# Lavender and Tea Tree - Endocryne Disrupters?



## Saffron (Mar 18, 2018)

I thought the theory that Lavender and Tea Tree EOs caused hormonal problems in boys was proved to be false (can't find the reference now), but here is an article again in today's news confirming the link.

http://www.independent.co.uk/news/b...rmone-disruptor-endocrine-study-a8260326.html
_"Doctors had thought there might be similar issues with essential oils, after cases where boys who had regularly used *tea tree soaps and skin products * started developing breasts.
However the condition went away after they stopped using tea tree products. It is also appears that some people are more susceptible to the hormone-disrupting effect, the authors said."_


Does anyone have a link to the opposing article?


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## SaltedFig (Mar 18, 2018)

I cannot abide tea tree (and only use it where absolutely necessary).

Of all the poison-medicines, this one strikes me as one of the more dangerous (it is ridiculously effective, which means it is also dangerous).

Lavender is delightful fresh, but is also not so wonderful when it's become old and oxidized.

Both have disrupter abilities (and yes, it's to do with hormonal blocking).

Have a look at plastic. If you really want to worry about your boys, start looking at the plastic softeners in the plastic food containers you use.
(BPA's are directly mentioned, in your linked article)



Saffron said:


> I thought the theory that Lavender and Tea Tree EOs caused hormonal problems in boys was proved to be false (can't find the reference now), but here is an article again in today's news confirming the link.
> 
> http://www.independent.co.uk/news/b...rmone-disruptor-endocrine-study-a8260326.html
> _"Doctors had thought there might be similar issues with essential oils, after cases where boys who had regularly used *tea tree soaps and skin products * started developing breasts.
> ...


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## penelopejane (Mar 18, 2018)

BPA is also used to line cans.
Glass jars are a good option or the radical idea of limiting processed food.


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## BattleGnome (Mar 18, 2018)

I’ve seen the argument for lavender both ways. The last time I seriously looked into it the argument from the aromatherapist side was a flawed study. The claim was that they used disposable plastic Petri dishes which could have degraded with the use of EO. Neither side (that I could find) was willing to fund a study with glass Petri dishes. (Or they did and it was more fighting back and forth.) 

Adding in tea tree is new to me. Not surprised though, EOs are still super trendy and statistically someone will have an issue


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## Saffron (Mar 18, 2018)

I guess I should’ve clarified at the outset that the reason for starting this thread was to start a discussion to try and establish the facts about the safety of Lavender and tea tree oils for young children of which, in my opinion, all soap and bath + body product makers should be aware regardless of whether they sell to the public or not – especially with all the conflicting information available on the web.

It might have already been discussed previously on this forum, but new members are joining every day and not everyone browses the old threads for useful information.

Many mothers (and fathers) turn to soapmaking because they want to use natural, safe and ‘chemical-free’ products on their young children. Perhaps they watch a video on youtube or read a blog or a book and dive straight in without due diligence and research on the so-called ‘natural’ ingredients out there. They’ve heard of the mystical, magical properties of Lavender and Tea Tree and don’t think twice before using it in soaps for their children thinking it will add a calming effect at bath time or antifungal/ antibacterial properties to their hand soaps.

I myself have read conflicting reports about Lavender and was hoping a more knowledgeable member on the forum could point me in the right direction regarding the latest studies or papers on this topic in order to establish the truth of the claims.



SaltedFig said:


> Have a look at plastic. If you really want to worry about your boys, start looking at the plastic softeners in the plastic food containers you use.
> (BPA's are directly mentioned, in your linked article)



My children are adults now – so no concern for me there. I only make unfrangranced soap for the little ones in my extended family, so again no worries there.

I totally agree with you on BPA and plastics, which can be a discussion for another thread.


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## SaltedFig (Mar 18, 2018)

Latest information I could find for you ... two days ago, Chicago Endocrine Society's 100th annual meeting, 17 March 2018.

You should be able to hunt down the webcast and further information from here:
https://eurekalert.org/pub_releases/2018-03/tes-cil031418.php


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## IrishLass (Mar 18, 2018)

I'll take a look in my Essential Oil Safety Book by Tisserand/Young and report back, if someone else doesn't beat me to it (we'll be busy eating dinner here shortly).


IrishLass


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## lenarenee (Mar 18, 2018)

Eo's and children:   in the US (don't know about other countries) it is not legal to conduct medical studies on minors except under certain conditions.  There simply isn't enough credible scientific evidence out there to _responsibly_ declare any essential oil safe for children.

