At a Glance
Avobenzone is a very common UVA filter in sunscreens, yet its stability, safety, and environmental concerns continue to be a matter of discussion. Formulators need to have a delicate balance between efficacy, photostability, and regulation to achieve best-in-class sun protection. In this article, avobenzone is reviewed in comparison to other UV filters, which aids formulators in making an educated choice.
Introduction
As a cosmetic formulator or skin care enthusiast, you might have questioned, “Is avobenzone safe?” Avobenzone is an in-demand sunscreen ingredient with the reputation for delivering UVA protection. But one often hears reservations regarding its stability, possible toxicity, and even environmental effect. Moreover, some question, “What is avobenzone, and is avobenzone reef safe?”
This paper presents a rigorous scientific analysis of the safety of avobenzone in relation to other UV filters to assist formulators in making informed choices.
What is Avobenzone?
Avobenzone (Butyl Methoxydibenzoylmethane) is an organic UVA filter that is absorbed by UVA rays (320–400 nm). Discovered in the 1980s, it is still among the few UVA filters that have been FDA-approved. Avobenzone is usually used with photostabilizers such as octocrylene in order to enhance its performance because it degrades upon exposure to the sun.
How Avobenzone Works
Avobenzone functions by absorbing UVA radiation and dissipating it in less damaging forms, e.g., heat, to avoid skin damage. It is unstable by nature and can break down under sun exposure, losing its effectiveness with time. To make it more stable, it is blended with stabilizers such as octocrylene or formulated in sophisticated sunscreen products. This guarantees longer protection from photoaging and skin damage due to UVA.
Avobenzone is one of the active ingredients of chemical sunscreens, recognized for its powerful protection against UVA. In conjunction with UVB filters, it contributes to developing a broad-spectrum product that protects the skin from aging as well as burning rays. Reapplication of sunscreen frequently to provide ongoing protection, particularly when outdoors for an extended period, is necessary.
Is Avobenzone Safe? A Scientific Evaluation
Avobenzone is a chemical sunscreen ingredient extensively used for broad-spectrum protection against UVA rays. It is approved in many countries but the discourse on safety has a strong bias towards skin irritancy, endocrine disruption, and photostability. Below is a detailed safety assessment of avobenzone through scientific research.
Skin Safety & Toxicity
Low Acute Toxicity: Avobenzone is well-accepted as being safe for the topical application of not more than 3% concentration in the U.S. and 5% in the EU. According to studies, avobenzone is considered to be of low acute toxicity meaning it does not generally cause significant irritation, allergic reactions, or a sensitization response in the majority of the individuals. However, the few with sensitive skin may experience slight irritation or contact dermatitis.
Endocrine Disruption Concerns: There have been concerns that avobenzone and other chemical UV filters are suspected of endocrine disruption. Some laboratory studies have reported some level of weak hormone activity for avobenzone. However, the evidence remains inconclusive. Another problem is that concentrations used in such studies are often higher than real-life exposure levels, and there is no obvious reason why the U.S. FDA or the European Commission would label avobenzone an endocrine disruptor of concern.
Photodegradation & Free Radical Formation: A significant issue arising with avobenzone is its instability. Avobenzone breaks down under UV radiation with time, forming degradation products which can generate free radicals. Free radicals can induce oxidative stress, leading to skin that exhibits signs of aging well before its time and cellular damage.
Regulations dictate that the effective use of sunscreen involves stabilizers, including:
- Octocrylene—Helps in increasing the stability of avobenzone in sunlight.
- Tinosorb S and Tinosorb M—Advanced UV filters that impart stability.
- Antioxidants (e.g., Vitamin E & C)—Neutralize free radicals and reduce oxidative stress.
Thus, a good formulation of sunscreens minimizes degradation of avobenzone making them effective and safe.
Is Avobenzone Reef Safe?
Whether avobenzone is reef-safe is a question of great importance for environment-friendly formulators and consumers searching for eco-safe sunscreens. Not being as badly criticized as oxybenzone and octinoxate, theoretical research does however show that it may pose some risk to the marine ecosystem. Some enterprising studies demonstrated that avobenzone could be degraded in seawater, to form several toxic byproducts which may damage coral reefs and marine life.
The increasing discussion around its environmental safety has lately redirected a lot of research interest into alternative sunblock materials that hopefully have a much lower impact on the environment.
Also Read: Sustainable Practices In The Personal Care Industry
How Does Avobenzone Affect Marine Life?
- Photodegradation Products: When avobenzone meets the seawater in the presence of sunlight, it has the potential to degrade into harmful organic compounds that affect the marine ecosystems themselves. These degradation products tend to have oxidizing factors which have been related to coral damage in terms of inhibiting survival and reproduction. Moreover, prolonged exposure to such factors will lead to processes like coral bleaching and the decline of biodiversity on reefs.
- Bioaccumulation Risk: Avobenzone present does not linger for long as other ultraviolet chemical filters, but traces of residues still tucked away in water bodies. These residues may actually interfere with biological processes such as growth, reproduction, and cellular function in regarding fish, invertebrates, and coral. Exposure to avobenzone is still considered an area of ongoing research to study long-term effects in marine organisms, but preliminary results indicate that benefits may accrue to sensitive ecosystems if its concentration could be reduced in ocean waters.
