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Etude House 0.2 Therapy Air Mask - Snail

0.2 Therapy Air Mask - Snail

The mask containing snail secretion filtrate makes your skin texture smooth, radiant and elastic by strengthening skin barrier.
Uploaded by: symphonie9 on

Highlights

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Ingredient name what-it-does irr., com. ID-Rating
Water solvent
Dipropylene Glycol solvent
Caprylic/Capric Triglyceride emollient
Glycerin skin-identical ingredient, moisturizer/​humectant 0, 0 superstar
Methylpropanediol solvent
Sorbitan Stearate emulsifying 1, 0
Butylene Glycol moisturizer/​humectant, solvent 0, 1
1,2-Hexanediol solvent
Snail Secretion Filtrate(2,500Ppm) antioxidant, moisturizer/​humectant goodie
Sorbitan Sesquioleate emulsifying 0, 0-1
Arginine skin-identical ingredient goodie
Acrylates/C10-30 Alkyl Acrylate Crosspolymer viscosity controlling
Hydroxyethylcellulose viscosity controlling
Sucrose Cocoate emulsifying
Coptis Japonica Root Extract soothing, antioxidant goodie
Zingiber Officinale (Ginger) Root Extract antioxidant, soothing goodie
Camellia Sinensis Leaf Extract antioxidant, soothing goodie
Glycyrrhiza Glabra (Licorice) Root Extract soothing, skin brightening superstar
Adenosine cell-communicating ingredient goodie
Dehydroacetic Acid preservative
Dipotassium Glycyrrhizate soothing, moisturizer/​humectant goodie
Disodium EDTA chelating
Boswellia Serrata Gum perfuming
Sodium Hyaluronate skin-identical ingredient, moisturizer/​humectant 0, 0 goodie
Hydrogenated Lecithin emollient, emulsifying goodie
Phytosteryl/Octyldodecyl Lauroyl Glutamate emollient goodie
Eucalyptus Globulus Leaf Oil perfuming, antimicrobial/​antibacterial icky
Ceramide NP skin-identical ingredient goodie
Centella Asiatica Extract soothing, antioxidant, moisturizer/​humectant goodie
Citrus Nobilis (Mandarin Orange) Oil icky
Lavandula Angustifolia (Lavender) Oil antimicrobial/​antibacterial, perfuming icky
Pinus Palustris Oil perfuming
Juniperus Mexicana Oil
Citrus Limon (Lemon) Fruit Extract
Limonene perfuming, solvent icky

Etude House 0.2 Therapy Air Mask - Snail
Ingredients explained

Also-called: Aqua | What-it-does: solvent

Good old water, aka H2O. The most common skincare ingredient of all. You can usually find it right in the very first spot of the ingredient list, meaning it’s the biggest thing out of all the stuff that makes up the product. 

It’s mainly a solvent for ingredients that do not like to dissolve in oils but rather in water. 

What-it-does: solvent

A clear, colorless liquid that works as a solvent and viscosity decreasing ingredient. It also has great skin-moisturizing abilities. 

What-it-does: emollient

A super common emollient that makes your skin feel nice and smooth. It comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. It’s a nice ingredient that just feels good on the skin, is super well tolerated by every skin type and easy to formulate with. No wonder it’s popular. 

Glycerin - superstar
Also-called: Glycerol | What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0
  • A natural moisturizer that’s also in our skin
  • A super common, safe, effective and cheap molecule used for more than 50 years
  • Not only a simple moisturizer but knows much more: keeps the skin lipids between our skin cells in a healthy (liquid crystal) state, protects against irritation, helps to restore barrier
  • Effective from as low as 3% with even more benefits for dry skin at higher concentrations up to 20-40%
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

What-it-does: solvent

It's a type of glycol that - according to the manufacturer - is an extremely good replacement for other glycols like propylene or butylene glycol. Its main job is to be a solvent, but it has also very good antimicrobial properties and acts as a true preservative booster. Also helps with skin hydration without stickiness or tacky feel.

What-it-does: emulsifying | Irritancy: 1 | Comedogenicity: 0

A popular, vegetable-derived oil-loving emulsifier that helps water to mix with oil. In itself, it is suitable for water-in-oil emulsions (where water droplets are dispersed in oil), but it is more often used as a co-emulsifier next to other, water-loving emulsifiers. 

