Why we use what we use

Non-nano zinc oxide

Zinc oxide is one of only two sunscreen actives the FDA classifies as GRASE — Generally Recognized As Safe and Effective. The other is titanium dioxide. Every other active sold in the U.S. (oxybenzone, avobenzone, octinoxate, octocrylene, homosalate, and the rest) was reclassified in 2019 as needing more safety data.¹

Zinc oxide works by sitting on the surface of the skin and reflecting and absorbing UV radiation across both UVA and UVB ranges. It’s broad-spectrum by default — no other filter required.²

Why zinc oxide and not titanium dioxide?

Both are FDA-approved mineral filters, but they’re not interchangeable. Zinc oxide provides broader UVA coverage — particularly in the long-UVA range (340–400 nm) that drives photoaging and pigmentation. Titanium dioxide drops off faster in that range and is generally paired with another filter to fill the gap.² Zinc is also better tolerated by inflamed and sensitive skin, which matters for our customer base. We use isoamyl laurate (a plant-derived ester from coconut and corn) to disperse the zinc particles evenly so the clear formula rubs in without a white cast.

What “nano” actually means

“Nano” refers to solid particles between 1 and 100 nanometers in size — a nanometer is one billionth of a meter, or 0.001 microns. Non-nano zinc oxide uses particles larger than 100 nm (typically 100–200 nm).³

“But aren’t chemical sunscreens even smaller than nano?”

Yes — and this trips a lot of people up. Chemical filters like oxybenzone and avobenzone are individual molecules, roughly 0.5–1 nm in size. Technically smaller than nanoparticles, but they’re not classified as “nano” because they’re not particles at all. They’re dissolved organic compounds.

The distinction matters because the absorption mechanism is completely different:

• Mineral particles (nano or non-nano): solid; sit on the skin’s surface; reflect and absorb UV physically.
• Chemical filters (small molecules): dissolved in the formula; lipophilic (fat-soluble); cross the skin barrier by dissolving through it, the same way nicotine patches deliver drugs.

So when people say “chemical sunscreens are absorbed into your bloodstream,” they’re not describing nano absorption. They’re describing molecular absorption — a different mechanism entirely.

Does nano zinc oxide get into your bloodstream?

Here’s the honest version, because the marketing on both sides has been misleading.

Multiple peer-reviewed studies on intact, healthy skin have shown that nano zinc oxide particles themselves don’t penetrate beyond the stratum corneum (the outermost dead skin layer). They don’t cross into living tissue.⁴

However — and this is the part most “nano is dangerous” marketing skips — the 2010 Gulson study using isotope tracking found that trace amounts of zinc itself did show up in the bloodstream of people using nano zinc sunscreen. The current scientific interpretation is that the particles dissolve into zinc ions on the skin’s surface, and those ions get absorbed in tiny amounts. This is biologically normal — zinc is an essential mineral your body uses every day.⁵

So is nano zinc safe? Should we just use it?

This is where we have to be honest about what we don’t know. The short-term skin penetration data on nano zinc is reassuring. But:

• Most studies are short-term (days to weeks). Long-term cumulative exposure data is incomplete.⁴
• Studies are run on intact, healthy skin. Sunburned, broken, or compromised skin behaves differently and hasn’t been studied as thoroughly.⁴
• Nano-sized zinc is more bioavailable to marine organisms — coral, plankton, and small invertebrates — than larger particles. Marine ecotoxicity is the strongest established evidence against nano.⁸

So we’re in a similar situation to chemical sunscreens, just with much smaller stakes: there’s uncertainty, and the cost of choosing the more conservative option (non-nano) is essentially zero — it works just as well as a UV filter.

Our position: when there’s no performance trade-off and the more conservative choice has stronger evidence behind it (marine safety, sensitive-skin caution), take the conservative choice. That’s why we use non-nano.

Iron oxides & visible light protection

Here’s something most sunscreen companies don’t talk about: SPF only measures UVB protection. It doesn’t measure UVA, and it definitely doesn’t measure visible light or blue light (HEV) — the wavelengths that come from sun, screens, and indoor lighting.

