Ten years ago at the close of the 20th century, people the world over were obsessing about the millennium bug – an unanticipated glitch arising from an earlier technology.  I wonder how clear it was then that, despite this storm in what turned out to be a rather small teacup, the following decade would see unprecedented advances in technology – the mapping of the human genome, social media, nanotechnology, space-tourism, face transplants, hybrid cars, global communications, digital storage, and more.  Looking back, it’s clear that despite a few hiccups, emerging technologies are on a roll – one that’s showing no sign of slowing down.

So what can we expect as we enter the second decade of the twenty first century?  What are the emerging technology trends that are going to be hitting the headlines over the next ten years?

Here’s my list of the top ten technologies I think are worth watching. I’m afraid that, as with all crystal ball gazing, it’s bound to be flawed. Yet as I work on the opportunities and challenges of emerging technologies, these do seem to be areas that are ripe for prime time.

Geoengineering

2009 was the year that geoengineering moved from the fringe to the mainstream.  The idea of engineering the climate on a global scale has been around for a while. But as the penny has dropped that we may be unable – or unwilling – to curb carbon dioxide emissions sufficiently to manage global warming, geoengineering has risen up the political agenda.  My guess is that the next decade will see the debate over geoengineering intensify.  Research will lead to increasingly plausible and economically feasible ways to tinker with the environment.  At the same time, political and social pressure will grow – both to put plans into action (whether multi- or unilaterally), and to limit the use of geoengineering.  The big question is whether globally-coordinated efforts to develop and use the technology in a socially and politically responsible way emerge, or whether we end up with an ugly – and potentially disastrous – free for all.

Smart grids

It may not be that apparent to the average consumer, but the way that electricity is generated, stored and transmitted is under immense strain.  As demand for electrical power grows, a radical rethink of the power grid is needed if we are to get electricity to where it is needed, when it is needed.  And the solution most likely to emerge as the way forward over the next ten years is the Smart Grid.  Smart grids connect producers of electricity to users through an interconnected “intelligent” network.  They allow centralized power stations to be augmented with – and even replaced by – distributed sources such as small-scale wind farms and domestic solar panels.  They route power from where there is excess being generated to where there is excess demand.  And they allow individuals to become providers as well as consumers – feeding power into the grid from home-installed generators, while drawing from the grid when they can’t meet their own demands.  The result is a vastly more efficient, responsive and resilient way of generating and supplying electricity.  As energy demands and limits on greenhouse gas emissions hit conventional electricity grids over the next decade, expect to see smart grids get increasing attention.

Radical materials

Good as they are, most of the materials we use these days are flawed – they don’t work as well as they could.  And usually, the fault lies in how the materials are structured at the atomic and molecular scale.  The past decade has seen some amazing advances in our ability to engineer materials with increasing precision at this scale.  The result is radical materials – materials that far outperform conventional materials in their strength, lightness, conductivity, ability to transmit heat, and a whole host of other characteristics.  Many of these are still at the research stage.  But as demands for high performance materials continue to increase everywhere from medical devices to advanced microprocessors and safe, efficient cars to space flight, radical materials will become increasingly common.  In particular, watch out for products based on carbon nanotubes.  Commercial use of this unique material has had it’s fair share of challenges over the past decade.  But I’m anticipating many of these will be overcome over the next ten years, allowing the material to achieve at least some of it’s long-anticipated promise.

Synthetic biology

Ten years ago, few people had heard of the term “synthetic biology.”  Now, scientists are able to synthesize the genome of a new organism from scratch, and are on the brink of using it to create a living bacteria.  Synthetic biology is about taking control of DNA – the genetic code of life – and engineering it, much in the same way a computer programmer engineers digital code.  It’s arisen in part as the cost of reading and synthesizing DNA sequences has plummeted.  But it is also being driven by scientists and engineers  who believe that living systems can be engineered in the same way as other systems.  In many ways, synthetic biology represents the digitization of biology.  We can now “upload” genetic sequences into a computer, where they can be manipulated like any other digital data.  But we can also “download” them back into reality when we have finished playing with them – creating new genetic code to be inserted into existing – or entirely new – organisms.  This is still expensive, and not as simple as many people would like to believe – we’re really just scratching the surface of the rules that govern how genetic code works.  But as the cost of DNA sequencing and synthesis continues to fall, expect to see the field advance in huge leaps and bounds over the next decade.  I’m not that optimistic about us cracking how the genetic code works in great detail by 2020 – the more we learn at the moment, the more we realize we don’t know.  However, I have no doubt that what we do learn will be enough to ensure synthetic biology is a hot topic over the next decade.  In particular, look out for synthesis of the first artificial organism, the development and use of “BioBricks” – the biological equivalent of electronic components – and the rise of DIY-biotechnology.

Personal genomics

Closely related to the developments underpinning synthetic biology, personal genomics relies on rapid sequencing and interpretation of an individual’s genetic sequence.  The Human Genome Project – completed in 2001 – cost taxpayers around $2.7 billion dollars, and took 13 years to complete.  In 2007, James Watson’s genome was sequenced in 2 months, at a cost of $2 million.  In 2009, Complete Genomics were sequencing personal genomes at less than $5000 a shot.  $1000 personal genomes are now on the cards for the near future – with the possibility of substantially faster/cheaper services by the end of the decade.  What exactly people are going to do with all these data is anyone’s guess at this point – especially as we still have a long way to go before we can make sense of huge sections of the human genome.  Add to this the complication of epigenetics, where external factors lead to changes in how genetic information is decoded which can pass from generation to generation, and and it’s uncertain how far personal genomics will progress over the next decade.  What aren’t in doubt though are the personal, social and economic driving forces behind generating and using this information. These are likely to underpin a growing market for personal genetic information over the next decade – and a growing number of businesses looking to capitalize on the data.

