Nanotechnology – promissory note on our future?

25 08 2010

“We see it (nanotechnology) as having virtually unlimited potential to transform the way we produce, deliver, and use energy, not to mention its likely effect on medical technology and national security.”
— U.S. Energy Secretary Spencer Abraham

Recently, I have been noticing various products claiming to have some kind of nanotechnology-based credential.  Turns out that’s because the nanotech tsunami is just gaining steam – one tally says that over 10,000 products using nanotechnology are already on the market.  In the food industry, the FDA says there are no nano-containing foods on the market in the U.S., yet DK Matai, Chairman of the Asymmetric Threats Contingency Alliance, says that the USA is the world leader in nano foods, followed by Japan, Europe and China[1].   The Environmental Working Group has done it’s own count of lotions, creams, sprays, washes, cosmetics and nutritional supplements on the market in the U.S. and has found close to 10,000 that contain nanoparticles.  And there’s an app for that:  The Project on Emerging Nanotechnologies has an iPhone app called findNano, which urges users to photograph and submit information on a possible nanotech product for inclusion in its inventory.

Eric Drexler,  in his 1986 book, Engines of Creation, pictured a world in which nanomachines no bigger than molecules run amok, consuming the planet’s resources and leaving nothing but grey goo. Other than reading about that apocalyptic event, I didn’t give nanotechnology much thought, since it didn’t seem to have much application to my own life.  Wrong again!

Turns out that there are many who think the next Industrial Revolution is right around the corner –  because of nanotechnology.  They think that nanotechnology  will radically transform the world, and the people, of the early 21st century.  It has the capacity to change the nature of almost every human-made object.  Whether that transformation will be peaceful and beneficial or horrendously destructive is unknown.   So naturally it’s become very controversial.   More about that later.

Nanotechnology as we now know it began about twenty years ago, when  research managers in the U.S. and other countries observed that physicists, biologists, chemists, electrical engineers, optical engineers, and materials scientists were working on interlocking issues at the nanoscale.  Realizing that these researchers could benefit from each other’s insights, they set up a coordinated program called the U.S. National Nanotechnology Initiative (NNI).  The National Nanotechnology Initiative  hopes to promote a future in which the ability to understand and control matter at the nanoscale  will lead to a revolution in technology  that benefits society.  The Initiative coordinates the funding for nanotechnology research and development among twenty-five federal departments and agencies.

I’ll try to give some kind of overview of the questions being asked about nanotechnology so we can begin to grasp the concept before I talk about nanotechnology in textiles (next week) where it is widely used in antimicrobial finishes, soil and water repellant finishes – and as a replacement for dyestuffs.

First, it seems the better term is really nanoscience.  Nanoscience is the study of things that are really really small: A nanometer is one billionth of a meter (10-9 m). This is roughly ten times the size of an individual atom. For comparison, 10 NM is 1000 times smaller than the diameter of a human hair.  How small is that?   “If a centimeter is represented by a football field, a nanometer would be the width of a human hair lying on the field,” offers  William Hofmeister of the University of Tennessee Space Institute’s Center for Laser Applications. 

Nanoparticles are bits of a material in which all three dimensions of the particle are within the nanoscale:  nanotubes have a diameter that’s nanosize, but can be several hundred nanometers (nm) long or even longer.  Nanofilms or nanoplates have a thickness that’s nanosize, but their other two dimensions can be quite large.  These nanoparticles can be designed into structures of a specific size, shape, chemical composition and surface design to create whatever is needed to do the job at hand. They can be suspended in liquid, ground into a powder, embedded into a composite or even added to a gas.

When particles are purposefully manufactured with nanoscale dimensions, we call them engineered nanoparticles. There are two other ways nanoparticles are formed:  as a byproduct of combustion, industrial manufacturing, and other human activities (known as incidental nanoparticles) and through natural processes, such as sea spray and erosion.

Many important functions of living organisms take place at the nanoscale. The human body uses natural nanoscale materials, such as proteins and other molecules, to control the body’s many systems and processes. A typical protein such as hemoglobin, which carries oxygen through the bloodstream, is 5 nms in diameter.  Based on the definition of nanotech given above, biotech can be thought of as a subset of nanotech – “nature’s nanotechnology.”