Visible light is now well-documented as a driver of pigmentation, melasma, and photoaging, particularly in skin types III–VI. A 2010 study in the Journal of Investigative Dermatology showed that visible light induced more sustained pigmentation than UVA1 alone.⁹

Zinc oxide blocks UV but does relatively little against visible light. The ingredients that do block visible light are iron oxides — the pigments that give tinted sunscreens their color. Studies have shown that iron-oxide-tinted sunscreens significantly outperform untinted mineral sunscreens at preventing visible-light-induced pigmentation.¹⁰

Why we avoid chemical UV filters

In 2019 and 2020, the FDA published two studies in JAMA showing that common chemical sunscreen filters — oxybenzone, avobenzone, octocrylene, homosalate, octisalate, and octinoxate — are absorbed into the bloodstream at concentrations exceeding the FDA’s threshold for requiring further safety data. After a single application, plasma concentrations exceeded the threshold; after four days of use, levels were higher still. Some filters were still detectable in the bloodstream weeks after the last application.^6,7

Here’s the honest parallel to nano zinc: just like with nano, we don’t have definitive proof these chemical filters cause harm at the concentrations they reach. The FDA didn’t say they’re dangerous — the FDA said they need more data, and the agency has formally requested it. Until that data exists, our position is the same as it is for nano: when in doubt, choose the option that doesn’t end up in the bloodstream.

Specific concerns by ingredient:

• Oxybenzone — detected in human breast milk, urine, and amniotic fluid; potential endocrine disruptor; banned in Hawaii reef-safe legislation.^11,12
• Octinoxate — banned alongside oxybenzone in Hawaii; documented hormone disruption in animal studies.¹²
• Octocrylene — degrades into benzophenone over time, a possible human carcinogen (IARC Group 2B).¹³

Mineral filters like zinc oxide don’t have this absorption profile. They sit on top of the skin and are not absorbed systemically as intact UV-filter molecules.

Reef-safe isn’t a marketing word — it’s a law

Hawaii’s Act 104, in effect since January 2021, prohibits the sale of sunscreens containing oxybenzone or octinoxate. The law was passed after research showed these ingredients contribute to coral bleaching and reproductive harm in reef ecosystems, even at extremely low concentrations.^12,14

Palau, Bonaire, Aruba, the U.S. Virgin Islands, and parts of Mexico have followed with similar restrictions. Some have expanded the banned list to include octocrylene and certain parabens.

Ginger Armor formulas are free from oxybenzone, octinoxate, octocrylene, and parabens. They meet or exceed every reef-safe standard currently in force.

Squalane (sugarcane-derived)

Squalane is the saturated, shelf-stable form of squalene — a lipid your own skin produces naturally. Up until the 1990s, most commercial squalane was harvested from shark liver oil. Today, the industry standard is plant-derived squalane, most commonly from sugarcane fermentation.¹⁵

We use sugarcane-derived squalane (the same source used by Biossance and other premium skincare brands) for three reasons:

• Biocompatible — molecularly identical to a lipid your skin already makes, so it absorbs without sitting on top or clogging pores.¹⁶
• Non-comedogenic — rated 0–1 on the comedogenic scale, meaning it does not clog pores even on acne-prone skin.¹⁷
• Sustainable — no animals harmed, fully renewable, and no synthetic petroleum derivatives.

Fragrance-free, intentionally

“Fragrance” on a cosmetic label can legally represent dozens or even hundreds of individual chemicals — they’re protected as trade secrets under FDA regulations and don’t have to be itemized.¹⁸ Fragrance is consistently ranked among the top three causes of contact dermatitis in cosmetic products by the North American Contact Dermatitis Group.

For people with rosacea, eczema, or sensitive skin, there’s no reason to introduce that risk. Ginger Armor formulas have no added fragrance — what you smell is the natural, faint scent of the ingredients themselves.