Some beauty brands avoid using hexylresorcinol in their skin care products due to a misconception that it is closely related to — and just as harmful as — resorcinol. In this blog post, we set the record straight about the difference between hexylresorcinol and resorcinol.
Brands aspiring to qualify for the “Clean” seal of approval from popular beauty retail companies like Clean At Sephora and Conscious Beauty at Ulta sometimes think twice before incorporating hexylresorcinol into their skin care line. Unfortunately, there is a misconception that hexylresorcinol is unsafe because it contains the term “resorcinol” in its name, and the presence of resorcinol could hinder a product’s eligibility for these Clean standards.
However, hexylresorcinol does not pose the same dangers as resorcinol. Its similarities to resorcinol begin and end in the name. To understand the differences, let’s define both.
What Is Hexylresorcinol?
Hexylresorcinol is an organic compound that is classified as an alkylresorcinol, which is naturally present in the human body and bran fractions of rye and other cereals. Produced by organic synthesis, hexylresorcinol has GRAS status (Generally Recognized as Safe) and has a remarkable, almost 100-year history in food and pharmaceuticals. For example, it is used to prevent melanosis in shrimp and provide antiseptic and anesthetic properties to throat lozenges.
Hexylresorcinol has also been used in skin care for over 15 years as a skin lightener and even toner under the trade name Synovea® HR. Synovea® HR brightens the skin’s complexion, provides effective melanin inhibitory activity, and shows a significant improvement in skin clarity, complexion, and hydration.
With Sytheon’s efforts of over 15 years, HR has been established to be safe and effective topically. It is currently being used globally, including China. Over 100 brands across the world — from pharma companies and luxury goods to mass market brands — trust Synovea® HR as the gold standard for developing skin brightening and even toning products.
It was confirmed by HRIPT (5% HR in corn oil) to show no signs of irritation or sensitization, making HR a safe topical ingredient at the recommended use level of 0.5 to 1%.
With a purity level of almost 100%, Synovea® HR is essentially free of resorcinol and its intermediate hexanoylresorcinol.
What Is Resorcinol?
Resorcinol is a synthetic compound that lacks hexyl functionality. Produced through a complex synthetic process, resorcinol was originally invented in the 1800s for use as an antiseptic, representing a significant discovery of its time. It has been widely used in hair dyes and acne medications.
However, resorcinol is known today as a skin irritant, and its lack of alkyl functionality makes it corrosive. It is prohibited for use in products that wish to meet Clean criteria, including Clean At Sephora and Conscious Beauty at Ulta Beauty™.
Brands that wish to meet Clean criteria are worried about formulating with hexylresorcinol and being flagged for resorcinol. Here are three things you should know about hexylresorcinol vs. resorcinol.
Hexylresorcinol vs. Resorcinol: 3 Important Differences
Hexylresorcinol Has a Different Chemical Structure
Hexylresorcinol has a different chemical structure from resorcinol. It also has a different chemical composition, as represented by the different molecular formulas:
- Hexylresorcinol: C12H18O2
- Resorcinol: C6H4(OH)2
With a different chemical composition and structure, hexylresorcinol exhibits different properties from resorcinol. Meanwhile, the well-known chemical Resveratrol belongs to the stilbenes group and possesses two aromatic rings, one of which has resorcinol functionality. When 0.5 to 1.0% is used in a skin care formula, hexylresorcinol provides skin brightening and even toning benefits.
Hexylresorcinol Is Essentially Free of Resorcinol
Despite having it in the name, hexylresorcinol is essentially free of resorcinol, especially highly pure HR (Synovea® HR). The purer the HR, the less room there is for trace compounds.
Hexylresorcinol Is Safe
Hexylresorcinol (Synovea® HR) is considered one of the most safe and high performing skin lightening ingredients in the industry. With GRAS status, it is safe to use on the skin and is non-toxic and non-carcinogenic.
Synovea® HR has been rigorously tested to prove clinical efficacy and safety. In fact, 1% Synovea® HR has been found to match the effectiveness of 2% hydroquinone, without the safety concerns of hydroquinone.
As demonstrated, hexylresorcinol is different from resorcinol. Truly, the only common ground is the fact that hexylresorcinol has the word “resorcinol” in it.
Hexylresorcinol vs. Resorcinol: Final Thoughts
When looking for an active ingredient for your skin care product, it is important to find one that is safe and high performing. The only way to know this is by looking at an ingredient’s safety and clinical studies and ensuring that you are using the purest form of that ingredient.
Large multinational companies have been using Sytheon grade material for well over 12 years. Synovea® HR is globally approved, REACH registered, and patented. Multiple clinical studies with Synovea® HR demonstrated its strong performance in skin brightening and hyperpigmentation control for all skin types. Using Synovea® HR in your formula will not disqualify your product from Clean standards.