The Lowdown on Mineral Makeup

Mineral Makeup: Not All Alike continued...

That's because within the brands that claim "pure mineral" formulations, there is still another category breakdown -- those that contain an arguably "natural" mineral known as bismuth oxycholoride, and those that do not.

A pearlizing agent that gives mineral makeup that "candlelight glow," bismuth oxychloride is a mineral, but it's not found in the earth. Bismuth is a byproduct of lead and copper processing. Bismuth oxychloride is also frequently used to fill or "bulk up" or bind products, says Adams, and some say it comes with a heavy price.

"Bismuth oxychloride is considered a skin irritant and can cause itching and rashes and in large amounts it can cause cystic acne as well – it's one of the ingredients you should try to avoid if you have acne or rosacea or sensitive skin," says Frew, who also reminds us that some products in a line have this ingredient, while others do not. "Some products also contain very little, so it doesn't act like an irritant, but you won't know until you try it."  

To find out if there are any known toxic effects from ingredients in your makeup, go to Skin Deep at www.cosmeticsdatabase.com and enter a product name or ingredient.

Mineral Makeup: Buyer Beware

One of the factors that makes mineral makeup so popular is the smooth, natural, long-lasting coverage -- a feat that's some companies accomplish by pulverizing or "micronizing" their minerals into microscopic or even nanoparticle size.  

But some researchers say this activity may come with a price.

"Research shows that when some molecules are dramatically reduced in size to the level of a nanoparticle, they can have very different and very toxic properties than that same molecule would have in its conventional size," says Jane Houlihan, research director of consumer watchdog agency The Environmental Working Group in Washington.

"Minerals like zinc and titanium are safe when applied to healthy skin but in a micronized nanoparticle form, there remains a concern, particularly when applied to damaged skin, or when inhaled," says Houlihan.

The bottom line: Even when beauty comes from the earth, it's still a case of beauty buyer beware.

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