Bio-interfaces

Blurring the boundaries between individuals and machines has long held our fascination. Whether it’s building human-machine hybrids, engineering high performance body parts or interfacing directly with computers, bio-interfaces are the stuff of our wildest dreams and worst nightmares.  Fortunately, we’re still a world away from some of the more extreme imaginings of science fiction – we won’t be constructing the prototype of Star Trek Voyager’s Seven of Nine anytime soon.  But the sophistication with which we can interface with the human body is fast reaching the point where rapid developments should be anticipated.  As a hint of things to come, check out the Luke Arm from Deka (founded by Dean Kamen).  Or Honda’s work on Brain Machine Interfaces.  Over the next decade, the convergence of technologies like Information Technology, nanoscale engineering, biotechnology and neurotechnology are likely to lead to highly sophisticated bio-interfaces.  Expect to see advances in sensors that plug into the brain, prosthetic limbs that are controlled from the brain, and even implants that directly interface with the brain.  My guess is that some of the more radical developments in bio-interfaces will probably occur after 2020.  But a lot of the groundwork will be laid over the next ten years.

Data interfaces

The amount of information available through the internet has exploded over the past decade.  Advances in data storage, transmission and processing have transformed the internet from a geek’s paradise to a supporting pillar of 21st century society.  But while the last ten years have been about access to information, I suspect that the next ten will be dominated by how to make sense of it all.  Without the means to find what we want in this vast sea of information, we are quite literally drowning in data.  And useful as search engines like Google are, they still struggle to separate the meaningful from the meaningless.  As a result, my sense is that over the next decade we will see some significant changes in how we interact with the internet.  We’re already seeing the beginnings of this in websites like Wolfram Alpha that “computes” answers to queries rather than simply returning search hits,  or Microsoft’s Bing, which helps take some of the guesswork out of searches.  Then we have ideas like The Sixth Sense project at the MIT Media Lab, which uses an interactive interface to tap into context-relevant web information.  As devices like phones, cameras, projectors, TV’s, computers, cars, shopping trolleys, you name it, become increasingly integrated and connected, be prepared to see rapid and radical changes in how we interface with and make sense of the web.

Solar power

Is the next decade going to be the one where solar power fulfills its promise?  Quite possibly.  Apart from increased political and social pressure to move towards sustainable energy sources, there are a couple of solar technologies that could well deliver over the next few years.  The first of these is printable solar cells.  They won’t be significantly more efficient than conventional solar cells.  But if the technology can be scaled up and some teething difficulties resolved, they could lead to the cost of solar power plummeting.  The technology is simple in concept – using relatively conventional printing processes and special inks, solar cells could be printed onto cheap, flexible substrates; roll to roll solar panels at a fraction of the cost of conventional silicon-based units.  And this opens the door to widespread use.  The second technology to watch is solar-assisted reactors.  Combining mirror-concentrated solar radiation with some nifty catalysts, it is becoming increasingly feasible to convert sunlight into other forms of energy at extremely high efficiencies.  Imagine being able to split water into hydrogen and oxygen using sunlight and an appropriate catalyst for instance, then recombine them to reclaim the energy on-demand – all at minimal energy loss.  Both of these solar technologies are poised to make a big impact over the next decade.

Nootropics

Drugs that enhance mental ability – increasingly referred to as nootropics – are not new.  But their use patterns are.  Drugs like ritalin, donepezil and modafinil are increasingly being used by students, academics and others to give them a mental edge.  What is startling though is a general sense that this is acceptable practice.  Back in June I ran a straw poll on 2020 Science to gauge attitudes to using nootropics.  Out of 207 respondents, 153 people (74%) either used nootropics, or would consider using them on a regular or occasional basis.  In April 2009, an article in the New Yorker reported on the growing use of “neuroenhancing drugs” to enhance performance. And in an informal poll run by Nature in April 2008, 1 in 5 respondents claimed “they had used drugs for non-medical reasons to stimulate their focus, concentration or memory.” Unlike physical performance-enhancing drugs, it seems that the social rules for nootropics are different.  There are even some who suggest that it is perhaps unethical not to take them – that operating to the best of our mental ability is a personal social obligation.  Of course this leads to a potentially explosive social/technological mix, that won’t be diffused easily.  Over the next ten years, I expect the issue of nootropics will become huge.  There will be questions on whether people should be free to take these drugs, whether the social advantages outweigh the personal advantages, and whether they confer an unfair advantage to users by leading to higher grades, better jobs, more money.  But there’s also the issue of drugs development.  If a strong market for nootropics emerges, there is every chance that new, more effective drugs will follow.  Then the question arises – who gets the “good” stuff, and who suffers as a result?  Whichever way you look at it, the 2010′s are set to be an interesting decade for mind-enhancing substances.

Cosmeceuticals

Cosmetics and pharmaceuticals inhabit very different worlds at the moment.  Pharmaceuticals typically treat or prevent disease, while cosmetics simply make you look better.  But why keep the two separate?  Why not develop products that make you look good by working with your body, rather than simply covering it?  The answer is largely due to regulation – drugs have to be put through a far more stringent set of checks and balances that cosmetics before entering the market, and rightly so.  But beyond this, there is enormous commercial potential in combining the two, especially as new science is paving the way for externally applied substances to do more than just beautify.  Products that blur the line are already available – in the US for instance, sunscreens and anti dandruff shampoos are considered drugs.  And the cosmetics industry regularly use the term “cosmeceutical” to describe products with medicinal or drug-like properties.  Yet with advances in synthetic chemistry and nanoscale engineering, it’s becoming increasingly possible to develop products that do more than just lead to “cosmetic” changes.  Imagine products that make you look younger, fresher, more beautiful, by changing your body rather than just covering up flaws and imperfections.  It’s a cosmetics company’s dream – one shared by many of their customers I suspect.  The dam that’s preventing many such products at the moment is regulation.  But if the pressure becomes too great – and there’s a fair chance it will over the next ten years – this dam is likely to burst.  And when it does, cosmeceuticals are going to hit the scene big-time.

