Sun Screens and which ones to use on babies skin

In Brief

Zinc oxide in a powdered mineral that works as a sunscreen by sitting on top of the skin scattering and absorbing ultraviolet rays.

Zinc oxide is the safest most effective single active sunscreen ingredient. It protects from UVA and UVB rays and does not enter the body through the skin.

Badger no longer uses zinc oxide nanoparticles in their sunscreens, but we stand by our original assertion that larger nanoparticles (>30nm) are safe when used in sunscreen creams.





Badger’s sunscreens have become extremely popular in the past few years, largely because our only active ingredient is the mineral zinc oxide. Starting in March of 2011 all Badger sunscreens use only uncoated non-nano sized particles of zinc oxide (the same kind found in calamine lotion and diaper rash cream).

Note: If your Badger sunscreen does not have our non-nano logo then it is from an earlier batch of sunscreen. These earlier sunscreens used a zinc oxide powder particle sized ranged from 70-300nm, so a fraction of the zinc oxide is below 100nm (the upper limit for nanoparticles). We used this particle size because it provided excellent UVA and UVB protection, relatively little whitening, and all scientific literature shows that particles in this size range do not penetrate the skin and are complete safe.

What size particles of zinc oxide does Badger use now?

We wanted to make sure we got this one right, so we had our new non-nano sunscreen formulas tested by an independent laboratory. Using a machine called the Saturn Digisizer 5205 (cool huh?) they determined that our zinc oxide particle size has a mean of 6.88µm (6880nm), a median of 0.79µm (790nm), and a range from 0.12µm (120nm) to 51.58µm (51580nm). A µm is a micrometer, or one millionth of a meter. A nm is a nanometer, or one billionth of a meter. Nanoparticles are particles between 1 and 100nm. Since our smallest particle size is 120nm we can confidently claim that our zinc oxide is non-nano. Here is a chart of the size distribution of our zinc oxide:

sunscreen zinc oxide size distribution

zinc oxide sunscreenWhat is the zinc oxide nanoparticle controversy about anyway?

When a substance is so small that it is measured in nano-meters (1 to 100 billionths of a meter) the surface area to volume ratio is so great that the properties of the substance may change. One comprehensive review of the scientific literature (1) shows that particles of zinc oxide greater than 30nm do not exhibit characteristics any different than those of larger sized particles. Well intentioned groups such as “Friends of the Earth” and “Consumer Reports” popularize the nanoparticle controversy by highlighting the potential health risks caused by nanoparticles if they were to enter deeper tissues, the blood, or the lungs. Science overwhelmingly shows that particles of zinc oxide greater than 30nm, when applied to the skin, do not get absorbed into the body, do not enter the bloodstream, and are not a threat to human health.(1)(2)(3)(4)(5) There are no studies showing that nanoparticles of zinc oxide can penetrate healthy human skin, whereas there are several studies showing that chemical sunscreen ingredients, which are molecular in size and thus significantly smaller than nanoparticles, are absorbed into the blood. The biggest concern with nanoparticles in cosmetics is the threat of inhalation with powders. This is not a concern when the powder is dispersed in a cream base. Even the Environmental Working Group recommends the use of nano sized mineral sunscreens over chemical sunscreens.

Why did Badger switch to using non-nano zinc oxide?

We switched to using non-nano zinc oxide for two reasons. First, many of our customers asked us to stop using nanoparticles in our sunscreens. Second, we’ve discovered a new way of working with larger particle zinc oxide that makes our sunscreens just as effective while using less zinc oxide.

What does uncoated zinc oxide mean?

Many sunscreens use zinc oxide whose particles have been coated with an inert substance. The reasons for coating are usually to make small nanoparticles less reactive and to make them easier to mix with the base ingredients. Badger used coated zinc oxide for years, until we switched to using larger particles (which are less reactive than smaller particles) and we found a better way to mix uncoated zinc oxide into our base. The zinc oxide we now use in all our sunscreens is uncoated pharmaceutical grade zinc oxide, the same kind used in calamine lotion and diaper rash cream. We know that uncoated zinc oxide is somewhat more photoreactive than coated zinc oxide, but we belive that this is not a health risk. Read details in the next section.

Are there any health risks with zinc oxide?

Zinc oxide, and most powders, can be a health risk if inhaled. This is not a concern with zinc oxide in our cream based sunscreens. Zinc oxide can also be photoreactive, meaning that when it is exposed to UV light it can generate reactive oxygen species, or free radicals, which can damage living cells. This too is not a concern with the zinc oxide in our sunscreens because:

  1. The rate of reactivity is still very low (uncoated zinc oxide is less reactive than even coated titanium dioxide),
  2. Most researchers and health organizations agree that since zinc oxide sits on the outer, dead, layer of skin, any free radicals generated will not affect living cells below (4), and
  3. Our inactive ingredients (olive oil, cocoa butter, shea butter, vitamin e and seabuckthorn berry) are powerful antioxidants, or free radical scavengers, that absorb free radicals generated by the zinc oxide.

Are there any risks to marine or aquatic life with zinc oxide?

Accroding to the Ecological Information in the Zinc Oxide Material Safety Data Sheet "The product itself and its products of degradation are not toxic." Other forms of zinc, however, are soluable and potentially toxic, but not zinc oxide. Furthermore, most zinc introduced into aquatic environments attaches to other oxides, clay, and organic materials and settles into the sediment (EPA 1987).

