Peptide Skincare & BeautySkin science and ingredient guides

Skin science article

Paula's Choice Skin Perfecting 2% BHA Gel Exfoliant Versus Paula's Choice Clear Extra Strength Anti-Redness Exfoliating Solution

Paula's Choice Skin Perfecting 2% BHA Gel Exfoliant Versus Paula's Choice Clear Extra Strength Anti-Redness Exfoliating Solution This pore-care exfoliator is formulated around Salicylic Acid and Phytosphingosine to refine the look of pores and refine skin text

Paula's Choice Skin Perfecting 2% BHA Gel Exfoliant Versus Paula's Choice Clear Extra Strength Anti-Redness Exfoliating Solution

This pore-care exfoliator is formulated around Salicylic Acid and Phytosphingosine to refine the look of pores and refine skin texture.

This acne exfoliator is formulated around Salicylic Acid to clear breakouts and refine the look of pores.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Methylpropanediol

Butylene Glycol

Polysorbate 20

Salicylic Acid

Phytosphingosine

Hydroxyethylcellulose

Vitis Vinifera Seed Extract

Camellia Oleifera Leaf Extract

Epilobium Angustifolium Extract

Bisabolol

Tetrasodium EDTA

Sodium Hydroxide

Water, Methylpropanediol, Butylene Glycol, Polysorbate 20, Salicylic Acid, Phytosphingosine, Hydroxyethylcellulose, Vitis Vinifera Seed Extract, Camellia Oleifera Leaf Extract, Epilobium Angustifolium Extract, Bisabolol, Tetrasodium EDTA, Sodium Hydroxide

Salicylic Acid 2%

Phenoxyethanol

Salicylic Acid 2%, Water, Methylpropanediol, Butylene Glycol, Polysorbate 20, Camellia Oleifera Leaf Extract, Sodium Hydroxide, Tetrasodium EDTA, Phenoxyethanol

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.

Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:

Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.

Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.

Camellia Oleifera Leaf Extract comes from the leaves of the tea oil plant, the cousin of the green tea plant Camellia Sinensis. This ingredient is mainly added to skincare as a mild skin-conditioning and astringent ingredient.

Early lab studies show it can calm inflammation and slightly inhibit the enzyme that triggers dark spots. Modern studies also show it to have antibacterial and antioxidant effects that support anti-inflammatory use.

There's no dedicated safety review for this ingredient for now, but its cousin Camellia Sinensis has been reviewed and found to be without safety concerns.

Like most botanical extracts, this ingredient carries a low but real chance of contact allergy or mild irritation in sensitive individuals.

Methylpropanediol is a synthetic solvent and humectant.

As a solvent, it helps dissolve other ingredients, helping to evenly distribute ingredients throughout the product. This ingredient has also been shown to have antimicrobial properties which makes it a preservative booster.

Methylpropanediol is able to add a bit of moisture to the skin. It also helps other ingredients be better absorbed into the skin, such as salicylic acid.

Polysorbate 20 is a gentle, water-soluble emulsifier and mild surfactant. It stops oil and water from separating to keep your formulas blended and stable.

It also acts as a mild penetration enhancer by helping active ingredients absorb slightly better.

The common safety discussion around this ingredient involves a manufacturing byproduct called 1,4-dioxane.

Trace amounts can form during production but the EU's Scientific Committee on Consumer Safety has concluded that levels at/below 10 ppm in finished products are safe (commercial products consistently fall within acceptable margins).

True allergic reactions are uncommon and the CIR Expert Panel has confirmed this ingredient to be safe as used in cosmetics.

Because it is derived from lauric acid, it may not be fungal acne safe.

Salicylic Acid (also known as beta hydroxy acid or BHA) is a well-known ingredient for treating skin that struggles with acne and clogged pores. It exfoliates both the skin's surface and deep within the pores to help clear out buildup, control oil, and reduce inflammation.

Unlike AHAs (alpha hydroxy acids), salicylic acid is oil-soluble. This allows it to penetrate into pores which makes it especially effective for treating blackheads and preventing future breakouts.

Salicylic acid is also known for its soothing properties. It has a similar structure to aspirin and can calm inflamed or irritated skin, making it a good option for acne-prone skin that is also sensitive.

Concentrations of 0.5-2% are recognized by the U.S. FDA as an over-the-counter topical acne product.

It can cause irritation and/or dryness if one's skin already has a compromised moisture barrier, so it's best to focus on repairing that before introducing this ingredient into your routine.

While salicylic acid does not increase sun sensitivity, it’s still important to wear sunscreen daily to protect your skin.

If you are looking for the ingredient called BHA or Butylated Hydroxyanisole, click here.

Sodium Hydroxide is also known as lye or caustic soda. It is used to adjust the pH of products; many ingredients require a specific pH to be effective.

In small amounts, sodium hydroxide is considered safe to use. However, large amounts may cause chemical burns due to its high alkaline.

Your skin has a natural pH and acid mantle. This acid mantle helps prevent harmful bacteria from breaking through. The acid mantle also helps keep your skin hydrated.

"Alkaline" refers to a high pH level. A low pH level would be considered acidic.

Tetrasodium EDTA is the salt formed from neutralizing ethylenediamine tetraacetic acid with sodium hydroxide. It is a chelating agent and used to prevent metal ions from binding to other ingredients. This helps keep the product and ingredients stable.

Tetrasodium EDTA comes as a white solid and is soluble in water.

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 Explained

  1. 01These ingredients are found in both products.
  2. 02Ingredients higher up in an ingredient list are typically present in a larger amount.
  3. 03Butylene Glycol (or BG) is used within cosmetic products for a few different reasons:
  4. 04Overall, Butylene Glycol is a safe and well-rounded ingredient that works well with other ingredients.
  5. 05Though this ingredient works well with most skin types, some people with sensitive skin may experience a reaction such as allergic rashes, closed comedones, or itchiness.
  6. 06Ethylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
  7. 07The CIR Expert Panel found minimal skin absorption or sensitization of any kind in a safety assessment. Though this ingredient is considered well-tolerated, a small number of cases of allergic dermatitis have been published since 2002. Just be sure …
  8. 08Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
  9. 09Glycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
  10. 10Topically, glycerin does several things at once:
  11. 11Your 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.
  12. 12Aquaporin-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.
  13. 13This 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.
  14. 14Just know very high concentrations (>40%) can feel tacky in low humidity.
  15. 15Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
  16. 16Niacinamide is a multitasking form of vitamin B3 that strengthens the skin barrier, reduces pores and dark spots, regulates oil, and improves signs of aging.
  17. 17And the best part? It's gentle and well-tolerated by most skin types, including sensitive and reactive skin.
  18. 18You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.
  19. 19In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.
  20. 20If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.
Source · skinsort.com
02

Product index

Related product references

03

Comparison edit

Read side by side