So those are my ten emerging technology trends to watch over the next decade.  But what happened to nanotechnology, and what other technologies were on my shortlist?

Nanotech has been a dominant emerging technology over the past ten years.  But in many ways, it’s a fake.  Advances in the science of understanding and manipulating matter at the nanoscale are indisputable, as are the early technology outcomes of this science.  But nanotechnology is really just a convenient shorthand for a whole raft of emerging technologies that span semiconductors to sunscreens, and often share nothing more than an engineered structure that is somewhere between 1 – 100 nanometers in scale.  So rather than focus on nanotech, I decided to look at specific technologies which I think will make a significant impact over the next decade.  Perhaps not surprisingly though, many of them depend in some way on working with matter at nanometer scales.

In terms of the emerging technologies shortlist, it was tough to whittle this down to ten trends. My initial list included batteries, decentralized computing, biofuels, stem cells, cloning, artificial intelligence, robotics, low earth orbit flights, clean tech, neuroscience and memristors – there are many others that no doubt could and should have been on it.  Some of these I felt were likely to reach their prime sometime after the next decade.  Others I felt didn’t have as much potential to shake things up and make headlines as the ones I chose.  But this was a highly subjective and personal process.  I’m sure if someone else were writing this, the top ten list would be different.

And one final word.  Many of the technologies I’ve highlighted reflect an overarching trend: convergence.  Although not a technology in itself, synergistic convergence between different areas of knowledge and expertise will likely dominate emerging technology trends over the next decade.  Which means that confident as I am in my predictions, the chances of something completely different, unusual and amazing happening are…  pretty high!

Update, 12/27/09  Something’s been bugging me, and I’ve just realized what it is – in my original list of ten, I had smart drugs, but in the editing process they somehow got left by the wayside!  As I don’t want to go back and change the ten emerging technology trends I ended up posting, they will have to be a bonus.  As it is, drug delivery timelines are so long that I’m not sure how many smart drugs will hit the market before 2020.  But when they do, they will surely mark a turning point in therapeutics.  These are drugs that are programmed to behave in various ways.  The simplest are designed to accumulate around disease sites, then destroy the disease on command – gold shell nanoparticles fit the bill here, preferentially accumulating around tumors then destroying them by heating up when irradiated with infrared radiation.  More sophisticated smart drugs are in the pipeline though that are designed to seek out diseased cells, provide local diagnostics, then release therapeutic agents on demand.  The result is targeted disease treatment that leads to significantly greater efficacy at substantially lower doses.  Whether or not these make a significant impact over the next decade, they are definitely a technology to watch.

Update 12/29/09  Which emerging technologies do you thing will trend over the next decade?  Join the discussion on the 2020 Science Facebook page.

By George Kimbrell, International Center for Technology Assessment, and the Center for Food Safety

A guest blog in the Alternative Perspectives on Technology Innovation series

Andrew asked us to write about “how technological innovation should contribute to life in the 21^st century.”  Technological innovation is often blindly referred to as “progress.”  The question is — progress towards what?

We live in the age of technology.  In past generations, most people spent the majority of their time in nature, and then in later years more often in social settings.  In the modern world, most of us spend an ever-increasing amount of time in an interconnected web of machines.  I’d like to say I’m writing this on a riverside, but unfortunately I’m not – I’m in my office typing on my laptop, with my email open on a different web browser.

What currently drives this technological innovation, this technological bubble that defines our age?  In modern society, self-interest, greater productivity, greater consumption, the laws of supply and demand and the commoditization of the world are all drivers.  This economic system, which has now succeeded in global hegemony, dictates all our social interactions. Far from being a natural state of being, it is of course only as old as the United States (Adam Smith’s Wealth of Nations was published in 1776) and not based on any natural law. In early societies, the market system was never the method by which basic societal problems were addressed; rather the marketplace was delegated only a limited role by our ancestors compared to their cultural and religious beliefs and social patterns.  Nature (not to mention labor), although treated as such, is not a commodity. Nature does not respond to supply and demand. The old-growth forests of the Pacific Northwest will not speed up their growth rate to address increased demand.  More fundamentally, the natural world has intrinsic, incalculable value above and far beyond “market values”.  Even the U.S. Endangered Species Act (ESA) recognizes this truth, in that it prohibits the extermination of species no matter how lucrative the activity  that is causing the killing.

Not only are the current dominant economic systems and their intertwined technological systems at odds with the ecological cycles of the natural world, but they are also actively and quickly eviscerating the planet.  We are exponentially reducing the earth’s capacities in every natural realm: land, air, water, and everything in between, through ozone depletion, acid rain, species extinction, deforestation, and desertification.  By commodifying nature to match our own systems we are threatening the planets’ survival and our own.  Global warming illustrates this conclusion best: Our industrial technologies have created the first global environmental crisis in human history.

We now face what is known as the technological dilemma—the “developed” portion of the world’s population has become dependent on the technological environment. Yet the same technologies that support life for the richest part of human population are threatening the very viability of life on Earth.  Even former President George W. Bush said we are “addicted to oil.”  And this addiction to these unhealthy systems of production is destroying our world.  To paraphrase and apply the wisdom of Rowlf the Dog from the Muppets to market-based mass consumerism: we can’t live with our technologies, and we can’t imagine living without them.

These are not new revelations.  And there are really only two options.  Forty years ago, writers and leaders began urging that we institute “appropriate technologies” in sync with the cycles of nature, rather than the mega-global-techno-systems causing planetary and human peril.  Attorneys and policymakers have succeeded in passing and utilizing laws that would limit the impacts of capital and industrial systems, like the ESA.  Scientists began to develop more holistic visions of their vocations.  This approach/option is a step toward addressing economic development within the context of rather than at the expense of our global environment and the society which depends upon it.

