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Obagi Blue Brilliance Triple Acid Peel Versus Obagi Professional-C Serum 20%

Obagi Blue Brilliance Triple Acid Peel Versus Obagi Professional-C Serum 20% This smoothing treatment is formulated around Salicylic Acid and Lactic Acid to refine skin texture and brighten dull-looking skin. This brightening serum is formulated around Ascorbi

Obagi Blue Brilliance Triple Acid Peel Versus Obagi Professional-C Serum 20%

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

This brightening serum is formulated around Ascorbic Acid and Ascorbyl Glucoside to brighten dull-looking skin and soften the look of wrinkles.

What's inside

Key Ingredients

Benefits

Concerns

Ingredients Side-by-side

Sd Alcohol 40-B

Water

Salicylic Acid

Ethoxydiglycol

Lactic Acid

Glycolic Acid

Propylene Glycol

Butylene Glycol

Glycerin

Glycyrrhiza Glabra Root Extract

Phenoxyethanol

Salix Alba Bark Extract

Hamamelis Virginiana Extract

CI 17200

CI 42090

Sd Alcohol 40-B, Water, Salicylic Acid, Ethoxydiglycol, Lactic Acid, Glycolic Acid, Propylene Glycol, Butylene Glycol, Glycerin, Glycyrrhiza Glabra Root Extract, Phenoxyethanol, Salix Alba Bark Extract, Hamamelis Virginiana Extract, CI 17200, CI 42090

Ascorbic Acid

Alcohol

Ascorbyl Glucoside

Sorbitol

Sodium Hyaluronate

Zinc Chloride

Calcium Hydroxide

Parfum

Propylene Glycol, Water, Ascorbic Acid, Alcohol, Ascorbyl Glucoside, Ethoxydiglycol, Phenoxyethanol, Sorbitol, Sodium Hyaluronate, Zinc Chloride, Calcium Hydroxide, Parfum

Alternatives

Ingredients Explained

These ingredients are found in both products.

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

Ethoxydiglycol (aka Diethylene Glycol Monoethyl Ether) is one of the cosmetic world's quiet problem solvers.

In a formula, it is a solvent that dissolves tricky ingredients that don't want to mix in and helps spread ingredients evenly across your skin without leaving a greasy or sticky feeling

This makes it great for hard-to-dissolve actives like vitamin C, benzoyl peroxide, and self-tanner DHA.

It also has mild humectant and penetration enhancer abilities so it can help some actives absorb a little deeper.

The penetration boost is backed by lab research: studies using human skin samples found it improved how well an active dissolves into the upper layer of skin rather than tearing down your skin barrier. Reviews of its mechanism also describe it interacting gently with the lipids and water in your outermost layer of skin.

Just know this penetration-enhancing effect is not universal. It helps a lot in some formulas and did very little in others (so the benefit really depends on the specific product).

Safety-wise, the evidence is reassuring. The Cosmetic Ingredient Review Expert Panel reviewed it and concluded it's safe for use in cosmetics and recognized it as non-irritating, non-sensitizing, and non-comedogenic in skincare.

Typical leave-on skincare usage lands around 1-10%. The EU has sets caps of 2.6% in non-spray products, 10% in rinse-offs, 7% in oxidative hair dye, and 5% in non-oxidative hair dye.

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.

Propylene Glycol is a synthetic, colorless, odorless liquid that has been a staple in cosmetics for decades. It is a skin conditioning agent, humectant, and solvent.

As a humectant, it draw water to the skin to reduce flaking and restore suppleness. It's also a solvent that helps dissolve other actives and keeps formulas stable across temperature changes.

The CIR Expert Panel has confirmed this ingredient to be nontoxic and clinical studies show no sensitization at cosmetic use concentrations.

True allergic reactions are quite rare: a 15-year retrospective study of 6,751 patients found only 0.31% had a positive reaction (and less than half were considered clinically relevant).

It seemed that when sensitization does occur, it's most commonly linked to topical medication (like corticosteroids) and not cosmetics. Allergic contact dermatitis also appears largely limited to individuals with underlying skin conditions.

Overall, propylene glycol is a well-studied ingredient that most people can tolerate without issue.

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. 01Butyl Methoxydibenzoylmethane 3%
  2. 02Homosalate 8%
  3. 03Ethylhexyl Salicylate 5%
  4. 04Octocrylene 2.79%
  5. 05Benzophenone-3 3%
  6. 06Ascorbic Acid
  7. 07Citrus Grandis Peel Extract
  8. 08Dimethicone
  9. 09Dimethicone Crosspolymer
  10. 10Parfum
  11. 11Octoxynol-10
  12. 12Butyl Methoxydibenzoylmethane 3%, Homosalate 8%, Ethylhexyl Salicylate 5%, Octocrylene 2.79%, Benzophenone-3 3%, Ascorbic Acid, Citrus Grandis Peel Extract, Dimethicone, Dimethicone Crosspolymer, Parfum, Octoxynol-10
  13. 13Propylene Glycol
  14. 14Water
  15. 15Alcohol
  16. 16Ascorbyl Glucoside
  17. 17Ethoxydiglycol
  18. 18Phenoxyethanol
  19. 19Sorbitol
  20. 20Sodium Hyaluronate
Source · skinsort.com
02

Product index

Related product references

Product

Obagi Professional-C Serum 20%

Obagi Professional-C Serum 20% Ingredients in Obagi Professional-C Serum 20% explained: benefits, concerns, and detailed analysis of 12 ingredients including Propylene Glycol, Water, and As…

Source: skinsort.comView reference →
03

Comparison edit

Read side by side