In fact and shockingly to me, is the fact that many  Rx and OTC products were once only approved for adult use have "slid" down in the pediatric department - _without _testing or even proof of safety or efficacy!  Yes....efficacy!  AND....they sometimes just guess at the dosage!  (educated guess yes....but still).  We know that using NSAID's can affect vascular health in adults, yet no one knows how that translates to using them on children with developing vascularity.  And have you seen the dose suggested for children on those bottles?  It's higher than suggested for adults (going by weight.)

After 20 years of using acid blockers/ppi's on babies, they're now discovering they've become adults with long term negative affects. (effects?)


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## SaltedFig (Mar 18, 2018)

Ok, I spent a little bit of time pulling together some links and data (for those who want to dig into this).



lenarenee said:


> Eo's and children:   in the US (don't know about other countries) it is not legal to conduct medical studies on minors except under certain conditions.  There simply isn't enough credible scientific evidence out there to _responsibly_ declare any essential oil safe for children.



That's pretty much the problem (as it were). I know here that the amount allowed in natural lice treatments was lowered (I can't recall from what to what, but it was on the basis that it was too strong a solution - this treatment being often used on young children of primary school age). It is a ridiculously effective treatment, and one round with tea tree will kill all adult lice and most eggs, and another round a week later to catch the eggs that survived and hatched, and the job is done. It's that good at killing insects.

Anyway, this is what I found for you:

Just to be clear, we are talking about Melaleuca alternifolia leaf oil (black tea tree is pretty toxic), specifically in the context of the effect of topical application on human hormones (only).

On one side:
Tisserand refutes the idea that tea tree is capable of crossing the skin barrier, despite it having “weak in-vitro estrogenic action in MCF-7 cells (Henley et al 2007; Nielsen 2008) on page 443 (of 2nd ed etc.)

He also questions the veracity of the reports, and suggests that there was one case of a 10 yo boy, not 3 boys, and stated that a website suggested that the testing was done by a competitor. (same page, paraphrased)

There is a substantial amount of information contained in Tisserand's reference book; tea tree information is contained across 6 pages (pages 440 to 445), however for this particular topic, he discusses reproductive toxicity across 2 detailed paragraphs at the end of page 443 across to page 444.

On the other side:
This page from the National Institute of Environmental Health Sciences seems to name the doctor who treated the 3 boys and where the study was published (in 2007) (I cannot see that Tisserand has referred to it, but I also have not checked his source material):
https://www.niehs.nih.gov/news/newsroom/releases/2007/january31/index.cfm
This page makes reference to it needing further study, that the tests were in-vitro and the boys had no other identifiable reason for their condition (calling the idea speculation), so they are not drawing concrete conclusions at that point.

Under the UN’s global Harmonised System of Classification and Labelling of Chemicals (GHS). Tea tree is classified as:
GHS Classifications:
Flammable liquid, category 3
Acute toxicity, category 4
Mildly irritating to eyes, category 2B
Irritating to skin, category 2

2015 publication (possibly the same 3 boys, 2 using cologne, 1 tested cologne with lavender), says in conclusion “Exposure to estrogenic substances, such as lavender, should be explored in children presenting with prepubertal gynecomastia/thelarche.”
https://www.ncbi.nlm.nih.gov/pubmed/26353172

Links to a lot of research (over 1,000 papers on tea tree oil):
http://www.attia.com.au/search_abstracts.php

This is interesting (related):
https://www.ncbi.nlm.nih.gov/pubmed/23211454


So, at this point in time,
a)      Tea tree and lavender can affect human hormone balances when applied to cells directly
b)      There a very small number of cases where a hormonal effect is claimed to have resulted from topical application
          (I have found a maximum of 7, or possibly 4, being either 6 boys and one woman, or more likely 3 boys and one woman)
c)      The dataset is too small at this point in time to come to concrete conclusions, ongoing/further monitoring and reporting is required.


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## lenarenee (Mar 19, 2018)

There's also another issue: _ Essential oils are not standardized._  there are dozens of suppliers/growers of tea tree/lavender/whatever. Each field/soil affects the final product, as does weather and other growing conditions. Add to that processing and distillation, storage, age, etc. and you've got several variables that can affect the purity, efficacy, strength, etc. of a bottle of eo.

 Unless you've strictly controlled all of these conditions, no 2 bottles of essential oil will be exactly the same.

