Featured Question

“There have been articles questioning the safety of micronized ingredients in sun screen. The ingredients are so small they pass much more easily into the body. Could you please tell me what UV Natural USA findings are about micronized zinc oxide?”

Dr. Lanphier's Answer

Thanks for this very important question.  Definitely the record needs to be set straight.  In order to make sure that we give out correct and factual information, I contacted Dr. Tony Kovacs, President of UV Natural USA to give us the scientific facts surrounding Titanium Dioxide and Zinc Oxide.

Dr. Tony Kovacs, President of UV Natural USA, Inc. responds:

Recently there has been a flood of enquiries regarding the topic of nano-particles, specifically targeting Titanium and Zinc as the leading sunscreen ingredients involved in this technology.

We have scoured the documents available on this matter and have made the following findings:

1. The two ingredients, Titanium Dioxide and Zinc Oxide are often collectively referred to in the heading, introduction and summary of the various articles yet the damming data regarding toxicity in the main body of the document refers to Titanium and not Zinc Oxide.  They seem to be referred to collectively as they are both prominent sunscreen ingredients, yet they behave differently as nano-particles.
2. The various “tidbits” of information on the internet seem to loop amongst each other referring to the same body of articles and then using each other’s sites as sources of reference.  In essence the same thing is being said, without any new information, just more people are quoting each other from the same document.
3. Titanium Dioxide is toxic at the macro and nano level whereas Zinc oxide is not. Zinc is in fact required by the cell for a number of essential functions and the cell would die rapidly without it.
4. Titanium Dioxide, coated or uncoated is photoreactive, coated Zinc oxide is not.
5. Titanium Dioxide is not a true physical sunscreen, it absorbs 70% of UV light and only reflects 30% whereas coated Zinc Oxide reflect much closer to the 100% range and is a true physical sunscreen.
6. Coated Zinc Oxide is NOT photoreactive and therefore does not product hydroxyl ions (free radicals in question) whereas uncoated Zinc oxide and Titanium Dioxide, coated or uncoated do.
7. UV Natural uses coated Zinc oxide. The zinc we use is not coated with dimethicone (common) or opt-sol.  It is not photoreactive. We have a patent on the formulation mixture but we can tell you that it is stable so no free radicals are produced.  We do not use any aqueous ingredients therefore we do not need to use the “regular” coatings that the other brands of sunscreen require.
8. UV Natural chose its ingredient list very carefully and we avoided the common sunscreen ingredients due to their toxicity. 

UV Natural continues to research and develop new products with a constant vigil of using safe ingredients. We maintain an awareness of current research and data on toxicity issues and develop our products in line with information available at the time.

“Until recently, microfine inorganic filters seemed to be ideal ingredients to provide broad-spectrum UV protection and to maintain photostability of sunscreens (Anderson et al, 1997;Mitchnick et al, 1999). Dunford et al (1997), however, showed that microfine ZnO and TiO2 not only scattered and reflected but effectively absorbed UV radiation thus initiating ROS formation and catalyzing DNA damage. For uncoated ZnO and for both, the coated and uncoated TiO2Mitchnick et al (1999) measured a significant photocatalytic potential (ZnO < < TiO2), whereas the photoreactivity of coated microfine ZnO appeared to be negligible. As long as relevant transepidermal penetration of microparticles cannot be excluded definitely (Lademann et al, 1999) the photocatalytic potential of inorganic sunscreen ingredients is of importance and should be further investigated (IARC, 2000b).”

Journal of Investigative Dermatology (2001) 117, 256–262; doi:10.1046/j.0022-202x.2001.01425.x
Change of Ultraviolet Absorbance of Sunscreens by Exposure to Solar-Simulated Radiation
Harald Maier, Günther Schauberger*, Konrad Brunnhofer† and Herbert Hönigsmann

1 Division of Special and Environmental Dermatology, University of Vienna Medical School, Vienna, Austria
2 *Institute of Medical Physics and Biostatistics, University of Veterinary Medicine Vienna, Vienna, Austria
3 †Austrian Consumers' Association, Vienna, Austria

Correspondence: Dr Harald Maier, Division of Special and Environmental Dermatology, University of Vienna Medical School, Währinger Gürtel 18–20, A-1090 Vienna, Austria
Received 16 May 2000; Revised 23 January 2001; Accepted 2 April 2001.
http://www.nature.com/jid/journal/v117/n2/full/5601151a.html.

Take Care & Be Well,
Dr. Loretta Lanphier