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Peter Thomas Roth Therapeutic Sulfur Mask

Therapeutic Sulfur Mask

A 10 percent sulfur mask that clears acne, absorbs oil, and cleanses pores.
Uploaded by: blumi on

Peter Thomas Roth Therapeutic Sulfur Mask
Ingredients explained

Sulfur (10%) - goodie
What-it-does: anti-acne, antimicrobial/antibacterial | Irritancy: 0 | Comedogenicity: 0-3

A yellowish element that smells of rotten eggs and it might be familiar to you from the periodic table (has the symbol S in there).  It has a long history of medicinal use thanks to its antifungal, antibacterial and keratolytic activity.   It used to be a very common ingredient in the treatment of inflammation-related skin diseases such as acne, rosacea and seborrheic dermatitis, however, due to its malodorousness, it is less popular nowadays. 

Sulfur's precise mechanism of action is not known, but we do know that its effectiveness depends on its direct interaction with the skin surface, meaning the smaller the particle size, the better the effect. The United States Pharmacopeia lists two types of sulfur, sublimed and precipitated. The latter one has a smaller particle size and counts as a superior version. 

Also-called: Aqua;Water | 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. 

Bentonite - goodie
Also-called: Type of clay | What-it-does: viscosity controlling, absorbent/mattifier, emulsion stabilising | Irritancy: 0 | Comedogenicity: 0

When it comes to oil-absorbing clay masks, bentonite will probably be one of the first ingredients on the INCI list. Technically bentonite clay is mostly montmorillonite + something else, and thanks to the something else bit, bentonite comes in different types and colors

The color depends on the mineral content of the clay: white bentonite is rich in boron and fluoride, yellow is rich in manganese and zinc, green is rich in copper, zinc, and manganese and the pink clay is rich in boron.

Kaolin - goodie
Also-called: Type of clay, China clay | What-it-does: colorant, absorbent/mattifier, abrasive/scrub | Irritancy: 0 | Comedogenicity: 0

Kaolin is a type of clay or to be precise, a naturally occurring hydrous aluminum silicate. When you hear clay, you probably think of a muddy greenish-black mess, but that one is bentonite, and this one is a fine, white powder. It is so white that it's also often used, in small amounts, as a helper ingredient to give opacity and whiteness to the cosmetic formulas.

As a clay, it's absorbent and can suck up excess sebum and gunk from your skin, but less so than the more aggressive bentonite. As it's less absorbent, it's also less drying and gentler on the skin, so it's ideal for dry and sensitive skin types.  

What-it-does: moisturizer/humectant, solvent, viscosity controlling | Irritancy: 0 | Comedogenicity: 0
  • It's a helper ingredient that improves the freeze-thaw stability of products
  • It's also a solvent, humectant and to some extent a penetration enhancer
  • It has a bad reputation among natural cosmetics advocates but cosmetic scientists and toxicology experts do not agree (read more in the geeky details section)
Read all the geeky details about Propylene Glycol here >>

What-it-does: absorbent/mattifier, abrasive/scrub | Irritancy: 0 | Comedogenicity: 1

Talc is the major component of most powder makeup products (think face powder, eyeshadows, and blushers) that usually contain it up to 70%. Its two winning properties that make it very suitable for this role is its outstanding spreadability for a smooth application and its low covering power, aka translucency to avoid clown-like effects.

Chemically speaking, it is a clay mineral (hydrated magnesium silicate) that is mined in several countries. The drawback of mined minerals is potential impurities and the version used in cosmetics has to be white (not gray like cheaper grades), free from asbestos, sterilized and have thin plates for a maximum slip. 

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 at higher concentrations up to 20-40% (around 10% is a good usability-effectiveness sweet spot)
  • High-glycerin moisturizers are awesome for treating severely dry skin
Read all the geeky details about Glycerin here >>

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

Aloe Vera is one of today’s magic plants. It does have some very nice properties indeed, though famous dermatologist Leslie Baumann warns us in her book that most of the evidence is anecdotal and the plant might be a bit overhyped.

What research does confirm about Aloe is that it’s a great moisturizer and has several anti-inflammatory (among others contains salicylates, polysaccharides, magnesium lactate and C-glucosyl chromone) as well as some antibacterial components. It also helps wound healing and skin regeneration in general. All in all definitely a goodie. 

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

When it comes to sunscreen agents, Zinc Oxide is pretty much in a league of its own. It's a physical (or inorganic) sunscreen that has a lot in common with fellow inorganic sunscreen Titanium Dioxide (TiO2) but a couple of things make it superior even to TiO2.

If physical sunscreens don't tell you anything, go ahead and read about the basics here. Most of what we wrote about Titanium Dioxide is also true for Zinc Oxide so we will focus here on the differences. 

What-it-does: emulsifying, surfactant/cleansing | Irritancy: 0 | Comedogenicity: 0

It's a common little helper ingredient that helps water and oil to mix together. Also, it can help to increase the solubility of some other ingredients in the formula. 

Also-called: Titanium Dioxide/Ci 77891;Ci 77891 | What-it-does: colorant | Irritancy: 0 | Comedogenicity: 0

Ci 77891 is the color code of titanium dioxide. It's a white pigment with great color consistency and dispersibility.

What-it-does: viscosity controlling, emulsion stabilising | Irritancy: 0 | Comedogenicity: 1

A big molecule created from repeated subunits (a polymer of acrylic acid) that magically converts a liquid into a nice gel formula.  It usually has to be neutralized with a base (such as sodium hydroxide) for the thickening to occur and it creates viscous, clear gels that also feel nice and non-tacky on the skin. No wonder, it is a very popular and common ingredient. Typically used at 1% or less in most formulations.