Manipulating something so mind-bogglingly small is where the “technology” part comes in – it’s  about trying to make technologies, such as computers and medical devices, out of these nanoscale structures.  Nanotechnology is different from older technologies because unusual physical, chemical, and biological properties can emerge in materials at the nanoscale. Nano particles have different physical properties from their macro or life-size scale counterparts.  For example, copper is an opaque mineral, but at the nano scale it is transparent.  Some particles, like aluminum, are stable at macro scale but become combustible when reduced to nano-particles;  a gold nanowire is twenty times stronger than a large bar of gold.

Nanotechnology was first brought to public attention by Richard Feynman, in a talk given in 1959 at the meeting of the American Physical Society: “There’s Plenty of Room at the Bottom” .  During that talk, he explained:

“When we get to the very, very small world—say circuits of seven atoms—we have a lot of new things that would happen that represent completely new opportunities for design. Atoms on a small scale behave like nothing on a large scale, for they satisfy the laws of quantum mechanics. So, as we go down and fiddle around with the atoms down there, we are working with different laws, and we can expect to do different things… If we go down far enough, all of our devices can be mass produced so that they are absolutely perfect copies of one another. We cannot build two large machines so that the dimensions are exactly the same. But if your machine is only 100 atoms high, you …have to get it correct.”

I found this explanation of nanotechnology on the Foresight Institute website:

“The quality of all human-made goods depends on the arrangement of their atoms. The cost of our products depends on how difficult it is for us to get the atoms and molecules to connect up the way we want them. The amount of energy used – and pollution created – depends on the methods we use to place and connect the molecules into a given product. The goal of nanotechnology is to improve our control over how we build things, so that our products can be of the highest quality and while causing the lowest environmental impact.  Nanotech is even expected to help us heal the damage our past cruder and dirtier technologies have caused to the biosphere.  Traditional manufacturing builds in a “top down” fashion, taking a chunk of material and removing chunks of it – for example, by grinding, or by dissolving with acids – until the final product part is achieved. The goal of nanotechnology is to instead build in a “bottom-up” fashion, starting with individual molecules and bringing them together to form product parts in which every atom is in a precise, designed location. In comparison with the top-down approach, this method could potentially have much less material left over, greatly reducing pollution.”

Molecular manufacturing is the name given to a specific type of “bottom-up” construction technology. As its name implies, molecular manufacturing will be achieved when we are able to build things from the molecule up, and we will be able to rearrange matter with atomic precision.

As I mentioned earlier, something so little understood is controversial, with many different points of view. These differences start with the very definition of nanotechnology, and moves on to what nanotechnology can achieve.  Then there is the ethical challenge – what is the moral imperative  about making technology that might help increase our lifespans available to all, for example?

Finally, the concern about possible health and environmental implications is perhaps the most controversial.  The problem is that some properties of these tiny particles are unknown, and potentially harmful, and scientists are still trying to determine whether their size affects their toxicity. Scientists worry that the small particles used in nanotechnology could penetrate biological barriers designed to keep out larger particles; also we don’t have guidelines about how much we can safely ingest without harm.  For more on possible harm to human health, click here.

For governments and other authorities that view commercialization of nanotechnology as a way to develop innovative environmental products and create new industries, the concerns present huge challenges.   Is there sufficient understanding or regulation of nanotech based materials to minimize possible harm to us or our environment?  The possible environmental benefits are tantalizing:  for example, water filters with nanometer-scale pores can remove 100% of the bacteria and viruses, another method will remove salt and heavy metals – meaning water from any source can be recycled and made drinkable while also eliminating downstream pollution.  This possibility alone staggers the imagination.

Nanomaterials are perceived as being untested and not well researched.  Environmental groups like Friends of the Earth Europe acknowledge that nanotechnology has the potential to deliver environmental benefits.  Even so, they have called for a moratorium on the release of so-called nanomaterials until new laws are in place to protect the public.

A study done by the Project on Emerging Nanotechnologies found that:  “a lack of information—about nanotechnology-based products, about their possible health and environmental implications, and about the oversight processes designed to manage risks—breeds public mistrust and suspicion….In the absence of balanced information, people are left to speculate about the possible impacts of nanotechnology, and  often draw on analogies to past technologies, many of which may be misleading, such as asbestos, dioxin, Agent Orange, or nuclear power.”

