What's inside
What's inside
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
Water
Skin ConditioningDimethicone
EmollientZinc Oxide
Cosmetic ColorantEthylhexyl Methoxycinnamate
UV AbsorberDiisopropyl Sebacate
EmollientAlcohol Denat.
AntimicrobialIsododecane
EmollientEthylhexyl Salicylate
UV AbsorberSilica
AbrasiveOctocrylene
UV AbsorberIsopropyl Myristate
EmollientDiethylamino Hydroxybenzoyl Hexyl Benzoate
UV FilterTitanium Dioxide
Cosmetic ColorantPEG-9 Polydimethylsiloxyethyl Dimethicone
EmulsifyingDextrin Palmitate
EmulsifyingGlycerin
HumectantPolysilicone-15
UV FilterBis-Ethylhexyloxyphenol Methoxyphenyl Triazine
Skin ConditioningTrimethylsiloxysilicate
EmollientSodium Chloride
MaskingDipotassium Glycyrrhizate
HumectantScutellaria Baicalensis Root Extract
AstringentGeranium Robertianum Extract
AstringentSodium Hyaluronate
HumectantPPG-17
Skin ConditioningTriethoxycaprylylsilane
PEG-10 Dimethicone
Skin ConditioningIsostearic Acid
CleansingDisteardimonium Hectorite
StabilisingAluminum Hydroxide
EmollientStearic Acid
CleansingButylene Glycol
HumectantBHT
AntioxidantTocopherol
AntioxidantTrisodium EDTA
Sodium Metabisulfite
AntioxidantMyrtus Communis Leaf Extract
PerfumingWater, Dimethicone, Zinc Oxide, Ethylhexyl Methoxycinnamate, Diisopropyl Sebacate, Alcohol Denat., Isododecane, Ethylhexyl Salicylate, Silica, Octocrylene, Isopropyl Myristate, Diethylamino Hydroxybenzoyl Hexyl Benzoate, Titanium Dioxide, PEG-9 Polydimethylsiloxyethyl Dimethicone, Dextrin Palmitate, Glycerin, Polysilicone-15, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine, Trimethylsiloxysilicate, Sodium Chloride, Dipotassium Glycyrrhizate, Scutellaria Baicalensis Root Extract, Geranium Robertianum Extract, Sodium Hyaluronate, PPG-17, Triethoxycaprylylsilane, PEG-10 Dimethicone, Isostearic Acid, Disteardimonium Hectorite, Aluminum Hydroxide, Stearic Acid, Butylene Glycol, BHT, Tocopherol, Trisodium EDTA, Sodium Metabisulfite, Myrtus Communis Leaf Extract
Dimethicone
EmollientWater
Skin ConditioningZinc Oxide
Cosmetic ColorantAlcohol
AntimicrobialDiisopropyl Sebacate
EmollientIsododecane
EmollientOctocrylene
UV AbsorberEthylhexyl Salicylate
UV AbsorberC12-15 Alkyl Benzoate
AntimicrobialPEG/PPG-9/2 Dimethyl Ether
Skin ConditioningZea Mays Starch
AbsorbentTalc
AbrasiveSilica
AbrasiveIsopropyl Myristate
EmollientDiethylamino Hydroxybenzoyl Hexyl Benzoate
UV FilterTitanium Dioxide
Cosmetic ColorantPEG-9 Polydimethylsiloxyethyl Dimethicone
EmulsifyingDextrin Palmitate
EmulsifyingGlycerin
HumectantHomosalate
Skin ConditioningBis-Ethylhexyloxyphenol Methoxyphenyl Triazine
Skin ConditioningSodium Chloride
MaskingPEG/PPG-14/7 Dimethyl Ether
Skin ConditioningTrimethylsiloxysilicate
EmollientDipotassium Glycyrrhizate
HumectantCamellia Sinensis Extract
AntioxidantPotentilla Erecta Root Extract
Skin ConditioningCitrus Unshiu Peel Extract
MaskingSodium Acetylated Hyaluronate
HumectantLauryl Betaine
CleansingSoluble Collagen
HumectantEthylhexyl Triazone
UV AbsorberDisteardimonium Hectorite
StabilisingPEG-10 Dimethicone
Skin ConditioningIsostearic Acid
CleansingTriethoxycaprylylsilane
Polyglyceryl-6 Polyricinoleate
EmulsifyingAluminum Hydroxide
EmollientStearic Acid
CleansingTrisodium EDTA
PEG-6
HumectantTocopherol
AntioxidantBHT
AntioxidantButylene Glycol
HumectantBis-Butyldimethicone Polyglyceryl-3
CleansingSodium Metabisulfite
AntioxidantPhenoxyethanol
PreservativeSodium Benzoate
MaskingParfum