Chemically speaking, it comes from the attachment of sorbitan (a dehydrated sorbitol (sugar) molecule) with the fatty acid Stearic Acid, that creates a partly water (the sorbitan part) and partly oil soluble (stearic part) molecule. 

What-it-does: moisturizer/humectant, solvent | Irritancy: 0 | Comedogenicity: 1

Butylene glycol, or let’s just call it BG, is a multi-tasking colorless, syrupy liquid. It’s a great pick for creating a nice feeling product.  

BG’s main job is usually to be a solvent for the other ingredients. Other tasks include helping the product to absorb faster and deeper into the skin (penetration enhancer), making the product spread nicely over the skin (slip agent), and attracting water (humectant) into the skin.

What-it-does: solvent

A really multi-functional helper ingredient that can do several things in a skincare product: it can bring a soft and pleasant feel to the formula, it can act as a humectant and emollient, it can be a solvent for some other ingredients (for example it can help to stabilize perfumes in watery products) and it can also help to disperse pigments more evenly in makeup products. And that is still not all: it can also boost the antimicrobial activity of preservatives

Also-called: Snail Slime, Snail Mucin | What-it-does: antioxidant, moisturizer/humectant

If you are into the K-Beauty trend, you must have bumped into snail slime like a thousand times. Korean brands love the ingredient and tout it for its miraculous repair and hydration properties. It's claimed to be able to repair everything from dry patches, acne breakouts to signs of aging and we are happy to say that it might be just true.

So snail slime is the yucky stuff that snails (in cosmetics the secretion of Cornu Aspersum, the garden snail is used) produce when they are in stress (it's not the same as the one they secret to be able to move nicely and smoothly). As the cosmetic chemists at the Beauty Brains blog write, "chemically speaking, snail slime is a complex mixture of proteoglycans, glycosaminoglycans, glycoprotein enzymes, hyaluronic acid, copper peptides, antimicrobial peptides and trace elements including copper, zinc, and iron."   English translation equals it's loaded with a bunch of good-for-the-skin stuff.

What-it-does: emulsifying | Irritancy: 0 | Comedogenicity: 0-1

A mainly oil loving molecule that helps water and oil to mix nicely, aka emulsifier. In itself, it can create water-in-oil emulsions (when water droplets are dispersed in oil), but it is used mostly next to water-loving emulsifiers to create nice and smooth oil-in-water creams.  It can also function as a wetting and dispersing agent helping insoluble particles such as color pigments or inorganic sunscreens (zinc/titanium dioxide) to disperse nice and even in liquids.  

Chemically speaking, this molecule is "halfway" between Sorbitan Oleate and Sorbitan Trioleate, meaning that it is also an attachment of sorbitan (a dehydrated sorbitol (sugar) molecule) with the unsaturated fatty acid Oleic Acid, but in a ratio of 2:3 hence the "Sesqui" part in the molecule's name. 

Arginine - goodie

A semi-essential (infants cannot synthesize it, but adults can) amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor, a skin hydrator and might also help to speed up wound healing

Arginine usually has a positive charge (cationic) that makes it substantive to skin and hair (those are more negatively charged surfaces) and an excellent film former.  Thanks to the positive charge, it also creates a complex with AHAs (AHAs like to lose a hydrogen ion and be negatively charged, so the positive and the negative ions attract each other) that causes a "time-release AHA effect" and reduces the irritation associated with AHAs

Though its long name does not reveal it, this polymer molecule (big molecule from repeated subunits or monomers) is a relative to the super common, water-loving thickener, Carbomer. Both of them are big molecules that contain acrylic acid units, but Acrylates/C10-30 Alkyl Acrylate Crosspolymer also contains some other monomers that are hydrophobic, i.e. water-hating. 

This means that our molecule is part water- and part oil-loving, so it not only works as a thickener but also as an emulsion stabilizer. It is very common in gel-type formulas that also contain an oil-phase as well as in cleansers as it also works with most cleansing agents (unlike a lot of other thickeners). 

Also-called: HEC | What-it-does: viscosity controlling, emulsion stabilising

A nice little helper ingredient that can thicken up cosmetic products and create beautiful gel formulas. It's derived from cellulose, the major component of the cell wall of green plants. It is compatible with most co-ingredients and gives a very good slip to the formulas. 

