION RECIPE WITH MINIMALLY PROCESSED INGREDIENTS
HEATED WATER PHASE
67% water
2% honey

HEATED OIL PHASE
15% oils - 7.5% avocado oil, 7.5% hemp seed oil
5% butters - cocoa butter
3% stearic acid
6% emulsifier - Polawax

COOL DOWN PHASE
0.5% preservative
1% essential oil - lavender

How do you think this lotion might feel as you rub it on your skin? How will it feel after a few minutes? Do you think it has some kind of staying power or will it feel like it's been absorbed quickly? What kind of thickness can you expect?

As a note, our skin doesn't really absorb the oils - the fatty acid molecules are far too large to pass through our skin's barrier - but it might feel like it's all disappeared. It's a figure of speech, not a biological process.

Let's try another one.

BASIC, SLIGHTLY MODIFIED LOTION RECIPE WITH SILICONES & ESTERS
HEATED WATER PHASE
67% water
2% sodium lactate

HEATED OIL PHASE
5% fractionated coconut oil
6% cetearyl ethylhexanoate
5% babassu oil
3% cetyl alcohol
6% Incroquat BTMS-50

COOL DOWN PHASE
2% dimethicone
2% cyclomethicone
1% fragrance oil
0.5% preservative

How do you think this lotion might feel as you rub it on your skin? How will it feel after a few minutes? Do you think it has some kind of staying power or will it feel like it's been absorbed quickly? What kind of thickness can you expect?

Take this basic recipe and play around with it a bit to find some combinations you like, then go make it! See how you like it, and whether or not you'd do it again!

Related posts:
Can we substitute one oil for another?
Any and all the ingredients posts (look to the right for the list!)

Tuesday, February 21, 2012

Substituting one ingredient for another

One of the things I'm regularly asked for is a list of things you can substitute with other things. (Recently from the post what do you want to know?) I'm happy to write something like that up...but every time I try, I'm bogged down by the idea that you can substitute so many things for other things that I don't get past the fourth item!

The easiest way to know how to substitute one ingredient for another is to know your ingredients. 

Picture this as my substitution suggestion: If you don't have cetyl alcohol, then use stearic acid. It's a good suggestion, but I could also suggest behenyl alcohol, cetearyl alcohol, or cetyl esters. I could just as easily suggest that you add some mango, cocoa, kokum, sal, or shea butter if your goal is to thicken the product. Each suggestion is dependent upon the type of product you're making.

Let's say I make a blanket suggestion to use mango butter in place of cetyl alcohol for thickening power...if I were to make some hair conditioner, I've just reduced the conditioning power and increased the greasiness. If we were making a body butter, I've just reduced the feeling of greasiness, but I've also reduced the thickness. If we were making a whipped shea butter, I've just removed something that will stiffen the product pretty dramatically and added another butter that will do nothing for the melting point. If we were making...well, you get the idea.

If you've ever substituted stearic acid for cetyl alcohol in a body lotion recipe, you'll know that it affects the skin feel of your product. Cetyl alcohol makes my body butter feel and look like Cool Whip, all shiny and soft, easy to spread on my skin. Stearic acid makes it look and feel like whipped butter, harder to get out of the container, harder to spread, but longer lasting on my skin. It's amazing how just a 3% switch can radically change a product.

If you want to know about a substitution for cetrimonium chloride, for example, learn what cetrimonium chloride brings to the party. From the post on this ingredient, "it isn't as lubricating as BTMS or cetab (cetrimonium bromide), but it does have a unique ability to detangle, which means it reduces the combing forces and friction in your hair, which is a very very good thing." If we wanted to find something else that might work in place of cetac, we know that it isn't as lubricating as BTMS or cetrimonium bromide, so those won't be substitutions, and we know that it detangles and reduces combing forces and friction on our hair, so that's the quality we want to find in another ingredient.

What else can act as a detangler? We know BTMS and cetrimonium bromide detangle, but not as well as cetac. What about Incroquat CR? It's "a good detangler and a good anti-static product." This might work! Or we could just leave out the cetrimonium chloride and see what happens.

Incroquat CR would be my official substitution suggestion for cetrimonium chloride, but there really is no substitution for its detangling awesomeness. I've tried every variation I can think of to get more detangling without cetrimonium chloride, and it really is a unique ingredient that does what it says very well at up to 2% in your conditioner!

