Greenyarn, a Boston nanotech startup has developed advanced fabrics for consumers seeking eco-friendly alternatives to conventional materials and selling their advanced clothing and anti-odor socks. This apparel made of what is called “Eco-fabric” contains nanoparticles of a unique bamboo charcoal that grows in the mountains of Taiwan. This bamboo is the Moso Bamboo the world's most porous bamboo and hence its charcoal contains many pores in its structure, making it excellent for absorbing odor-causing chemicals, controlling temperature, and voiding moisture making it an ideal fabric for footwear or undergarments. The bamboo is also naturally biocidal, and safely inhibits the growth of bacteria and fungi.
Greenyarn has developed deodorizing socks, fungal control shoe insoles, and anti-ageing, facial mask moisturizers. The socks and insoles keep feet warm in winter and at the end of the day they do not smell anymore. The socks are 200 needle count, made using a patented "3-D knitting" technique making them highly comfortable to wear.
The web site “ Nanotechnology Law Report” gives the results of actual test against the above claim on nanotech socks. (See:http://www.nanolawreport.com/2009/11/articles/another-nanosilver-sock-study/)
Arizona State researchers have studied on the potential release of nanosilver particles from odor-killing socks during theoretical wash cycles. A new study from Switzerland examines the issue in further detail. Swiss Federal Laboratories for Materials Testing and Research conducted the study with the aim of determining "the amount and the form of Ag released during washing from nine fabrics with different ways of silver incorporation into or onto the fibers." The study generally found that when washed at low pH levels, there was little dissolution of nanoparticles from the textiles being tested. However, the researchers theorized that the use of bleach "can greatly accelerate the dissolution of Ag." The percentage of total silver emitted during one wash cycle for the fabrics varied between 1% and 45%. Almost 75% of the silver released was greater than 450 nm in diameter.