What's inside
What's inside
Key Ingredients
Benefits
Concerns
Ingredients Side-by-side
Water
Skin ConditioningZinc Oxide
Cosmetic ColorantCyclohexasiloxane
EmollientButyloctyl Salicylate
Skin ConditioningPropanediol
SolventDicaprylyl Carbonate
EmollientPropylheptyl Caprylate
EmollientDisiloxane
Skin ConditioningPentylene Glycol
Skin ConditioningTrimethylsiloxysilicate
EmollientLauryl Polyglyceryl-3 Polydimethylsiloxyethyl Dimethicone
Skin Conditioning1,2-Hexanediol
Skin ConditioningArgania Spinosa Kernel Oil
EmollientPersea Gratissima Oil
Skin ConditioningCalendula Officinalis Flower Oil
MaskingCeramide NP
Skin ConditioningDisteardimonium Hectorite
StabilisingMagnesium Sulfate
Polyglyceryl-2 Dipolyhydroxystearate
Skin ConditioningIsododecane
EmollientTriethoxycaprylylsilane
Acrylates/Polytrimethylsiloxymethacrylate Copolymer
Skin ConditioningPolyhydroxystearic Acid
EmulsifyingHydroxyacetophenone
AntioxidantDimethicone
EmollientPolyglyceryl-4 Diisostearate/Polyhydroxystearate/Sebacate
EmulsifyingLecithin
EmollientEthyl Palmitate
EmollientIsostearic Acid
CleansingIsopropyl Myristate
EmollientDipotassium Glycyrrhizate
HumectantPolyglyceryl-3 Polyricinoleate
EmulsifyingTocopherol
AntioxidantDipropylene Glycol
HumectantCholeth-24
EmulsifyingHydrogenated Lecithin
EmulsifyingWater, Zinc Oxide, Cyclohexasiloxane, Butyloctyl Salicylate, Propanediol, Dicaprylyl Carbonate, Propylheptyl Caprylate, Disiloxane, Pentylene Glycol, Trimethylsiloxysilicate, Lauryl Polyglyceryl-3 Polydimethylsiloxyethyl Dimethicone, 1,2-Hexanediol, Argania Spinosa Kernel Oil, Persea Gratissima Oil, Calendula Officinalis Flower Oil, Ceramide NP, Disteardimonium Hectorite, Magnesium Sulfate, Polyglyceryl-2 Dipolyhydroxystearate, Isododecane, Triethoxycaprylylsilane, Acrylates/Polytrimethylsiloxymethacrylate Copolymer, Polyhydroxystearic Acid, Hydroxyacetophenone, Dimethicone, Polyglyceryl-4 Diisostearate/Polyhydroxystearate/Sebacate, Lecithin, Ethyl Palmitate, Isostearic Acid, Isopropyl Myristate, Dipotassium Glycyrrhizate, Polyglyceryl-3 Polyricinoleate, Tocopherol, Dipropylene Glycol, Choleth-24, Hydrogenated Lecithin
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
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
We don't have a description for Acrylates/Polytrimethylsiloxymethacrylate Copolymer yet.
Ceramide NP (formerly known as Ceramide 3) is one of the skin's naturally occurring lipids.
Since ceramides are the major lipid components of the skin, they are crucial for maintaining skin barrier and hydration. Ceramide NP most closely mirrors the dominant kind in human skin amongst ceramide subtypes.
This ceramide works by slotting into gaps within the stratum corneum's lipid matrix to limit trans-epidermal water loss (TEWL) and shield the skin against external irritants.
A study with 312 patients found that using a ceramide-containing routine for 4 weeks reduced the severity of atopic dermatitis by over 61%.
Another clinical study in subjects aged 60 and older found that a ceramide body wash and moisturizer improved skin dryness and itchy skin in 15 days.
Overall, ceramides are considered non-irritating and safety tests have found little to no observable adverse effects from using this ingredient.
Ceramide NP is usually sourced from plants (like soybean or rice bran), or produced synthetically.
Learn more about Ceramide NPDicaprylyl Carbonate comes from carbonic acid and caprylyl alcohol, a fatty alcohol. It is an emollient and gives skin a velvet feel. The sources of Dicaprylyl Carbonate may be synthetic or from animals.