(studies with drugs do not have that issue as the active ingredient is standardized.  There are a few proven rare exceptions such as the drug Dyazide where the starch filler weakened the performance of the active ingredients)


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## Saffron (Mar 19, 2018)

Doesn't seem to affect rats though.

http://journals.sagepub.com/doi/10.1177/1091581812472209
The estrogenic potential of lavender oil was evaluated in a percutaneous uterotrophic bioassay in immature female rats.....
Based on these data, lavender oil, at dosages of 20 or 100 mg/kg, was not active in the rat uterotrophic assay and gave no evidence of estrogenic activity.


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## cmzaha (Mar 19, 2018)

I make a sell a lot to Tea Tree Oil soap, using 4 oz in my batch of 60 oz oil. So each bar is getting approx 7g TTO oil and taking into account a bar will last approx 30 showers (mine do), you are only getting 0.233 grams per shower. If any in a wash off product crosses the barrier is it a very tiny amount. Please correct me if my thought on this is wrong.


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## lenarenee (Mar 19, 2018)

Its really too early to call; the study hasn't been published or peer reviewed. There are other considerations too - like perhaps these kids were affected by a combination of factors such as bpa exposure with essential oils. 

I'm glad that this will (hopefully) serve as a caution for those who have drunk the eo kool-aid and throw eo's are every ailment. But worried because I'm wondering how wise it is to you other eo's like rosemary and peppermint in soap (my favorites).  The skin does NOT absorb everything that's put on it, but we may discover that some component of eo's does get through, or even be a vehicle that permits absorption (like emu oil)


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## dixiedragon (Mar 19, 2018)

I remember somebody posting on another forum about a friend who kept losing pregnancies - turned out she was washing everyday with soap with pennyroyal EO. As soon as she ditched - bam! I assume she was just very very sensitive to the EO, but it's something to think about.


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## cmzaha (Mar 19, 2018)

dixiedragon said:


> I remember somebody posting on another forum about a friend who kept losing pregnancies - turned out she was washing everyday with soap with pennyroyal EO. As soon as she ditched - bam! I assume she was just very very sensitive to the EO, but it's something to think about.


It is something to wonder about, but then it can also be coincidence. A former neighbor of mine had several mis-carriages, finally adoped and bam she had twins the next year. So it is really hard to know.  Anyone can be sensitive to anything as we all know


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## penelopejane (Mar 19, 2018)

The first link in the first post said oestrogenic effects weren’t just linked to boys but men too. 

Isnt that linked to why girls have such large breasts these days? 

I can make myself sick with peppermint (and other EOs) in soap. I am not alone. Lots of substances are transdermal, even wash off products.


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## randycoxclemson (Mar 19, 2018)

The last I read (before today) was the counter-argument from Tisserand about the flawed 2007 anecdotal evidence from 3 boys (https://naha.org/naha-blog/neither-...ree-oil-can-be-linked-to-breast-growth-in-you).  I have to be a little wary of the new Eurekalert release as it seems to have an agenda, given that the second paragraph mentions "so-called essential oils" used by some in the US (nowhere else?) as an "alternative to medical treatment."

I'll put it up there with the alarmist info I heard about using aluminum pans or drinking milk or eating butter or using coconut oil that seems to go back and forth every decade or so.


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## IrishLass (Mar 19, 2018)

Yay- SaltedFig beat me to it (less work for me)! 

IrishLass


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## lenarenee (Mar 19, 2018)

penelopejane said:


> The first link in the first post said oestrogenic effects weren’t just linked to boys but men too.
> 
> Isnt that linked to why girls have such large breasts these days?
> 
> I can make myself sick with peppermint (and other EOs) in soap. I am not alone. Lots of substances are transdermal, even wash off products.



I have no knowledge on how transdermal eo's, fo's are or aren't - but I keep trying to find out!  

But Penelope, keep in mind that you're breathing the eo's in as well - and (if I remember Tissarand correctly) that is far more potent. 

In the US there's a wave of belief being perpetuated by poor science being spread around the internet that simply states that if it's on your skin it gets absorbed. Period. (one of the many reasons so many people want to make their own chemical free products).  This generalization is absolutely not true. Yes, there are some things that do permeate the skin but not nearly as many as people think, nor in the manner they think (instantly hits the bloodstream for example). 

