Amaterasun 100% Physical Soothing Sunscreen SPF50+ PA++++ Versus Npure Noni Beat The Sun Physical Sunscreen SPF 50+
This hybrid sunscreen covers the full UV range and blocks ~98% of UVB at SPF 50.
This mineral sunscreen covers the full UV range and blocks ~98% of UVB at SPF 50.
What's inside
What's inside
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
Water
Skin ConditioningZinc Oxide
Cosmetic ColorantCyclopentasiloxane
EmollientPropanediol
SolventDicaprylyl Carbonate
EmollientDisiloxane
Skin ConditioningPropylheptyl Caprylate
EmollientNiacinamide
SmoothingLauryl Polyglyceryl-3 Polydimethylsiloxyethyl Dimethicone
Skin Conditioning1,2-Hexanediol
Skin ConditioningNymphaea Alba Flower Extract
Skin ConditioningCeramide NP
Skin ConditioningPanthenol
Skin ConditioningGlycyrrhiza Glabra Root Extract
BleachingPhospholipids
Skin ConditioningRosmarinus Officinalis Leaf Extract
AntimicrobialHelianthus Annuus Seed Oil
EmollientLactobacillus Ferment
Skin ConditioningCholesterol
EmollientTocopheryl Acetate
AntioxidantSolanum Lycopersicum Fruit Extract
AntioxidantDipotassium Glycyrrhizate
HumectantGlycerin
HumectantTremella Fuciformis Extract
HumectantTocopherol
AntioxidantEthyl Ferulate
AntioxidantIsododecane
EmollientAscorbyl Glucoside
AntioxidantEthylhexyl Palmitate
EmollientHydrogenated Lecithin
EmulsifyingSodium Palmitoyl Proline
Skin Conditioning3-O-Ethyl Ascorbic Acid
Skin ConditioningDisteardimonium Hectorite
StabilisingMagnesium Sulfate
Polyglyceryl-2 Dipolyhydroxystearate
Skin ConditioningDipropylene Glycol
HumectantIsopropyl Myristate
EmollientChitosan
Butylene Glycol
HumectantTrimethylsiloxysilicate
EmollientAcrylates/Polytrimethylsiloxymethacrylate Copolymer
Skin ConditioningYeast Extract
Skin ConditioningPentylene Glycol
Skin ConditioningCyanocobalamin
Skin ConditioningPolyhydroxystearic Acid
EmulsifyingDimethicone
EmollientHydroxyacetophenone
AntioxidantTriethoxycaprylylsilane
Polyglyceryl-4 Diisostearate/Polyhydroxystearate/Sebacate
EmulsifyingLecithin
EmollientOctyldodecanol
EmollientIsostearic Acid
CleansingCI 77288
Cosmetic ColorantPolyglyceryl-3 Polyricinoleate
EmulsifyingNeopentyl Glycol Diethylhexanoate
EmollientEthyl Hexanediol
SolventMagnesium Chloride
Calcium Gluconate
HumectantPyridoxine Hcl
Skin ConditioningPolyglyceryl-10 Laurate
Skin ConditioningEthylhexylglycerin
Skin ConditioningWater, Zinc Oxide, Cyclopentasiloxane, Propanediol, Dicaprylyl Carbonate, Disiloxane, Propylheptyl Caprylate, Niacinamide, Lauryl Polyglyceryl-3 Polydimethylsiloxyethyl Dimethicone, 1,2-Hexanediol, Nymphaea Alba Flower Extract, Ceramide NP, Panthenol, Glycyrrhiza Glabra Root Extract, Phospholipids, Rosmarinus Officinalis Leaf Extract, Helianthus Annuus Seed Oil, Lactobacillus Ferment, Cholesterol, Tocopheryl Acetate, Solanum Lycopersicum Fruit Extract, Dipotassium Glycyrrhizate, Glycerin, Tremella Fuciformis Extract, Tocopherol, Ethyl Ferulate, Isododecane, Ascorbyl Glucoside, Ethylhexyl Palmitate, Hydrogenated Lecithin, Sodium Palmitoyl Proline, 3-O-Ethyl Ascorbic Acid, Disteardimonium Hectorite, Magnesium Sulfate, Polyglyceryl-2 Dipolyhydroxystearate, Dipropylene Glycol, Isopropyl Myristate, Chitosan, Butylene Glycol, Trimethylsiloxysilicate, Acrylates/Polytrimethylsiloxymethacrylate Copolymer, Yeast Extract, Pentylene Glycol, Cyanocobalamin, Polyhydroxystearic Acid, Dimethicone, Hydroxyacetophenone, Triethoxycaprylylsilane, Polyglyceryl-4 Diisostearate/Polyhydroxystearate/Sebacate, Lecithin, Octyldodecanol, Isostearic Acid, CI 77288, Polyglyceryl-3 Polyricinoleate, Neopentyl Glycol Diethylhexanoate, Ethyl Hexanediol, Magnesium Chloride, Calcium Gluconate, Pyridoxine Hcl, Polyglyceryl-10 Laurate, Ethylhexylglycerin
