Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button


DHgate

Home > News > Screen Test: Reading the Micro-Fine Print

May 23rd, 2007

Screen Test: Reading the Micro-Fine Print

Abstract:
Mineral sunblocks that contain titanium dioxide (TiO2) or zinc oxide (ZO) are preferable to chemical sunscreens, because rather than being absorbed into the skin, the minerals lie on top of the skin, reflecting UV rays before they cause damage. The choice of most lifeguards, these sunblocks are famous for giving off that unattractive "white" mask.

But this is where problems with minerals arise. In order to reduce the visibility of sunscreen, many manufacturers use nanometer-sized particles of TiO2 and ZO. A nanometer (nm) is about a billionth of a meter—a unit so small that a single human hair is about 80,000 nm in diameter. The U.S. government has defined nanomaterials as particles smaller than 100 nm, and according to the Australian government, most nano-sized sunscreens use particles that size or smaller because the sunscreens become transparent on skin.

Nanoparticles are unpredictable because their small size and high ratio of surface area to volume can produce chemical or physical properties that are very different from their larger counterparts. For instance, once TiO2 nanoparticles enter the bloodstream, they are at risk of infiltrating the brain where they can damage cells, whereas larger micron-sized (millionths of a meter) particles of TiO2 are blocked by the blood-brain barrier, which protects the brain from harmful substances in the bloodstream. Fortunately, the consensus in the scientific community, as demonstrated by a 2006 Australian government literature review on the topic, is that neither TiO2 nor ZO penetrate the skin deep enough to actually enter the bloodstream.

Source:
thegreenguide.com

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

Automating DNA origami opens door to many new uses: Like 3-D printing did for larger objects, method makes it easy to build nanoparticles out of DNA May 30th, 2016

Simple attraction: Researchers control protein release from nanoparticles without encapsulation: U of T Engineering discovery stands to improve reliability and fabrication process for treatments to conditions such as spinal cord damage and stroke May 28th, 2016

Scientists illuminate a hidden regulator in gene transcription: New super-resolution technique visualizes important role of short-lived enzyme clusters May 27th, 2016

Doubling down on Schrödinger's cat May 27th, 2016

Personal Care/Cosmetics

Programmable materials find strength in molecular repetition May 23rd, 2016

Common nanoparticle has subtle effects on oxidative stress genes May 11th, 2016

NRL reveals novel uniform coating process of p-ALD April 21st, 2016

New ORNL method could unleash solar power potential March 16th, 2016

Safety-Nanoparticles/Risk management

PETA science group publishes a review on pulmonary effects of nanomaterials: Archives of Toxicology publishes a review of scientific studies on fibrotic potential of nanomaterials May 26th, 2016

Common nanoparticle has subtle effects on oxidative stress genes May 11th, 2016

Non-animal approach to predict impact of nanomaterials on human lung published Archives of Toxicology publishes workshop recommendations May 2nd, 2016

Scientists propose non-animal tools for assessing the toxicity of nanomaterials: Particle and Fibre Toxicology publishes recommendations from expert group meeting April 26th, 2016

Human Interest/Art

Scientists propose non-animal tools for assessing the toxicity of nanomaterials: Particle and Fibre Toxicology publishes recommendations from expert group meeting April 26th, 2016

Are humans the new supercomputer?Today, people of all backgrounds can contribute to solving serious scientific problems by playing computer games. A Danish research group has extended the limits of quantum physics calculations and simultaneously blurred the boundaries between mac April 14th, 2016

UCLA nanoscientists engage shoppers in fun conversations March 8th, 2016

Risk Analysis Publishes Non-Animal Strategy to Assess Nanomaterials February 24th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic