PORTLAND, Ore. Semiconducting nanoparticles known as quantum dots can penetrate the skin with unknown health effects, according to researchers at the University of Rochester Medical Center.
The New York state researchers warned that engineering personnel handling materials based on quantum dots should take extra care to avoid physical contact with what they called potential "biohazards."
Lisa DeLouise, a University of Rochester doctor, claimed nanoparticles accumulate around hair follicles and folds of skin, and some are small enough to slip between the natural gaps between skin cells. DeLouise did not investigate medical effects, but cited other researchers' results that found that nanoparticles accumulate in the lungs, lymph system, liver and brain tissue.
DeLouise used fluorescent quantum dots to simplify tracking and identifying their precise location and migration paths. After illuminating them with ultraviolet light, she discovered that skin damaged by UV light showed bigger gaps that made it easier for nanoparticles to penetrate skin.
Nanoparticles as small or smaller than quantum dots are already being mass produced for consumer applications that contact skin, including sunscreens made transparent by reducing their active ingredient to 10-nanometer particles.
Next DeLouise plans to study titanium dioxide and zinc oxide nanoparticles, both of which are already available in sunscreens often used on sun-burned skin already damaged by UV rays.