What-it-does: emulsifying

We don't have description for this ingredient yet.

Also-called: Japanese Goldthread Root Extract | What-it-does: soothing, antioxidant

The extract coming from the root of the traditional medicinal herb, Coptis Japonica or Japanese Goldthread. The plant is used traditionally in East Asia for its anti-inflammatory, antioxidant and antimicrobial abilities.

Other than that, there is also an abstract from the International Journal of Cosmetic Science that found Coptis Japonica Root Extract and its active component called berberine to show potent inhibition of triglyceride (aka fat) accumulation and subcutaneous preadipocytes (the cells that become later fat cells) differentiation meaning that Goldthread Extract might also be useful in slimming and anti-cellulite products.

Also-called: Ginger Root Extract | What-it-does: antioxidant, soothing

The extract coming from ginger, the lovely spice that we all know from the kitchen. It is also a medicinal plant used both in Chinese and Ayurvedic medicine for pretty much everything you can imagine (muscular pain, sore throat, nausea, fever or cramps,  just to give a few examples).

As for ginger and skincare, the root extract contains the biologically active component called gingerol that has potent antioxidant and anti-inflammatory properties. Combined with Bisabololthe duo works synergistically to sooth the skin and take down redness. 

Also-called: Green Tea | What-it-does: antioxidant, soothing
  • Green tea is one of the most researched natural ingredients
  • The active parts are called polyphenols, or more precisely catechins (EGCG being the most abundant and most active catechin)
  • There can be huge quality differences between green tea extracts. The good ones contain 50-90% catechins (and often make the product brown and give it a distinctive smell)
  • Green tea is proven to be a great antioxidant, UV protectant, anti-inflammatory, anticarcinogenic and antimicrobial
  • Because of these awesome properties green tea is a great choice for anti-aging and also for skin diseases including rosacea, acne and atopic dermatitis
Read all the geeky details about Camellia Sinensis Leaf Extract here >>

Also-called: Licorice Root;Glycyrrhiza Glabra Root Extract | What-it-does: soothing, skin brightening

You might know licorice as a sweet treat from your childhood, but it's actually a legume that grows around the Mediterranean Sea, the Middle East, central and southern Russia. It's sweet and yellow and not only used for licorice all sorts but it's also a skincare superstar thanks to two magic properties:

Nr. 1 magic property is that it has skin-lightening or to say it another way depigmenting properties. The most active part is called glabridin. The topical application (meaning when you put it on your face) of 0.5% glabridin was shown to inhibit UVB caused pigmentation of guinea pigs. Another study even suggested that licorice is more effective than the gold standard skin-lightening agent hydroquinone. All in all, licorice is considered to be one of the safest skin lightening agents with the fewest side effects.

Adenosine - goodie

Adenosine is an important little compound in our body that has a vital cell-signalling role. Research on smearing it on our face is also promising and shows so far a couple of things:

  • It can help with wound healing
  • It’s a good anti-inflammatory agent
  • It might even help with skin’s own collagen production and improve skin firmness and elasticity
  • It helps with barrier repair and protection
  • It might be even useful for the hair helping with hair thickness and hair growth
Also-called: Geogard 111A | What-it-does: preservative

A helper ingredient that helps to make the products stay nice longer, aka preservative. It works mainly against fungi and has only milder effect against bacteria. 

It is Ecocert and Cosmos approved, works quite well at low concentrations (0.1-0.6%) and is popular in natural products.

Also-called: Licorice | What-it-does: soothing, moisturizer/humectant

The salt form of one of the main anti-inflammatory ingredients in the licorice plant, monoammonium glycyrrhizinate. It’s a yellowish powder with a nice sweet smell. 

It’s used mainly for its soothing and anti-inflammatory properties, but according to manufacturer info, it’s also sebum regulating so it's a perfect ingredient for problem skin products. 

What-it-does: chelating

Super common little helper ingredient that helps products to remain nice and stable for a longer time. It does so by neutralizing the metal ions in the formula (that usually get into there from water) that would otherwise cause some not so nice changes.

It is typically used in tiny amounts, around 0.1% or less.

