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

Electron's 1-D metallic surface state observed: A step for the prediction of electronic properties of extremely-fine metal nanowires in next-generation semiconductors February 9th, 2016

Nanoparticle therapy that uses LDL and fish oil kills liver cancer cells February 9th, 2016

Leading bugs to the death chamber: A kinder face of cholesterol February 8th, 2016

From allergens to anodes: Pollen derived battery electrodes February 8th, 2016

Personal Care

Ceapro Presents Unique Advantages of Its Disruptive Pressurized Gas Expanded Technology (PGX) at 2015 Composites at Lake Louise November 10th, 2015

Nanofilm Introduces Clarity AR Lens Cleaner for Anti-Reflective Superhydrophobic Lenses August 20th, 2015

Sediment dwelling creatures at risk from nanoparticles in common household products August 13th, 2015

Engineering a better 'Do: Purdue researchers are learning how August 4th, 2015

Safety-Nanoparticles/Risk management

Lithium battery catalyst found to harm key soil microorganism February 7th, 2016

Are some people more likely to develop adverse reactions to nanoparticle-based medicines? January 31st, 2016

Too-few proteins prompt nanoparticles to clump: Rice scientists: Blood serum proteins must find balance with therapeutic nanoparticles January 29th, 2016

FLEXcon shares insights on developments and safety guidelines in nanotechnology: FLEXcon hosted New England Nanotechnology Association event, discussing latest industry activities and innovations January 25th, 2016

Human Interest/Art

Rice to enter first international nanocar race: Five teams will participate in October 2016 event in France December 15th, 2015

Bionic liver micro-organs explain off-target toxicity of acetaminophen (Tylenol): Israeli-German partnership aims to replace animal experiments with advanced liver-on-chip devices August 17th, 2015

Omni Nano and Time Warner Cable Partner to Provide Nanotechnology Education to the Boys & Girls Clubs of Los Angeles: A $10,000 Donation to Benefit Youth of Los Angeles County's Boys & Girls Clubs August 4th, 2015

Kalam: versatility personified August 1st, 2015

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