MaskingSynthetic Fluorphlogopite
Dimethicone, Water, Zinc Oxide, Alcohol, Diisopropyl Sebacate, Isododecane, Octocrylene, Ethylhexyl Salicylate, C12-15 Alkyl Benzoate, PEG/PPG-9/2 Dimethyl Ether, Zea Mays Starch, Talc, Silica, Isopropyl Myristate, Diethylamino Hydroxybenzoyl Hexyl Benzoate, Titanium Dioxide, PEG-9 Polydimethylsiloxyethyl Dimethicone, Dextrin Palmitate, Glycerin, Homosalate, Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine, Sodium Chloride, PEG/PPG-14/7 Dimethyl Ether, Trimethylsiloxysilicate, Dipotassium Glycyrrhizate, Camellia Sinensis Extract, Potentilla Erecta Root Extract, Citrus Unshiu Peel Extract, Sodium Acetylated Hyaluronate, Lauryl Betaine, Soluble Collagen, Ethylhexyl Triazone, Disteardimonium Hectorite, PEG-10 Dimethicone, Isostearic Acid, Triethoxycaprylylsilane, Polyglyceryl-6 Polyricinoleate, Aluminum Hydroxide, Stearic Acid, Trisodium EDTA, PEG-6, Tocopherol, BHT, Butylene Glycol, Bis-Butyldimethicone Polyglyceryl-3, Sodium Metabisulfite, Phenoxyethanol, Sodium Benzoate, Parfum, Synthetic Fluorphlogopite
Reviews
Ingredients Explained
These ingredients are found in both products.
Ingredients higher up in an ingredient list are typically present in a larger amount.
Aluminum Hydroxide is a form of aluminum. It can be naturally found in nature as the mineral gibbsite. In cosmetics, Aluminum Hydroxide is used as a colorant, pH adjuster, and absorbent.
As a colorant, Aluminum Hydroxide may add opacity, or reduce the transparency. Aluminum hydroxide is contains both basic and acidic properties.
According to manufacturers, this ingredient is an emollient and humectant. This means it helps hydrate the skin.
In medicine, this ingredient is used to help relieve heartburn and help heal ulcers.
There is currently no credible scientific evidence linking aluminum hydroxide in cosmetics to increased cancer risk.
Major health organizations allow the use of aluminum hydroxide in personal care products and have not flagged it as a carcinogenic risk at typical usage levels.
Learn more about Aluminum HydroxideBHT is a synthetic antioxidant and preservative.
As an antioxidant, it helps your body fight off free-radicals. Free-radicals are molecules that may damage your skin cells.
As a preservative, it is used to stabilize products and prevent them from degrading. Specifically, BHT prevents degradation from oxidation.
The concerns related to BHT come from oral studies; this ingredient is currently allowed for use by both the FDA and EU.
However, it was recently restricted for use in the UK as of April 2024.
Learn more about BHTThis ingredient is better known as bemotrizinol or Tinosorb S and is one of the best broad-spectrum UV filters in modern sunscreen.
It works by absorbing UV light across a whole range (280-400 nm) with peaks around 310 nm (UVB) and 340-345 nm (UVA). This means it covers UVB plus the deeper UVA wavelengths that drive photoaging and pigmentation.
Another pro?
It's exceptionally photostable, barely degrades in sunlight, and acts as a "bodyguard" for less stable filters.
That's why you'll see it paired with avobenzone or octinoxate; this team up ensures they keep working through sun exposure.
Safety reviews have been reassuring across the board. This ingredient shows low absorption through the skin, rarely irritates, and lab studies found it doesn't act like a hormone in the body (a concern that's been raised about some older sunscreen filters).