The only way to really know what you can substitute and what will feel good to your skin is to learn your ingredients and what each brings to your products. You know if you like a greasy or dry feeling lotion, so only you can decide if you want to switch the butter for cocoa or mango. They offer the same function in a body butter - they thicken and offer serious emollience - but they will feel very different.

Substitutions are dependent upon the function of the ingredient in the product and the function of the product, and it's hard to separate one from the other. The information on this blog is also dependent upon my personal preferences - for thickeners, I could suggest using something like xanthan gum or a polymer, but I generally don't - and what I have available to me at my local retailers. I can make suggestions like this one - stearic acid and cetyl alcohol can be interchanged when they behave as thickeners in a recipe - but it really is up to you to know your ingredients, your personal preferences, and your product.

I know this isn't an easy suggestion. It takes time to learn your ingredients, then learn how to use them, and time isn't something we all have a lot of these days. But if you want to make substitutions or be able to make your own recipes, you have to learn what each ingredient brings to the product and know what they feel like on your skin.

Let's take a few days to look at a few substitutions and how they might affect our products!

Related posts: All the posts with substitutions in the label!
Figuring out what's important in a conditioner

Monday, February 20, 2012

Question: What oils are good for your hair?

Sarah wrote in this postI have a question... which oils would you please suggest for hair leave-in conditioners? I see you've mentioned coconut, camellia, sea buckthorn, jojoba, avocado in some posts, but is there a post that discusses recommended oils for different hair types (with reference to their properties)? 

There doesn't tend to be a huge difference in using oils on our hair the way there is for oils on our skin. You'll see me write about something like sunflower oil as containing a lot of linoleic acid, so it's good for skin that needs some repair or something like olive oil containing a lot of oleic acid, so it's good for skin that needs moisturizing and softening, and we can extrapolate from that information that someone with wind chapped skin, for instance, could probably benefit from something like sunflower oil because there's been some damage to the skin's barrier or that someone who has callouses could benefit from olive oil for the softening. But there isn't that kind of information about hair.

When it comes to oils and butters in hair care products, for the most part you're really choosing them for their ability to moisturize your scalp and coat the hair strand. Which means you can choose the butter or oil you like - cocoa butter, shea butter, sunflower oil, and so on - and it really won't make a massive difference to the actual hair strand. Most fatty acid molecules are simply too big to penetrate into the hair shaft, so most of it will rinse out when you rinse the conditioner out of your hair. If you're using them in a leave in conditioner, you can choose pretty much anything you want if you're looking to coat the hair strand.

If you're looking for an oil to include in your hair care product, the first one I'd use would be coconut oil. Coconut oil has had a lot of studies done about it, and they've shown that lauric acid has an affinity for hair proteins and the molecules are small enough to penetrate the hair strand. (Click here for a recipe...) Virgin coconut oil offers the same features, and it smells wonderfully of coconuts! Jojoba oil is interesting in that it penetrates your hair follicle, so it will offer some cleansing and moisturizing of your scalp. Olive oil will help your scalp, but it's not going to penetrate your hair strand. Sea buckthorn oil might be good for your scalp, but I haven't found evidence it works well for your hair, and avocado oil is supposed to be great for itchy scalps - no doubt thanks to the oleic acid - but there's nothing saying it does more for your hair than other oils. (I know there's talk about argan oil being good for our hair, but I can't find anything to back up that claim.)

Lauric acid is a smaller molecule than something like stearic acid, oleic acid, linoleic acid, and so on, which is part of the reason it can penetrate the hair shaft. If you use another oil that contains lauric acid - like babassu oil or murumuru butter - you might get some of the same benefits as using coconut oil. 

It seems that when people are looking to use oils to moisturize their hair, they're really looking for more conditioning or more water retention, and neither of these goals is accomplished well by including more oils in hair care products. If you have really dry hair, you're better off incorporating more humectants into your products to draw water from the atmosphere to your hair. Adding some glycerin, honeyquat (which conditions as well), sorbitol, or another humectant to your product will increase the moisturization level of the product better than adding an oil.

If you are looking for more conditioning, adding more cationic quaternary compound - like Incroquat BTMS-50, Incroquat BTMS-25, Incroquat CR, cetrimonium bromide, behentrimonium methosulfate, and so on - will increase the conditioning of the product. Adding a fatty alcohol at up to 50% of the conditioning agent - something like cetyl alcohol, cetearyl alcohol, behenyl alcohol - will boost the substantivity of the product.

