The zinc we are using is exceptional. It is made up of primary nano (very small) particles in the tens of nanometers range. These small particles form aggregates (clusters of nanoparticles with very strong bonds) that make up a nano porous structure with a secondary particle a few microns to tens of microns in size. Larger aggregates have a unique porous structure that provides a closer match between the refractive index of the particle and the refractive index of the emollient, resulting in high transparency.
The unique aggregated porous structure provides both high UVB SPF and UVA protection.
Many sunscreens claim to be “non-nano”. EWG- Environmental Working Group in the USA, a respected independent NGO that does a lot of sunscreen testing had this to say:
“A number of companies sell products advertised as containing “non-nano” titanium dioxide and zinc oxide. These claims are generally misleading. While particle sizes vary among manufacturers, nearly all would be considered nanomaterials under a broad definition of the term, including the definition proposed in 2011 by the federal Food and Drug Administration (FDA 2011b).”
Nano is a very big topic around very small particles.
Several well respected organisations around the world have conducted rigorous reviews of all the science available to date on nano zinc oxide: The EU Scientific Committee on Consumer Safety, the Australian TGA and USA’s Environmental Working Group.
The EU SCCS indicated that
“there is no evidence for the absorption of zinc oxide nanoparticles through skin and via the oral route. In the Margin of Safety calculation, the calculation of the exposure to zinc oxide nanoparticles results in acceptable Margin of Safety for both the oral and dermal routes. The SCCS later confirmed that zinc oxide nano may be used in cosmetic products other than sunscreens, intended for dermal application.”
We were concerned enough by the debate to not just rest on the laurels of these 3 organisations, but have done our own research into the available studies and data. We hold on file copies of many of the studies. We have essentially come to the same conclusion.
While there are no absolutes, with the balance of UV and environmental factors, as well as the research coming through on chemical and badly balanced UVA/UVB sunscreens, we are grateful for Sun Balm and trust in its safety and efficacy.