On maximum concentrations:
In 2026, the US F.D.A finally added it as an OTC sunscreen ingredient at concentrations up to 6% for adults / children 6 months and older
Learn more about Bis-Ethylhexyloxyphenol Methoxyphenyl TriazineButylene 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.
Learn more about Butylene GlycolDextrin Palmitate is an oil-loving texture helper made by bonding palmitic acid onto Dextrin. It's main roles are to turn liquid oils into spreadable gels and prevent ingredients from separating.
It also lends a silky, non-greasy slip that makes products feel more elegant.
Typical use concentrations range from 0.5-5%, but can go up to 10% depending on how firm the gel is.
Because it's an ester built on a fatty acid, it may not be fungal acne safe.
Learn more about Dextrin PalmitateDiethylamino Hydroxybenzoyl Hexyl Benzoate (DHHB) is a chemical UV-A absorber. It is formulated for high UVA protection (320-400 nm).
DHHB is well-liked for:
DHHB has been approved by the EU, Japan, Taiwan, and South America for use up to 10%. Unfortunately, it has not been approved for use in the US or Canada due to slow regulatory processes.
This ingredient is soluble in oils, fats, and lipids.
Learn more about Diethylamino Hydroxybenzoyl Hexyl BenzoateWe don't have a description for Diisopropyl Sebacate yet.
Dimethicone is a type of synthetic silicone created from natural materials such as quartz. It is also known as polydimethylsiloxane.
What it does:
Dimethicone comes in different viscosities:
Depending on the viscosity, dimethicone has different properties.
Ingredients lists don't always show which type is used, so we recommend reaching out to the brand if you have questions about the viscosity.
This ingredient is unlikely to cause irritation because it does not get absorbed into skin. However, people with silicone allergies should be careful about using this ingredient.
Note: Dimethicone may contribute to pilling. This is because it is not oil or water soluble, so pilling may occur when layered with products. When mixed with heavy oils in a formula, the outcome is also quite greasy.
Learn more about DimethiconeDipotassium Glycyrrhizate comes from licorice root.
Extracts of licorice have demonstrated to have antibacterial, anti‐inflammatory, antiviral, antioxidant properties.
One component, glabridin, has extra potent antioxidant and soothing properties. It has also been found to block pigmentation from UVB rays in guinea pigs.
Licorice Root also contains a flavonoid. Flavonoids are a natural substance from in plants. Flavonoids also have antioxidant properties.
Another component, glycyrrhizin, has been found to have anti-inflammatory and antimicrobial benefits. This may make licorice root extract effective at treating acne. However, more research is needed to support this.
Liquiritin is one of the flavone compounds found in licorice. It has been found to help lighten skin by preventing tyrosinase from reacting with tyrosine. When the two react, protein is converted to melanin. Melanin is the substance in your body that gives your features pigmentation.
Licorice root is native to Southern Europe and Asia. It has been used in traditional Chinese medicine to help with respiratory issues.
Learn more about Dipotassium GlycyrrhizateDisteardimonium Hectorite comes from the clay mineral named hectorite. It is used to add thickness to a product.
It can also help stabilize a product by helping to disperse other ingredients.
Hectorite is a rare, white clay mineral.
Learn more about Disteardimonium HectoriteEthylhexyl Salicylate (also called Octisalate or Octyl Salicylate) is an oil-soluble organic UV filter that's been used in sunscreen since the 1950's.
It absorbs UVB light in the 280-320 nm range with a peak absorbance around 306 nm.
You'll often see it paired with other UV filters to boost overall SPF because octisalate is a fairly week filter on its own.
The reason you'll see it so often is because it can help solubilize and stabilize the trickier filters like oxybenzone and avobenzone.
Unlike these filters, octisalate has pretty good photostability and doesn't create skin-damaging free radicals when exposed to sunlight.
The fatty-alcohol part of the molecule also gives it a light, emollient feel so it doubles as a nice texture enhancer.
Usage levels vary around the world:
Safety-wise, this ingredient has a pretty reassuring track record. The EU's Scientific Committee on Consumer Products (SCCP) found very low skin penetration in human skin tests and negative results for irritation, phototoxicity, and photoallergy.
The real-world allergy risk is pretty low too; a 2012 European study of 1,031 people recorded only 2 reactions to it (a rate of 0.19%).
You might have seen scary headlines about sunscreen getting into your blood.