Mike Treder, Executive Director of The Center for Responsible Nanotechnology, said:  “Approached with pessimism, nanotechnology appears far too hazardous to be allowed to progress to anywhere near its full potential. It’s tempting to just say no, to urge that we shut Pandora’s Box and halt further development. It is a challenge of the highest order. The Center for Responsible Nanotechnology (CRN) … has studied these issues in depth for years now, and the clearest thing we can say is that there is no simple solution.  The disruptive and destabilizing implications of advanced nanotechnology must not be underestimated. At the same time, the near miraculous benefits cannot be forfeited. To save our way of life and usher in an even brighter tomorrow, it will be necessary to develop and implement comprehensive, balanced plans for responsible management of this transformative technology.”

Despite all the concerns, the market for nanomaterials has managed to gain an appreciable commercial presence:  actual size is also in dispute because nobody can decide what should be included (i.e., Nano-enabled, nanointermediates, or nanomaterials) but everybody agrees it’s big, with the US as the largest market.



Mercury, fish and fabric

18 08 2010

Once upon a time, mercury was a familiar substance in virtually every home. Often called quicksilver, it was found in thermometers, mirrors and first aid kits (remember Mercurochrome?), but when its many dangers became known, it faded from view and assumed a more hidden role in industrial processes, electronics manufacturing, and fluorescent light bulbs. It is the most toxic non-radioactive element on Earth, and it’s swimming in our oceans. Have you begun to worry about eating fish contaminated with mercury?  Do you avoid some forms of fish, or restrict your portions?  Do you carry around one of those little wallet size crib cards so you know which kinds of fish might be safe and which are not?  Maybe you should, since all fish contain at least trace amounts of methylmercury.

Methylmercury [CH3Hg] is the most toxic form of mercury, and the form which is absorbed by fish.  Methylmercury is created when mercury, in water, is subjected to sulfate-reducing bacteria which metabolize mercury to form methylmercury,  the form that is available to living systems.   In both children and adults, high levels of methylmercury can damage the brain, heart, kidney, lungs and the immune system. More advanced poisoning shows up as mental retardation, cerebral palsy and dementia in adults.  Methylmercury is particularly damaging to developing embryos, which are five to ten times more sensitive than adults. Elemental mercury, Hg(0), the form released from broken thermometers, causes tremors, gingivitis, and excitability when vapors are inhaled over a long period of time. Although it is less toxic than methylmercury, elemental mercury may be found in higher concentrations in environments such as gold mine sites, where it has been used to extract gold.

Mercury is a persistent and bioaccumulative toxin.  “Persistent” toxins are those that, once absorbed by a living system, are not expelled as normal waste, so they build up in the system, or “bioaccumulate”.  Studies have shown that levels of mercury have been building up in various wildlife populations over time:

  • Concentrations of mercury in feathers of fish-eating seabirds from the northeastern Atlantic Ocean have steadily increased for more than a century.
  • In North American sediment cores, sediments deposited since industrialization have mercury concentrations about 3-5 times those found in older sediments.
  • A new report released today by the Ocean Alliance found that sperm whalesfeeding even in the most remote reaches of Earth’s oceans have built up stunningly high levels of toxic and heavy metals.

The findings spell danger not only for marine life but for the millions of humans who depend on seafood.  “You could make a fairly tight argument to say that it is the single greatest health threat that has ever faced the human species,” said biologist Roger Payne, founder and president of Ocean Alliance.

How does the mercury get into the fish?

Although mercury occurs naturally (from volcanoes, forest fires, weathering of rocks and evaporation from soil and water surfaces) the main culprits are considered to be  power plants and other industries that burn coal.  The mercury from smokestacks  not only contaminates nearby water bodies, but also those far from the source.  Once emitted, some mercury can remain circulating in the atmosphere for up to one year.  When the mercury comes into contact with oxidizing chemicals such as ozone, it becomes water soluble.  It is in this form that it is deposited via rain or snow, and finds its way to our waterways.  There microorganisms convert it to methylmercury, the form that is especially toxic to humans and wildlife.  Then it can evaporate and the cycle can continue, distributing mercury wherever rain or snow falls.  This makes mercury pollution a truly global problem.