As an emollient, Dicaprylyl Carbonate creates a film on the skin. This film traps moisture in, keeping your skin soft and hydrated.
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 GlycyrrhizateDipropylene Glycol is a synthetically created humectant, stabilizer, and solvent.
This ingredient helps:
Dipropylene glycol is technically an alcohol, but it belongs to the glycol family (often considered part of the ‘good’ alcohols). This means it is hydrating and gentle on skin unlike drying solvent alcohols like denatured alcohol.
As a masking agent, Dipropylene Glycol can be used to cover the smell of other ingredients. However, it does not have a scent.
Studies show Dipropylene Glycol is considered safe to use in skincare.
Learn more about Dipropylene GlycolDisiloxane is a type of silicone.
Disteardimonium 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 HectoriteHydrogenated 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 antioxidant with skin conditioning and soothing properties. It also boosts the efficiency of preservatives.
Though naturally occuring in Norwegian spruce needles, this ingredient is usually synthetically created.
This ingredient is not irritating or sensitizing. Recent research also suggests it may have skin-brightening effects through tyrosinase inhibition.
Learn more about HydroxyacetophenoneIsododecane 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 AcidLauryl Polyglyceryl-3 Polydimethylsiloxyethyl Dimethicone is a type of silicone.
Lecithin is a term for a group of substances found in the cell membranes of plants, animals, and humans. They are made up of phospholipids.
Thanks to its amphiphilic structure (water-loving head and oil-loving tail), it is a true multitasker:
It plays well with most ingredients and is typically used at 0.1-1%. However, concentrations up to 50% have been reported in moisturizers.
Learn more about LecithinMagnesium Sulfate is a salt. More specifically, it is an epsom salt, or the bath salt used to help relieve muscle aches.
Despite having ‘sulfate’ in the name, it isn’t a surfactant or cleansing agent like sodium lauryl sulfate. Unlike those sulfates, magnesium sulfate doesn’t have the same cleansing or foaming properties (it's simply a type of salt).
In cosmetics, Magnesium Sulfate is used to thicken a product or help dilute other solids. It is a non-reactive and non-irritating ingredient.
One study shows magnesium deficiency may lead to inflammation of the skin. Applying magnesium topically may help reduce inflammation.
You can find this ingredient in sea water or mineral deposits.
Learn more about Magnesium SulfatePentylene glycol is typically used within a product to thicken it. It also adds a smooth, soft, and moisturizing feel to the product. It is naturally found in plants such as sugar beets.
The hydrophilic trait of Pentylene Glycol makes it a humectant. As a humectant, Pentylene Glycol helps draw moisture from the air to your skin. This can help keep your skin hydrated.
This property also makes Pentylene Glycol a great texture enhancer. It can also help thicken or stabilize a product.
Pentylene Glycol also acts as a mild preservative and helps to keep a product microbe-free.
Some people may experience mild eye and skin irritation from Pentylene Glycol. We always recommend speaking with a professional about using this ingredient in your routine.
Pentylene Glycol has a low molecular weight and is part of the 1,2-glycol family.
Learn more about Pentylene GlycolPolyglyceryl-2 Dipolyhydroxystearate isn't fungal acne safe.
Polyglyceryl-3 Polyricinoleate is a plant-derived emulsifier made by combining glycerin and ricinoleic acid.
It works well for giving buttery lip balms and low-viscosity water-in-oil emulsions a non-greasy and pleasant skin feel.
Typical concentrations range from 0.1-3%.
This ingredient is mild and non-irritating in nature.
Because it is derived from ricinoleic acid, this ingredient may not be fungal acne safe. Ricinoleic acid is an unsaturated fatty acid that the Malassezia yeast can metabolize.
Learn more about Polyglyceryl-3 PolyricinoleateThis ingredient is a water-in-oil emulsifier and is sometimes known by its trade name, Isolan GPS. It helps create stable emulsions by bridging oil and water phases without adding a greasy feel.
Common usage levels sit between 2-5% for this ingredient.
Polyhydroxystearic 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 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 TrimethylsiloxysilicateWater. 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 (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