Also-called: Fragrance, Parfum;Parfum/Fragrance | What-it-does: perfuming

Exactly what it sounds: nice smelling stuff put into cosmetic products so that the end product also smells nice. Fragrance in the US and parfum in the EU is a generic term on the ingredient list that is made up of 30 to 50 chemicals on average (but it can have as much as 200 components!). 

If you are someone who likes to know what you put on your face then fragrance is not your best friend - there's no way to know what’s really in it.  

Also-called: lye | What-it-does: buffering

The unfancy name for it is lye. It’s a solid white stuff that’s very alkaline and used in small amounts to adjust the pH of the product and make it just right. 

For example, in case of AHA or BHA exfoliants, the right pH is super-duper important, and pH adjusters like sodium hydroxide are needed.  

What-it-does: preservative

An antimicrobial preservative that helps your products not to go wrong too quickly. It works especially well against bacteria, specifically gram-negative species, yeast, and mold.

Somewhat controversial, it belongs to an infamous family of formaldehyde-releasers. That is, it slowly breaks down to form formaldehyde when it is added to a formula. We have written more about formaldehyde-releasing preservatives and the concerns around them at Dmdm Hydantoin, but do not get too scared, those are more theories than proven facts.

What-it-does: preservative | Irritancy: 0 | Comedogenicity: 0

The most common type of feared-by-everyone-mostly-without-scientific-reason parabens. It's a cheap, effective and well-tolerated ingredient to make sure the cosmetic formula does not go wrong too soon

Apart from the general controversy around parabens (we wrote about it more here), there is a 2006 in-vitro (made in the lab not on real people) research about methylparaben (MP) showing that when exposed to sunlight, MP treated skin cells suffered more harm than non-MP treated skin cells. The study was not done with real people on real skin but still - using a good sunscreen next to MP containing products is a good idea. (Well, in fact using a sunscreen is always a good idea. :))

What-it-does: preservative, perfuming | Irritancy: 0 | Comedogenicity: 0

A very common type of feared-by-everyone-mostly-without-scientific-reason parabens. It's a cheap, effective and well-tolerated ingredient to make sure the cosmetic formula does not go wrong too soon.

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what‑it‑does anti-acne | antimicrobial/antibacterial
irritancy, com. 0, 0-3
A yellowish element that smells of rotten eggs and it might be familiar to you from the periodic table (has the symbol S in there).  It has a long history of medicinal use thanks to its antifungal, antibacterial and keratolytic activity.   It used to be a very common ingredient in the treatment of  [more]
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 viscosity controlling
irritancy, com. 0, 0
A highly absorbent clay that comes in different colors depending on its mineral content. It's excellent at absorbing things including sebum and gunk in the pores and it also has some skin soothing and "detoxifying" effect. [more]
what‑it‑does colorant | abrasive/scrub
irritancy, com. 0, 0
A type of clay that's a fine, white powder and is used for its oil-absorbing and opacifying properties. It's less absorbent and less drying than bentonite clay. [more]
what‑it‑does moisturizer/humectant | solvent | viscosity controlling
irritancy, com. 0, 0
A common glycol that improves the freeze-thaw stability of products. It's also a solvent, humectant and to some extent a penetration enhancer. [more]
what‑it‑does abrasive/scrub
irritancy, com. 0, 1
Talc is the major component of most powder makeup products (think face powder, eyeshadows, and blushers) that usually contain it up to 70%. Its two winning properties that make it very suitable for this role is its outstanding spreadability for a smooth application and its low covering power, aka translucency to avoid clown-like effects. [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 soothing | moisturizer/humectant
The famous aloe vera. A great moisturizer and anti-inflammatory ingredient that also helps wound healing and skin regeneration. [more]
what‑it‑does sunscreen
irritancy, com. 0, 1
A physical/inorganic sunscreen with the broadest spectrum (UVB and UVA II, less good at UVA I) protection available today. It also has good stability and also works as a skin protectant, anti-irritant. Might leave some whitish tint on the skin, though. [more]
what‑it‑does emulsifying | surfactant/cleansing
irritancy, com. 0, 0
It's a common little helper ingredient that helps water and oil to mix together. Also, it can help to increase the solubility of some other ingredients in the formula. 
what‑it‑does colorant
irritancy, com. 0, 0
Titanium dioxide as a colorant. It's a white pigment with great color consistency and dispersibility.
what‑it‑does viscosity controlling
irritancy, com. 0, 1
A handy white powder that magically converts a liquid into a nice gel formula. [more]
what‑it‑does perfuming
The generic term for nice smelling stuff put into cosmetic products so that the end product also smells nice. It is made up of 30 to 50 chemicals on average. [more]
what‑it‑does buffering
Lye - A solid white stuff that’s very alkaline and used in small amount to adjust the pH of the product.  [more]
what‑it‑does preservative
An antimicrobial preservative that helps your products not to go wrong too quickly. It works especially well against bacteria, specifically gram-negative species, yeast, and mold.Somewhat controversial, it belongs to an infamous family of formaldehyde-releasers. [more]
what‑it‑does preservative
irritancy, com. 0, 0
The most common type of feared-by-everyone-mostly-without-scientific-reason parabens. It's a cheap, effective and well-tolerated ingredient to make sure the cosmetic formula does not go wrong too soon.  Apart from the general controversy around parabens (we wrote about it more here), there is a 2006 in-vitro (made in the lab not on real people) research about methylparaben (MP) sho [more]
what‑it‑does preservative | perfuming
irritancy, com. 0, 0
A very common type of feared-by-everyone-mostly-without-scientific-reason parabens. It's a cheap, effective and well-tolerated ingredient to make sure the cosmetic formula does not go wrong too soon. [more]