But since this is a blog about textiles, it’s important to point out that mercury is also used in textile processing.  You may know that mercury was used extensively in felt making operations in the 18th century.  Workers developed trembling (“hatters shakes”), anxiety, and sometimes convulsions and death from breathing in fumes in well insulated workrooms producing felt (inspiration for the phrase, “mad as a hatter”)  In the United States, the use of mercury in the felt industry was banned in 1941.  But did you know that mercury continues to be used  as a component in dyestuffs and as a catalyst in the dyeing process?  Mercury is one of those “heavy metals” that you sometimes see referred to in relation to textile dyes.   So the wastewater from mills which use dyestuffs containing mercury are contributing to mercury in our waters, where it enters fish and shellfish.  Yet another reason to insist that the fabrics you buy are produced at mills where the wastewater is treated before release.

People are exposed to methylmercury almost entirely by eating contaminated fish and wildlife that are at the top of aquatic foodchains.  And as Rachel Carson demonstrated with pesticides, as mercury moves up through the food chain, its toxicity is magnified ten times until, finally, it reaches your dinner plate. 

Prior to 1950, not much was known about mercury poisoning.  But then in Minamata, Japan an extraordinary confluence of events gave us an example of what can happen if a food source is contaminated.

In Minamata, in 1932, the Chisso Corporation began to manufacture acetaldehyde, used to produce plastics.   The plant did not treat its wastewater and dumped it into the bay, where it was converted into methylmercury and entered the food chain.  Minamata residents relied almost exclusively on fish and shellfish for their protein – fish from Minamata Bay.  After WWII, the production of acetaldehyde boomed, and so too did the local economy.  But cats began showing bizarre behavior, sometimes falling into the sea and dying, which residents called “cat suicides”.  Eventually similar behavior began occurring in people too.  People would stumble while walking, or not be able to write or button their buttons, or tremble uncontrollably.  These physiological effects were devastating, and resulted sometimes in partly paralyzed and contorted bodies.   Then children began to be born with this “disease”.  Finally public health services traced the disease to mercury from Chisso.  As Douglas Allchin wrote in The Poisoning of Minamata,

  • The Minamata case is such a vivid example because the town and the bay where the mercury was dumped may be seen as a relatively closed system. The ecological consequences, which are often diffuse and indirect, may be seen as a closed loop: the effects of the effluent led gradually but nevertheless inevitably back to humans. That is, in this exceptional case, one can trace the mercury from its source in Chisso’s production process, through the waste water to the organisms inhabiting the bay, and then to the cats or humans consuming the fish and shellfish. As a microcosm, Minamata illustrates the sometimes fuzzy concept that humans and their environment are inextricably interconnected.”  You can read more about the Minamata disaster here.

Disasters such as the massive release of methyl isocyanate gas from Union Carbide plant’s in Bhopal, India, certainly focus our attention on the adverse human effects and environmental risks of some industry. Yet such “incidents,” like those at Three Mile Island, Chernobyl or the Valdez oil spill can also be dismissed as “accidents” or exceptional single occurences–not as symptomatic of the status of human ecology. One can easily forget the often larger threats posed by low-level but more sustained release of chemicals–the “slow-motion Bhopals.” And one can easily overlook the more difficult, yet far more fundamental issues involving attitudes, lifestyles, and economic and social forces–issues that are so sharply profiled by the history of Minamata.

Today in America, according to PBS, one in six children born every year have been exposed to mercury levels so high that they are potentially at risk for learning disabilities and motor skill impairment and short-term memory loss.

The EPA has published threshold limits for what it considers a safe amount of mercury ingestion – known as a “reference dose”,  which is dependent on body weight.  EPA’s methylmercury reference dose is .1 micrograms per kg of body weight per day.[1]

So exactly how much mercury  does a 45 lb. child  ingest by eating one 6 ounce can of tuna per week, and how does that compare to the EPA’s reference dose? Take a look at the following calculations:


  • Multiply child’s body weight by EPA’s reference dose.
  • Convert 45 pounds to kilograms = 20.45 kilograms
  • 20.45 kilograms x .1 micrograms per kilogram per day

EPA RECOMMENDED LEVEL = 2.05 micrograms per day = 14.35 micrograms per week.