Water
Skin ConditioningZinc Oxide
Cosmetic ColorantCoco-Caprylate/Caprate
EmollientPropanediol
SolventCentella Asiatica Leaf Water
Skin ConditioningPropylheptyl Caprylate
EmollientGlycerin
HumectantMethyl Methacrylate Crosspolymer
Dicaprylyl Ether
EmollientDimethicone/Vinyl Dimethicone Crosspolymer
Skin ConditioningPolyhydroxystearic Acid
Emulsifying1,2-Hexanediol
Skin ConditioningPanthenol
Skin ConditioningPentylene Glycol
Skin ConditioningDibutyl Adipate
EmollientAllantoin
Skin ConditioningTocopherol
AntioxidantBisabolol
AntioxidantBifida Ferment Lysate
Skin ConditioningNiacinamide
SmoothingPotassium Cetyl Phosphate
EmulsifyingTriethoxycaprylylsilane
Polymethylsilsesquioxane
C14-22 Alcohols
Emulsion StabilisingAmmonium Polyacryloyldimethyl Taurate
Emulsion StabilisingHydroxyacetophenone
AntioxidantSaccharide Isomerate
HumectantC12-20 Alkyl Glucoside
EmulsifyingPolyglyceryl-10 Myristate
Skin ConditioningHydroxypropyl Methylcellulose Stearoxy Ether
Polyacrylate Crosspolymer-6
Emulsion StabilisingSodium Polyacrylate
AbsorbentCaprylic/Capric Triglyceride
MaskingDipotassium Glycyrrhizate
HumectantButylene Glycol
HumectantPolyether-1
Behenyl Alcohol
EmollientArachidyl Glucoside
EmulsifyingEthylhexylglycerin
Skin ConditioningSodium Citrate
BufferingCitric Acid
BufferingArginine
MaskingXanthan Gum
EmulsifyingTremella Fuciformis Extract
HumectantSodium Hyaluronate
HumectantCamellia Sinensis Leaf Extract
AntimicrobialSaccharomyces Ferment Filtrate
HumectantPolysorbate 60
EmulsifyingYeast Extract
Skin ConditioningCyanocobalamin
Skin ConditioningSodium Lactate
BufferingSodium PCA
Humectant4-T-Butylcyclohexanol
MaskingAnthemis Nobilis Flower Extract
MaskingHydrogenated Lecithin
EmulsifyingGlycine
BufferingGlucose
HumectantFructose
HumectantInositol
HumectantWater, Zinc Oxide, Coco-Caprylate/Caprate, Propanediol, Centella Asiatica Leaf Water, Propylheptyl Caprylate, Glycerin, Methyl Methacrylate Crosspolymer, Dicaprylyl Ether, Dimethicone/Vinyl Dimethicone Crosspolymer, Polyhydroxystearic Acid, 1,2-Hexanediol, Panthenol, Pentylene Glycol, Dibutyl Adipate, Allantoin, Tocopherol, Bisabolol, Bifida Ferment Lysate, Niacinamide, Potassium Cetyl Phosphate, Triethoxycaprylylsilane, Polymethylsilsesquioxane, C14-22 Alcohols, Ammonium Polyacryloyldimethyl Taurate, Hydroxyacetophenone, Saccharide Isomerate, C12-20 Alkyl Glucoside, Polyglyceryl-10 Myristate, Hydroxypropyl Methylcellulose Stearoxy Ether, Polyacrylate Crosspolymer-6, Sodium Polyacrylate, Caprylic/Capric Triglyceride, Dipotassium Glycyrrhizate, Butylene Glycol, Polyether-1, Behenyl Alcohol, Arachidyl Glucoside, Ethylhexylglycerin, Sodium Citrate, Citric Acid, Arginine, Xanthan Gum, Tremella Fuciformis Extract, Sodium Hyaluronate, Camellia Sinensis Leaf Extract, Saccharomyces Ferment Filtrate, Polysorbate 60, Yeast Extract, Cyanocobalamin, Sodium Lactate, Sodium PCA, 4-T-Butylcyclohexanol, Anthemis Nobilis Flower Extract, Hydrogenated Lecithin, Glycine, Glucose, Fructose, Inositol
Reviews
Ingredients Explained
These ingredients are found in both products.
