When it comes to your particle size, size DOES matter! In preparation for my Sunscreen Safety Live Facebook social next week I want to touch on a word that you will see often when talking about safer sunscreens and that is particle size, nano vs. non-nano.
The two most common safer ingredients that block the sun’s rays are titanium dioxide and zinc oxide. They are free of all the harmful side effects that an ingredient like oxybenzone has. Zinc oxide tends to the ingredient of choice, but it oftentimes forms a white residue on the skin. You have all seen someone that lathered themselves up in zinc oxide, they look like Casper the ghost.
This is where particle size comes into play. The smaller the particle size, called nanoparticle, the less likely it is to cause a white residue. The larger the size, the more likely it causes a white residue, but it is more effective at protecting you from the sun. The negative aspect of the smaller particle size is that it potentially can penetrate the skin and get into the blood stream. The larger particle size sits on top of the skin. Another concern is that the smaller nanoparticles can cause damage if inhaled. The Environmental Working Group recommends that you avoid any spray sunscreen with titanium dioxide or zinc oxide regardless of particle size
Beautycounter uses a non-nano zinc oxide as it’s main sunscreen ingredient. There is some question about what this term really means and due to variability between manufacturers this term is inconsistent from company to company. There simply isn’t enough research to know what impact the particle size really has, but we aren’t willing to take the risk. And, while we use a non-nano zinc oxide it blends in beautifully with no white streaks.