What's in your sunscreen?

Have you ever considered what's in your sunscreen? Australians are all very aware of the risks of sun cancer, with sunscreen part of our every day life. But do we really understand what the differences are between natural and chemical sunscreen?

In short there are two types of sunscreen available: chemical and natural.

• Chemical sunscreens are designed to absorb ultraviolet (UV) rays, these sunscreens absorb into the skin and are made with nanoparticles.
• Natural sunscreens use the active ingredient zinc oxide to form a barrier between the skin and the sun and are not absorbed into the skin, rather they sit as a layer on top for protection.

What are Nanoparticles anyway?

Nanoparticles are basically very small particles of metal oxide which are invisible to the skin. They are manufactured smaller versions of chemicals like zinc oxide or titanium dioxide. These sunscreens are used widely, especially as they are invisible and often considered more attractive than the white zinc nose! 

Zinc oxide and titanium dioxide have been used in sunscreens for many years, but as larger particles. Now that they have been reduced to 'nanoparticles' this is where the concerns arise. As it has been suggested that the smaller particles are able to be absorbed through the skin. These nanoparticles produce 'free radicals' which are linked with the formation of cancer.                          

                                                                                               

There are other chemicals contained in your sunscreen that can cause adverse reactions as well.

• Oxybenzone, is an endocrine hormone disruptor and is absorbed through the skin. This, it has to be said, is being phased out by manufacturers, however, it is well worth checking the label. 
• Parabens are a group of chemicals that are used as a preservative. They are considered to be hormone disruptors as well, which interfere with how hormones function in the body.

Now, the jury is out on whether 'free radicals' are produced, or even if sunscreens with nanoparticles are absorbed into the skin. But I firmly believe that any suggestion that a product may be linked with cancer, alter hormonal function or be absorbed into our bodies with adverse effects has to be treated with some scepticism. 

Studies are inconclusive but they are ongoing, so expect to hear more about this very important issue in the coming years! 

Image courtesy of Sam Spratt on Flickr.