If you really are looking to include a ton of oils in your products, then I've included some links below that might help!

So the short answer for Sarah's question is that if you want to add an oil to a leave in conditioner to benefit your hair strand, I'd go for coconut oil or another oil with lauric acid. If you want to add an oil to a leave in conditioner to help your scalp, then you have quite a few to choose from. Go for something that you like and have around the house because there isn't a big difference in carrier and exotic oils when it comes to moisturizing your scalp or coating your hair strand.

I know there will be people who disagree with me, and that's great. Send me along the links for the information you provide and I'll read them! 

Related posts:
Adding slip to hair care products with fatty alcohols
Conditioners: Humectants and frizz
Adding slip to conditioners with oils and butters
Hair care section of the blog
Emollients - oils, butters & esters - section of the blog
E-mail question: Using oils in our hair care products

Sunday, February 19, 2012

Question: How many oils is too many oils?

Darina e-mailed me to ask: My question is how many oils is too many?  What I mean is you are creating a formulation perhaps a lotion or a cream does there come a point where adding another base oil is just over the top and not beneficial. I'm experimenting with a cleanser at the moment. The main ingredient will be olive oil, but I'll have castor for its cleansing properties, I also want rosehip for its benefits, I'd love some Jojoba and I'd love some wheatgerm in there too but now I'm thinking is that just too many! They all have their own little uses and benefits and I want them in there for those reasons but maybe it's just counter productive?

Great question! I always ask myself this - what is my end goal? What product am I making? What properties or features do I want in this product? What properties do you want in your oils or emollients? Let's take a look at the oils you mention...

Olive oil: Lots of oleic acid, which can mimic human sebum, but it can make P. acnes bacterium worse. Moisturizing, anti-inflammatory, regenerating, and softening. Should be well absorbed by our skin. Tons of tocopherols and squalane. Shelf life of about a year. A greasy feeling oil. 

Castor oil: Good for cleansing, but doesn't really bring much to the mix by way of tocopherols, phytosterols, polyphenols, or beneficial fatty acids. Shelf life of at least a year. A dryish feeling, thick oil. 

Rosehip oil: Contains great anti-oxidants and free radical scavengers, oleic acid for great moisturizing and softening, linoleic and linolenic acids to help with skin barrier repair and anti-inflammatory properties, something that offers the possibility of some reduction of fine lines and signs of photo-aging, and scar reduction, and Vitamin C. It's been known to make acne worse. Shelf life of six months or so. A dry feeling oil. You want to use this at 6% or more to get the possible reduction of fine lines property. 

Wheat germ oil: Very high in linoleic acid and Vitamin E. It has tons of phytosterols, which help our skin barrier mechanisms recover by penetrating into skin, reducing transepidermal water loss (TEWL), and they can help with sun damaged or harmed by the elements, as well as reducing inflammation and itching. The polyphenols are amazing - ferulic acid is a very effective anti-oxidant - more powerful than Vitamin E - that can prevent skin aging, reduce age spots, helps repair light and radiation induced damage. It penetrates skin to soften and moisturize, soothes wind chapped and sun burned skin, and reduces itching and inflammation. It's also filled with carotenoids like xanthophyll and beta carotene, both of which are precursors to Vitamin A. And the squalene! Wheat germ contains about 0.1% to 0.7% squalene, which is soaked quickly into our skin to soften and moisturize. It has a shelf life of about 6 months. It feels light but greasy. 

Jojoba oil: Contains linoleic acid. It sinks into our skin through the hair follicles - not blocking the follicles, though! - and it mixes with our sebum to create a thin, non-occlusive layer of jojoba oil and sebum. It can help loosen oils, which can be washed away. It doesn't have a ton of Vitamin E, but it has some good phytosterols and polyphenols. It is considered a liquid wax, and has a shelf life of at least 2 years! 

Check the properties of each oil. Then check how much you have to use of each oil. And check the shelf life. Do any of the oils overlap? For instance, if you want the oleic acid of olive oil, could you leave it out in place of more rosehip oil? If you want the Vitamin E of wheat germ oil, but nothing else, could you just add something like a Vitamin E capsule to the mix? Do you really want the slightly occlusive nature of the jojoba oil? Do any of these oils have suggested usages rates - don't go over, don't go under, that kind of thing - that you need to consider? 

Let's say we can only use three oils, what could we choose? Again, what's your end goal?

