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Skin science article

The INKEY List Polyhydroxy Acid (PHA) Toner Versus Niod Superoxide Dismutase Saccharide Mist

The INKEY List Polyhydroxy Acid (PHA) Toner Versus Niod Superoxide Dismutase Saccharide Mist This smoothing toner is formulated around Gluconolactone and Niacinamide to refine skin texture and brighten dull-looking skin. This calming toner is formulated around

The INKEY List Polyhydroxy Acid (PHA) Toner Versus Niod Superoxide Dismutase Saccharide Mist

This smoothing toner is formulated around Gluconolactone and Niacinamide to refine skin texture and brighten dull-looking skin.

This calming toner is formulated around Superoxide Dismutase to calm redness.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Propanediol

Gluconolactone 3%

Niacinamide 3%

Pentylene Glycol

Glycerin

Aloe Barbadensis Leaf Juice

Potassium Sorbate

Sodium Benzoate

PPG-26-Buteth-26

PEG-40 Hydrogenated Castor Oil

1,2-Hexanediol

Caprylyl Glycol

Ethylhexylglycerin

Citric Acid

Sodium Hydroxide

Water, Propanediol, Gluconolactone 3%, Niacinamide 3%, Pentylene Glycol, Glycerin, Aloe Barbadensis Leaf Juice, Potassium Sorbate, Sodium Benzoate, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, 1,2-Hexanediol, Caprylyl Glycol, Ethylhexylglycerin, Citric Acid, Sodium Hydroxide

Superoxide Dismutase

Malachite Extract

Pseudoalteromonas Exopolysaccharides

Mirabilis Jalapa Extract

Polypodium Vulgare Rhizome Extract

Cetraria Islandica Thallus Extract

Sphagnum Magellanicum Extract

Arginine

Butylene Glycol

Sodium Salicylate

Gellan Gum

Sodium Chloride

Tromethamine

Phenoxyethanol

Chlorphenesin

Water, Superoxide Dismutase, Malachite Extract, Pseudoalteromonas Exopolysaccharides, Mirabilis Jalapa Extract, Polypodium Vulgare Rhizome Extract, Cetraria Islandica Thallus Extract, Sphagnum Magellanicum Extract, Arginine, Propanediol, Glycerin, Pentylene Glycol, Butylene Glycol, Sodium Salicylate, Gellan Gum, Sodium Chloride, PPG-26-Buteth-26, PEG-40 Hydrogenated Castor Oil, Citric Acid, Tromethamine, Phenoxyethanol, Chlorphenesin

Reviews

Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Citric Acid is an alpha hydroxy acid (AHA) naturally found in citrus fruits like oranges, lemons, and limes.

Like other AHAs, citric acid can exfoliate skin by breaking down the bonds that hold dead skin cells together. This helps reveal smoother and brighter skin underneath.

However, this exfoliating effect only happens at high concentrations (20%) which can be hard to find in cosmetic products.

Due to this, citric acid is usually included in small amounts as a pH adjuster. This helps keep products slightly more acidic and compatible with skin's natural pH.

In skincare formulas, citric acid can:

While it can provide some skin benefits, research shows lactic acid and glycolic acid are generally more effective and less irritating exfoliants.

Most citric acid used in skincare today is made by fermenting sugars (usually from molasses). This synthetic version is identical to the natural citrus form but easier to stabilize and use in formulations.

Rosacea skin has a lower threshold for acids generally, with 62.5% of rosacea subjects in one study reacting to lactic acid in a sting test. This is why we mark citric acid as a potential rosacea trigger.

However, this ingredient shows up as a pH adjuster or chelator at roughly 0.1-1% in many products. These low levels are unlikely to be an issue for rosacea skin and becomes a potential trigger at exfoliating concentrations (20%). Because everybody's skin is unique, we recommend a patch test if you are unsure.

Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.

Topically, glycerin does several things at once:

Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.

Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.

This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.

Just know very high concentrations (>40%) can feel tacky in low humidity.

Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.

PEG-40 Hydrogenated Castor Oil is an emulsifier derived from castor oil.

As an emulsifying agent, it helps other ingredients like fragrances and fat-soluble vitamins dissolve cohesively.

Due to its large molecule size, it doesn't penetrate beyond the skin's surface.

This ingredient has a solid regulatory track record; the CIR Expert Panel first concluded it was safe for use in cosmetics at concentrations up to 100% in 1997. A 2012 reassessment reaffirmed that finding. Safety studies have also found no irritation or evidence of toxicity.

A 2019 study did find this ingredient to grow Malassezia, so this ingredient may not be fungal acne safe.

Pentylene Glycol (1,2-pentanediol) is a multitasking little diol with three main roles in a formula:

Research on alkanediols (the family pentylene glycol belongs to) show they work by disrupting microbial cell membranes. This disruption helps the primary preservative system in a product work more effectively at lower doses.

On the safety side, the Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe as used in current cosmetic practices + concentrations.

Typical use levels in a formula run about 1-5%.

We don't have a description for PPG-26-Buteth-26 yet.

Propanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.

It’s often used to:

Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!

Similar Comparisons

The reference edit

Ingredients, questions
& further reading.

Connected source records selected through this article’s public topic index.

01

Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Side-by-side

  1. 01Water
  2. 02Glycerin
  3. 03Dicaprylyl Carbonate
  4. 04Propanediol
  5. 05Polyglyceryl-6 Distearate
  6. 06Cetyl Alcohol
  7. 07Glyceryl Behenate
  8. 08Phenoxyethanol
  9. 09Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer
  10. 10Jojoba Esters
  11. 11Albizia Julibrissin Bark Extract
  12. 12Squalane
  13. 13Caffeine
  14. 14Polyglyceryl-3 Beeswax
  15. 15Phospholipids
  16. 16Ethylhexylglycerin
  17. 17Xanthan Gum
  18. 18Glycine Soja Oil
  19. 19Polysorbate 60
  20. 20Sodium Phytate
Source · skinsort.com
02

Product index

Related product references

Product

The Inkey List Niacinamide Serum

The Inkey List Niacinamide Serum The Inkey List Niacinamide Serum ingredients explained: Water (Aqua/Eau), Niacinamide (10%), Glycerin, Propanediol, Butylene Glycol, Phenoxyethanol, Hydroxy…

Source: incidecoder.comView reference →

Product

The Inkey List Lactic Acid Serum

The Inkey List Lactic Acid Serum The Inkey List Lactic Acid Serum ingredients explained: Aqua (Water), Lactic Acid, Propanediol, Glycerin, Sodium Hydroxide, PPG-26-Buteth-26, Sodium Hyaluro…

Source: incidecoder.comView reference →
03

Comparison edit

Read side by side