I've had 3 semesters of human bio/physiology type classes and while I'm far from an expert, I do know that the integumentary system is designed to expel, not absorb. There are many barriers to protect the body from outside invaders; molecular size, polarity, protein structure, skin mantle, enzymes, etc.  (And remember, the outside layers of your skin are dead and non functioning! ) This is why people still have to wash makeup off their faces, don't get poisoned from walking through heavy traffic exhaust (the kind you can see), or drown in the shower.

Rx medication transdermal patches must us a substance to perpetuate absorption because most medications are not transdermal by themselves.

You also bring up a great question:  since the act of washing with soap and water removes germs and dirt because of electrical charge.....just how does that affect any possible absorption of soap ingredients?  Are eo's hydrophillic or phobic?
Somebody out there in the medical/science field knows these things but heck if I can find them!!!


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## DeeAnna (Mar 19, 2018)

EOs don't mix well with water => hydrophobic.


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## dxw (Mar 19, 2018)

lenarenee said:


> ... keep in mind that you're breathing the eo's in as well - and (if I remember Tissarand correctly) that is far more potent.



Excellent point. Anything you can smell is getting into your nasal passages and your lungs, and those moist membranous surfaces are far more absorptive than your skin.



lenarenee said:


> … the integumentary system is designed to expel, not absorb …



I’m not sure that the skin was ‘designed’ for that purpose, although I agree that one function of our skin is to protect against entry into the body by dangerous things. However, the skin does absorb many many things.

Why, otherwise, would big-pharma makes local-application preparations for many anti-inflammatory drugs? Looking through the published literature you will find many examples of skin absorption, including volatile oils of the types that make up many essential oils. Of course there is also the tragic use of the VX nerve agent in Malaysia, not so long ago, to further attest to skin absorption. The skin is less permeable to the more recently used Novichok 5 … if anyone cares about such semantic differences.

Locally-relevant, to me at least, eucalyptus oil (containing lots of 1,8-Cineole) penetrates through the skin … a property than has been relied upon for many millennia … as do many terpenes (ti / tea tree oil) and linalool / linalyl acetate (lavender oil).



lenarenee said:


> … the outside layers of your skin are dead and non functioning! …



The outermost layer of the outermost layer of the outermost layer of our skin contains mostly ‘dead’ cells – that is the outermost layer of the stratum corneum, which is the outermost layer of the epidermis, which is the outermost layer of the skin. The cells that flake off are mostly dead but their living progenitors are not at all far away, 10 – 40µm away varying with the different parts of your body. That’s not a lot when you think that the epidermis, outer layer of the skin, can be 1.5mm thick.

So, yes, some of the outermost 15 – 20 layers of cells in your skin are ‘dead’ but that’s only a very thin layer and below that lies a very alive and very active organ.

Now the other aspect here is that ‘dead’ does not mean non-functioning, far from it. That ‘dead’ layer has, as suggested, some very important protective functions. Those squame cells may have extruded their nuclei and a heap of their other organelles but they’re

When the outermost surface skin cells, or squames, flake-off they are usually ‘dead’. So the outermost of the outer layer of the skin is mostly made up of ‘dead’ cells, linked together in a mostly lipid support matrix and containing a heap of keratin.

The lipid support matrix, important in keeping the squames in place and relatively compact, probably provides a clue as to why many oils seem to be absorbed through the skin … and mostly aqueous substances tend to be expelled.



lenarenee said:


> Are eo's hydrophillic or phobic?



They're oils and as such are not inclined to mix well with water. They prefer their own kind. They're hydrophobic although it's an awkward term to use when you think that molecules can't really fear or love anything.



lenarenee said:


> In the US there's a wave of belief being perpetuated by poor science being spread around the internet that simply states that if it's on your skin it gets absorbed. Period. (one of the many reasons so many people want to make their own chemical free products).  This generalization is absolutely not true. Yes, there are some things that do permeate the skin but not nearly as many as people think, nor in the manner they think (instantly hits the bloodstream for example).



Yes, and no. Many things are absorbed by the skin ... and some of them very rapidly (e.g. weaponized VX nerve agent). There is an awful lot of very good science showing, and quantifying, the skin absorption of things. Of course, given the structure of the skin, it should come as no surprise that lipid type stuff tends to be better absorbed through the skin than water type stuff.

If we'd evolved in an environment of lipid-rain I suspect the outer layers of our skin would be evolved to optimally resist lipid penetration.



lenarenee said:


> ... drown in the shower.