  • Multiply amount of fish by average mercury level for chunk white albacore.
  • Convert 6 ounces to grams = 170 grams 170 grams X .31 ppm  (or micrograms per gram)[2]

MERCURY INGESTED = 52.7 micrograms per gram


  • Divide 52.7 micrograms by 14.35 micrograms = 3.7

By eating 6 ounces of chunk white tuna a week, the child is ingesting almost FOUR times the EPA’s recommended dose., which works to protect the public from mercury poisoning, in conjunction with scientists, medical doctors and consumer advocates wrote to the FDA and EPA in June 2010 urging them to strengthen the Federal fish consumption advisory for mercury and also to do a better job of warning consumers.   “Mercury contamination of seafood is a widespread public health problem and eating fish shouldn’t be a toxic gamble.  The government can and should do more to protect consumers,” said Buffy Martin Tarbox of  According to “The Cove,” the FDA has failed to do their due-diligence in warning the general public of the dangers of mercury, primarily in women and children.  Yet fish consumption advisories can only be an interim solution.  The long-term solution should be the restoration of the chemical integrity of  our ecosystem so we don’t have to refer to our crib sheets each time we want to eat fish.

But there may be a bright light, literally, at the end of this tunnel:  although they don’t know HOW it works, scientists have found that a combination of iron and sunlight destroys almost 90% of methylmercury that enters Alaskan lakes each year.  Read more about that here.

ADDENDUM: In addition to being toxic for humans, tuna, swordfish, and many other fish are caught in ways that are devastating ocean habitats and fisheries. Longline fishing, the destructive fishing method often used to catch tuna and swordfish, kills thousands of endangered sea turtles per year. Many of the fish species listed in mercury calculators are overfished, endangered, or being caught using unsustainable fishing methods. If you would like more information about sustainable seafood, please check out the Monterey Bay Aquarium and  NRDC websites.

[1] This is taken from NOW, a series sponsored by PBS and found at

[2] Average for Chunk White Canned Tuna. Yess, Norma J. “US Food and Drug Administration Survey of Methyl Mercury in Canned Tuna,” Journal of AOAC International, Vol. 76, No. 1, 1993, pp. 36-38.

Fabric and sex

11 08 2010

Whoa, caught your attention, didn’t I?  I’m actually not talking about the company that contacted us to provide organic fabrics for their sexy lingerie, but rather the ways our fabric choices (or rather the chemicals in them) can effect our reproductive systems.  Because many of the chemicals (i.e. chlorine, phthalates, PBDE’s) used in textile processing are those implicated in some alarming statistics,  it’s becoming important to know what’s in your fabrics.

Certain stats are indeed startling:   sperm counts for men in industrialized countries have been declining at a rate of 1% per year – every year since 1934! [1] Infertility affects between 5 – 10% of all couples.  Just two days ago, August 9, NPR’s All Things Considered reported on a new study published in the journal Pediatrics which found that puberty is coming earlier and earlier to young girls.   How much earlier?  In the United States in the early 1800s, breast buds and menarche arrived around ages 13 and 16 respectively. Those changes now come around ages 9 and a half and 12 and a half – sometimes as early as age 7.  Dr. Frank Biro, lead author of this study, was quoted in Time Magazine as speculating on the primary driver behind this shift:

may be overweight and obesity, because estrogen is sequestered in fat tissue. But environmental exposures to chemicals — including pesticides and endocrine-disrupting chemicals (EDCs) — could also play a role.”
And if current trends for the incidence of breast cancer continue at today’s rate, the granddaughter’s of these young girls could face a one in four chance of developing breast cancer, according to the Environmental Working Group.  Testicular and prostate cancers are also both on the rise – in fact, testicular cancer is the most common cancer in men age 15 to 35, and prostate cancer is the most common cancer among all U.S. men.

