Nano vs Non-nano particles in natural zinc-based sunscreen - what's the difference?

Nano vs Non-nano particles in natural zinc-based sunscreen - what's the difference?


Zinc is an ingredient in the majority of natural sunscreens because it provides sun-screening action by absorbing or reflecting harmful UV rays away from your skin. This is how mineral sunscreens work - by creating a physical layer of particles on your skin that refract the sunlight, protecting you from damage.

In contrast, generic sunscreens use a chemical reaction to dissipate the sun's rays away from your skin. This is why mineral sunscreens are instantly effective, and generic sunscreens take up to half an hour to work. More importantly, it is known that many of the chemicals and fillers used in generic sunscreens are potentially harmful, including skin irritants, hormone disruptors, allergens and even some which can cause skin cancer

So, natural sunscreen is good, and natural sunscreens generally contain zinc.

Is zinc safe to put on our skin? 

Yes, zinc is a natural, safe sun barrier suitable even for young children's skin. The zinc particles clump together in the sunscreen but retain their transparent properties when on the skin. And compared to other UV filters, zinc particles are more stable and last longer on the skin; and are low irritant and low allergen.

Does Frankie Apothecary use nano or non-nano zinc?

The zinc in our sunscreen is 'Non-Nano' or micronised, meaning that the minimum particle size is above 0.1um. 

Nano and Non-Nano refer to the size of the zinc oxide particles used in a sunscreen. An inconceivably tiny Nano-particle measures between one and 100-billionths of a meter... that means you can fit thousands of them across a human hair. The slightly larger but still utterly microscopic Non-nano particles are bigger than 100-billionth of a meter, like what we use in Frankie's natural sunscreen.

However, the EU and Australia define a product as being 'nano' in different ways; there is no governing body able to certify a product as non-nano; and even if you aim to have a non-nano product like ours, it is to all intents and purposes impossible to completely exclude all nano particles - or if you could, to prove that you have done so.

The benefit of nano-zinc is that the particles absorb UV light and scatter visible light, providing greater SPF - while slightly larger Non-nano particles offer greater UVA protection - so the combination delivers a high SPF rating along with UVA protection. Many natural sunscreen brands that don't want to use chemical reactions to create sun protection, but do want a sunscreen that rubs in easily, are intentionally switching to using a blend of nano and non-nano zinc.

If any nano-particles of zinc appear in Frankie sunscreen, are they safe?

Research by very reputable organisations around the world is unanimous in showing no penetration of the skin by nano-particles of zinc oxide. The verdict is that even zinc oxide nano-particles will not - cannot - penetrate our skin to get into our bloodstream.

The EU's Scientific Committee on Consumer Safety concluded: ...the nanoparticles of zinc oxide do not get into the body through the skin. ... no health impact of the ‘nano’ nature of zinc oxide is expected.

Germany's Federal Institute for Risk Assessment, the Bundesinstitut für Risikobewertung, concludes: ...the behaviour of nanoparticles made of zinc oxide on the skin has been well examined. It was confirmed in several experiments that these nanoparticles cannot penetrate healthy human skin cells and remain on the skin surface.

Likewise the Australian Government's Department of Health concluded that: Zinc Oxide nano-particles are not likely to cause harm when used as ingredients in sunscreens and when sunscreens are used as directed. They continued to say that because the minerals will aggregate or cluster into bigger lumps on the skin that penetration is even more unlikely.

We are all about gentle, natural skin care and protection

Knowing what goes on our skin is super-important to us - as you can probably guess by our range of all natural skin care and ezcema care products. Frankie began from a mother's drive to find skin-soothing natural options for a little girl with heartbreaking eczema. Frankie Apothecary's all natural sunscreen was the second product developed (after our gorgeous eczema-soothing Kawakawa Balm!) as sunscreens often irritate sensitive skin.

Wherever possible we err on the side of caution, which is why we opted for Non-nano zinc in our natural sunscreen - but we are also confident that any tiny percentage of nano particles that may be included are also safe for us all.

You can shop Frankie Apothecary all natural sunblock online now.




Clare Jaap
Clare Jaap

Hi. I am looking for an eco friendly sunscreen, and read that zinc oxide and titanium dioxide are harmful to sea life. What are your thoughts on that?
Thank you.


does your sunscreen dry “clear” without a white cast

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