From time to time concerns are raised about the use of nanoparticles in sunscreen and whether or not sunscreen is harmful.

To date, there has been no evidence to suggest sunscreen has a negative impact on our health. However, as we are always encouraging our patients to apply sunscreen daily, I wanted to take some time to unpack this issue and help lay any concerns you might have to rest.

What are nanoparticles?

Nanoparticles are tiny particles measuring less than 0.0001mm. They can occur naturally in things like dust, sand, waterways and even viruses; and are also used in manufacturing to make products more appealing to consumers.

Some of the commercial applications making use of nanoparticles include:

  • Whitening agents used in products like toothpaste
  • Scratch-proof reading glasses
  • Anti-graffiti coating for walls
  • Stain-resistant fabrics
  • Preventing the growth of bacteria in socks; and
  • Helping car tyres better adhere to the road.

Why are nanoparticles in my sunscreen?

Early sunscreens were much thicker than they are today and would often leave a chalky white residue on the skin. Nanoparticles were introduced to sunscreens to make them lighter and more comfortable to wear, as well as invisible once applied.

Why are people worried about nanoparticles?

Some studies have reported that nanoparticles may be absorbed through the skin and into the body.

One study on mice found nanoparticles effected good bacteria in the gut, when added to the mice’s drinking water. However, this study exposed the mice to a very large, daily dose of nanoparticles – up to 50 times the amount a human would typically encounter in food additives and, without food, the nanoparticles had nothing to bind to.

The concern around nanoparticles in sunscreen seems to stem from the nanoparticles in some sunscreens causing premature weathering to Colorbond roofing sheets, car paints and other consumer products.

Should I be worried about nanoparticles in my sunscreen?

Studies have failed to find any evidence that nanoparticles cause damage to human cells. In fact, one study has shown that when sunscreen’s nanoparticles are absorbed by the skin, our immune system naturally attracts and discards them before they reach the blood stream.

So should I keep applying sunscreen?

We say “definitely!”

Australia is home to the highest rate of skin cancer deaths in the world, and 2 out of 3 Australians will be diagnosed with some form of skin cancer. However daily use of sunscreen (not just when you’re at the beach) is proven to significantly reduce your risk of developing skin cancer.

We firmly believe that it’s much better to wear sunscreen and protect against a high risk of skin cancer than to not wear sunscreen and protect against an unfounded risk of exposure to nanoparticles.

Read more about optimal sunscreen application here.