If I were making a cleaning product for my skin - oily, acne prone, rosacea prone - I would leave out the rosehip and olive oil because I don't want my break outs to get worse. So I'd be using jojoba, castor, and wheat germ oil for my skin. If you were to make something for someone with really dry skin, you might want to choose those oils with higher levels of linoleic acid (to help with barrier damage repair), oleic acid (to help with softening and moisturizing), and high levels of Vitamin E, so you might choose olive oil, wheat germ oil, and castor oil (if you want the cleansing properties).

If I were to make a facial moisturizer, I'd want to leave out the heavier ingredients, so I'd go with the rosehip, olive oil, and wheat germ oils for a dry skin moisturizer. If you like heavier ingredients and you want more occlusion, you might want the jojoba oil along with the rosehip and olive oil.

If I want something with really great label appeal, I'd definitely go for jojoba, wheat germ, and rosehip.

If you were making a body lotion, I'd go for jojoba, olive, and wheat germ because I want the slightly occlusive nature of jojoba with the skin repairing qualities of wheat germ.

And if you were worried about how much something like this might cost, you'd want to go with olive and castor oil. 

Yeah, I know, I haven't made this easier...but it does go to the point that knowing your ingredients and having a clear end goal makes it easier to make these decisions!

So how many oils is too many oils? I really can't answer that question because it's about what you want in a product. I tend to choose two or three oils per product and use them at 10% or more because that seems to be the level that works well for me.

You can use 2% of this, and 3% of that, until you get 8 different oils in your product, but something feels really pointless about that. I feel it's better to choose two or three oils that do what you want and use those - or choose one or two oils that do what we want. You can do the titch of this and titch of that thing, but I don't think you're getting much out of an exotic oil like evening primrose or rose hip or sea buckthorn oil by using it at 2% - better to go with 5% or 10% to really get some value out of it! (This is my opinion. Your opinion may differ. Neither of us are right or wrong - we're just disagreeing!)

To summarize: I think you can have too many oils in a product. (Wow, that took a while to answer, eh?)

Related posts:
Oils & emollients section
Can you substitute one oil for another in a recipe?

Friday, February 17, 2012

What do you know...some answers!

Thanks so much for offering your suggestions for future posts for this blog (click here to see a list and offer up your own!) A few of your suggestions have been written about in the past, and a few might have been written about before! Here are a few for now...

A few of you have asked for information on cosmeceuticals. I did write a series on this topic last year - click here for all the posts under the label "cosmeceutical" - so can you be more specific about what you want to see? Do you want more formulations? More ideas on how to use the ingredients? (I'm going to turn this section into a list with information on things like niacinamide and ferulic acid, as well as vitamins!)

Click here for the new cosmeceuticals section of the blog! 

Quite a few of you have asked for anti-aging products. You know we can't make claims that anything we make will "will prevent wrinkles" or "make you look so young, your wife will have defend herself against accusations of being a cougar", but we could make some base products into which you could add various alleged anti-aging ingredients! I have a few (click on the cosmeceuticals section above). As well, if you're interested in learning more about specific skin types and a few suggestions for them, take a look at this section on skin chemistry to get a few ideas on what kinds of ingredients your aging, rosacea or acne prone skin might like! (And yes, these products will be suitable for men and women!)

There were a few questions about making our own emulsifiers. I'm guessing that you mean the HLB system type emulsifiers? If so, I've written about them extensively on the blog in the past. (Click here for all the HLB posts or click here to start the series (hit "newer post" to see the next one in the series)). After taking a look at those, can you advise what more I can offer in that area?

If you want to know more about mineral make-up, go no further than the section labelled MMU! I have posts on making your own base, turning a blush into a foundation, creating a base from scratch (part 1 and part 2), creating a translucent base, creating an opaque base, and so on. The mineral make-up series starts here - mineral make-up: a primer - and just click "newer post" to see the next entry in the series.

How to know when to add an ingredient to your product? Click here!

Some ideas for substituting when you don't have the ingredient I suggest? Click here for the posts I wrote on substituting! (As for your specific question about what you could substitute for cetrimonium chloride. Nothing. Nothing really replicates what it offers to you hair. You could use Incroquat CR for detangling and softening, but nothing really compares to what cetrimonium chloride brings to your product!) My goal with this entire blog is that my recipes are generic enough to allow you to make loads of changes, and that you can learn enough from the ingredient posts to figure out how to make substitutions.

