So, I decided that a Feathered Friends Osprey was the right bag for me – right fill weight, right size, good total weight. FF bags, as many of you may know, can be made with a fabric called NanoSphere, which takes a couple of ounces off the weight of the bag. However, nanotechnology has always given me pause, because of reports that nano particles can penetrate the skin and theoretically could cause harm, although I had not heard of any actual studies that had assessed health risks. I thought I should investigate, since I would like to order that NanoSphere fabric and save a couple of ounces and also because nano particles may also appearing in other outdoor clothes and gear. For instance, the anti-bacterial silver additive may be nano-silver. Nano-textiles can also apparently be manufactured that have “heat conductive/isolating” properties and for UV protection, both of which may turn up in items purchased for outdoor use. What I found, however, was – well, not much. I don’t know if anyone is interested in this, but I thought that I would put what I found out there for anyone who might have an interest, and maybe others can add if they know anything this subject.
NanoSphere. I found nothing about NanoSphere except the claims of the manufacturer. The following if from Schoeller’s FAQ at http://www.nano-sphere.ch/index.php?id=44.
"Can the nanoparticles come adrift?
No, because they are bound into a specially developed coating matrix which ensures that the millions of nanoparticles on the fabric's surface cannot come adrift so there is no danger that they will dissolve during washing, dry cleaning or ironing. Today’s nanoparticles are thermo-stable up to 1700°C.
"Does the new NanoSphere® finish have nano certification?
The new formulation has been examined by internationally renowned Hohenstein Research Institute. In original state and after mechanical exposure to 5000 abrasion cycles and 30 wash cycles (with subsequent heat treatment) the finish is certified as having a very high and lasting level of hydrophobic and oleophobic properties. "The new NanoSphere® finish is undoubtedly a nanotechnology," confirms Dr. Jan Beringer, the institute’s Head of Testing and Director of the Textile Services and Innovations Department. "We also tested the biological safety for possible biological activity (cytotoxicity and genotoxicity* or HET-CAM). NanoSphere® passed all tests with excellent ratings and is safe."
*Skin tolerance and the possible behavior in service have been examined through cytotoxicity and genotoxicity testing. In the cytotoxicity test, which is recognized and mandatory for all medical products, measurements are carried out to determine whether cell-toxic substances could be released during use. The genotoxicity test examines the possibility of a mutagenic effect of the chemical substances. Neither test revealed biological activity. Indicators for possible skin irritation or signs of a fabric intolerance were also examined. The HET-CAM, also known as the hen's egg test, is a process for examining the skin-tolerance of chemicals. The abbreviation stands for hen's egg test on chorioallantoic membrane.
"How can we be sure that no nano particles come adrift?
NanoSphere® is being applied for years among other things in the Swiss operation of Schoeller Textile AG. In order to proactively examine the working conditions and the safety of the staff as well as those processing the materials in the textile chain and the consumer, elaborate waste air measurements were taken by a neutral body. The result: Not a single nanoparticle could be found. Everything is "under control" and there is no risk to staff, consumers, air or waste water."
It all sounds so groovy, but I would feel a lot better with more detailed information from an independent researcher. NanoSphere has received the “bluesign” certification as environmentally benign. I’m not sure who does the “bluesign” certification; it looks to me like it may be some kind of an industry group, but I really don’t understand its relationship to the manufacturers. I don’t know if this certification is meaningful or not, but a lot of companies, including Patagonia and REI, seem to be associated with it according to its website.
Other products using nano particles. I found the following paper from the Institute of Technology Assessment of the Austrian Academy of Sciences’ “Nano Trust Dossier,” dated December 2010. http://epub.oeaw.ac.at/ita/nanotrust-dossiers/dossier015en.pdf. The paper gives an overview about nano textiles and what is known about the potential effects on the environment and health of nano textiles. Basically, it concludes that nano particles can be released into the environment through washing, abrasion, aging, etc., but that there are little in the way of studies that establish our exposure and the extent to which nano particles may or may not be harmful to consumers’ health.
The paper notes that nano-silver is presently used for its antimicrobial properties in a wide range of consumer products and textiles and that nanoparticles are released during washing to varying degrees depending on the manufacturing process (up to 35% in a single wash) and enter the environment via the waste water. Silver ions are toxic for aquatic organisms and for microorganisms in the soil. The article notes that damage to the bacteria used in the biological purification of waste water in sewage plants cannot be ruled out. Nano-titanium dioxide, also used in the manufacture of nano-textiles, may also be problematic in the environment. When water and UV exposure are present nano-titanium dioxide produces free oxygen radicals which are toxic for aquatic microorganisms. “This can damage the ecological balance of stretches of water.” The article emphasizes that there have been no studies of the impact of these substances on ecosystems.