What-it-does: perfuming

We don't have description for this ingredient yet.

What-it-does: skin-identical ingredient, moisturizer/humectant | Irritancy: 0 | Comedogenicity: 0

It’s the - sodium form - cousin of the famous NMFhyaluronic acid (HA). If HA does not tell you anything we have a super detailed, geeky explanation about it here.  The TL; DR version of HA is that it's a huge polymer (big molecule from repeated subunits) found in the skin that acts as a sponge helping the skin to hold onto water, being plump and elastic. HA is famous for its crazy water holding capacity as it can bind up to 1000 times its own weight in water.

As far as skincare goes, sodium hyaluronate and hyaluronic acid are pretty much the same and the two names are used interchangeably. As cosmetic chemist kindofstephen writes on reddit  "sodium hyaluronate disassociates into hyaluronic acid molecule and a sodium atom in solution". 

What-it-does: emollient, emulsifying

It's the chemically chopped up version of normal lecithin. Most often it's used to create liposomes and to coat and stabilize other ingredients. 

What-it-does: emollient

An amino-acid (glutamic acid) derived molecule that is claimed to form lamellar liquid crystals similar to the ones formed in the skin between skin cells (called lipid bilayer). The lipid bilayer is like the "mortar" between our skin cells ("the bricks") and is super important for a healthy skin barrier and keeping water in the upper layers of the skin. 

So Phytosteryl/Octyldodecyl Lauroyl Glutamate is a skin-lipid-like material that makes your skin nice and smooth (emollient) and keeps your skin hydrated. According to the manufacturer's tests, it is more effective than petrolatum in promoting the recovery of damaged skin and improving rough skin conditions.

Also-called: Eucalyptus Essential Oil | What-it-does: perfuming, antimicrobial/antibacterial

The essential oil created by steam distilling the leaves of the Eucalyptus tree. It's a colorless, pale yellow oil with a camphoraceous aroma used traditionally in vapor rubs to treat coughs. Its name-giving main component is eucalyptol (also called 1,8-cineole, 80-91%) that has significant antibacterial and expectorant properties.   

Among essential oils, Eucalyptus Globulus counts as rather non-sensitising with an EU sensitizer total of 5% (due to limonene). However, if your skin is super-sensitive or you are allergic to fragrances, it is still better to avoid it. 

Ceramide NP - goodie
Also-called: Ceramide 3 | What-it-does: skin-identical ingredient

One of the many types of ceramides that can be found naturally in the upper layer of the skin. Ceramides make up about 50% of the goopy stuff that's between our skin cells and play a super important role in having a healthy skin barrier and keeping the skin hydrated. It works even better when combined with its pal, Ceramide 1.

We wrote way more about ceramides at ceramide 1, so click here to know more.

Also-called: Gotu Kola, Tiger Grass | What-it-does: soothing, antioxidant, moisturizer/humectant

Centella Asiatica - or sometimes also called Gotu Kola or Cica - has been used in folk medicine for hundreds of years. It’s traditionally used to improve small wounds, burns and scratches and it’s also a well known anti-inflammatory agent for eczema.

Recently science has taken an interest in Gotu Kola as well and it turns out it really has many active compounds with several benefits. Just for hard-core geeks, the main biologically active compounds are pentacyclic triterpenoid saponins called asiaticoside, madecassoside, asiatic and madecassic acid (also called centellosides).

Also-called: Mandarin Orange Oil

The essential oil coming from the whole plant of the Mandarin Orange. In general, the main component of citrus oils is limonene, a super common fragrant ingredient that makes everything smell nice (but counts as a frequent skin sensitizer).  The majority of the essential oil is in the peel, but the leaf also contains some with slightly different chemical composition. 

Both the peel and the leaf oil contains some phototoxic compounds (the leaf oil contains methyl-N-methyl anthranilate), so it's a good idea not to use Mandarin Orange Oil containing products during the day.

Also-called: Lavender Essential Oil | What-it-does: antimicrobial/antibacterial, perfuming

We have to start by writing how fascinated we are by the amazing lavender fields of Provance and we do love pretty much everything about lavender: its look, its color, its scent.... but, when it comes to skincare, lavender is a questionable ingredient that you probably do not want in your skincare products.