But others too have come to the conclusion that our current technology is not compatible with life.  They have foreseen the growing conflict between globalization, mass consumption, and the laws of nature.  However, their solution to the dilemma is very different.  Rather than change our economics and technology to better comport with the needs of living things, corporations and governments began to engineer life itself to better accommodate the market system and the technologies upon which it is predicated.  Ignoring the constraints of the natural world, living systems are to be remade, engineered at the genetic and molecular level to further the necessities of the technological age.

What’s the result of this worldview?  You probably see where this is going.  Genetic engineering, or recombinant DNA technology, is seen as the tool by which we can alter life at the genetic level to better fit industrial production systems and become a technological commodity.  Cloning is seen as the tool by which we can emulate the factory model of identical production for life forms.  Rather than redesigning industrial agriculture to fit the animal’s natural behavior, we are redesigning the animal to fit industrial agriculture.  Because patent control spurred production for products, we must now patent plants, animals, and human genes and cells.  Nanotechnology is a means by which we can control and manipulate matter at the atomic and molecular level to enhance industrial processes.  Lastly, synthetic biology is a means by which we combine several of these tools to create and design entirely new life forms to perform our industrial tasks. Even Dr. Frankenstein was cautious enough to not make his creature a mate; “synthetic biologists,” on the other hand, want their creatures to reproduce before systems are in place to control them.

Got environmental problems? Global warming does not to be addressed by stopping harmful greenhouse gas emissions and putting in place strictures to address systemic problems; instead, we should geo-engineer the planet to ameliorate the problem, or genetically engineer plants to be more drought- tolerant or trees to grow faster.  Chemical pollution causing environmental and health hazards? We do not need to reduce our use of harmful pesticides; instead, we should engineer production plants to be immune to them.  Pigs and chickens not amenable to horrific close-confinement factory farming?  Don’t encourage organic and humane farming and change the systems by making industrial agriculture internalize the true costs of its production; instead,  genetically alter the animals to withstand extreme confinement and diseases that proliferate therein.  Wild salmon runs dying out?  Don’t remove the dams and stop the pollution, farm them and genetically re-engineer them to grow faster in crowded, polluted ponds.

So where does that leave us?  Well, first, we must recognize and address the underlying philosophy and economy that drives and controls technological innovation. An order of magnitude in change is required; we must institute a paradigm-shift to a system of governance and life that is based on coexistence with and benefit to natural systems: An earth-centered system.  As Thomas Berry explains in The Dream of Earth, we must move from the technological age to the ecological age.  We must begin treating ourselves and the natural world as part of an interconnected web; stop thinking in straight lines and start thinking in circles.  “Progress” must include the natural as well as the human world, encouraging mutually enhancing human-earth relationships.  Human technologies should function in an integral relationship with earth technologies, not in a despotic manner.  Nature, over hundreds of millions of years and through an infinite number of experiments, worked out ecosystems that were already flourishing abundantly when we came to exist.  How can technological innovation help us determine how we can best be present in this context?  Modern society must treat life and the natural world as the spiritual force it is.  There must be a mystique of rivers if we are ever going to restore the purity of our rivers.  This is not a new idea, it is actually the oldest.  Is this an idealized vision? Perhaps, but it’s a considerably less naive world vision that that which claims we can sustain our current industrial system.

Can technological innovation help us get there?  If it changes the course current path we’re going down, if it helps stop the bleeding.  If it breaks away from being driven by corporate profits, and instead helps spread knowledge, wisdom, and awareness.  If it helps us flesh out and establish an earth-centered system to replace the current oppressive paradigm.  We must evolve our technological systems so that they are democratic and responsive to us, that we are responsible for them, and so that they comport with nature and with life forms on the earth.  We can dust off the old ways and make them the new again, making them more seductive and more logical than our current destructive ways. Only with these changes will technological innovation properly serve the planet and enhance, as well as extend, a meaningful human experience.

___________________

George A. Kimbrell is a staff attorney for the nonprofit Center for Food Safety (CFS) and its parent organization International Center for Technology Assessment (ICTA), based in San Francisco, California.  He practices environmental and administrative law with a focus on legal and policy issues related to new and emerging technologies.  For ICTA, he works on matters involving nanotechnology, biotechnology and climate change technologies.  For CFS, he covers genetically engineered food and crops, organic standards, factory farming and aquaculture.

Mr. Kimbrell received his J.D. magna cum laude from Lewis and Clark Law School and has a B.A. from the College of William and Mary.  Prior to joining ICTA and CFS, he completed a clerkship on the United States Court of Appeals for the Ninth Circuit.

I do not here officially represent my organizations or clients.  The views discussed herein owe much to the ideas and writings of others.  For more detailed discussion of many of these issues, please see, inter alia, Andrew Kimbrell, Salmon Economics (and other lessons), Twenty-Third Annual E.F. Schumacher Lectures, Stockbridge, Mass. (Oct 2003).

It feels good to be ahead of the curve sometimes. About this time last year, I was slaving away painting my roof white – much to the bemusement of my Northern Virginia neighbors and friends. So I couldn’t help feeling just a little smug this morning as I read that US Secretary of Energy Steve Chu is also a great fan of roof-painting to combat global warming…

Perhaps the whitest roof in Northern Virginia

According to The Independent newspaper,

Steven Chu, the US Secretary of Energy and a Nobel prize-winning scientist, said yesterday that making roofs and pavements white or light-coloured would help to reduce global warming by both conserving energy and reflecting sunlight back into space. It would, he said, be the equivalent of taking all the cars in the world off the road for 11 years.

