There's been some debate about the safety of nano-sized particles of zinc oxide and titanium dioxide in sunscreens-- one of the scenarios discussed in the NISE Net's Nanomedicine in Healthcare forum  relates to using nano-sized particles of zinc oxide in sunscreen. However, one consumer group recently weighed in that maybe nano sunscreens are okay. As a very pale person with a family history of skin cancer, I like to keep up with sunscreen news, so I was interested to see Andrew Maynard tweeting  that "...Industry critics give nanotechnology sunscreens the thumbs up." He had written a blog post  (which includes a good discussion in the comments) about an Environmental Working Group  report  on the safety of micronized and nano-sized zinc oxide and titanium dioxide suncreens. They ended up "recommending some sunscreens that may contain nano-sized ingredients." The big deal about nanosized zinc oxide and titanium dioxide particles in sunscreens is that they appear clear, rather than white, and may not come with some of the risks of chemical sunscreens. Read the full report here . Interested in sunscreen-related activities?
- The NISE Net's Nanoparticle Stained Glass cart activity  lets visitors explore how changes in the size of a particle affect the color of the particles, a change in properties similar to that in sunscreens with nanosized particles. Check out the "program specific background" section for more information.
- Dragonfly TV's Stained Glass Activity Guide  includes an investigation of nano sunscreens (and thank you, Lisa, for sending me this and other nano sunscreen links!)
- NanoSense , an NSF-funded project creating curriculum units for high school students and teachers on nanoscale science, has developed a unit on Clear Sunscreen: How Light Interacts with Matter. 
- And finally, The Franklin Institute developed an activity on sunscreen . Last week I ran into Jayatri Das from the Franklin who said that she was planning to add her activity to the NISE Net catalog this week. Update: Jayatri just added it to the catalog , thank you, Jayatri!