Ingredients higher up in an ingredient list are typically present in a larger amount.
1,2-Hexanediol is a synthetic liquid and another multi-functional powerhouse.
It is a:
- Humectant, drawing moisture into the skin
- Emollient, helping to soften skin
- Solvent, dispersing and stabilizing formulas
- Preservative booster, enhancing the antimicrobial activity of other preservatives
Butylene 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 GlycolCyanocobalamin is the manufactured version of vitamin B12. It has skin soothing, antioxidant, and barrier protecting properties. Topical cyanocobalamin is used to treat skin irritation and atopic dermatitis.
Dipotassium 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 GlycyrrhizateEthylhexylglycerin is created from glycerin. It is a multitasker ingredient that:
The CIR Expert Panel found minimal skin absorption or sensitization of any kind in a safety assessment. Though this ingredient is considered well-tolerated, a small number of cases of allergic dermatitis have been published since 2002. Just be sure to patch test if you are unsure.
Industry-reported use ranges from 8% in rinse-off products and 2% in leave-on formulations.
Learn more about EthylhexylglycerinGlycerin (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 GlycerinHydrogenated Lecithin is a more stable version of lecithin.
It's made by taking lecithin (a phospholipid commonly found in soybeans and egg yolks) and hydrogenating it. This just means the unsaturated fatty acids are turned into saturated ones so they don't go bad as easily.
This ingredient is an emollient, emulsifier, and penetration enhancer. As an emollient, it helps soften and hydrate skin by trapping moisture within. As an emulsifier, it prevents oil and water ingredients from separating.
Hydrogenated Lecithin can form tiny spherical structures made of phospholipid bilayers called liposomes. These liposomes are able to capture compounds inside their structure and deliver them through the skin barrier.
Because phospholipids are a natural component of our cell membranes, this ingredient is inherently compatible with skin.
A 2021 study found lecithin-based surfactants were less harsh and more tolerable comared to Sodium Lauryl Sulfate (SLS).
Learn more about Hydrogenated LecithinHydroxyacetophenone is a small phenolic molecule that earns its place in a formulas as an antioxidant and preservative booster.
As a phenol, it is able to neutralize free radicals to protect both the product and the skin from oxidative stress.
Though it can't kill microbes on its own, it works as a good supporting agent when combined with other preservatives like Phenoxyethanol or 1,2-Hexanediol.
This ingredient naturally occurs as piceol in Norwegian spruce needles (~0.4-1.1% dry weight and in cloudberries). Though the cosmetic-grade material is synthesized for purity and consistency.
You'll usually see it used at low levels and suppliers recommend up to 1% added to a water phase.
Safety testing was done at concentrations like 0.05% in SPF products and 0.5% in a Human Repeated Insult Patch Test. The safety evidence is assuring; this ingredient is safe for cosmetics in current use and also holds safety status as a food flavoring as well.
An honest caveat: the "soothing" and "anti-inflammatory" claims come mostly from supplier marketing rather than published clinical trials. The Cosmetic Ingredient Review's own literature search found no useful efficacy studies on this ingredient.
So the antioxidant and preservative-boosting roles are the well supported ones while the calming benefit is plausible but thinly evidenced.
Overall, this is a well-tolerated, low-irritation multitasker that quietly helps a formula stay fresh and stable.
Learn more about HydroxyacetophenoneNiacinamide is a multitasking form of vitamin B3 that strengthens the skin barrier, reduces pores and dark spots, regulates oil, and improves signs of aging.
And the best part? It's gentle and well-tolerated by most skin types, including sensitive and reactive skin.
You might have heard of "niacin flush", or the reddening of skin that causes itchiness. Niacinamide has not been found to cause this.
In very rare cases, some individuals may not be able to tolerate niacinamide at all or experience an allergic reaction to it.
If you are experiencing flaking, irritation, and dryness with this ingredient, be sure to double check all your products as this ingredient can be found in all categories of skincare.
When incorporating niacinamide into your routine, look out for concentration amounts. Typically, 5% niacinamide provides benefits such as fading dark spots. However, if you have sensitive skin, it is better to begin with a smaller concentration.