Speaking in London prior to a meeting of some of the world’s best minds on how to combat climate change, Dr Chu said the simple act of painting roofs white could have a dramatic impact on the amount of energy used to keep buildings comfortable, as well as directly offsetting global warming by increasing the reflectivity of the Earth.

A couple of years ago, we moved into a house with no loft space – just a few inches of paltry insulation between the standard-issue dark-shingled roof and our main living area.  And in the summer, things got hot.  Really hot.  The solution seemed obvious – paint the shingles white, to reflect the sunlight and prevent any unnecessary warming.

Now painting your roof is not something that East Coast folks seem to go in for, and it took a year to pluck up the courage and act on my convictions.  But come the warm weather last summer I decided that enough was enough.  So I purchased vast quantities of Hy-Tec Thermal Solutions Insul Cool-Coat white paint, power-washed the roof (an adventure in itself), and spent three back-breaking days painting the shingles white.

I’d like to report that, in a controlled comparison, the impact of the paint was immediate and stunning.  Unfortunately the AC unit packed in half way through the painting exercise so a strict A/B comparison was out of the question – just my luck!  Nevertheless, the qualitative and quite unscientific results of the new paint were pretty impressive – the upstairs rooms in the house underwent a figurative transformation from fiery furnace to cool cave!  More significantly, the temperature under the painted shingles was some 30 degrees Farenheit lower than that under the unpainted shingles on the garage under the mid-day sun – suggesting that an awful lot of the sun’s heat was no longer infiltrating the house.

The whole point of the exercise was to reflect as much of the sun’s heat as possible, rather than it being absorbed by the previously dark roof and subsequently having to be pumped out (at considerable expense) by the air conditioning.  The paint I used also acts as an insulator.  It’s crammed full of hollow microspheres that inhibit the flow of heat through it, as well as reflect back the sun’s light.   I think it worked – certainly the new AC system seems to be under less strain in the summer, and the house feels significantly more comfortable.  But by increasing the roof’s albedo, I was also able to do my (admittedly small) bit to counter global warming by reflecting away more of the sun’s energy.

It’s not an idea that has had much traction around here – yet.  I suspect the only way I’ve got away with it is by exuding an aura of eccentricity – at least the neighbors could whisper “well, he’s British you know…”  But now that Steve Chu has enlightened the world to the benefits of roof-painting, who knows where we’ll be in 12 month’s time – forget about going green, maybe the “white revolution” will come to McLean Virginia – and I will be able to proudly say I was there first!

Of course, regular roofs are probably trickier to paint than ours, which has a reasonably low pitch.  And I suspect not everyone will appreciate the aesthetic of white shingles or (shock horror) white painted slate.  But it has to be said, as a cheap and achievable solution to a significant problem, roof-painting has a lot to recommend it – a little bit of personal geoengineering to make the earth a better place!

It just took a savvy Nobel prize-winner to let the cat out of the bag!

]]> http://2020science.org/2009/05/27/steve-chus-white-revolution/feed/ 25 http://2020science.org/2009/05/26/nanotechnology-primer/ http://2020science.org/2009/05/26/nanotechnology-primer/#comments Tue, 26 May 2009 13:08:56 +0000 Andrew Maynard http://2020science.org/?p=1633

Back in April, the folks at the PBS station THIRTEEN asked me to answer 13 questions on nanotechnology and the environment for their website feature Green Thirteen.   The questions ended up covering most of nanotechnology – what it is, what it’s good for, what the downsides might be, and how we might overcome potential problems to use it effectively.  With this in mind, I thought it worth posting the Q&A here as a brief nanotechnology primer…

1. What is nanotechnology?

The chemist and Nobel prize winner Richard Smalley described nanotechnology as “the art and science of making stuff that does stuff at the nanometer scale.”

Nanotechnology involves working with materials at an incredibly fine scale—around the size of the atoms and molecules that they are made of.  But the aim is to achieve something new and useful by working at this scale.

Working at the nanometer scale—where one nanometer is a mere one billionth of a meter long—it becomes possible to tap into some unique properties of matter.  Many of these properties only become apparent when small clumps of atoms and molecules are carefully constructed and used as the building blocks of larger structures.  For instance, some materials can be used in new ways when they are engineered at the nanoscale, simply because they are more versatile than non-nanoscale materials.  Other materials behave in strange new ways that enable innovative uses.  Gold, for example, becomes a highly reactive, red-colored metal when formed into nanometer-size particles.  And working at the nanoscale allows highly sophisticated new materials to be engineered that would be impossible to produce using conventional technologies—everything from super-strong materials to the next generation of computer chips to targeted drugs.

2. What are the benefits of nanotech?

The benefits of nanotechnology are incredibly broad, but generally involve making existing technologies work better, or enabling the development of  new technologies.

Many people see nanotechnology as a tool kit that allows scientists and engineers to do new things, whether they are chemists, physicists, biologists, or working in a hundred and one other fields.  In many cases, the things we use everyday don’t work as well as they could because we haven’t been able to control their structure precisely at the finest level.  But nanotechnology is changing this.  For instance, a growing number of consumer products are being improved through the use of simple nanotechnology-based applications:  Sunscreens that go on clear, but protect against harmful UV radiation; clothing that repels stains; socks that prevent the buildup of odor-causing bacteria; tennis racquets that are stronger and lighter; MP3 players that are smaller while holding more songs; even foods that are supposedly better because they have been engineered at the nanometer scale.

But these consumer products are only the tip of the nanotechnology iceberg.  Because the technology enables other technologies to work better, it has the potential to help address some of the biggest challenges facing us.  These include combating climate change, generating renewable energy, controlling pollution, ensuring access to clean water, and developing highly effective medical treatments.

As nanotechnology is used to make better products and address serious challenges, it is expected to generate jobs and money.  Some estimates put the possible market value of products that depend in some way on nanotechnology as being worth over $3 trillion dollars within the next five years.  While the significance estimates like these are sometimes hard to evaluate, there is little doubt that the “nanotechnology tool kit” will play a major role in underpinning future technological and economic development.

