> nanoparticles cause male reproductive cells to stop growing.
>
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>
> Minute materials used in a number of consumer
> products such as antimicrobial agents can
> interrupt important cell signaling within male
> reproductive sperm cells, causing them to stop
> growing, according to a new study that builds on
> previous work by the same research group.
>
> In prior studies, the scientists reported how
> smaller-sized silver nanoparticles – in the 10 -
> 25 nanometer range – decreased the growth of male
> stem cells when they were exposed at
> concentrations greater than 10 micrograms per milliliter ( g/ml).
>
> The new study is the first to identify how the
> silver nanoparticles stop the sperm stem cells
> from growing. The biggest effects were caused by
> the smallest-sized nanoparticles tested.
>
> This study raises important questions about
> potential effects on male fertility, because
> silver nanoparticles are currently used in a wide range of products.
>
> In addition, exposure during development may
> affect forming sperm cells and lead to birth
> defects related to the male reproductive system.
> Scientists believe this is because the small
> silver particles can cross the mother's placenta and directly affect the baby.
>
> Silver has long been recognized as a powerful
> antimicrobial. As such, the use of silver
> nanoparticles – ultra-small particles with
> diameters less than 100 nanometers – as
> antimicrobial coatings for clothing and bandages
> has boomed. Air sanitizers and personal care
> products also contain the nanoparticles.
>
> Little information is available about how their
> widespread use translates into actual human
> exposures. Most likely, people breathe, eat or
> absorb them, especially if they manufacture or
> work with them. Consumer products may be another
> source. A growing number of studies find the
> silver particles do not remain in the products in
> which they are incorporated. They can migrate out
> of clothing and into artificial sweat
> (Correction, 9/2/10: that was used in the study
> to simulate perspiration). During washing, the
> silver can leach into the washwater and be
> carried by wastewater into the environment.
>
> Health effects are even less understood, but
> studies to date have led experts to raise
> concerns. Because of their small size,
> nanoparticles can easily travel through the
> bloodstream and reach tissues – including the
> testes – after being inhaled or via other exposure pathways.
>
> Previous laboratory studies show the silver
> nanoparticles are toxic to different types of
> cells, including lung, nerve and skin cells. They
> are also able to cross into the brain and travel
> through the blood to other body tissues. Some
> types of nanoparticles can cross the placenta,
> both human and animal studies show.
>
> Spermatogenesis is the complex process in the
> testes that ultimately produces sperm.
> Environmental agents that slow the growth and
> proliferation of these cells may cause low sperm
> numbers and impact male fertility.
>
> Using a cell line of mouse sperm stem cells, the
> researchers tested the effects of different
> sizes, concentrations and coatings of silver
> nanoparticles on cell growth. They compared
> silver nanoparticles coated with either
> hydrocarbons – at 15 nm, 25 nm and 80 nm
> diameters – or sugars – at 10 nm, 25 - 30 nm and 80 nm diameter.
>
> Exposure to the smaller sized particles led to
> increased stem cell death. The coatings were
> important, too. The sugar coatings on the
> smaller-sized silver nanoparticles increased the
> production of reactive oxygen species (ROS), one
> of the signals for induced cell death.
>
> One pathway known to be important for sperm stem
> cell growth is the growth factor glial cell
> line-derived neurotrophic factor (GDNF). The
> researchers found that while the amount of GDNF
> was not changed, the signals sent to the cell
> were damaged after silver nanoparticle exposure.
> Upon a closer look, they found that a small
> protein, Fyn kinase, was not fully functional.
> This protein requires a modification in order to
> function, and that modification was reduced when
> cells were exposed to silver nanoparticles.
>
> An important limitation for this study is the
> lack of information on how the concentrations of
> silver nanoparticles used in this study relate to
> human exposures. Further, it is unclear whether
> these concentrations would be achieved within the testes.
>
> < http://www.environmentalhealthnews.org>
> © EnvironmentalHealthNews 2003-2004
>
> Search
>
> 1 September
> < http://www.environmentalhealthnews.org/ehs/newscience/silver-nanoparticles-impair-sperm-stem-cell-signals/ >Silver
> nanoparticles stop sperm stem cell growth. Minute
> silver nanoparticles-- widely used in consumer
> products as antimicrobial agents-- can cause
> sperm cells to stop growing, according to a new
> study. < http://www.environmentalhealthnews.org>Environmental Health News.
