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Q: Hi Stephanie

What do you think about Mica? I am interested in stocking Johnny Concert products in my shop in the UK but they use a lot of mica. They also use Iron Oxide and Kaolin. Their make up looks great but do you think it is ok? Gotta be safer than most of the stuff on the market at the moment, but I would love to hear what you think.


A: Micas, iron oxides, and clays can be problematic when in loose powder form because they can be inhaled in irrtate lungs (or with chronic exposure in higher amounts, lead to talcosis, scar lung tissue, or even cause lung cancer [source]).  [See my article about Mineral Makeups for more information]

There is also a theory that micas are skin irritants, although there are no apparent studies in peer-reviewed journals to back up the claims.  Some people theorize that the jagged nature of mica particles create microscopic lesions on the skin that lead to skin sensitivity.  If you have sensitive skin and are using micas in your makeup, you may want to consider stopping the use of micas, as your condition may improve. 

Personally, I can tell when I'm wearing a makeup with micas---in a lip gloss, I'll get a scratchy feeling in the back of my throat from injesting small amounts of the lip gloss.  My eyes get itchy if I use eyeshadows (which usually contain micas).  It's something that I can live with on occassion, but that's one of the reasons that I don't wear makeup on a daily basis.  Personally, if you don't have skin sensitivity, and are not breathing in the mica powders, I would consider, at this time, micas not to be a problematic ingredient.  However, we have chosen not to add mica powders to our products, because they are not truly natural ingredients, and are actually synthetic. And, as with most mineral ingredients, there can be trace amounts of heavy metals present in micas.  From the FDA:

The subject color additives are manufactured by preparing a suspension of mica platelets, adding a solution of soluble salts of titanium, of iron, or of both, and a base to precipitate titanium hydroxide, iron hydroxide, or both onto the mica platelets. These particles are then heated (calcined) at temperatures up to 900 [deg]C. During the calcination, titanium hydroxide and iron hydroxide are converted into titanium dioxide, and iron oxide, respectively. The agency has reviewed the relevant data and information in the petition relating to the manufacturing and identity of the subject color additives.

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    Chemical of the Day - Q&A - Mica

Reader Comments (4)

So what do you suggest when wanting to color products without the use of actual dye?

Tue, January 4, 2011 | Unregistered CommenterShermaine

It depends on the product--for soaps and bath salts and other body products, I recommend just going with the natural color of the product or adding herbs or clays for decorative effect. For makeups, unfortunately, mineral pigments such as titanium dioxide and iron oxide are the only products available on the market today.

Tue, January 4, 2011 | Registered Commenter[Stephanie Greenwood]

What about using Zinc Oxide in sunblocks? Isn't that the same idea?

Mon, April 23, 2012 | Unregistered Commenterdes

Zinc oxide in nano form can be harmful, and breathed in as a powder can be harmful as well. However, a non-nano zinc in a sunscreen is usually going to be in liquid form so it wouldn't pose those risks.

Fri, April 27, 2012 | Registered Commenter[Stephanie Greenwood]

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