- Alternative Reef-Safe Filters: For anyone in the quest for sustainable sunshine protection, mineral-based UV filters, zinc oxide, and non-nano titanium dioxide are the most reef-safe options available. These ingredients cause broad-spectrum protection from UV rays, not breaking down to any harmful compounds in seawater. Many reef-safe sunscreen brands offer these alternatives in their formulations to protect marine biodiversity and provide the consumers with good protection against the sun.
Stability and Formulation Challenges
Photostability Issues: Avobenzone has one of the major drawbacks of sunlight instability. Within 30 minutes of exposure to UV light, degradation began, which decreased its ability to be used as a UVA filter.
Mechanism of Degradation
- Photodecomposition: UV irradiation brings about the photodecomposition of avobenzone into by-products, which can diminish protection against UVA and generate free radicals.
- Keto-Enol Tautomerism: Avobenzone occurs in two interconverting forms, namely keto and enol. The enol exists predominantly in sunscreen formulations due to better UVA absorption than the other. Light exposure precipitates chemical changes that effectively degrade this protective function.
Ideal Sunscreen Formulation Strategies
Combining with Stabilizers
- Octocrylene: One of the most common stabilizers shielding UV radiation and preventing avobenzone degradation.
- Diethylhexyl Syringylidene Malonate (Oxynex ST): It is an antioxidant and stabilizer with UV photostabilization and antioxidant efficiency.
- Bemotrizinol (Tinosorb S): A definite broad-spectrum photostable UV filter adding in further protection and preventing avobenzone degradation.
Encapsulation Technology
Some cosmetic houses will microencapsulated avobenzone to protect it from light and oxygen. Such an approach:
- Protects against photodegradation by encapsulating avobenzone in an outer protective shell.
- Decreases irritation to the skin by controlling pilot release of active ingredients.
- Increases stability of the sunscreen, providing much longer daytime protection utilization.
Layering with Physical Filters
- Zinc Oxide & Titanium Dioxide: They are broad-spectrum mineral filters that provide natural photoprotective properties and help stabilize avobenzone as they reflect UV rays before they can degrade the chemical filter.
- Hybrid Sunscreens: Modern formulations are avobenzone mixed with mineral filters for a more stability effect with even fewer free radical formations.
Use of Antioxidants
- Vitamin E (Tocopherol) & Vitamin C (Ascorbic Acid) – These antioxidants help deal with radical substances formed during the degradation of avobenzone.
- Polyphenols (e.g., Green Tea Extract, Resveratrol) – Natural antioxidants which further defend the skin against oxidative destruction.
Regulatory Considerations
The diverse regional usage and approval of avobenzone result from differences in regulatory policies regarding scientific evaluations and the availability of other UV filters. Although avobenzone is still the most widely used UVA filter worldwide, some regions have restrictions on its use or prefer newer, more stable sunscreen ingredients.
- United States (U.S.): Avobenzone is approved by the FDA for use in sunscreens up to a concentration of 3% but because the ingredient has undergone photodegradation, such formulations have to be stabilized with octocrylene. Adding more stiffer regulations, the FDA does not open a window for newer, more photostable UV filters like Tinosorb S and M.
- European Union (EU): The EU approved avobenzone at up to 5% concentration, which will provide stronger UVA protection, but European sunscreens have preferred newer and more stable filters such as Tinosorb S and M. The specification for UVA protection is still that it must be at least one-third of SPF to ensure that the formulation is really broad spectrum.
- Australia and Canada: Avobenzone is accepted in Australia and Canada with a high emphasis on stability and SPF, mainly due to high UV exposure. Sunscreens often contain Tinosorb S and some antioxidants and stabilizers to photostabilizer and make the sunscreen more durable.
Also Read: The Crucial Role Of Ethyl Acetate In The Cosmetic Market
How Should Formulators Approach Avobenzone?
- Pairing with Photostabilizers: To keep avobenzone from popping into its inactive form or degrading upon exposure to sunlight, formulating it with one or more stabilizers, including octocrylene, diethylhexyl syringylidene malonate, or Tinosorb S, would be desired. Finally, such a formulation would be subjected to relevant tests for photostability to ensure that the ability is maintained.
- Alternative UV Filters: For protection beyond that which may be achieved with organic photoprotectants, formulators may include such mineral filters as zinc oxide and titanium dioxide that are optimal for reef safe formulations. Tinosorb S & M, in addition, provides both wavelength portions with high stability characteristics, thus being a good substitute.
- Consumer Education: Consumer education about sunscreen application, reapplication, and the advantages of using reef-friendly formulations is mandatory. The clearer the guidelines are, the better the consumer’s chances of maximizing UV protection and simultaneously minimizing potential risks to a person’s skin health and the environmental well-being.
Also Read: Which Chemical Material Sourcing Strategy is Best for Your Chemical Business?
Conclusion
So to answer the question “is Avobenzone safe?” Well, yes it is an excellent UVA filter with high safety on the skin but low photostability and risk for environmental exposure. Thus, proper stabilization is a must, or else formulators may resort to alternatives such as Tinosorb and mineral filters. In prioritizing the reef’s safety, the most reasonable option would be zinc oxide-formulated products.
Elchemy is the best one-stop source for all innovation-driven, proven-safe, and sustainable sunscreen formulations. We deliver innovations that maximize the UV protection of a sunscreen formulation. Yet, they comply with global regulatory requirements and are well suited for ecologically responsible integration into formulations. Access Elchemy.com today to improve your formulation.