Dioxins are found in textile dyestuffs, in PCP treated cotton and are created by burning some textiles (incineration is often quoted as an offset for carbon footprint of synthetics) – among the many ways dioxins are used/created during the textile process.  Dioxins affect human health in many ways, and among them is the alteration of hormone levels.  In men, tiny levels of dioxin alter testosterone levels.  Dioxin at 80 parts per trillion in paternal blood causes a significant change in the sex ratio of children.  At this tiny dose, men father nearly twice as many girls as boys.

All this you might already know.  But I recently saw a study which threw a whole new light on these issues.  It was published in the journal Urological Research, and the lead author is Ahmed Shafik.  Dr. Shafik did a study about the effect of different types of textile fabrics on spermatogenesis.    He found that dogs who wore polyester underpants (and I could get really creative here but will spare you) had both a reduction in the number of sperm as well as an increase in abnormal sperm.

First sweathers, then underpants

You’ll be happy to hear that after removal, the sperm counts returned to normal.   Not sure that these results have been replicated (I wasn’t able to find more recent reports of polyester and sperm counts), but it points to another reason – if you’re still looking – for replacements for synthetics.

[1] Swan et al. 2000 –

Using the best materials in the best ways

6 08 2010

The natural fibers used in O Ecotextiles  fabrics are the best in their class: the linen, hemp, wool and cotton are the finest  fiber materials available, and they are processed in  labor intensive, time consuming ways (for instance, the hemp is field retted rather than chemically retted. Chemical retting weakens the fibers as well as contributes to our environmental burden, but its much quicker.)  Natural fibers such as these have always been considered a luxurious choice:  Pima cotton has always been a more luxurious alternative than a synthetic fabric and people have been willing to pay for the characteristics inherent in natural fibers.

The production of high quality natural fibers is as much art as science; at O Ecotextiles we use the best materials in the best ways.

An example of  using the best materials in the best ways is that of Danish master craftsman Hans Wegner, who believed that a chair should be made to last.     His iconic 1949 creation—called the Round Chair or, simply, the Chair—may be the ultimate expression of that philosophy. The clean wood design is stripped to its bare essentials, a sculptural semicircle resting on four tapered legs with a cane or leather seat suspended between them.   The company uses only wood that is about to topple.  “The arms are made from blocks of solid wood.  They’re not bent in any way. That would have been a way to save wood, but you lose something important too.”  A zigzag joint connects the arms with the back. The surface is usually left unvarnished but finished with soap flakes, which makes it easier to maintain and helps it acquire a patina. “With soap, even if there’s a scratch, the wood will rise again”  The use of soap is an aesthetic decision that contributes to the object’s longevity.

This is not an IKEA-style factory, stamping out thousands of products daily. Each unit of the Chair is worked on by at least five craftsmen and takes nearly 12 hours to complete. Only about 200 to 300 are finished per year;  in 58 years a total of 20,000 pieces have been made. The process is a mix of sustainable practices and uncompromising technique.   The chair costs $4,000.

With his love of natural materials and his deep understanding of the need for furniture to be functional as well as beautiful, Hans J. Wegner (1914–) made mid-century Danish design popular on an international scale. He began his career as a cabinetmaker in 1931 and subsequently entered the Copenhagen School of Arts & Crafts. After receiving his architectural degree in 1938, he worked as a designer in Arne Jacobsen and Erik Møller’s architectural office before establishing his own office in 1943.

With more than 500 different chair designs Wegner is the most prolific Danish designer to date. His international breakthrough and greatest sales success came in 1949 when he designed the Round chair. The American magazine Interiors featured the chair on the cover and referred to it as “the world’s most beautiful chair”. The chair rose to stardom when used in the televised presidential debates between Nixon and Kennedy in 1960 and has since been known simply as “The Chair”.

The real beauty of Wegner’s genius must be seen in context with his collaboration with master cabinetmaker Johannes Hansen. The attitude with which Johannes Hansen accepted the young designer’s ideas was the perfect combination between designer and craftsman. Their collaboration went on for many years, and they presented their work at the Cabinetmaker’s show every year from 1941–1966.

Wegner’s design went on to win worldwide recognition through the 1950’s and 1960’s and his furniture, in particular his chairs, are to be found in the permanent collections of the world’s most prestigious museums.

The Chair’s elegant simplicity is a breath of fresh air in our complicated lives.