BOB HIRSHON (host):
Nanoparticles and your skin….I’m Bob Hirshon and this is Science Update.
Protecting skin from the sun’s harmful rays once required a thick white layer of zinc or titanium oxide. But today, many sunscreens are invisible. That’s because scientists have shrunk these oxide particles down to the nanometer scale, thousands of times smaller than the width of a human hair. Biomedical researcher Lisa DeLouise of the University of Rochester School says nearly 600 consumer products containing nanoparticles are currently on the market, many of them cosmetics.
LISA DELOUISE (University of Rochester School of Medicine.):
So it’s the natural question to ask, whether these particles could penetrate through skin.
She and her colleagues found that a liquid containing nanoparticles penetrated much more deeply into previously sunburned skin that it did into healthy skin.
She says that their high surface-to-volume ratio makes nanoparticles more reactive, which could pose a potential health risk if skin is damaged. I’m Bob Hirshon, for AAAS, the science society.