First, let us start with the pros: it has a lovely scent, so no wonder that it is popular as a fragrance ingredient in natural products wanting to be free from synthetic fragrances but still wanting to smell nice. The scent of lavender is famous for having calming and relaxing properties and some smallish scientific studies do support that. Inhaled volatile compounds seem to have a soothing effect on the central nervous system and studies have shown that lavender aromatherapy can improve patient's anxiety and experience in hospitals.   

What-it-does: perfuming

We don't have description for this ingredient yet.

We don't have description for this ingredient yet.

Also-called: Lemon Fruit Extract

If life gives the cosmetic industry lemon, it makes lemon fruit extract.  As to why, we can write here extremely similar things to our shiny description of orange fruit extract.  Being both of them citruses, they contain very similar active compounds with very similar (potential) effects on the skin. 

Just like orange fruit, lemon fruit also contains citric acid so it is commonly used as a natural, mild exfoliating agent. If this is the case, it is usually combined with other AHA containing fruit extracts such as bilberrysugar cane, orange, and sugar maple in a super popular ingredient mix trade named ACB Fruit Mix.

Limonene - icky
What-it-does: perfuming, solvent, deodorant

A super common and cheap fragrance ingredient. It's in many plants, e.g. rosemary, eucalyptus, lavender, lemongrass, peppermint and it's the main component (about 50-90%) of the peel oil of citrus fruits.

It does smell nice but the problem is that it oxidizes on air exposure and the resulting stuff is not good for the skin. Oxidized limonene can cause allergic contact dermatitis and counts as a frequent skin sensitizer

You may also want to take a look at...

