by the Carcinogenic Potency Project at the University of California, tests on animals did not reveal
any carcinogenic activity caused by bismuth oxychloride, and studies on animals back in 1975 also
failed to find any carcinogenicity of this mineral (Preussmann, Ivankovic 1975). While bismuth
oxychloride sounds similar to bismuth chloride, it’s not the same chemical. Bismuth chloride is
obtained by treating bismuth with hydrochloric acid and is indeed highly toxic. Bismuth oxychloride,
a naturally occurring mineral salt that produces a subtle shimmer in mineral makeup products, has
excellent antibacterial properties, and no study has ever shown any carcinogenic potential concerning
this mineral.
Another dispute over the safety of mineral makeup concerns its physical qualities. Smoothness and
long-lasting coverage in mineral makeup is achieved by pulverizing or “micronizing” minerals into
microscopic or even nanoparticle size, but some researchers say that such wonderful qualities of
mineral makeup come at a price. Experts from the Environmental Working Group claim that some
nanoparticles can have very different, and even toxic, properties than the same chemical in a
nonmicronized state.
Scientists are still trying to come to a definitive answer regarding the potential harm of zinc oxide
and titanium oxide nanoparticles. The only recent research referring to the irritation potential of zinc
and titanium oxide nanoparticles is a 2007 Scottish study showing that zinc chloride in nanoparticle
form can irritate the lungs (Wilson et al. 2007). However, be advised that zinc oxide and zinc
chloride are two different chemicals. Also in 2007, scientists at Boise State University in Idaho
confirmed that while zinc oxide nanoparticles had clear antibacterial action, they had minimal effects
on human cells (Reddy et al. 2007). Similar findings— that zinc oxide nanoparticles can kill both
gram-negative and gram-positive bacteria without harming human cells—have also been reported by
researchers of the University of South Dakota in February 2008 (Jones et al. 2008). If you prefer to
err on the side of caution, stick to pressed mineral powder and fluid mineral foundations that do not
require buffing in with a fluffy brush.
Iron oxide pigments and mica create most color variations in mineral makeup. Most of the iron
oxide pigments used in cosmetics are approved by the FDA. When used in extremely high
concentrations—for example, during tattooing and permanent pigmentation of eyebrows and lashes—
iron oxides can cause irritation, but in mineral makeup the concentration is far lower. If you have a
family history of allergies, you will be better off with plant-based kohl eyeliners instead of dark
mineral eye shadows.
Mineral Foundations: Not All Alike
Your foundation is going to sit on your face all day long, so going mineral helps you avoid
unnecessary synthetic fillers and preservatives contained in a conventional foundation. Cleverly
formulated mineral foundations will also help protect your face from sun exposure and excessive
sebum production.
Invented thirty years ago, mineral foundations are quickly becoming the hottest-selling mineral
makeup product. They come in powder and cream forms, packed in sifter jars and pump bottles.
Those who love and use mineral makeup praise the dewy, natural, long-lasting glow and ability to
layer the powder over problem areas without added bulk. Most important, pure formulations without
synthetic bulk are safer and better for sensitive and acne- or rosacea-prone skin, especially after