What Is Octinoxate?
Octinoxate is used in sunscreen formulations as a chemical UV absorber. Octinoxate is mainly valued for its ability to absorb UV rays, which produce free radicals, damage healthy skin cells and increase the rate of aging. By now you probably know the benefits of using a daily sunscreen; octinoxate is a common ingredient in many sunscreen formulations.
Octinoxate or octyl methoxycinnamate is a clear non-water-soluble liquid. It is often used in combination with other chemical sunscreens to help improve its protective abilities against the sun’s harmful rays.
There is much controversy over the safety of this ingredient for regular use and its impact on the environment, in particular reefs. While Octinoxate is approved and considered safe for its indicated uses in topical sunscreens the rumours around the safety of this ingredient still circulate. We will delve into the concerns around safety below.
the good: Protects the skin from the damage associated with UV rays, helps to prevent the visible signs of aging, and limits the production of free radicals.
the not so good: Potentially harmful to the health of reefs and may have impacts on human health with long-term use.
Who is it for? All skin types except those that have an identified allergy to it.
Synergetic ingredients: Works well with most ingredients.
Keep an eye on: The concentration of octinoxate in the product. Most countries regulate the concentration of octinoxate in the formulation.
How Does Octinoxate Work?
Octinoxate is made by combining sulfuric acid with methanol. It is a chemical sunscreen agent that works to filter out UVB rays from the sun. There are two types of UV rays, UVA and UVB. Different chemical sunscreen will work to protect your skin from one of these types of UV rays. This is why Octinoxate is often combined with other sunscreen ingredients such as avobenzone. Avobenzone protects your skin against UVA rays.
Sunscreens protect your skin from the damage caused by UV rays. This includes burning, premature signs of ageing and free radical damage. As such, octinoxate protects the skin from the production of free radicals.
Free radicals are produced from a process called oxidative stress. Oxidative stress produces an imbalance in the levels of free radicals in the body, causing damage to the body’s tissues and cells. Free radicals, also called reactive oxygen species or ROS, are a natural by-product of the body’s chemical processes. Think of them as your body’s waste.
Free radicals can accumulate and create an imbalance. This imbalance has been studied for its links with many diseases and its role in the aging process such as the appearance of deep wrinkles, pigmentation, and loss of elasticity. Antioxidants such as vitamin E or C are used in conjunction with chemical sunscreens to improve their ability to protect the skin against free radical damage. Make sure to look for a sunscreen formulation with vitamin E or C included in it. Chemical sunscreens, like those that include octinoxate in their formulation, help to protect the skin from sunburn, aging, and skin cancer.
Chemical Sunscreen vs. Physical Sunscreen
There are two categories of sunscreens on the market, one is physical, and one is chemical. Octinoxate falls into the chemical-based sunscreen category. However, it is essential to understand the difference when determining which product is for you.
Physical sunscreens work by absorbing the UV rays from the sun and transferring it into heat. Physical sunscreens are often described as working by relfecting the UV rays from the skin. This isn’t technically true, while physical sunscreens do reflect UV rays, they only reflect about 10% of the rays. The rest of the UV rays are absorbed and converted into heat, exactly like chemical sunscreens. The heat that is produced from this action is negligible and doesn’t damage the skin.
These types of formulations rely on the use of ingredients such as zinc oxide and titanium dioxide to provide this protection. Physical sunscreens create a barrier between the skin and the sun and aren’t absorbed into the skin. They are generally broad-spectrum, meaning that they protect against both UVA and UVB rays.
As physical sunscreens are designed to sit on top of the skin, they will often leave a whitecast on the skin when used correctly.
Chemical sunscreens are absorbed into the skin and absorb the sun’s harmful rays before they can penetrate deep enough to cause damage to the skin. Often chemical sunscreens are used in combination with another chemical sunscreen to provide broad-spectrum protection.
In the case of octinoxate, it is commonly used in conjunction with UVA blocking ingredients as octinoxate works best in preventing UVB. While octinoxate protects against UVA, it doesn’t protect as well as it does against UVB so it is used in combination with another chemical sunscreen.