>
> 14 August
> < http://www.newscientist.com/article/mg20727735.300-antibacterial-socks-may-boost-greenhouse-emissions.html >Antibacterial
> socks may boost greenhouse emissions. A research
> team has discovered that wetland microbes give
> off more nitrous oxide, a greenhouse gas, when
> exposed to silver nanoparticles.
> < http://archive.newscientist.com>New Scientist.
>
> 10 August
> < http://www.scientificamerican.com/article.cfm?id=silver-beware-antimicrobial-nanoparticles-in-soil-may-harm-plant-life >Silver
> beware. Silver nanoparticles, used for their
> potent antimicrobial properties in hospitals and
> consumer products, may negatively impact plant
> growth as they make their way into the
> environment, according to a new study.
> < http://www.scientificamerican.com>Scientific American.
>
> 30 July
> < http://www.theepochtimes.com/n2/content/view/40070/>Regulation
> for nanotech an absolute must. Nanotechnology is
> rapidly becoming pervasive reality in New
> Zealand, but where are the checks and balances to
> protect consumers, workers and the environment,
> asks the Sustainability Council. < http://www.theepochtimes.com>Epoch Times.
>
> 27 May
> < http://www.newscientist.com/article/mg20627611.100-the-taste-of-tiny-putting-nanofoods-on-the-menu.html >The
> taste of tiny: Putting nanofoods on the menu.
> Nanotechnology promises even saltier-tasting
> salt, less fattening fat, and more nutritional
> food products. Nanofood supplements could even
> tackle global malnutrition. Yet trust and
> confidence depend on whether new products can be
> shown to be safe. < http://archive.newscientist.com>New Scientist.
>
> 30 April
> < http://www.environmentalhealthnews.org/ehs/newscience/fabrics-release-silver-nanoparticles-into-artificial-sweat/ >Treated
> fabrics exposed to faux sweat release silver
> nanoparticles. Researchers find that fabrics
> laced with silver nanoparticles designed to limit
> bacterial growth release those particles when the
> fabric is exposed to artificial human sweat.
> < http://www.environmentalhealthnews.org>Environmental Health News.
>
> 27 March
> < http://www.theaustralian.com.au/news/health-science/big-issues-with-small-science-nanotechnology/story-e6frg8y6-1225845537880 >Big
> issues with small science: Nanotechnology.
> Friends of the Earth is targeting cosmetic giant
> L'Oreal for incorporating nanoparticles in its
> posh potions and lotions. The environmental group
> contends that nano-products, including cosmetics
> and sunscreens, could present serious new health
> and environmental risks.
> < http://www.theaustralian.news.com.au>Sydney Australian, Australia.
>
> 7 January
> < http://www.environmentalhealthnews.org/ehs/newscience/silver-migrates-from-nanoparticle-treated-fabrics/ >Silver
> migrates from treated fabrics. Silver
> nanoparticles used as antimicrobials in fabric
> can leach out of clothes as they are being
> washed. One brand lost over half of its silver
> content from the fabric with just two washings.
> < http://www.environmentalhealthnews.org>Environmental Health News.
>
> 8 December
> < http://www.sciencenews.org/view/generic/id/50519/title/Batteries_made_from_nanotubes...and_paper >Batteries
> made from nanotubes...and paper. Scientists have
> made batteries and supercapacitors with little
> more than ordinary office paper and some carbon
> and silver nanomaterials, bringing us closer to
> lightweight printable batteries that may one day
> be molded into computers, cell phones or solar
> panels.. <http://www.sciencenews.org >Science News.
>
> 17 November
> < http://www.environmentalhealthnews.org/ehs/news/nanosilver >Nanosilver
> in consumer products: No silver lining for fish.
> Smaller than a virus and used in more than 200
> consumer products, silver nanoparticles can kill
> and mutate fish embryos, new research shows.
> Increasingly popular in consumer goods, they wash
> down drains and are discharged into lakes and
> rivers, exposing fish and other aquatic life.
> < http://www.environmentalhealthnews.org>Environmental Health News.
>
> 6 November
> < http://www.abc.net.au/news/stories/2009/11/06/2735612.htm>More
> evidence nanoparticles damage DNA. Researchers in
> the United Kingdom have found some nanoparticles
> - which can be found in common household items -
> can damage DNA without even penetrating the
> cells. <http://www.abc.net.au>Sydney ABC News, Australia.