When you apply niacinamide to your skin, your body converts it into nicotinamide adenine dinucleotide (NAD). NAD is an essential coenzyme that is already found in your cells as "fuel" and powers countless biological processes.
In your skin, NAD helps repair cell damage, produce new healthy cells, support collagen production, strengthen the skin barrier, and fight environmental stressors (like UV and pollution).
Our natural NAD levels start to decline with age, leading to slower skin repair, visible aging, and a weaker skin barrier. By providing your skin niacinamide, you're recharging your skin's NAD levels. This leads to stronger, healthier, and younger looking skin.
Another name for vitamin B3 is nicotinamide. This vitamin is water-soluble and our bodies don't store it. We obtain Vitamin B3 from either food or skincare. Meat, fish, wheat, yeast, and leafy greens contain vitamin B3.
The type of niacinamide used in skincare is synthetically created.
Learn more about NiacinamidePanthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.
There are two forms of panthenol: D and L.
D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.
Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):
Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.
This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.
Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.
This ingredient is also referred to as pro-vitamin B5.
Learn more about PanthenolPentylene Glycol (1,2-pentanediol) is a multitasking little diol with three main roles in a formula:
Research on alkanediols (the family pentylene glycol belongs to) show they work by disrupting microbial cell membranes. This disruption helps the primary preservative system in a product work more effectively at lower doses.
On the safety side, the Cosmetic Ingredient Review Expert Panel has concluded this ingredient to be safe as used in current cosmetic practices + concentrations.
Typical use levels in a formula run about 1-5%.
Learn more about Pentylene GlycolPolyhydroxystearic Acid is a vegetable-derived soft wax made from castor oil. It's an emulsion stabilizer, thickener, and film former.
You'll likely see it in sunscreens because it helps disperse pigments and UV-reflecting minerals like titanium dioxide and zinc oxide evenly.
Depending on the concentration, it can drastically change the texture of a product from pasty solid (like lipstick) to sprayable liquid.
The CIR Expert Panel for Cosmetic Ingredient Safety has concluded this ingredient to be safe in cosmetics. The highest reported use concentration is 14.2% in lipsticks.
Learn more about Polyhydroxystearic AcidPropanediol is an all-star ingredient. It softens, hydrates, and smooths the skin.
It’s often used to:
Propanediol is not likely to cause sensitivity and considered safe to use. It is derived from corn or petroleum with a clear color and no scent.
Learn more about PropanediolWe don't have a description for Propylheptyl Caprylate yet.
Tocopherol 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 TocopherolTremella Fuciformis Extract comes from the tremella fuciformis mushroom, also known as snow mushroom or white jelly mushroom.
The snow mushroom has moisturizing and antioxidant properties.
Snow mushroom is rich in polysaccharides, giving it moisturizing benefits. As a humectant, snow mushroom helps draw moisture from the air to the skin. Polysaccharides are able to mimic our skin's natural carbohydrates to help the skin retain water.
Snow mushroom has been shown to help with anti-aging due to its antioxidants. It increases the presence of superoxide dismutase in our brain and liver. Superoxide is a by-product of oxygen metabolism. It left unregulated, superoxide causes cell damage. Thus, superoxide dismutase acts as an antioxidant to protect our living cells.
Another study from 2016 showed snow mushroom extract blocks the skin from creating melanin when exposed to UVB. Thus, it may help protect against the signs of aging from sun exposure. However, more studies are needed to confirm this. Another study from 2021 found snow mushroom to protect against UVA damage as well.
This white mushroom is native to Asian countries such as China, Korea, Japan, and Thailand. It is a common ingredient in traditional Chinese cuisine and medicine.
Learn more about Tremella Fuciformis ExtractTriethoxycaprylylsilane 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 TriethoxycaprylylsilaneWater. 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 WaterYeast extract is a silky, clear liquid derived from yeast (usually Saccharomyces cerevisiae or Torula yeast).
This ingredient has plenty of skin benefits:
Bioferments of yeast and soy have been found to reduce hyperpigmentation at low levels.
Yeast extract is fungal acne safe because it's made up of amino acids, peptides, B vitamins, and nucleotides (not the C11-C24 fatty acids that Malassezia needs to thrive).
The "yeast" in the name can be misleading, but FA safety is about chemical composition and not ingredient origin.
Learn more about Yeast ExtractZinc Oxide (ZO) is a mineral broad-spectrum UV filter and the broadest-spectrum filter recognized by the FDA. It covers everything from UVB through to long-wave UVA.
