New Products Bring Side Effect: Nanophobia

IT sounds like a plot straight out of a science-fiction novel by Michael Crichton. Toiletry companies formulate new cutting-edge creams and lotions that contain tiny components designed to work more effectively. But those minuscule building blocks have an unexpected drawback: the ability to penetrate the skin, swarm through the body and overwhelm organs like the liver.

Humans have long lived in dread of such nightmare scenarios in which swarms of creatures attack. Alfred Hitchcock envisioned menacing flocks in “The Birds.” In the 1990 film “Arachnophobia” a killer spider arrives in the United States, where it attacks and multiplies.

And now comes nanophobia, the fear that tiny components engineered on the nanoscale — that is, 100 nanometers or less — could run amok inside the body. A human hair, for example, is 50,000 to 100,000 nanometers in diameter. A nanoparticle of titanium dioxide in a sunscreen could be as small as 15 nanometers. (One nanometer equals a billionth of a meter.)

“The smaller a particle, the further it can travel through tissue, along airways or in blood vessels,” said Dr. Adnan Nasir, a clinical assistant professor of dermatology at the University of North Carolina at Chapel Hill. “Especially if the nanoparticles are indestructible and accumulate and are not metabolized, if you accumulate them in the organs, the organs could fail.”

http://www.nytimes.com/2008/12/04/fashion/04skin.html?th&emc=th

for acne cleansers containing salicyclic acid and benzoyl peroxide, my face finally cleared up!