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Paula's Choice Skin Perfecting 25% AHA + 2% BHA Exfoliant Peel Versus Algenist Genius Liquid Skin Resurfacing 2% BHA Toner

Paula's Choice Skin Perfecting 25% AHA + 2% BHA Exfoliant Peel Versus Algenist Genius Liquid Skin Resurfacing 2% BHA Toner This smoothing exfoliator is formulated around Glycolic Acid and Lactic Acid to refine skin texture and brighten dull-looking skin. This

Paula's Choice Skin Perfecting 25% AHA + 2% BHA Exfoliant Peel Versus Algenist Genius Liquid Skin Resurfacing 2% BHA Toner

This smoothing exfoliator is formulated around Glycolic Acid and Lactic Acid to refine skin texture and brighten dull-looking skin.

This smoothing toner is formulated around Salicylic Acid and Niacinamide to refine skin texture and refine the look of pores.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Aminomethyl Propanol

Glycolic Acid

Lactic Acid

Mandelic Acid

Isoamyl Laurate

Tartaric Acid

Propanediol

Salicylic Acid

Malic Acid

Butylene Glycol

Clitoria Ternatea Flower Extract

Sodium Hyaluronate

Glycyrrhetinic Acid

Glycerin

Tocopherol

Bisabolol

Allantoin

Hydroxyethylcellulose

Hydrogenated Lecithin

Xanthan Gum

Polyglyceryl-4 Laurate

Polyacrylate Crosspolymer-6

Titanium Dioxide

Mica

Phenoxyethanol

Water, Aminomethyl Propanol, Glycolic Acid, Lactic Acid, Mandelic Acid, Isoamyl Laurate, Tartaric Acid, Propanediol, Salicylic Acid, Malic Acid, Butylene Glycol, Clitoria Ternatea Flower Extract, Sodium Hyaluronate, Glycyrrhetinic Acid, Glycerin, Tocopherol, Bisabolol, Allantoin, Hydroxyethylcellulose, Hydrogenated Lecithin, Xanthan Gum, Polyglyceryl-4 Laurate, Polyacrylate Crosspolymer-6, Titanium Dioxide, Mica, Phenoxyethanol

Niacinamide

Collagen Amino Acids

Parachlorella Beijerinckii Exopolysaccharides

Hydrolyzed Collagen

Azelaic Acid

Decyl Glucoside

Eucalyptus Globulus Leaf Extract

Lauryl Glucoside

Rosmarinus Officinalis Extract

Mentha Piperita Extract

Citrus Limon Fruit Extract

Dextrin

Amylopectin

Leuconostoc/Radish Root Ferment Filtrate

Ethylhexylglycerin

Sodium Hydroxide

Phytic Acid

Citric Acid

Sodium Benzoate

Potassium Sorbate

Water, Propanediol, Salicylic Acid, Niacinamide, Collagen Amino Acids, Parachlorella Beijerinckii Exopolysaccharides, Hydrolyzed Collagen, Azelaic Acid, Glycolic Acid, Decyl Glucoside, Eucalyptus Globulus Leaf Extract, Lauryl Glucoside, Rosmarinus Officinalis Extract, Mentha Piperita Extract, Citrus Limon Fruit Extract, Dextrin, Amylopectin, Leuconostoc/Radish Root Ferment Filtrate, Tocopherol, Ethylhexylglycerin, Sodium Hydroxide, Phytic Acid, Butylene Glycol, Citric Acid, Sodium Benzoate, Potassium Sorbate, Phenoxyethanol

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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.

Glycolic Acid is arguably the most famous alpha hydroxy acid (AHA) with tons of research backing its benefits.

It is found naturally in sugar cane but the form used in skincare is usually synthetic for purity and stability.

Glycolic acid removes the top layer of dead skin cells to allow newer and fresher ones to emerge.

AHAs work by breaking down the structural “glue” that holds old skin cells in place. When that buildup is gone, your skin can renew itself more efficiently.

Research also shows glycolic acid stimulates collagen production, helping to firm and thicken the skin over time. This is one of its biggest advantages over other AHAs.