Also, both types of sunscreens, physical and chemical, will often include ingredients such as vitamin C or E to protect against damage from free radicals. Free radical damage is more likely to occur with chemical sunscreens than with physical sunscreens, so these ingredients are important to look for in your sunscreen product.
Is Octinoxate Actually Safe?
Generally, octinoxate is considered to be safe for its indicated use in sunscreens. There is a large body of research that suggests that the ingredient is safe and decades of usage that suggests that it isn’t harmful to the body. The main studies that are cited when looking at its safety are studies that use high concentrations of the ingredients, concentrations that are outside of the scope of topical sunscreen use.
These studies are undertaken to determine safety but test extreme conditions and high concentrations. There is little evidence to suggest that there is any harm caused when used in the concentrations used in sunscreen formulations. In the US, under the FDA concentrations of octinoxate are limited to 7.5% and in the EU, under the CosIng regulations, it is limited to 10%.
There has been a significant amount of research into this ingredient, especially since the controversy around its use has increased in recent years. However, Healthline argued there have been few long-term studies conducted in humans. Most human studies have only recorded issues with irritation and allergies.
One concern that has been studied is its impact on the environment. In 2018, Hawaii passed a bill to ban sunscreens containing octinoxate due to the bleaching effect it may have on coral reefs. According to a few studies, some chemical sunscreen may be contributing to the decline in the health of coral reefs around the world.
However, what is important to note is that coral bleaching caused by sunscreen ingredients, including natural or reef friendly alternatives like zinc oxide are considered a low level contributing factor.
Reproductive health concerns
Research has presented some evidence that octinoxate can produce reproductive problems. These reproductive problems include reduced sperm count and endocrine or hormone disruption. Most of this research has been produced in animal studies and hasn’t been reproduced in humans. Again, these studies used high concentrations of octinoxate and are outside the scope of topical use.
One of the major concerns with controversial skincare ingredients is whether they are absorbed into the bloodstream. Some studies have produced evidence that octinoxate is present in human urine and breast milk. More research is needed to determine the full effects of octinoxate on the human body.
Is Octinoxate To Use on Congested skin?
Octinoxate is not necessarily linked to acne, however, anecdotally people do say that it worsens acne. Some research has found that octinoxate can produce adverse reactions in some skin types, particularly in sensitized skin types.
In What Product Is Octinoxate Used?
As you would expect you will find octinoxate in many sunscreen formulations, but you will also find it in foundations, hair dye, shampoo, nail polish, and lip balms. When it is used in cosmetics, the purpose of octinoxate is to keep the physical integrity of the product stable, especially when exposed to sunlight, making it a common ingredient in “long-lasting” cosmetic brands and products.
However, some new studies concerning this chemical have shown that when it’s used in sunscreen, it may degrade quicker than previously thought, which may reduce the effectiveness of the product and lead to long term problems, like hyperpigmentation. This is not the only concern that many skincare experts have about the use of octinoxate, and many have suggested being cautious about its utilization.
PubChem, ‘Compound Summary Octinoxate’, National Library of Medicine, National Center for Biotechnology Information.
Raffa, R, Pergolizzi, J, Taylor, R, & Kitzen, J, 2018. ‘Sunscreen bans: Coral reefs and skin cancer’, Journal of Clinical Pharmacy and Therapeutics, vol. 44, is. 1.
Adler, B & DeLeo, V, 2020. ‘Sunscreen Safety: a Review of Recent Studies on Humans and the Environment’, Journal of Photodermatology, vol. 9, pp.1-9. .
Ouchene, L, Litvinov, I & Netchiporouk, E, 2019. ‘Hawaii and Other Jurisdictions Ban Oxybenzone or Octinoxate Sunscreens Based on the Confirmed Adverse Environmental Effects of Sunscreen Ingredients on Aquatic Environments’, Journal of Cutaneous Medicine.