3. How does nanotech improve existing technologies?

Sophisticated as they might seem, many existing technologies are akin to trying to make fine jewelry while wearing boxing gloves.  Nanotechnology is the equivalent of removing the gloves—it gives us the ability to fine tune how materials and products are put together at the finest level.  For example, consider the integrated circuits at the heart of modern computers.  The power of these circuits is limited by how many components can be squeezed onto a single chip.  But it is also limited by how fast the heat generated by the electrons coursing through the components can be removed.  Nanotechnology is enabling components—individual transistors and connectors—to be shrunk to the nanoscale, allowing many more of them to be packed onto single chips.  But it is also improving the materials used to transmit heat away from these components, ensuring they don’t over-heat and stop working.

Sunscreens are another example of where nanotechnology improves an existing technology.  Ten to fifteen years go there were two options to making a sunscreen.  You could either use chemicals that are absorbed into the skin, and protect against harmful UV radiation from the sun.  Or you could use particles of materials like titanium dioxide—the same material used to make paint and some foods a brilliant white—to coat the skin and reflect the harmful radiation.  The particles were generally more effective at protecting the user and had the advantage that they lay on top of the skin rather than being absorbed into it—but they left a pasty white residue on the skin that was cosmetically unattractive.  Nanotechnology has since removed this disadvantage.  But using nanometer-scale particles of materials like titanium dioxide and zinc oxide, manufacturers have developed sunscreens that are transparent to visible light while still reflecting UV radiation—and that don’t rely on chemicals that are absorbed into the skin.  The result is highly effective products that are also cosmetically acceptable.

Almost any technology that can be thought of which relies on physical materials can be improved using nanotechnology—simply because nanotechnology provides increased control over the atoms and molecules that make up any material and determine its properties.  However, the economic, social and personal advantages of the improvements will not always outweigh the time, effort and resources needed to make them happen.

4. What kinds of industries are involved? How and where are nanomaterials made?

There are many types of industries involved in nanotechnology, ranging from small startup companies to major multinational corporations.  The types of materials being made are also very diverse.  The NanoMetro map published by the Project on Emerging Nanotechnologies gives a feel for the range and location of nanotech businesses in the US, although it probably doesn’t capture everything that is happening.  The map identifies industries using nanotechnology in the broad areas of electronics, energy and environmental applications, imaging and microscopy, tools and instruments, medicine and health, and materials.  One important point here is that nanotechnology is as much about the tools needed to see and manipulate matter at the nanometer scale—electron microscopes and scanning force microscopes for instance—as it is about creating and using new materials.

Many nanotechnology applications rely on nanomaterials—materials that have been engineered with nanometer-scale structures.  A lot of the nanomaterials currently in use are simply nanometer-scale forms of materials that have been used for many years—such as the titanium dioxide nanoparticles used in sunscreens and elsewhere.  As a result, it is common to find companies with experience developing chemicals and materials using more traditional methods beginning to develop nanomaterials.  At the same time, there are a number of smaller companies that are developing increasingly sophisticated and unique nanomaterials.  In many cases, these are being spun out of University-based nanotechnology research.

Approached to making nanomaterials are as diverse as the materials themselves.  Some of the simplest nanomaterials are made by reacting chemicals together, either in a liquid—to produce suspensions of nanoparticles—or in a gas, essentially burning materials in a controlled manner to produce nanometer-scale particles.  These are then collected, purified, and further processed before being added to products.  At the other end of the spectrum, researchers are modifying viruses, and re-programming them to build nanomaterials.  Recent research has led to new batteries that are based on virus-constructed electrodes.  In between, there are many different ways of engineering matter to form nanostructured materials that can be used to add value to products.

5. What kinds of nanomaterials are appearing in consumer goods?

Most nanotechnology-enabled consumer products currently available rely on relatively simple nanomaterials.  A survey by the Project on Emerging Nanotechnologies indicates that silver nanoparticles are one of the most the dominant nanomaterials currently in use, appearing as an antimicrobial agent in everything from clothing to cooking utensils.  Carbon nanotubes—a unique form of carbon with unusual mechanical and electrical properties—is also appearing in a number of products, predominantly in sporting goods as a way to make them stronger and lighter.  Nanoparticles of zinc oxide and titanium dioxide are widely used in sunscreens and cosmetics, while silica nanoparticles are also being used in a number of products.  In addition there are a number of products using “soft” nanomaterials, which rapidly fall apart when they have done their job.  For instance, some cosmetics use nanometer scale liposomes—very small capsules containing specific materials—to deliver nutrients and other ingredients to the outer layers of the skin.  These disintegrate when they reach their destination, delivering the encapsulated material to where it is needed.

With the exception of carbon nanotubes, these and other nanomaterials being used in consumer products tend to be nanostructured versions of materials that have been used for some time.  However, over the next few years it is likely that increasingly sophisticated and complex nanomaterials will find uses in consumer products.

6. What are the negatives of nanotech?

Like any technology, nanotechnology has its plusses and minuses.  These will generally be specific to different uses of nanotechnology.  For instance, the potential downsides of a nanotechnology-enabled memory chip in an MP3 player will be very different from using nanoparticles in food.

Because of the new and unusual behavior of many engineered nanomaterials, questions have been raised about their safety.  If something can be used in new ways, get to new places, or has new and unusual physical and chemical properties, it is reasonable to ask whether these might also lead to new ways of causing harm—either to humans or the environment.  Evidence to date is sketchy, but it does suggest that some nanomaterials might cause harm in unexpected ways if exposure occurs.  For some nanomaterials, their potential to cause harm will be negligible.  In other situations, more care will need to be taken to ensure safe use—a lot depends on whether exposure is likely, and how toxic the material is.  Common sense and current knowledge go a long way to reducing possible risks.  But more work is still needed to determine the best ways of using these new materials as safely as possible.

