Sun safety is an important issue in Australia and concerns about sun exposure have led to the development of a booming sunscreen industry, with many brands and various strengths available on the market today. But are commercial sunscreens the answer? The stats are staggering; two in three Australians will be diagnosed with skin cancer before age 70 and 81% of all new cases of cancer in Australia are skin cancer! The primary cause of skin cancer is over-exposure to Ultraviolet (UV) radiation from sunlight. To combat this Australians have been told to ‘Slip, Slop, Slap’ for more than 30 years with the Cancer Council driving the message home that everyone should apply an SPF 15+ sunscreen daily.
SPF Rating and How it is Regulated
SPF rating is determined by a combination of how much UVA and UVB radiation is blocked and how adhesive or waterproof the sunscreen is to your skin. An SPF of 15 means that only 1/15th of the UV radiation will reach your skin within a time period compared to not wearing any sunscreen. The higher the SPF rating, the less damaging rays can reach your skin. In Australia the Therapeutic Goods Administration (TGA) regulates claims of SPF ratings.
Active Ingredients and Nanoparticles
The active ingredients in sunscreen are zinc oxide and titanium dioxide which are naturally occurring minerals that have been used in sunscreen for thousands of years. These mineral oxides reflect, absorb and scatter UVA and UVB rays away from the skin but are visible and give the skin a lighter or white appearance. Now many commercially produced sunscreens are being made with ultra-fine nanoparticles to increase the appeal of sunscreen by reducing the lightening effects. While toxicity of zinc and titanium oxides in their naturally occurring forms and size are unlikely to occur, nanoparticles pose a threat to humans and aquatic life, as the tiny size of the nanoparticles are able to enter the lining of the lungs, and pass through cell walls. Once inside your cells, nanoparticles of zinc and titanium can cause photo-oxidative stress and damage. Repeatedly studies have shown that naturally occurring particle sizes of these minerals do not leach into the body when applied to the skin. If you still have concerns about using these minerals or want to know more about nanoparticles, check out this comprehensive study on titanium dioxide..
Other ingredients commonly found in commercial sunscreens that consumers increasingly want to avoid include sulphite preservatives and chemical absorbers of UV rays like oxybenzone. A great alternative to using commercial sunscreen is to make it yourself!
DIY Natural Mineral Sunscreen Recipe
6 teaspoons (24g) Coconut Oil
6 teaspoons (36g) Vegetable Glycerine
2 teaspoons (6g) Titanium Dioxide
2 teaspoons (6g) Zinc Oxide
Measure out dry ingredients into a small mixing bowl and add the glycerine one teaspoon at a time while stirring until evenly combined. Titanium and zinc have a tendency to clump, so mix well. Add the coconut oil to the mixture and combine. This will make a thin sunscreen with lotion consistency. In hotter regions of Australia, coconut oil will be liquid most of the year and a thicker formula may be needed. For a thicker sunscreen with better durability, replace the coconut oil for shea butter. All of these ingredients are available at Green Living Australia (online and instore).
– Angie Pearson, BHlthSci, GradDipPubHlth, MPubHlth (Ongoing)
 Australian Institute of Health and Welfare (2004). Cancer in Australia 2001. Canberra, Australia: Australian Institute of Health and Welfare, Australasian Association of Cancer Registries.
 Shaath, Nadim A., ed. (2005). Sunscreens: Regulations and Commercial Development. Third Edition. Boca Raton, FL: Taylor & Francis Group.
 Sadrieh, N., Wokovich A. M., Gopee, N. V., Zheng, J., Haines, D., Parmiter, D., Siitonen, P. H., Cozart, C. R., Patri, A. K., McNeil, S. E., Howard, P. C., Doub, W. H., and Buhse, L. F. (2010) Lack of Significant Dermal Penetration of Titanium Dioxide (TiO2) from Sunscreen Formulations containing Nano- and Sub-Micron-Size TiO2 Particles. Toxicological Sciences 115 (1): 156-166.
 Skocaj, M., Filipic, M., Petkovic, J., and Novak, S. (2011) Titanium dioxide in our everyday life; is it safe? Radiology and Oncology 45(4): 227–247.