In 2019, the FDA found that several chemical filters can absorb through the skin and show up in the bloodstream at small but measurable levels.
Here's the important part: these tiny levels are just a cutoff the FDA uses to decide which ingredients need more testing and doesn't mean anything harmful was found.
The researchers were clear that the results are no reason to stop wearing sunscreen.
Learn more about Ethylhexyl SalicylateGlycerin (or glycerol) is a compound naturally found in your skin. It's a powerhouse humectant that pulls water into the stratum corneum.
Topically, glycerin does several things at once:
Your skin makes glycerin on its own (mostly from sebaceous oil breakdown) and shuttles it to your outermost layer of skin, or your epidermis, via aquaporin-3.
Aquaporin-3 is a transporter that is essential for normal skin hydration, elasticity, and repair. Interestingly, mice lacking in AQP3 have dry and less elastic skin that can be fully corrected with glycerin.
This ingredient is non-irritating, plays well with almost every ingredient, and works across all skin types. Typical use is anywhere between 3-10% but can go up to 79% in some leave-on products.
Just know very high concentrations (>40%) can feel tacky in low humidity.
Glycerin is the name for this ingredient in American English. British English uses Glycerol/Glycerine.
Learn more about GlycerinIsododecane is a fragrance, emollient, and solvent.
As an emollient, it helps your skin stay soft and hydrated. Emollients help trap moisture into your skin.
Isododecane's role as a solvent makes it a great texture enhancer. It spreads smoothly on skin and does not leave a sticky feeling behind. Isododecane also helps prevent color transfer in makeup products.
Isododecane is not absorbed into skin.
The chemical name for this ingredient is 2,2,4,6,6-PENTAMETHYLHEPTANE.
Learn more about IsododecaneIsopropyl Myristate is an ester made by combining isopropyl alcohol with myristic acid.
It is primarily an emollient and penetration enhancer that gives products a lightweight, silky feel without the heaviness of oils.
This ingredient is generally considered non-toxic, non-irritating, and has low absorption potential.
You might have heard that this ingredient clogs pores. This reputation comes from the older rabbit ear studies which are more sensitive than human skin to clogging.
Dermatologist Dr. Zoe Draelos has also confirmed in a peer-reviewed paper that products containing comedogenic ingredients are not necessarily comedogenic themselves.
A small subset of people (~2%) may experience contact sensitivity so patch testing is a reasonable idea if you have reactive skin.
Since this ingredient is an ester of myristic acid (a C14 fatty acid), it falls within the carbon chain range that is known to feed Malassezia. This ingredient may not be fungal acne safe.
Learn more about Isopropyl MyristateIsostearic Acid is a fatty acid and a structural cousin of stearic acid. It is an emulsifier.
The branched structure of this ingredient enhances fluidity and gives it a lighter, less greasy feel compared to other fatty acids. It helps improve texture and consistency because it prevents oil and water phases from separating.
This ingredient is sourced from plant-based oils like soybean or rapeseed.
Clinical studies found no signs of irritation from this ingredient.
Since Isostearic Acid is an 18-carbon fatty acid, it is in the range that Malassezia can feed on. This ingredient may not be fungal acne safe.
You might have seen sources that this ingredient is comedogenic. The original comedogenic testing on rabbit ear actually tested the ester, Isopropyl Isostearate and not Isostearic acid itself. There has been no comedogenic testing done on this ingredient, but it may be worth patch testing if you have acne-prone skin.
Learn more about Isostearic AcidOctocrylene is an oil-soluble organic UV filter that mainly absorbs UVB and short wave UVA II light.
Its real superpower is teamwork: octocrylene is remarkably photostable and is most famous for stabilizing avobenzone (the workhorse UVA filter).
This ingredient is commonly used to enhance both UVB and UVA protection due to its unique property in stabilizing avobenzone. It also pulls double duty by boosting water resistance and giving formulas a smooth, spreadable feel.
The EU's Scientific Committee on Consumer Safety (SCCS) has deemed octocrylene to be safe as a UV-filter at concentrations up to 10% (capped at 9% in propellant sprays). The US also permits it up to 10%.
Two things worth knowing:
You'll usually see this ingredient used in concentrations between 2-10% (higher amounts when used as a stabilizer for avobenzone).