Other concerns about nanotechnology are more social and ethical in nature.  Will nanotechnology lead to personal rights being infringed—perhaps through ubiquitous surveillance?  Who will benefit from these emerging technologies, and who will pay the price?  At what point should the use of nanotechnology in enhancing human abilities be questioned?  These and similar questions are not unique to nanotechnology.  But they are an important component of the debate surrounding its development and use.

7. Are there any health side-effects associate with nanotechnology? (e.g. carbon nanotubes causing lung cancer, unexpected in-vivo reactions)

Nanotechnology in and of itself does not lead to health impacts, simply because it is a toolbox of different techniques rather than one specific technology.  However, some uses of nanotechnology could affect people’s health if used inappropriately.

For a material to cause harm to humans, it must first get into the body.  Once there, it’s toxicity will determine how severe any response is.  A high exposure to a low toxicity material (and many nanomaterials will have a low toxicity) may result in a negligible impact.  On the other hand, a low exposure to a highly toxic material could cause a lot of damage.

Two materials that have been researched quite a bit are titanium dioxide nanoparticles, and carbon nanotubes.  In both cases, the materials have been studied in cell cultures and in animals but not humans, and so estimating the toxicity of the materials to people is a little difficult.

Research has shown that inhaled titanium dioxide nanoparticles are more toxic than larger particles of the same substance.  In this case, size makes a difference it seems.  However, as titanium dioxide has a very low toxicity to begin with, the nanoparticles—even though they appear to be more toxic—still seem to be reasonably safe.

Carbon nanotubes appear to be harmful if inhaled, but the harm seems to depend on the type of nanotubes—and there are many types of carbon nanotubes.  Recent research has indicated that long, straight, stiff carbon nanotubes that look like asbestos fibers under the microscope, could be as harmful as asbestos if inhaled.  However, many types of carbon nanotubes don’t have the right shape for this to be a serious concern.  Other research has shown that tangled clumps of carbon nanotubes could also harm the lungs if inhaled, although it unclear how much material is needed for harm to occur.

In both these cases, the critical factor is exposure.  If exposures are low—either while making the materials or using products containing them—risks of health effects will also be low.  The good news is that it seems exposure to carbon nanotubes probably will be low—this is a material that doesn’t readily become airborne as fine fibers.  However, more research is needed to work out how low an exposure is low enough.

8. What kinds of threats to the environment might nanotech pose? (e.g.metal oxide nanoparticle toxicity to fish and frogs)

It’s not clear how harmful different nanomaterials will be if they get out into the environment, although it is clear that some nanomaterials will be more harmful than others.  Important questions that still needs answers include how much material is likely to be release, and from where; whether this material is in the form of nanoparticles, or whether it clumps up into larger particles; how far it is transported, and whether it changes as it moves through the environment; where it accumulates, how long it lasts in the environment, which plants and animals will become exposed, and what the impacts might be.

The good news is that nanoparticles from sources like fires and volcanic eruptions have been ubiquitous in the environment as long as living organisms have been around, and so they have evolved over time to deal with them.  That said, no-one is quite sure how the environment will respond to novel engineered nanomaterials—especially precisely engineered nanoparticles.

One particular potential threat that has already been raised concerns the use of nano-silver in products.  Silver is very effective at killing microbes, which is why it is being used in an increasing number of products.  But it is also highly toxic to a number of organisms as well as microbes.  What is not clear at present is what the impact of silver nanoparticles washed out of products and into the environment might be.  The amounts used may be low enough for the impact to be negligible—or they may not.  It’s a question that can’t be answered well without more information on how much nano-silver is being used, where it is being used, and the likely impacts on the environment if it is released.

9. Who regulates nanotechnology products?

There is no one agency or organization that regulates nanotechnology products.  Rather, they are regulated according to the type of product.  For instance, the US Food and Drug Administration (FDA) is responsible for drugs, food additives and cosmetics that contain engineered nanomaterials.  The US Consumer Protection Safety Commission covers consumer product safety.  The US Department of Agriculture covers food safety—except where FDA has jurisdiction.  And the US Environmental Protection Agency is responsible for chemicals and pesticides.  Each part of this patchwork of regulations and regulatory agencies has different levels of regulatory authority when it comes to nanotechnology products.

10. How much is still not known about the safety of nanotech products, and what needs to be done to fill in the gaps?

From a scientific perspective, there is still a tremendous amount that we don’t know about how to develop and use nanotechnology products safely.  Specific research question that need answers have been raised by a number of organizations, including the Project on Emerging Nanotechnologies and the US government National Nanotechnology Initiative.  There is broad agreement that if nanotechnology is to succeed—and succeed safely—there needs to be a major strategic research program that identifies and fills the outstanding research gaps.  This will require a clear set of goals and objectives, additional research funding, and greater coordination between the organizations that fund research, and those that use the information to ensure material and product safety.

That said, we are not starting out with a blank slate when it comes to using nanotechnology products safely.  Knowledge from other materials can be used to reduce potential risks in many cases, and existing regulations can be applied to nanomaterials—although their implementation may be less than perfect.  However, strategic research will be essential to underpin the long-term safety of increasingly sophisticated nanotechnology-based materials and products.

11. What kinds of recycling challenges are there for nanotech materials? What about nanolitter?

Recycling nanotechnology products presents a number of challenges.  First, there is the problem of stuff that isn’t recycled, either because no-one thinks about it, or because including nanomaterials in a product makes recycling difficult.  This leads to the possibility of nanomaterials being released into the environment as products are disposed of in landfills and slowly degrade, or are incinerated.

