July 22, 2013
By Kenneth Portier, PhD
Recently, manufacturers have introduced new sunscreen products that use titanium dioxide, a typical ultraviolet (UV) radiation blocker found in many sunscreens, formed into tiny nanoscale particles. Why use nanoscale titanium dioxide? Because at this small size the particles do not block visible light, and therefore the sunscreen is invisible when applied to the skin and at the same time provides protection from cancer-causing UV radiation.
Titanium dioxide is an excellent UV-blocker, but there has been some concern about its safety because in dry powder form, titanium dioxide is highly toxic when inhaled. The International Agency for Research on Cancer (IARC) classifies the dry powder form of titanium dioxide as possibly carcinogenic to humans.
It's not yet clear, though, whether other forms of titanium dioxide, such as the nanoparticles used in sunscreen, also pose a risk. More...
April 30, 2013
By Daniel Mark Siegel, MD, MS
Winter is ending and the temptation to shed some layers comes alive.
But if you do show off your body, pay attention -- particularly if you are a mole-y person with dozens of moles, especially funny looking irregular ones all over the place. You may have a condition called "dysplastic nevus syndrome" or "familial atypical multiple mole-melanoma syndrome," which makes you more likely to develop melanoma. Nevus is the fancy Latin word for "mole," which is a benign growth, but melanoma is a skin cancer that if not diagnosed and treated early can be lethal.
The difficulties of diagnosing melanoma
Fortunately, there are a lot more nevi (not nevuses) than melanoma. So how do you tell them apart? Sometimes it is easy for your doctor to reassure you, but other times, even with the use of the skilled eyes of the dermatologist and added magnification, dermoscopy, and other evolving imaging techniques, it's still not clear. In such cases, a biopsy is needed.
A biopsy is where all or part of a mole is removed, sent to the lab, and a report of the analysis comes back. Sometimes the report is straightforward and says "benign mole" with no need for further treatment. Other times it reports a melanoma with descriptive staging terms that guide further therapy. More...
May 26, 2011
By Vilma Cokkinides, PhD
As summer approaches, we get a lot of reminders to protect our skin from the sun with sunscreen, shade, hats, and long sleeves. What doesn't get mentioned as often is indoor tanning.
Indoor tanning has become popular among young adult women and teenage girls. One chief motivation is that they believe they look more attractive and healthy with a tan. Many teens and their parents think getting a tan indoors is safer than tanning in the sun. But the truth is that tanning booths, lamps, or sunbeds emit ultraviolet (UV) radiation, just as the sun does. And exposure to UV radiation - whether from the sun or from a man-made source -- can raise your risk of skin cancer. More...