How does zinc oxide work as a sunscreen?

Zinc oxide is one of 17 active ingredients approved by the FDA for use in sunscreens. When you apply zinc oxide sunscreen the particles sit on the outermost layer of your skin, the stratum corneum, where they scatter and absorb ultraviolet radiation, protecting your living skin below.  Zinc oxide is unique among sunscreen ingredients in that it is truly a broad spectrum blocker, protecting you from UVA, UVB and UVC.

What is zinc oxide and where does Badger’s come from?

Zinc oxide is the metal zinc that has been oxidized. The chemical formula is ZnO, 1 zinc atom and 1 oxygen atom held together by an ionic bond. Zinc oxide does occur in nature as the mineral zincite, but it is quite rare and commercially unavailable. Badger's zinc oxide is manufactured using 100% clean recycled zinc left over from other processes, and purified via distillation to pharmaceutical grade zinc oxide.

Isn’t zinc oxide just another chemical?

According to one common definition of a chemical “a substance with a distinct molecular composition that is produced by or used in a chemical process” yes, zinc oxide (ZnO) could be considered a chemical, as could salt (NaCl), water (H2O), and quartz (SiO2). Based on this definition even orange juice is just chemicals (sugar, water, citric acid, minerals & vitamins). We follow a more sensible approach in defining chemicals and we do not believe that zinc oxide is a chemical, especially when compared to carbon based sunscreen chemicals like octocrylene (C24H27NO2). Are we wrong in calling our products chemical-free? You decide. We challenge you to find a more natural sunscreen.


Why does Badger use zinc oxide as the only active ingredient?

We’ve determined that zinc oxide is the safest, most effective active sunscreen ingredient available. It is a mineral that sits atop your skin absorbing and scattering damaging UVA, UVB and even UVC rays before they reach your living cells. As a broad spectrum blocker with a time tested safety record, it is really the best active sunscreen ingredient for our products. There are so many scientific studies showing the potential negative health and environmental effects of chemical sunscreens we believe more than ever that zinc oxide is the safest sunscreen option. 

Why doesn’t every sunscreen just use zinc oxide?

Mainly because you have to use a lot of it (~20% of the formula) to get an SPF30 and this can be whitening on some skin types, so not everyone likes it. Also, it’s expensive. Have you noticed how cheap chemical based sunscreens are compared to mineral sunscreens? We think the peace of mind is worth the additional cost and a little whitening on the skin.

What does Badger think about titanium dioxide?

We think that titanium dioxide ok, but that zinc oxide is better. Titanium dioxide doesn’t protect from UVA rays as well as zinc oxide does. Honestly we think it’s received a worse rap than it deserves. For instance, a 2011 Swiss study (6) that likened titanium dioxide to asbestos was referring to its toxicity when inhaled, which is not a threat when it is in sunscreen creams. The media did not seem to understand this and wrote about the dangers of sunscreens containing titanium dioxide.

What does Badger think about chemical sunscreens?

We don’t like them. We are concerned about the potential toxic effects of the chemicals when they enter the body. Oxybenzone, for example, is in about 60% of sunscreens sold in the US. The US Center for Disease Control found that 97% of Americans have oxybenzone in their blood (7). This ingredient has been shown to disrupt normal hormone functions and some health professional are recommending that products containing this ingredient not be used on babies and kids because it may disrupt normal development of their hormonal systems. Also, some chemical sunscreen ingredients have been shown to cause coral bleaching. Read more about corals and sunscreen.

Wrap Up

Here at Badger we, and most natural health advocates, including Dr. Andrew Weil (8), believe that zinc oxide sunscreens are better for your health than chemical based sunscreens and better than exposing your skin to excessive sun without sunscreen. We follow all of the latest sunscreen research closely, and we remain convinced that our sunscreens at Badger are the most effective and the safest for human health and for the environment. The best protection from the sun is to stay in the shade or wear protective clothing and a hat. But if you’re going expose your skin to the sun you should protect it, and a zinc oxide sunscreen is the safest and most effective means to that end.

Towards a Definition of Inorganic Nanoparticles from an Environmental, Health and Safety Perspective.Auffan et. al. Nature Nanotechnology Sept. 13, 2009. 
(2) Environmental Working Group’s
Sunscreen Guide

(3) Germany’s Federal Institute for Risk Assessment (English website)
"A Review of the Scientific Literature on the Safety of Nanoparticulate Titanium Dioxide and Zinc Oxide in Sunscreens" by the Australian Government
FDAs Nanotechnology Scientific Research Website

(6) Amir S. Yazdi, et al. Nanoparticles activate the NLR pyrin domain containing 3 (Nlrp3) inflammasome and cause pulmonary inflammation through release of IL-1 and IL-1β PNAS 2010 107: 19449-19454.
Calafat AM, Wong L-Y, Ye X, Reidy JA, Needham LL 2008. Concentrations of the Sunscreen Agent Benzophenone-3 in Residents of the United States: National Health and Nutrition Examination Survey 2003–2004. Environ Health Perspect 116:893-897
(8) Dr. Andrew Weil M.D.’s Question and Answer Library