Why “Nano” Zinc Particles Are Misunderstood — According to Science

Why “Nano” Zinc Particles Are Misunderstood — According to Science

There’s a lot of talk about what’s healthy vs. not healthy for your body and the environment…

But how much of it is true?

There are products that claim to be “natural” or “healthy”, but they’re not.

And there are products or ingredients that people think aren’t healthy, but when you look at the science, they’re actually fine.

One of the most misunderstood ingredients in the sunscreen market is nano zinc.

Zinc (specifically, Zinc Oxide) is an extremely popular active ingredient in sunscreen, and there’s a fierce debate on whether sunscreens should use nano or non-nano.

Today, we’re going to share WHY the science behind nano Zinc Oxide is surprising.

You’ll learn 3 main things:
  1. What exactly is “nano” Zinc Oxide?
  2. Are there health or safety risks from nanoparticles in sunscreens?
  3. Do nanoparticles give you a better sunscreen?

What are Zinc Oxide Nanoparticles?

To first understand nano Zinc Oxide, you have to understand Zinc Oxide.

Zinc Oxide (ZnO) is an inorganic compound in the form of a white powder. It’s insoluble in water and used for many reasons.

Products like:
  • Baby powder and diaper rash creams
  • Antiseptic ointments
  • Anti-dandruff shampoo
  • White pigment in paint
  • And, of course, sunscreen

Although ZnO occurs naturally as the mineral zincite, ZnO is generally manufactured from zinc ore.

During the manufacturing process it can be produced in a variety of sizes depending on the desired end use…

If ZnO is produced with average particle size above 100nm, it’s considered non-nano.

If ZnO is produced with average particle size below 100nm, it’s considered nano.

In other words, non-nano is greater than 100nm, while nano is less than 100nm.

Are there health or safety risks from Nanoparticles in sunscreen?

There’s a lot of attention about nanoparticles being harmful.

You’ll see a lot of sunscreens advertising “non-nano Zinc” as their active blocking ingredient.

But, it’s not clear where the attention to nanoparticles originated:
  1. There’s no real scientific evidence where the nano fear came from. Someone started the narrative that nano is bad and — despite no scientific evidence — it became common belief.
  2. It’s nearly impossible to make 100% sure that nanoparticles, like Zinc Oxide, are not in a sunscreen. Many companies that advertise non-nano particles have no proof this is actually true! It’s challenging, if not impossible, to make sure a non-nano ingredient is actually fully non-nano.
To go into the science, a report the Australian Department of Health’s Therapeutic Goods Administration (TGA) published in 2016 talks about the safety of nano Zinc Oxide.

The report was titled “Literature Review on the Safety of titanium dioxide and zinc oxide nanoparticles in sunscreens”, and here’s the summary:

“This scientific review report is limited to the review of safety concerns surrounding zinc oxide (ZnO) and titanium dioxide (TiO2) nanoparticles (NPs) present in sunscreens. The two main issues considered in this review are the evidence for the ability of these NPs to penetrate the skin to reach viable cells and the potential toxicity exerted by them.

“The TGA has been continuously monitoring the emerging scientific literature in this area and working cooperatively with international regulatory agencies to ensure that appropriate regulatory action is undertaken if any unacceptable risk of harm/toxicity is identified.
“The majority of in vitro studies (using both animal and human skin) and in vivo studies have shown that both ZnO and TiO2 NPs either do not penetrate or minimally penetrate the stratum corneum and underlying layers of skin. This suggests that systemic absorption, hence toxicity, is highly unlikely.
“In conclusion, on current evidence, neither TiO2 nor ZnO NPs are likely to cause harm when used as ingredients in sunscreens and when sunscreens are used as directed.”

Based on the science, the fear around nano Zinc Oxide may be overblown.

There’s no evidence that there are any health and safety risks posed by nano Zinc particles.

If you can’t tell if your sunscreen is nano or non-nano, from a safety perspective, it shouldn’t matter.

Do Nanoparticles give you a better sunscreen?

In addition to no scientific evidence that nanoparticles are harmful in sunscreen, there’s a HUGE benefit to nano Zinc…

Nano Zinc absorbs, not just reflects, UV light and scatter visible light. This means greater SPF.

But nano particles aren’t perfect…

The slightly larger, non-nano ZnO offers greater UVA protection — which means it’s better at reflecting UVA.

To make the most effective sunscreen, the data shows a combination of nano and non-nano particles in the Zinc is the best combination.

Many natural sunscreen brands that don't want to use chemical reactions to create sun protection, but do want a sunblock that rubs in easily, are intentionally switching to using a blend of nano and non-nano ZnO.

Going completely without nano can cause some issues too:

  1. Some sunscreens use only the larger particle size (non-nano), which is why they are chalky in appearance when applied.
  2. The larger particles reflect visible light and appear white on the skin.
  3. The smaller size of particles increases cosmetic acceptability by users as they are much less visible after application.


A blend of nano and non-nano particles strikes a good balance between performance and aesthetics for the user.

And with scientific evidence showing that nanoparticles are not harmful to your body or the environment, it’s safe if there are nanoparticles in your sunscreen.

Our sunscreen Albedo doesn’t intentionally use nano particles at this time, but our Zinc Oxide ingredient source likely has traces of nanoparticles for full sun-blocking coverage.

Check out Albedo products here. Made for surfers, by surfers we offer 100% natural, water-resistant, SPF 30+ triple-protection sunscreen (and after-surf moisturizer).