What a dreadful image. Once I stopped chuckling I found myself agreeing completely. We live in an environment where water is the main liquid, and too much water is a bad thing, so it's no surprise that our integument has evolved with an outer layer that mostly repels water ... with the corollary consequence that drownings do not occur very often in showers.


A complex and 'charged' topic. Just my tuppence worth ... but I am currently planning not to use lavender or tea tree oil in any soaps I make for my sons, at least until I get a chance to read the latest high quality peer-reviewed published evidence.


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## SaltedFig (Mar 19, 2018)

Guess who is holding a free webinar in one week?

Robert Tisserand! 

Titled "Essential Oil Safety: Cutting through the noise"



> Essential Oil Safety with Robert Tisserand
> Learn the basic guidelines of essential oil safety from Robert Tisserand, a leading expert in the field for over 40 years.
> Cut through the noise of conflicting information, so that you can make educated decisions about what's safe and what isn't.



Registration is required.


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## lenarenee (Mar 19, 2018)

dxw said:


> Excellent point. Anything you can smell is getting into your nasal passages and your lungs, and those moist membranous surfaces are far more absorptive than your skin.
> 
> 
> 
> ...




Ooohh who are you and  how do you know all this?  What else do you know?

Real quickly here I want people to confirm/unconfirm; essential oils are not actually oils?  It was my understanding they mostly water (steam distillation eo's).

When I said the outer layer of skin was non-functioning, I meant that there was no cell function. I do know know that dead layer has its own important function - first defense line of the immune system.

Can you share any scientifically proven info you might have on what constitutents do pass through the skin?? And any other ingredients we use in soap making for that matter!  I know only a few generalizations which aren't specific enough to make me happy:  oleoresins of some plant material (like poison ivy),  some heavy metals like lead (which is why I don't use clays in soap - we have a kid in the house), acetone and paint thinner. 

But there are many things that bloggers and cottage bath product makers claim are absorbed into the body that aren't - and that is my purpose in posting. So many people think EVERYTHING is absorbed.   I long to one day have a definitive list of what does and doesn't.

And keep in mind that even while lipids generally are more adsorbable - some aren't due to size of their molecule.


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## SaltedFig (Mar 19, 2018)

Essential Oils are oil.

If you pour an EO into a glass of water, the EO will sit on top.

The distillation works by boiling/steaming the ingredients, containing and cooling the gases, then separating the oils from the hydrsols.



lenarenee said:


> Real quickly here I want people to confirm/unconfirm; essential oils are not actually oils?  It was my understanding they mostly water (steam distillation eo's).


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## dxw (Mar 19, 2018)

lenarenee said:


> What else do you know?



Not how to shut-up ... clearly 



lenarenee said:


> Real quickly here I want people to confirm/unconfirm; essential oils are not actually oils?  It was my understanding they mostly water (steam distillation eo's).



They are oils. Steam distillation is just the method used, and it's pretty good for purifying stuff that is not dissolvable in water ... such as oils.



lenarenee said:


> Can you share any scientifically proven info you might have on what constituents do pass through the skin??



If you do a little google searching, and head towards journal publications, and you will find heaps. Even easier is Google Scholar.



lenarenee said:


> So many people think EVERYTHING is absorbed.   I long to one day have a definitive list of what does and doesn't.



I think, when I am building stuff that my family will be applying to their skin, I will take a starting position that something is potentially dangerous until / unless I have some decent reason to believe otherwise. Even then I am not gonna be putting Novichok 5 in my soap, no matter how low it's skin permeability is. Call me conservative if you want.


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## dibbles (Mar 19, 2018)

SaltedFig said:


> Guess who is holding a free webinar in one week?
> 
> Robert Tisserand!
> 
> ...



Boo Hoo - I have an appointment at the time this is happening. If anyone is able to join the webinar, I hope the information is passed along. Not a subtle hint, but I am very interested so it would be very much appreciated.


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## lenarenee (Mar 20, 2018)

SaltedFig said:


> Essential Oils are oil.
> 
> If you pour an EO into a glass of water, the EO will sit on top.
> 
> The distillation works by boiling/steaming the ingredients, containing and cooling the gases, then separating the oils from the hydrsols.



This could explain why essential oils spilled straight on skin need to be cleaned off with carrier, not water?


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## lenarenee (Mar 20, 2018)

dxw said:


> Not how to shut-up ... clearly
> 
> 
> 
> ...



