UVA rays range from 320 to 400 nm on the ultraviolet spectrum. The medical community has begun to pay attention to their presence, as they are potentially responsible for skin cancers and definitely responsible for hyperpigmentation, sun spots, redness and wrinkles. Because their effects are longer term, damage testing is not as easy as it is with UVB--with UVA one doesn’t burn, one ages.
Three ingredients commonly used by US sunscreen manufacturers provide protection from the longer UV wave-lengths: Avobenzone, 310-400 nm, Titanium dioxide, 290 to 360 nm, and Zinc oxide, 290-400 nm. Avobenzone degrades after 30 minutes in the sun, so sunscreens including avobenzone as an active ingredient must be applied very frequently if one is to receive adequate protection. Sunscreens with avobenzone stabilized with octocrylene are also available, though octocrylene has been reported to cause contact dermatitis. (Daniel More, MD, About.com Guide, July 9, 2009)
This brings us to the subject of mineral sunscreens, which do indeed protect at the higher end of the UV spectrum. Zinc oxide in particular protects into the 380 to 400 nm range, thus offering the broadest protection of all. This is the reason we have seen an increase in the number of companies offering zinc oxide as the sole active ingredient in their screens. That is the good news.
The bad news is that while more zinc oxide sunscreens are available, virtually all of them contain nanoparticles. Even the sunscreens proclaiming non-nano zinc oxide do contain particles in the 100-200 nm range, which is still very small. The EWG, while giving a thumbs up to nano-sunscreens, does provide this precautionary note: "Mineral formulations incorporate zinc oxide or titanium dioxide in nano- and micro-sized particles that can be toxic if they penetrate the skin. Most studies show that these ingredients do not penetrate through skin to the bloodstream, but research continues."
Fortunately for the consumer, the situation is not as bleak as the EWG paints it. The choice is not between an organic (chemical) sunscreen or an inorganic (mineral) nano-screen. Companies such as Badger and Marie Veronique Organics use non nano zinc oxide in their formulations are aware of the risks presently posed by nanoparticles.
Our recommendation is to go with the companies committed to your safety. They are using the safest and most effective broad spectrum sunscreen agent, zinc oxide, in truly non-nano size forms. It can be done, and your health is too important to settle for second best.
Marie Veronique Nadeau founded Marie Veronique Organics over 10 years ago and is a nationally recognized formulator and beauty expert. She collaborates with her daughter, Jay Nadeau, physicist and bio-medical engineer, to carefully choose each ingredient in her products to address the causes of aging at the source. Marie holds a BS in Math and Chemistry as well as an esthetics license from Paris Beauty College. She is a mother of 2 and a grandmother of one. When she is not developing cutting edge anti-aging products, she can be found reading at her local library or foraging for mushrooms with her granddaughter.
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