Learn more about OctocrylenePeg-10 Dimethicone is silicone with conditioner and emulsifier properties. It mostly acts as an emollient in skincare and and humectant in haircare.
According to the manufacturer, acidic formulations decrease the stability of this ingredient. It works best in neutral or near neutral formulations.
PEG-9 Polydimethylsiloxyethyl Dimethicone is a type of silicone.
Silica, also known as silicon dioxide, is a naturally occurring mineral. It is used as a fine, spherical, and porous powder in cosmetics.
Though it has exfoliant properties, the function of silica varies depending on the product.
The unique structure of silica enhances the spreadability and adds smoothness, making it a great texture enhancer.
It is also used as an active carrier, emulsifier, and mattifier due to its ability to absorb excess oil.
In some products, tiny microneedles called spicules are made from silica or hydrolyzed sponge. When you rub them in, they lightly polish away dead skin layers and enhance the penetration of active ingredients.
Learn more about SilicaChances are, you eat sodium chloride every day. Sodium Chloride is also known as table salt. This ingredient has many purposes in skincare: thickener, emulsifier, and exfoliator.
You'll most likely find this ingredient in cleansers where it is used to create a gel-like texture. As an emulsifier, it also prevents ingredients from separating.
You might see people debate whether Sodium Chloride is comedogenic, but there actually haven't been any comedogenic tests done on it. Either way, the overall formulation of a product matters a lot more than any single ingredient.
You might see this ingredient used in scrubs as a primary exfoliating ingredient.
Learn more about Sodium ChlorideSodium metabisulfite is also known as Sodium Pyrosulfite. It is a preservative, antioxidant, and disinfectant.
As a preservative, it helps stabilize cosmetic formulas without affecting their color or scent.
Stearic Acid is a fatty acid that is already found in your skin. It's one of the free fatty acids that works alongside ceramides and cholesterols to maintain your barrier.
In cosmetics, it is a multitasker:
Safety-wise, the CIR Expert Panel has concluded it to be safe in cosmetics when formulated to be non-irritating and non-sensitizing.
Free stearic acid is a C18 fatty acid that the Malassezia yeast can substrate, so this ingredient may not be fungal acne safe.
Learn more about Stearic AcidTitanium dioxide is a mineral UV filter widely used in sunscreens and cosmetics.
It is one of only two UV filters officially classified as “mineral” by regulatory agencies, the other being zinc oxide.
Titanium dioxide provides broad-spectrum protection mostly in the UVB and UVAII range, with some protection in the UVAI range.
While its UVA protection isn’t as strong as zinc oxide’s, the difference is minor.
A common myth is that mineral UV filters reflect UV light. However, modern research shows titanium dioxide absorbs UV radiation like chemical filters (~95% absorption & 5% reflection).
Thanks to its non-irritating nature, titanium dioxide is suitable for sensitive, acne-prone, or redness-prone skin. It is unlikely to cause "eye sting" like other sunscreen ingredients.
A major drawback of this ingredient is its white cast and thick texture. This is why mineral sunscreens often leave a white cast and are less cosmetically elegant than chemical/hybrid sunscreens.
To improve white cast and spreadability, micronized or nano-sized titanium dioxide is often used.
There are ongoing concerns surrounding nano-titanium oxide's impact on marine ecosystems.
There is no conclusive evidence that any form of titanium oxide (or any other sunscreen ingredients) will cause harm to marine ecosystems or coral reefs. The science is still developing but many consumers are keeping a close eye on this issue.
Please note, many destinations have reef-safety sunscreen rules. For instance, the U.S. Virgin Islands advises all visitors to use non-nano mineral sunscreens.
Nano mineral sunscreens once raised safety concerns about absorption into skin.
Extensive research has shown that they do not penetrate healthy or damaged skin; they remain safely on the surface and the top layer of dead skin (stratum corneum).
You'll likely find titanium dioxide bundled with alumina, silica, or dimethicone. These ingredients help make titanium dioxide highly photostable; this prevents it from interacting with other formula components under UV light.
Learn more about Titanium DioxideTocopherol 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.
Learn more about TocopherolTriethoxycaprylylsilane is a silicon-based surface modifier that makes sunscreens feel silky and makeup stay put.
