Tuesday, May 27, 2014

Are Nanoparticles Safe in Sunscreen?

Nanotechnology in sunscreens has received a buzz of attention with the consumer conscious wondering about the dangers outweighing the benefits.

Nanoparticles or Micronized particles
Nanoparticles


What Is a Nanoparticle

Nanoparticles in sunscreen in short is taking the mineral active ingredients in sunscreen and making their particle size extremely small, measuring about 1 / 8,000th the size of a human hair. Nanoparticles are found naturally and recently have been manufactured in many applications, one being in sunscreen to allow the application to go on clear and lightweight, without a white film over the skin.

What Are the Danger's of Nanoparticles in Sunscreen?

Titanium Dioxide, and to a smaller extent Zinc Oxide are photocatalysts.  This means that UV rays can cause them to cause free radical damage in live skin cells.  The smaller the particle, or nanoparticle, the more the UV rays will cause this reaction, and the more opportunity it has to penetrate deep into the skin where their is live skin cells.  The smaller the particle also, the less effective it is with UVA rays, the type of ray that is prevelant all year around, all day.

Titanium Dioxide is used in many foods to give a white fresh look including ice cream, toothpaste, and the ever popular M&M's candy.  Nanoparticles in many ingredients are dangerous if inhaled as it is harder to remove from the lungs, making powder sunscreens more dangerous.

Are the Danger's Valid?

Research hasn't been able to determine if the nanoparticles reach live cells to cause damage.  Humans in a 5 day study showed a negligible amount of zinc oxide in the blood stream. (Gulson 2010)  To counteract the free radical damage, coatings such as silica and or alumina are put on the particles which result in the UV reaction to be encapsulated and not harmful by 99% effectiveness. (SCCNFP 2000, Pan 2009)  Careful precautions are also put into making the active ingredients stable to reduce this reaction.  The FDA lately has issued a draft guidance in looking further into the issue to decide the dangers.



How to Shop for Sunscreen Safely

Benefits for using sunscreen far outweigh the damaging effects of the free radical damage.  With special coatings on the particles, their may not be a reason for concern at all.  And the jury still is out on whether the sunscreen penetrates to live skin cells.  Using Vitamin C Serum daily in the morning will help free radical damage and counteract the effects of damage from UV rays caused naturally or with sunscreen.  Using sunscreen with antioxidants also help to mitigate free radical damage.  Non-Nano labelled on products can be misleading as their is not a regulation on size, and some particle sizes may be still at a nano level.  Many propose labeling to say whether it's nano or not to make an informed decision.  Simply, the thicker the sunscreen looks and feels, the less of a nano form it will be.


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