On top of sun protection, it has skin protectant and skin-soothing properties too.
Here's a myth worth busting: mineral filters are usually described as working by "reflecting" or "bouncing" UV off your skin.
That's mostly not true: when researchers actually measured it, ZO and Titanium Dioxide reflect only about 4-5% of UV (less than SPF 2 worth of protection).
The vast majority of the work (~95%) is done by absorption, similar to chemical UV filters. ZO is a semiconductor that absorbs UV photos through its energy band gap.
So the old "physical blocker vs. chemical absorber" framing is really an oversimplification.
Zinc Oxide is one of the most effective broad-spectrum UV filters out there. It protects across UVB, UVA2, and UVA1 with a flat, even absorption curve across the whole UVA-UVB range.
That uniform UVA coverage is its standout feature; titanium dioxide skews more toward UVB as its particle size drops so ZO gives more consistent and extended UVA protection.
It's also very photostable. As an inorganic oxide, ZO doesn't break down in sunlight the way some organic filters can, so it holds up over a day of wear.
This ingredient is gentle and soothing, making it go-to for sunscreens aimed at sensitive skin, rosacea, or ecezma-prone skin, babies, and children.
It's also unlikely to cause the "eye sting" that some sunscreen ingredients are known for, and regulatory agencies broadly consider it non-toxic and safe for topical use.
Beyond sun protection, ZO is also a recognized OTC skin protectant. It forms a breathable barrier that shields skin from moisture and irritation while supporting healing. This is why you'll see it as a classic active in diaper rash creams.
The only downside to ZO is that it can leave a visible white cast, especially on deeper skin tones. This is the main reason mineral sunscreens have historically felt less cosmetically elegant than chemical or hybrid formulas.
Zinc Oxide comes in both non-nano and nano forms. The dividing line is 100nm and anything under is classified as a nanomaterial by the EU.
The nano version scatters less visible light which cuts down white case and gives a lighter, more wearable texture.
Another thing worth understanding about formulation:
Uncoated ZO has some inherent photocatalytic activity. This just means it can generate reactive oxygen species under UV. It's exactly why cosmetic-grade ZO is almost always surface-coated; this coating suppresses that reactivity and improves how the powder disperses and feels.
A well-formulated coated ZO largely sidesteps this issue.
Zinc Oxide is commonly used anywhere from 10% up to the regulatory maximum in sunscreens (25%).
Mineral-only broad-spectrum products often land in the 15-25% range to hit higher SPF and UVA values. Keep in mind SPF performance depends heavily on particle size, dispersion, and the rest of the formula, and not just the percentage.
As an OTC skin protectant like diaper creams, ZO typically runs higher at roughly 10-40%.
This ingredient is generally easy to work with and doesn't photodegrade.
The only thing to know is that uncoated ZO can be a bit reactive in a formula.
Under UV, it can break down sensitive ingredients like other actives or UV filters. This is another reason coated versions are standard. ZO can also react with very acidic ingredients or throw off stability of some creams. A good formula will get around this with the right coatings and dispersion.
The EU's Scientific Committee on Consumer Safety has concluded that ZO nanoparticles "can be considered to not pose any risk of adverse effects in humans after application on healthy, intact or sunburnt skin".
You might hear that ZO is "toxic"; this is because an in-vitro (test tube) study suggested micronized ZO had potential phototoxicity. In vivo (human) investigations have disputed this and the results have come back reassuring.
So does ZO penetrate skin? The short answer is no, not in any way that matters.
The most relevant evidence comes from real-world human studies: in one, volunteers applied ZO nanoparticle sunscreen hourly for six hours and daily for five days. The advanced imaging showed the particles stayed on the surface and never reached the living epidermis, and no cellular toxicity was found.
Other in-vivo and ex-vivo work agree; ZO nanoparticles don't cross the stratum corneum, even on flexed, massaged, or barrier-impaired skin.
A small amount of solubilized zinc ions can dissolve off the particles and enter the upper skin. But the quantities are tiny compared to the zinc already naturally present in your body, and studies haven't found this to cause local toxicity.
The sunscreen bans you've heard of (like Hawaii's) are aimed at two chemical filters, Oxybenzone and Octinoxate. ZO itself it not banned and is often recommended instead.
So far, there's no solid evidence that any form of ZO harms reefs. It is an ongoing and active area of study, and worth keeping an eye on.
If you're traveling somewhere with these rules, a non-nano mineral sunscreen is the safe bet.
Learn more about Zinc Oxide