Hey, when someone has something to contribute to the knowledge base here - we don't want them to shut up.

So you are not physiologist or dermatological expert?  (sadly, my search continues)

I've done plenty of Googling and found plenty of pubmed and other publications.   Many with that ubiquitous line that says "further research is indicated" - among others.   All too often I find one study than negates another and many that are just wholly way beyond  me. I don't have the knowledge to muddle through all of that so I want to find qualified people who can. 

I don't blame you at all for being conservative.


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## SaltedFig (Mar 20, 2018)

Lenarenee, look at how emu oil works (transferring across the skin barrier), and also look at why the short chain of coconut soap can get between the outer layer of skin cells and irritate.
(Skin type/genetic structure makes a difference, which is why coconut soap is irritating to most people, but not everyone).



lenarenee said:


> This could explain why essential oils spilled straight on skin need to be cleaned off with carrier, not water?



I hadn't heard that directly, but yes, plain cold water would just roll off (warm, soapy water works and is better IMHO, if your purpose is to remove the essential oil - wipe and wash).

An example of oil being used as a solvent for essential oils is the use of sweet almond oil as a carrier oil for essential oils in massage therapy.
The sweet almond oil is the solvent for the essential oil in this instance. Carrier oils are solvent oils. In the instance of a massage oil, the solvent oil is chosen for it's use on skin (sweet almond oil is lovely as a massage oil).
For burning, the carrier oil would be an oil that burns well (think olive oil lamps, as one example).
Resins and waxes can also be dissolved in oils, and so you can have polishes with essential oils in them too.


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## The Efficacious Gentleman (Mar 20, 2018)

Is that really what sodium cocoate does? I thought that it just stripped the natural oils from the skin, causing dryness and eventually irritation


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## Saffron (Mar 20, 2018)

lenarenee said:


> some heavy metals like lead (which is why I don't use clays in soap - we have a kid in the house), acetone and paint thinner.


Interesting point that. Does it apply to all clays? Many use kaolin in baby soaps.


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## SaltedFig (Mar 20, 2018)

The Efficacious Gentleman said:


> Is that really what sodium cocoate does? I thought that it just stripped the natural oils from the skin, causing dryness and eventually irritation





SaltedFig said:


> ..., and also look at why the short chain of coconut soap can get between the outer layer of skin cells and irritate.



Coconut soap (sodium cocoate) is a superb surfactant and will remove natural oils from skin (or strip the oils, as you say) and can dry out and irritate skin.

Sodium laurate (or the sodium salt of the fatty acid "lauric acid", which I referred to as the short chain of coconut soap as it constitutes roughly 1/2 the fatty acid profile of coconut oil) is a C-12 surfactant.

C12 soaps are of a molecular size able to penetrate skin. The depth and impact of skin penetration has a multitude of inputs (exposure time, pH, number of exposures over time, moisture levels in the skin and temperatures are known inputs). I am of the personal belief that genetic skin structure is also an input (to the skin permeability of C-12 surfactants).

I find the older studies uncomfortable reading, but a curious thing I noticed in a 1959 article "When 3 ml quantities quantities of 0.0005 M buffered sodium laurate solutions are held in contact with the normal skin of an individual who has no known clinical reaction to soap, erythema and pruritus develop during the first 6 hours of contact where the pH of the solution is 7.5, but there is no apparent reaction when the solution is pH is 9.5." In these earlier studies, it was believed that the mechanism of skin penetration was entirely lipid based, but even so, this observation on the pH is still intriguing.

Later studies pointed to the skin being able to shift the pH of the penetrating sodium laurate, and lowering it. The mechanisms were studied further, and a lot of studies shifted a few decades ago to another C-12 surfactant.

The whole thing is more complex that I currently have been able to wrap my head around, but this one from 2012 is detailed and relatively easy to read:
"Cleansing Formulations That Respect Skin Barrier Integrity"
It contains useful information on how the molecular size of the surfactant affects skin permeability (albeit in the context of another C-12 surfactant).


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## lenarenee (Mar 20, 2018)

Saffron said:


> Interesting point that. Does it apply to all clays? Many use kaolin in baby soaps.



Saffron, at the time I did my research about 4 years  ago, the sources I found stated the all clays will  contain heavy metals to at least a small degree, lead being one of them. Since lead and other heavy metals can be absorbed through the skin and our girl was 6 at the time, I just gave up on clay. Lead exposure accumulates in the body over time.


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