I really appreciate your help on finding topics for the blog! I'm never sure if I should re-visit a topic or if I should start from scratch, and you've offered some interesting ideas! If you take a look at the links and still don't find the information you want, write to me (comment or email) and let me know!

As for the new ideas, give me a bit and I'll get to making more facial products, like eye creams and sera. Unfortunately, I can't test most of them on me as my skin really doesn't like oils, so I'll have to find some willing guinea pigs in my friends, co-workers, and family! In the meantime, here's the link to 85 facial product recipes and ingredients that might interest you!

And thanks for the idea to do some things on surfactants, Tara! You know that's one of my favourite topics!

As for the picture of the Mario mushroom, it's from a local restaurant - Seven Sushi - and the chef has been having fun with the garnishes! I just thought it was awesome! 

Wednesday, February 15, 2012

What do you want to know?

I'm working on the essential oil series of posts, but I'm thinking about the next series. I'm still working on the facial products e-book - it might be a while, I'm getting rather busy - but I'm wondering what you want to learn? I've been looking at the pages that you like the most and right now the top three pages are chemistry: the atom, biology of the hair strand, and cationic quaternary compounds: cetrimonium chloride, and the hair care section gets at least double the hits of the emollients section. So I'm left to conclude that you want to know more about hair...but what more? (To be honest, I'm not really sure how much more there is to say on hair care - click here for all the posts on that topic - but I'm open to more, if there is more!)

What more do you want to know about any topic (not just hair care)? What is confusing you? Baffling you? Taunting you because you want to know more, but aren't sure what more you want to know? Do you want to know more chemistry? What have you been researching or playing with lately? Do you want to know more about lotions? Skin care? Hair care? Anhydrous products? Was there a post that touched on something but made you want to know more? Be as specific as you can about what you want to know, and I'll do my best to write posts about it. (And feel free to comment on questions posted by other people - this blog is about sharing information, and it doesn't have to be me doing all the sharing!)

As a note, I'm not going to ask you to know every post on the blog - there are 1533 posts and I certainly don't know them all - so let loose on your questions or comments in the comments section of this post! 

Let me know what you want to know and I'll get it on my schedule. (Please note that I still don't want to do any more duplicating, but I'm open to just about everything else!)

Essential oils: Other things about cedarwood

Cedarwood Texas is considered to be an anti-spasmodic, antiseptic, astringent, and expectorant. Cedarwood Virginia is considered to be an abortifacient, antiseborrheic, antiseptic, antispasmodic, astringent, expectorant, fungicidal, and an insecticide. We've already discussed the claims that cedarwood can be an abortifacient (not completely sure, but be careful!), sedative (confirmed), and insecticide (confirmed), but what about the other claims?

ASTRINGENT (Cedarwood Texas and Virginia) and ANTISEBORRHEIC (Cedarwood Virginia)
I've searched and searched and searched, and I can't find anything to confirm that this is an astringent essential oil. I use it as an astringent in my products - generally as part of my oily hair blend of equal parts lemon or lime, rosemary, thyme, and cedarwood - but I can't provide you with any compelling evidence as to why I'm using it in that way.

An aside...What does it mean for something to be astringent? An astringent is actually defined as "chemical that tends to shrink or constrict body tissues, usually locally after topical medicinal application." An ingredient like witch hazel is considered to be astringent thanks to the tannins contained therein. We tend to use astringent ingredients for oily skin or hair to remove sebum so our skin and hair can feel cleaner. 

When I use it, it feels to me like it's astringent and is removing sebum from my hair and skin well, but my anecdotal experience doesn't qualify as science, so I can't call this claim confirmed.

EXPECTORANT: I can't find anything scientific to back up this claim.

ANTISEPTIC: I can't find anything scientific to back up this claim.

FUNGICIDAL: I thought I found something relating to cedarwood Virginia and yeast, but I can't find it again despite a lot of searching.

ANTI-SPASMODIC: Again, I can't find anything.

Although I can provide you with a lot of "it's said that..." and "historically, cedarwood..." statements with lots of links, but it's hard to find good science on this essential oil. I think we've confirmed that it can act as a sedative, that it's wise not to drink it (scroll down to the government report part), that it behaves as a snake annoyer, and it is a possible mollusc killer. But that's about it.

If you have any good studies or reputable scientific sources to help me with these claims, please send them along to me at sjbarclay@telus.net

Join me tomorrow for a few ideas on using cedarwood essential oil.

