Nanotechnology Now







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

Nanosensor Used for Simultaneous Determination of Effective Tea Components January 24th, 2015

New technique helps probe performance of organic solar cell materials January 23rd, 2015

Iranian Scientists Produce Graphene-Based Oxygen Sensor January 23rd, 2015

Silver nanowires demonstrate unexpected self-healing mechanism: The material has potential for flexible electronics January 23rd, 2015

Personal Care

Sunblock poses potential hazard to sea life August 20th, 2014

AQUANOVA receives Technology Leadership Award 2014 FROST & SULLIVAN honors NovaSOL® Technology again August 12th, 2014

Nanotechnology used in sunscreens: a Mexican achievement May 14th, 2014

Production of Nanocapsule from Sea-Buckthorn Extract in Iran May 3rd, 2014

Safety-Nanoparticles/Risk management

A spoonful of sugar in silver nanoparticles to regulate their toxicity January 21st, 2015

Nutrition, Safety Key To Consumer Acceptance of Nanotech, Genetic Modification In Foods December 2nd, 2014

Sustainable Nanotechnologies Project November 20th, 2014

A gut reaction November 19th, 2014

Human Interest/Art

OCSiAl supports NanoART Imagery Contest January 23rd, 2015

EnvisioNano: An image contest hosted by the National Nanotechnology Initiative (NNI) January 22nd, 2015

Oxford Instruments Asylum Research Announces AFM Image Contest Winners January 11th, 2015

Longhorn beetle inspires ink to fight counterfeiting November 5th, 2014

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







© Copyright 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE