- Do Silver nanoparticles come off the fabrics in which they are embedded? Apparently they do, but different fabrics lose nanoparticles at different rates, at least during the wash cycle.
- Can silver nanoparticles be absorbed into or through skin? Apparently they can and have been shown to cause ill effects in laboratory tests of skin cells.
- How long do silver nanoparticles stay in a person once they get there? This is an important question. If they stay around a long time, they can do damage for a long time. If they leave quickly they would be less dangerous. Same thing goes for a lot of other substances. The answer to this question appears to be unknown
- Are there any known health effects if silver nanoparticles are absorbed? Silver nanoparticles appear to have harmful effects on some human (and animal) cells including nerve cells and interfere with synthesis of seleno-proteins. Seleno-proteins are important anti-oxidants and detoxifying enzymes. This means someone might show the effects of selenium deficiency even though dietary intake was adequate.
South Central CrossFit Regional Athlete Mackey Hermosillo finds an alternative means of protection against odor.
While its been demonstrated that the particles can harm cells, tissues or organs we don’t know how much would be needed to harm health. The amount of silver nano-particles absorbed from clothing may not be high enough to matter. Its an unanswered question. We’ll probably hear more about this in coming years. For now we recommend against using, eating or wearing things if we aren’t sure if they are going to bite us in the ass later.
Back to Lulu and Reebok and CrossFit Clothing.
Lulu Lemon uses silver nanoparticles for their anti-microbial fabrics. We could not find any information on Reebok and silvernanoparticals, so we are assuming they are not using them. On a positive note for Lulu, their silver nanopartical shirts really work for stink prevention. We tested one by wearing it for two weeks straight on a challenging backpacking trip and it smelled fine.
Benn TM, & Westerhoff P (2008). Nanoparticle silver released into water from commercially available sock fabrics. Environmental science & technology, 42 (11), 4133-9 PMID: 18589977
Brandt O, Mildner M, Egger AE, Groessl M, Rix U, Posch M, Keppler BK, Strupp C, Mueller B, & Stingl G (2012). Nanoscalic silver possesses broad-spectrum antimicrobial activities and exhibits fewer toxicological side effects than silver sulfadiazine. Nanomedicine : nanotechnology, biology, and medicine, 8 (4), 478-88 PMID: 21839058
Lim DH, Jang J, Kim S, Kang T, Lee K, & Choi IH (2012). The effects of sub-lethal concentrations of silver nanoparticles on inflammatory and stress genes in human macrophages using cDNA microarray analysis. Biomaterials, 33 (18), 4690-9 PMID: 22459196.