>
> 6 November
> < http://www.nytimes.com/2009/11/03/science/03obsox.html>Anti-odor
> silver exits textiles in the wash. Silver ions
> are such effective antimicrobial agents that
> there are now hundreds of consumer products that
> contain small amounts of the metal, in the form
> of nanoparticles that release ions slowly over
> time. <http://www.nytimes.com>New York Times.
>
> 2 November
> < http://www.startribune.com/business/67823902.html>Nanotechnology:
> A risky frontier? Nanotechnology already has
> found hundreds of high-tech uses. But do its tiny
> particles pose big health risks? That
> uncertainty, and companies' reluctance to embrace
> the field, cloud its future.
> <http://www.startribune.com >Minneapolis Star Tribune, Minnesota.
>
> 30 September
> < http://www.sciencenews.org/view/generic/id/47913/title/Science_%2B_the_Public__EPA%E2%80%99s_nanotoxicity_research_blueprint >EPA's
> nanotoxicity research blueprint. The EPA issued a
> news release this afternoon saying that it had
> today outlined a new research strategy to better
> understand how manufactured nanomaterials may
> harm human health and the environment.
> Interesting as that strategy document is, it was
> hardly hot off the presses. <http://www.sciencenews.org >Science News.
>
> 8 August
> < http://www.scientificamerican.com/article.cfm?id=carbon-nanomaterials-bad-for-fruit-fly-coating >Carbon
> nanomaterials: Fine for fly food, bad for fly
> coating. Buckyballs and other nano carbon
> particles seem to be fine when served as baby
> food to fruit fly larvae, but some kinds are
> deadly to the adults when the flies are coated
> with the infinitesimal stuff
> < http://www.scientificamerican.com>Scientific American.
>
> 11 July
> < http://www.stuff.co.nz/dominion-post/news/features/2584731/Keeping-harness-on-untamed-discovery >Keeping
> harness on untamed discovery. Nanotechnology
> could cure cancer, solve the energy crises and
> boost our economy, but will it take a catastrophe
> for the Government to regulate what scientists
> are calling the next industrial revolution?
> <http://www.stuff.co.nz >Wellington Dominion Post, New Zealand.
>
> 12 June
> < http://www.abc.net.au/science/articles/2009/06/12/2594441.htm>Call
> for control of nano-silver use. The widespread
> use of antibacterial silver nanoparticles in
> consumer products should be kept in check, say
> experts. <http://www.abc.net.au>Sydney ABC News, Australia.
>
> 18 May
> < http://www.palmbeachpost.com/business/content/business/epaper/2009/05/17/0517nanotech.html >The
> smaller, the better? With pharmaceutical giants
> Bayer, BASF, and Pfizer, and energy companies
> like Exxon Mobil furiously pursuing
> nanotechnology projects, a number of consumer
> groups are raising the alarm about potential
> health threats of nano- particles accumulating in
> the body. < http://www.palmbeachpost.com>Palm Beach Post, Florida.
>
> 5 May
> < http://www.smh.com.au/national/nsw-pushes-for-nano-risk-labels-20090504-asmk.html >NSW
> pushes for nano risk labels. The NSW Government
> will push for national mandatory labelling of
> nano-sized particles used in workplaces and
> improved testing facilities to assess the safety
> of new nanomaterials. <http://www.smh.com.au>Sydney Morning Herald, Australia.
>
> 23 April
> < http://www.smh.com.au/lifestyle/wellbeing/no-needles-in-a-nano-universe-20090422-affk.html >No
> needles in a nano universe. One of the first
> applications of nanotechnology in medicine could
> be a painless vaccine "nanopatch" being developed
> by Australian scientists that could bring
> protection against deadly diseases to people in
> remote areas where there is a lack of
> refrigeration or disposable syringes.
> <http://www.smh.com.au>Sydney Morning Herald, Australia.
>
> Sheri Nakken, R.N., MA, Hahnemannian Homeopath
> Vaccination Information & Choice Network, Washington State, USA
> Vaccines -
> http://vaccinationdangers.wordpress.com/
> Homeopathy http://homeopathycures.wordpress.com
> Vaccine Dangers, Childhood Disease Classes &
- > Homeopathy Online/email courses - next classes start September 2010
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