Tuesday, February 14, 2012

Newbie Tuesday: You made body butter (with a few questions)!

Congratulations! You made a body butter! (Click here for more details about this project on Newbie Tuesday!) If you haven't already done so, pat yourself on the back joyously and moisturize yourself well with the product! (And I still haven't finished the video. I used to be good at this, but I'm having to learn iMovie all over again!)

What did others have to say about this project?

Sciaretta Farms says: I did it! My second ever batch of lotion!

Yay! Great job!

Holly writes: Susan, I jumped the gun! I made the tomorrow's project already. I just used the same technique as for the lotion, and it came out great! I used cocoa butter and peppermint oil and my body butter smells just like a York Peppermint Pattie. (My husband asked if he could eat it.) I think it's time to break out of the box, and I'm ready to do some customizing when I make the cream. I need to explore your blog some more, but I definitely plan on including honey or beeswax.

I don't think I'm the only one envious of your packaging! Lovely! And thank goodness you also have a smart husband who might want to eat it, but knows enough not to eat it (or at least ask - my husband included that bit)! Smart husbands rock! 

And Alex writes: made my body butter and i love it!!to thicken it up would you just increase the amount of butter and decrease the amount of water? or would you be better off using a harder butter? and yes, my first lotion from a couple of weeks ago is all used up!! i've been scouring your facial products posts because i want to make a face moisturizer next!! :-D

And there's the first question...

If you want your body butter to be thicker, what could you do? (There are a few ideas after the recipe, but I'd love to hear your suggestions!) 

BASIC BODY BUTTER RECIPE
HEATED WATER PHASE
59% water
2% sodium lactate or glycerin (optional)

HEATED OIL PHASE
10% oils
15% butter
3% cetyl alcohol
7% Polawax (e-wax)

COOL DOWN PHASE
0.5% to 1% preservative
1% fragrance or essential oil
  • You could reduce your oils by 5% and use 20% butter, 5% oils. 
  • You could reduce your oils completely by 10% and have 25% butter.
  • You could change the type of butter you're using. Mango butter seems to thicken more than shea butter, and cocoa butter thickens more than both of them. 
  • You can use an exotic butter - kokum butter, for instance - that will thicken it even more. 
  • You can switch cetyl alcohol for another thickener - stearic acid, cetearyl alcohol, cetyl esters, and so on (click here for that link).
  • You can add more butters and oils, but this requires a modification of your oil phase - click here for a post on that topic. So increase your butters to make up 30% of the recipe, increase the emulsifier to be 25% of the oil phase (I'll let you do the math), then reduce your water by the increased oil/butter and emulsifier amount. (Definitely read the post on the topic if this is what you want to do!)
And Will asks: How do you make a small amount of cream, such as an "eye cream" that you're going to dump expensive actives into, where your total desired quantity is about an ounce? I'm guessing the answer is to make ten and share, but just in case it's not....

In all honestly, that's what I would do. I'd make my 100 gram batch - about 3.5 ounces - and give the extras to the people whose opinions matter to me. I don't like making things smaller than 100 grams because I could slip my hand just slightly and that 1% becomes 1.9% and that's a big difference in a small amount of product. But you don't want to make a lot, so making a small batch might be a good idea! 

Get yourself an epoxy scale or a scale that measures down to the 0.1 gram, and make yourself a smaller batch. The down side to this is that it doesn't take much to have too much of something. If you scale everything down to make a 30 gram batch - 1 ounce - then you'd be using 0.15 grams of preservative. How do you measure the 0.05 part of this? You could measure 0.1 grams and be happy with it, but there will be a lot of 0.0# grams in the mix. Make sure you are really picky about measuring everything, and make sure you take lots of notes so you can replicate it in a larger size. 

What's next? We're making a cream on February 21st! This means we'll be playing with stearic acid, so if you don't have any yet, you'll want to get some before that date! 

Related posts: 

Essential oils: The science of cedrene and thujopsene

The two other main components of cedarwood Texas and cedarwood Virginia essential oils are cedrene (1.8% in Texas, 27.2% in Virginia) and thujopsene (60% Texas, 27% Virginia). And here's the problem - I've done a ton of searching, and I can't find anything with any great information about what these compounds bring to the science of cedarwood essential oil.