Its main job is to coat mineral particles like titanium dioxide, zinc oxide, and color pigments in a thin, oily layer so they spread smoothly, don't clump, and stick to skin better.
This ingredient is typically used at low levels (up to 2.5% in eyeshadow and 1% in lipstick).
Learn more about TriethoxycaprylylsilaneThis silicone is an emollient. Emollients create a thin film on the skin to prevent moisture from escaping.
It is not soluble in water and helps increase water-resistance in products.
According to a manufacturer, it can blend seamlessly with silicone oils, such as Cyclopentasiloxane.
Learn more about TrimethylsiloxysilicateTrisodium EDTA is one of those quietly essential helper ingredients that most people have never heard of. You'll most likely spot it near the end of ingredient lists in almost every category of skincare.
So what does it actually do?
Its main job is chelation; this is a fancy word to say it grabs onto metal ions and neutralizes them. This is because even purified water in cosmetics contains trace amounts of metals that can cause big problems in a formula.
These trace metals can break down actives faster, cause discoloration, promote rancidity in oils, and make preservatives less effective. Trisodium EDTA binds to these metals and takes them out of the equation so your products can stay stable and effective for longer.
There's also an added bonus: by neutralizing the metals ions that bacteria need to thrive, this ingredient also acts as a preservative booster.
The Cosmetic Ingredient Review has concluded this ingredient to be safe as used in cosmetic formulations. It is not considered an irritant, sensitizer, and is barely absorbed through the skin.
Learn more about Trisodium EDTAWater. 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!
Learn more about WaterZinc Oxide is a mineral broad-spectrum UV filter; it is the broadest UVA and UVB reflector approved by the FDA. It also has skin protectant and skin soothing properties.
Zinc oxide is one of the most effective broad-spectrum UV filters. It protects against UVB, UVAII, and UVAI. In comparison to its counterpart titanium dioxide, zinc oxide provides uniform and extended UVA protection.
Another great benefit? This ingredient is highly photostable so it won't degrade easily under sunlight.
A common myth is that mineral UV filters are widely believed to primarily reflect UV light.
However, modern research shows titanium dioxide absorbs UV radiation like chemical filters (~95% absorption & 5% reflection).
Zinc oxide has great skin soothing properties so you'll likely find this in sunscreens formulated for sensitive skin or babies/children. It is unlikely to cause "eye sting" like other sunscreen ingredients.
Regulatory agencies consider zinc oxide to be non-toxic and safe. It has also been shown to not penetrate the skin.
Unfortunately, this ingredient does leave a visible white cast. This is why mineral sunscreens are often less cosmetically elegant than chemical or hybrid ones.
In cosmetics, zinc oxide can be found in both non-nano and nano-sized forms. The nano version is used to reduce white cast and improve the texture of sunscreen formulas.
There are ongoing concerns surrounding nano-zinc oxide's impact on marine ecosystems and whether it can be absorbed into skin.
Regarding marine ecosystems and coral reefs, there is no conclusive evidence that any form of zinc oxide (or any other sunscreen ingredients) will cause harm. The science is still developing but many consumers are keeping a close eye on this issue.
Please note, many destinations have reef-safety sunscreen rules. For instance, the U.S. Virgin Islands advises all visitors to use non-nano mineral sunscreens.
There has also been some stir about whether micronized or nano zinc oxide has potential photoxicity and absorption through the skin/lungs.
An in-vitro (done in a test tube or petri dish) study demonstrated micronized zinc oxide to have potential phototoxicity. There's no need to fret; the EU Commission's Scientific Committee on Consumer Safety has stated, "The relevance of these findings needs to be clarified by appropriate investigations in vivo." Or in other words, further studies done on living organisms are needed to prove this.
Current research shows zinc oxide nanoparticles do not penetrate intact or sunburned skin. They either remain on the surface or in the outermost layer of dead skin (stratum corneum).
Zinc oxide is one of only two classified mineral UV filters with titanium dioxide being the other one.
Fun fact: Zinc has been used throughout history as an ingredient in paint and medicine. An Indian text from 500BC is believed to list zinc oxide as a salve for open wound. The Ancient Greek physician Dioscorides has also mentioned the use of zinc as an ointment in 1AD.
Learn more about Zinc Oxide