TGA fact sheet: Sunscreens
Australia has the highest rate of skin cancer in the world. The use of sunscreen is an important preventative measure to help reduce the risk of developing skin cancer and premature skin ageing.
Zinc oxide and titanium dioxide are two of a number of ingredients with proven ability to protect skin from damage due to ultraviolet radiation. Zinc oxide and titanium dioxide are particularly valuable because of their ability to filter UVA as well as UVB light, giving broad protection from damaging sunlight.
Historically, when used in sunscreens, zinc oxide and titanium dioxide are visible, giving the skin a white colour. This effect can be reduced when these chemicals are used in nanoparticle form, where they cannot be seen on the skin but still retain the sun-screening properties of the coarser material.
Recently, there have been questions raised about the safety of sunscreens that contain nanoparticles. Concerns relate to the theoretical possibility that if nanoparticles were to be absorbed into skin cells, they could possibly interact with sunlight to increase the risk of damage to these cells.
In early 2009, the Therapeutic Goods Administration (TGA) conducted an updated review of the scientific literature in relation to the use of nanoparticulate zinc oxide and titanium dioxide in sunscreens.
The TGA review concluded that:
- The potential for titanium dioxide and zinc oxide nanoparticles in sunscreens to cause adverse effects depends primarily upon the ability of the nanoparticles to reach viable skin cells; and
- To date, the current weight of evidence suggests that titanium dioxide and zinc oxide nanoparticles do not reach viable skin cells; rather, they remain on the surface of the skin and in the outer layer of the skin that is composed of non-viable cells.
The TGA is continuing to monitor the emerging scientific literature to ensure appropriate action is taken should any tangible safety concerns be identified.
Given the outcome of the recent review of the scientific literature, the TGA does not require any specific warnings about nanoparticles to be placed on labels of sunscreens.
In Australia, all active ingredients, such as zinc oxide and titanium dioxide, must be declared on sunscreen labels, to help consumers make informed choices. However, it is not a requirement for sunscreen labels to declare the particle size of the active ingredients.
As at July 2009, there were 985 sunscreen products on the Australian Register of Therapeutic Goods (ARTG). There are more than 30 active ingredients approved by the TGA for use in sunscreens in Australia, with most sunscreens containing a combination of different sunscreen agents.
Consumers can obtain further information about sunscreens from the ARTG database <http://www.tga.gov.au/docs/html/artg.htm>.