It might be that cedrene offers the same sedative effects as cedrol, although the study was done in 1968, so there might be more information now, (page 15, this report). And "Virginia cedarwood oil (3%), cedrene (2%), and cedrol (2%) were all highly toxic to Peanut Trash Bug colonies..." (page 16, same report).

As for thujopsene, I have nothing on how it might affect us, internally or externally.

So it's hard to say what effects these compounds might have on us in our products when we use cedarwood Virginia or cedarwood Texas essential oils. Let's take a look at some other claims made about cedarwood essential oil (Texas and Virginia) tomorrow.

Essential oils: Cedarwood - the science of cedrol

What exactly is cedrol? It's a sesquiterpenoid alcohol found in cedarwood oil (definition here). It makes up about 19% of cedarwood Texas and 15.8% of cedarwood Virginia. The International Organization for Standardization states cedrol should make up a minimum of 20% in Texas cedarwood and a maximum of 14% in Virginia cedarwood, whereas the Fragrance Manufacturer's Association expects to see 25% to 42% for Texas and 18% to 38% for Virginia. Big difference, eh? (Click here for more information.)

SEDATIVE EFFECTS OF CEDROL
"Previous studies reported that some compounds in cedar wood essence induced behavioral changes including sedative effects. In the present study, we analyzed cardiovascular and respiratory functions while subjects were inhaling fumes of pure compound (Cedrol) which was extracted from cedar wood oil...Statistical analyses indicated that exposure to Cedrol significantly decreased HR (heart rate), SBP (systolic blood pressure), and DBP (diastolic blood pressure) compared to blank air while it increased baroreceptor sensitivity. Furthermore, respiratory rate was reduced during exposure to Cedrol. These results, along with the previous studies reporting close relationship between respiratory and cardiovascular functions, suggest that these changes in respiratory functions were consistent with above cardiovascular alterations...Taken together, these patterns of changes in the autonomic parameters indicated that Cedrol inhalation induced an increase in parasympathetic activity and a reduction in sympathetic activity, consistent with the idea of a relaxant effect of Cedrol." (1)

What's fascinating about the studies on cedrol is that it seems that we don't need to actually be able to smell it to be affected by it! The reaction isn't necessarily about smelling it! This study demonstrated that rats without a sense of smell still responded to cedrol.  "The above findings indicate that cedrol inhalation had marked sedative effects regardless of the animal species or the functional state of the autonomic nerves, suggesting that the mechanism of action is via a pathway other than the olfactory system." And this study notes "The present results provide the first evidence that the lung and lower airway exert an inhibitory influence on the cardiovascular system in response to Cedrol (odorant) in the air under physiological conditions."

So what does this mean? Cedarwood Texas and Virginia might offer some sedative effects via cedrol! Very interesting! (It also means that I really need to reconsider using cedarwood essential oils in my morning shampoo and conditioner if I want to have a hyper day!) I think it's safe to say that we can consider this claim confirmed!

References:
(1) Samantha Dayawansa (a, b., Katsumi Umeno (a, b., Hiromasa Takakura (a, b., Etsuro Hori (a, b., Eiichi Tabuchi (a, b., Yoshinao Nagashima, (., & ... Hisao Nishijo (*, a. (2003). Autonomic responses during inhalation of natural fragrance of “Cedrol” in humans. Autonomic Neuroscience: Basic And Clinical, 10879-86.

Monday, February 13, 2012

XBOX update

I wrote about the "unauthorized access" (aka hacking) of our XBOX account a few weeks ago - here's the update. 

After another phone call to XBOX, I found out that it can take up to FOUR TO SIX MONTHS to restore our account (meaning four to six months to return our points to us, to return our gamer tag to us, and to make sure that everything we've purchased or saved comes back into our name). The reason for this - our account was "migrated" to another region or country. (Apparently our account wanted to create a better life for itself and its children, be near better schools and drinking water, and not be judged for its accent or the colour of its pixels but the contents of its heart.) So they have to restore our account from scratch to be the way it was on December 29th, before the hacking started.

In the meantime, I can't access any saved games, I can't download information, I can't download content or new games, and I can't see leaderboards to know how we've done as players. I can't download stuff for our youth programs, like games for competitions or new content for Rock Band or Guitar Hero. I know this seems like a first world problem - oh no, I can't play video games! - but someone managed to hack into our account, steal our identity and steal the equivalent of money, and to me that is concerning. The fact that it is taking forever to fix the problem without any contact from XBOX - they've admitted they wouldn't have been in contact if I wasn't the one calling - is very concerning. They talk about unauthorized access, instead of using the words "fraud" or "theft"

As an aside...I think that's part of the problem. Using corporate speak sanitizes the matter. It isn't unauthorized access - it's theft, hacking, and fraud. It's illegal activity. Our account didn't migrate - it was forcefully moved to another location. Why make it sound okay?

