Nano-Sunscreens: Not Worth the Risk
Friends of the Earth teamed up with Consumers Union and the International Center for Technology Assessment to compile the latest info about nanomaterials in sunscreens (pdf) and their potential hazards. When you look at the data, it’s clear that sunscreens containing nanomaterials are not worth the risk.
Consumers Union tests found no correlation between nanomaterial content and sun protection. Manufactured nanomaterials are widely used in sunscreen to make sun-blocking ingredients like titanium dioxide and zinc oxide rub on clear instead of white. While these nanomaterials don’t improve sun protection, they exhibit different fundamental physical, biological, and chemical properties than their larger counterparts. Very few nanomaterials have been adequately tested, though available data shows their small size makes them more able to enter lungs, pass through cell membranes, and possibly penetrate damaged or sun-burnt skin.
Studies have raised red flags about the environmental impacts that may stem from the release of nanomaterials into broader ecosystems. Once released into the environment, many nanomaterials may persist and accumulate as pollutants in air, soil or water. A 2006 study demonstrated that some forms of titanium dioxide nanoparticles (popular ingredients in nano-sunscreens) are toxic to algae and water fleas, especially after exposure to UV light. Algae and water fleas are a vital part of marine ecosystems.
Further concerns have been raised about risks to workers who produce nano-containing products. Workers handling nanomaterials are likely to be exposed at much higher levels than the general public, and on a more consistent basis. There are currently no established safe levels of exposure to nanomaterials and no reliable systems and equipment to protect workers from harmful levels of exposure.
Consumers need to know that manufactured nanoscale zinc and titanium oxides are not necessarily the most effective or safest choice for effective sun protection. They are also not the only option. Besides several different carbon-based active ingredients, consumers can also look for larger-scale, more opaque metal-oxide based sunscreens (e.g. titanium dioxide or zinc oxide which are ‘inorganic’ and do not contain carbon atoms), although without mandatory labeling these may be very hard to find (at least in the U.S.).