what‑it‑does solvent
Normal (well kind of - it's purified and deionized) water. Usually the main solvent in cosmetic products. [more]
what‑it‑does solvent
A clear, colorless liquid that works as a solvent and viscosity decreasing ingredient. It also has great skin-moisturizing abilities.  [more]
what‑it‑does emollient
A very common emollient that makes your skin feel nice and smooth. Comes from coconut oil and glycerin, it’s light-textured, clear, odorless and non-greasy. [more]
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
A real oldie but a goodie. Great natural moisturizer and skin-identical ingredient that plays an important role in skin hydration and general skin health. [more]
what‑it‑does solvent
A type of glycol. Its main job is to be a solvent, but it has also very good antimicrobial properties and acts as a true preservative booster. [more]
what‑it‑does emulsifying
irritancy, com. 1, 0
A popular, vegetable-derived oil-loving emulsifier that helps water to mix with oil. In itself, it is suitable for water-in-oil emulsions (where water droplets are dispersed in oil), but it is more often used as a co-emulsifier next to other, water-loving emulsifiers.  Chemically speaking, it comes from the attachment of sorbitan (a dehydrated sorbitol (sugar) molecule) with the fatty [more]
what‑it‑does moisturizer/humectant | solvent
irritancy, com. 0, 1
An often used glycol that works as a solvent, humectant, penetration enhancer and also gives a good slip to the products. [more]
what‑it‑does solvent
A multi-functional helper ingredient that acts as a humectant and emollient. It's also a solvent and can boost the effectiveness of preservatives. [more]
what‑it‑does antioxidant | moisturizer/humectant
If you are into the K-Beauty trend, you must have bumped into snail slime like a thousand times. Korean brands love the ingredient and tout it for its miraculous repair and hydration properties. [more]
what‑it‑does emulsifying
irritancy, com. 0, 0-1
A mainly oil loving molecule that helps water and oil to mix nicely, aka emulsifier. In itself, it can create water-in-oil emulsions (when water droplets are dispersed in oil), but it is used mostly next to water-loving emulsifiers to create nice and smooth oil-in-water creams.  It can also function as a wetting and dispersing agent helping insoluble particles such as color pigments [more]
what‑it‑does skin-identical ingredient
An amino acid that is one of the primary building blocks of hair keratin and skin collagen. It's a natural moisturizing factor and might also help to speed up wound healing.  [more]
what‑it‑does viscosity controlling
A common helper ingredient that stabilizes emulsions and helps to thicken up products. [more]
what‑it‑does viscosity controlling
A nice little helper ingredient that can thicken up cosmetic products and create beautiful gel formulas. It's derived from cellulose, the major component of the cell wall of green plants. [more]
what‑it‑does emulsifying
what‑it‑does soothing | antioxidant
The extract coming from the root of the traditional medicinal herb, Coptis Japonica or Japanese Goldthread. The plant is used traditionally in East Asia for its anti-inflammatory, antioxidant and antimicrobial abilities. Other than that, there is also an abstract from the International Journal of Cosmetic Science that found Coptis Japonica Root Extract and its active component called b [more]
what‑it‑does antioxidant | soothing
Ginger extract that has antioxidant and soothing properties. It is also known to increase blood circulation and thus have a toning effect. [more]
what‑it‑does antioxidant | soothing
Green Tea - one of the most researched natural ingredients that contains the superstar actives called catechins. It has proven antioxidant, anti-inflammatory, antimicrobial and anticarcinogenic properties. [more]
what‑it‑does soothing | skin brightening
You might know licorice as a sweet treat from your childhood, but it's actually a legume that grows around the Mediterranean Sea, the Middle East, central and southern Russia. [more]
what‑it‑does cell-communicating ingredient
An important compound in our body that has a vital cell-signalling role. It is wound healing, anti-inflammatory and can help with barrier repair. [more]
what‑it‑does preservative
A preservative that works mainly against fungi and has only milder effect against bacteria. Popular in natural products.  [more]
what‑it‑does soothing | moisturizer/humectant
The salt form of one of the main anti-inflammatory ingredients in the licorice plant, monoammonium glycyrrhizinate. It’s a yellowish powder with a nice sweet smell.  It’s used mainly for its soothing and anti-inflammatory properties, but according to manufacturer info, it’s also sebum regulating so it' [more]
what‑it‑does chelating
Super common little helper ingredient that helps products to remain nice and stable for a longer time. It does so by neutralizing the metal ions in the formula (that usually get into there from water) that would otherwise cause some not so nice changes. [more]
what‑it‑does perfuming
what‑it‑does skin-identical ingredient | moisturizer/humectant
irritancy, com. 0, 0
It's the salt form of famous humectant and natural moisturizing factor, hyaluronic acid. It can bind huge amounts of water and it's pretty much the current IT-moisturizer. [more]
what‑it‑does emollient | emulsifying
It's the chemically chopped up version of normal lecithin. Most often it's used to create liposomes and to coat and stabilize some other ingredient. 
what‑it‑does emollient
An amino-acid (glutamic acid) derived molecule that is claimed to form lamellar liquid crystals similar to the ones formed in the skin between skin cells (called lipid bilayer). [more]
what‑it‑does perfuming | antimicrobial/antibacterial
The essential oil created by steam distilling the leaves of the Eucalyptus tree. It's a colorless, pale yellow oil with a camphoraceous aroma used traditionally in vapor rubs to treat coughs. [more]
what‑it‑does skin-identical ingredient
Ceramides make up 50% of the goopy stuff that's between our skin cells and play a super important role in having a healthy skin barrier and keeping the skin hydrated.  [more]
what‑it‑does soothing | antioxidant | moisturizer/humectant
Centella Asiatica - or sometimes also called Gotu Kola or Cica - has been used in folk medicine for hundreds of years. It’s traditionally used to improve small wounds, burns and scratches and it’s also a well known anti-inflammatory agent for eczema. Recently science has taken an interest in Gotu Kola as well and it turns out it really has many active compounds with several benefits. [more]
Mandarin Orange essential oil - Contains the fragrant component limonene and makes things smell nice. [more]
what‑it‑does antimicrobial/antibacterial | perfuming
Lavender - essential oil with a calming scent and antimicrobial properties. Contains fragrant components (linalyl acetate - 50% and linalool - 35%) and might be cytotoxic from 0.25%. [more]
what‑it‑does perfuming
If life gives the cosmetic industry lemon, it makes lemon fruit extract.  As to why, we can write here extremely similar things to our shiny description of orange fruit extract.  Being both of them citruses, they contain very similar active compounds with very similar (potential) effects on the skin.  [more]
what‑it‑does perfuming | solvent
A super common fragrance ingredient found naturally in many plants including citrus peel oils, rosemary or lavender. It autoxidizes on air exposure and counts as a common skin sensitizer. [more]