As an aside, I spoke with Jennifer and Cody today at XBOX and they were very helpful. Patrick on January 27th was great, but last week's conversation with Kyle and Travis didn't go so well. Why today is the first time I'm hearing that it could take four to six months to restore our account I'm not sure. 

How not to be me? DO NOT PUT YOUR CREDIT CARD ON YOUR ACCOUNT. Buy points. And don't buy a lot of them. Buy a Wii. (The Playstation network isn't secure and I think we can extrapolate that XBOX isn't as secure as we'd like, either. I've never heard anything about Wii getting hacked.)

May I suggest a few games for the Wii? If you want a good party game, I'd suggest Super Smash Bros., Mario Party 8 (although 9 is coming out shortly), and Mario Kart. Animal Crossing is a fantastic game and any of the Harvest Moon games. (Yes, a farming simulator. I remember when Raymond brought it home - a farming simulator? And I've played it for years and years and years!) It's a fun system for the whole family!

More updates soon...

Essential oils: Cedarwood Texas and cedarwood Virginia essential oils

The cedarwood essential oils from Texas and Virginia can be very similar, but there are different claims and different processing for each of the oils. 

From Leung's Encyclopedia of Common Natural Ingredients (click here for the excerpt): Cedarwood oil Virginia contains mainly α-and β-cedrene (ca. 80%), cedrol (3–14%), and cedrenol. Other sesquiterpenes present include thujopsene, β-elemene, caryophyllene, cuparene, α-acoradiene ("acorene"), and others. Monoterpenes are also present (mostly sabinene and sabinyl acetate). Cedarwood oil Texas contains similar major constituents as cedarwood oil Virginia. Both types of cedarwood essential oil will annoy snakes. Both are considered phototoxic (although I can't find any references to this except for p. 567 in the Handbook of Essential Oils). 

CEDARWOOD TEXAS (Juniperus ashei)
Texas cedarwood is steam distilled from trees that are felled specifically to create the essential oil (3, p. 76). It is further rectified to remove the orangey-brown colour to make it a nice yellow-y colour and to remove some of the stronger scents. It is considered to be an anti-spasmodic, antiseptic, astringent, and expectorant. 

CEDARWOOD VIRGINIA (Juniperus virginiania)
Virginia cedarwood is steam distilled from branches, stumps, saw dust, and waste wood from trees felled primarily for making furniture. It is reported to be an abortifacient, antiseborrheic, antiseptic, antispasmodic, astringent, expectorant, and an insecticide. It is reported that cedarwood Virginia can cause skin irritation in some sensitive individuals (click here & search for cedarwood) and shouldn't be used by pregnant woman as it has a reputation as an abortifacient. 

Although the government notes in this report that "Historically, nineteenth century medical compendiums contain several reports of abortion and death in humans after oral consumption of relatively large amounts of cedarwood oil..." it goes on to note that that "Although cedarwood oil has been described as a powerful abortifacient, very little data on the toxicity of any of the three cedarwood oils was found in a review of the available literature." I think it wise for pregnant and nursing women to be careful with anything they might use, and I think it wise not to drink a large amount of cedarwood oil as well. 

Cedarwood Virginia is reported to be a good insecticide, and people have traditionally used cedar as a way of repelling moths. It's used in moth proofing and to preserve cloth from moths and beetles (3, p. 885). It is suggested that adding "4–5 drops of cedarwood oil and pine oil is added to a bowl of warm water and a bristle hair brush is soaked with this solution to brush the pet down with it. Eggs and parasites gathered in the brush are rinsed out. This is repeated several times. This solution can be used similarly for livestock after adding citronella and lemon grass oils to this mixture. (3, p. 884). 

Join me tomorrow as we take a look at the science of a few of the compounds we find in cedarwood Texas and Virginia essentials oils! 

References: 
(1) Leung's Encyclopedia of Common Natural Ingredients
(2) The Encyclopedia of Essential Oils (1992) by Julia Lawless
(3) Handbook of Essential Oils: Science, Technology & Applications - Husnu Can Baser & Buchbauer (eds).