Overall, glycolic acid helps with:

Fun fact: Glycolic acid boosts skin hydration by helping it produce molecules that increase hyaluronic acid naturally.

To work best, glycolic acid products should have a pH between 3-4 (that’s where exfoliation is most effective but still gentle on skin).

The pH and concentration of a product are key to its effectiveness:

It is normal to feel a slight stinging sensation when using glycolic acid. This usually fades as your skin adjusts.

Because glycolic acid has the smallest molecular size in the AHA family, it can penetrate deeper, which enhances its effectiveness but also makes it more likely to irritate sensitive skin.

If your skin is very sensitive or prone to rosacea, glycolic acid may be too strong; in that case, try milder options like lactic acid or a PHA instead.

Recent studies suggest glycolic acid might even help protect against UV damage. But don’t skip sunscreen! Freshly exfoliated skin is more sensitive to the sun.

Glycolic acid is a skincare superstar. It smooths, brightens, hydrates, and firms the skin. Unless you’re highly sensitive, it’s well worth adding to your routine.

Read more about some other popular AHA's here:

Phenoxyethanol is one of the most widely used preservatives in skincare (and for good reason!).

It has a large spectrum of antimicrobial activity and especially effective bacteria, yeast, and mold while only having a weak effect on your skin's natural microbiome.

On a cellular level, it disrupts the cell membranes of microbes by poking holes that make the cell leak. This shuts down the chemical reactions the microbe needs to make energy so it can no longer survive.

Another perk of this ingredient is that it stays functional across a wide pH range (3-10).

You'll often see it paired with boosters like Ethylhexylglycerin; one study showed that a 1:9 ratio of Ethylhexylglycerin to Phenoxyethanol damages bacterial membranes as effectively as doubling the Phenoxyethanol concentration on its own.

Typical use concentrations range from 0.3-1% depending on the formula, and this ingredient is capped at 1% int the EU.

Safety-wise, the fear mongering does not hold up to the evidence. The EU's Scientific Committee on Consumer Safety and FDA consider it safe as a preservative at up to 1%, including for children of all ages.

Adverse systemic effects only showed up in animal studies at exposures roughly 200x higher than what people get from cosmetics. And despite its very widespread use, this ingredient is a rare sensitizer and allergic reactions are uncommon.

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.

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.

Tocopherol is a fat-soluble antioxidant known as Vitamin E.

You'll find this ingredient in the vast majority of skincare (for good reason). It works to neutralize free radicals, or unstable molecules generated by UV exposure, pollution, and other environmental stressors, before they can cause oxidative damage to your skin cells.

Topically applied tocopherol has been shown to protect against UV damage by ramping up the skin's own natural defense enzymes.

It also acts as a skin conditioning agent; some studies show that regular topical use can improve the skin's water-binding capacity over 2-4 weeks.

This ingredient is especially loved for being a team player. When combined with Vitamin C, the photoprotective effect of both ingredients roughly doubles and the combo also helps reduce UV-induced DNA damage.

This ingredient has some brightening potential but it's more of a prevention ingredient than spot-fader. Cell studies show it can slow down melanin production but it's worth noting that it's not the most powerful brightener out there.

In formulations, it also serves as a stabilizer that helps protect other oxidation-prone ingredients from degrading.

Concentrations usually range from 0.1-1% in most leave-on products.

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. 02Aminomethyl Propanol
  3. 03Glycolic Acid
  4. 04Lactic Acid
  5. 05Mandelic Acid
  6. 06Isoamyl Laurate
  7. 07Tartaric Acid
  8. 08Propanediol
  9. 09Salicylic Acid
  10. 10Malic Acid
  11. 11Butylene Glycol
  12. 12Clitoria Ternatea Flower Extract
  13. 13Sodium Hyaluronate
  14. 14Glycyrrhetinic Acid
  15. 15Glycerin
  16. 16Tocopherol
  17. 17Bisabolol
  18. 18Allantoin
  19. 19Hydroxyethylcellulose
  20. 20Hydrogenated Lecithin
Source · skinsort.com
02

Product index

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03

Comparison edit

Read side by side