Do Sunscreen's Cause Cancer - Fact or Fiction? Part 2


In light of the many media articles alleging that sunscreen agents cause cancer, I reviewed the facts on some of those ingredients in my last post. Today I’ll give you the facts on other sunscreen agents subjected to unsubstantiated cancer causing claims.

Octinoxate, also known as methoxycinnamate or ethylhexyl methoxycinnamate, is the traditional and most commonly used sunscreen active with a substantial safety record. Regretfully, this tried, and true basic sunscreen agent has also been subjected to unsubstantiated claims that it causes cancer, which has prompted many consumers to be suspicious of their sunscreens. In reality, there hasn’t been a single study proving that octinoxate SPF products either cause or increase the risk of developing cancer. The only studies making these unfounded claims are those ignorant of how skin care products with sunscreen ingredients are used and formulated. For example, some studies applied unusually high concentrations of octinoxate directly to the skin or fed high concentrations to lab animals. So, the bottom line is, octinoxate is safe as long as you don’t eat or drink it.

Furthermore, there isn’t a single existing study that substantiates the claim that octinoxate causes cancer or any other illness when used in sunscreen formulations.

Nanotechnology has been successfully used to develop products from pharmaceuticals to skin care. It indicates an array of particle sizes that can range anywhere between 1 to 100 nanometers.

If you’re wondering whether or not nanoparticle sunscreen ingredients, such as titanium dioxide & zinc oxide, can penetrate the skin and enter the bloodstream, it's essential to get the facts straight.

To maintain their efficacy as sunscreen actives, titanium dioxide and zinc oxide, are at the high end of the nanometer scale (around 100 nanometers). They are also polymer-coated to guarantee they stay on the skin’s surface and therefore protect it from overexposure to the sun.

In their 2010 case study of nano-scale titanium dioxide in sunscreen formulations, the Environmental Protection Agency reported that there is no health issue related to its use. Their study also affirmed that nano-sized titanium dioxide did not penetrate below the top layer of human skin.

Dermatologists from the Memorial Sloan-Kettering Cancer Center studied nanoparticle titanium dioxide and zinc oxide and confirmed that "It has been established that the stratum corneum is an effective barrier preventing the entry of nano-ZnO (zinc oxide) and -TiO2 (titanium dioxide) into deeper layers of the skin. These results were published in the April 2011 edition of Photodermatology, Photoimmunology & Photomedicine. 

Recently there have been claims that zinc oxide can increase the risk of cancer. Again, these claims are unsubstantiated. The existence of a health threat from nano-sized titanium dioxide or zinc oxide is baseless.

International medical and scientific research on sunscreen safety is on-going, and comprehensive. It has also proven that sunscreens remain safe to use. Conversely, unprotected sun exposure is the true danger that increases the risk of cancer, not to mention that it also causes premature aging. 

In addition to the proper daily use of your SPF 30 +, you should also wear sunglasses, a hat, and sun-protective clothing. If possible try to limit your sun exposure, and don’t forget to reapply your sunscreen often.

Sources: British Journal of Dermatology, 160:80-91, January 2009Environmental Health Perspectives, July 2008, page 116; Journal of the American Medical Association, 306:302-303, July 2011; Photodermatology, Photoimmunology & Photomedicine, 27:58–67, April 2011U.S. Environmental Protection Agency, Nanomaterial Case Study, November 2011.


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