Where nanotechnology products are recycled there are two challenges:  Is it worth attempting to extract and reuse the nanotechnology components of the products, and how might this be done; and does the inclusion of a nanomaterial in a product make conventional recycling harder?  To illustrate this second point, imagine nanoparticles of some substance were added to plastic bottles to make them perform better, but that these nanoparticles interfered with the quality of material recycled from conventional plastic bottles.  Would it be better to separate out the nano and non-nano bottles, and how would that be achieved in practice.  The first challenge is perhaps a little easier to address, as it is unlikely that nanomaterials could be recycled from nanotechnology products in a useable state.  Rather, it is more likely that the substances forming the nanomaterials—the silver in nano-silver socks for example—would be reclaimed and used to form new nanomaterials.

12. What are some of the future uses for nanotechnology? How likely is a nano-fabricator?

The next few decades will most likely see some tremendous advances that are based in part on controlling matter at the nanometer scale.  These could well include new forms of generating and storing energy; lighter stronger materials; targeted cancer treatments; treatments for degenerative diseases; efficient ways to purify water; faster more powerful computers; computers that run on light, not electricity; biological organisms that are programmed to make new materials and devices; metamaterials that channel light in highly unusual ways.  We will definitely see a shift from the rather simple nanomaterials being used today to increasingly complex multifunctional nanomaterials.  And associated with this will be an increasingly sophisticated suite of instruments for observing and manipulating the world at the nanoscale.

Based on current research, there will further advances in developing new molecules and nanoscale systems that mimic or reflect what happens in biology (biology, after all, operates very effectively at the nanoscale).  These will move us closer to building new materials and devices molecule by molecule.  But the end result will be much closer to conventional chemistry or biology than the “nano-fabricator”—a speculative machine that can construct complex products out of their constituent atoms, much like the replicators of Star Trek.

13. How can we prevent future problems with nanotechnology? (e.g. grey goo)

Nanotechnology will come with its own set of problems—just as every technology preceding it has.  The trick here will be to have the foresight to spot the problems before they get too large and to navigate a course around them.  This is a tough task.  It will require strategic research to address plausible issues, and ways of translating the results of this research into proactive action.

Even with such an approach, there will be mis-steps.  But hopefully, with the right strategies in place, corrective action will be able to taken fast enough to prevent either major human health or environmental impacts, or the hopes of nanotechnology to address critical challenges being dashed.

In the long term, there may be challenges that are outside our current ability to comprehend the potential dangers, and how to avoid them.  Not self-replicating nanobots perhaps—the so-called “grey goo” that is more science fantasy than science fact—but other technological breakthroughs that take us places unimaginable a few years ago.  The only way to deal with such challenges is to develop institutions that are sufficiently fleet footed and forward-looking to respond to the challenges as they come over the horizon.

The one thing we cannot afford to do is to stick our heads in the sand and ignore potential of nanotechnology to do great good and possibly great harm.

These questions and answers first appeared in their original form at THIRTEEN.ORG on April 28 2009

Reading yesterday’s New York Times, it seems China could well be poised to leapfrog the West in advanced battery technology (China Vies to Be World’s Leader in Electric Cars). According to the article, Chinese leaders have adopted a plan aimed at turning the country into one of the leading producers of hybrid and all-electric vehicles within three years, and making it the world leader in electric cars and buses after that.

If they deliver the goods, the economic ramifications will be significant.  But then so will the resulting breakthroughs in battery technology.

Despite our ever-increasing addiction to battery-powered gizmos, current technologies are seriously limited.  My laptop and cell-phone (and this morning, my e-book) constantly seem to die at most inopportune moments.  And remembering to recharge the 1001 things in my life that depend on batteries (while working out which recharger goes with which device) is a time-suck I could easily live without.

No question, personal electronics are desperately in need of a major battery upgrade.

But that’s small fry compared to the challenges of developing usable batteries for power-hungry cars.

The problem is, it’s hard to get electricity into batteries fast; hard to get it out again; and once you’ve got a lot of it in there, hard to prevent the battery having a melt-down—remember the stories of igniting/exploding PC batteries?  These are tractable problems for the small stuff—cell phones and the like—but they present enormous obstacles to scaling up batteries large enough to power cars.

Yet developing battery-powered cars makes a lot of sense… It reduces reliance on highly-refined fossil fuels.  It has the potential to even out electricity demands—essentially using batteries as an energy-buffer.  It enables Prius-like energy-recovery while driving. And it relocates a harmful source of pollution (tailpipe emissions) to where it can be better managed—at the power station.

The good news is that emerging technologies like nanotechnology are providing solutions to at least some of the challenges being faced in developing advanced batteries.  Lithium ion batteries in particular are benefiting from electrodes engineered with nanometer-scale structures, which decrease charging time and increase power output, while improving battery safety.  Companies like A123 and Altairnano are already exploiting nanotechnology-based developments in advanced batteries.  And anecdotally, experts suspect that the performance of most high-end laptop batteries already depend on the use of carbon nanotubes in the electrodes.

There’s still some way to go before this technology matures to the point where electric cars make sense on a grand scale.  But that day is coming.  And by all accounts China will be in the lead when it does.  China is already a major player in the field of nanotechnology (see last week’s piece by Tom Mackenzie in The Guardian for instance), and has the capacity to focus research and development resources where they are most likely to deliver the goods.

The end result probably doesn’t bode well for an ailing US car industry which is still struggling to readjust to a world where smaller, lighter, greener are the order of the day (even the much-touted Chevy Volt still looks like old ideas dressed in new technology).  But a push by China to develop technologically and economically viable electric cars could stimulate world-wide development of battery technologies that leads to a reduced dependence on fossil fuels, and a smaller overall environmental footprint.

That would certainly be good news.

And as a spin-off, there’s a chance that we might finally get batteries for our laptops, cell phones and e-books that don’t die when we need the most.  Now that would be progress indeed!

Footnotes

While writing this, there was some discussion on the NYT article and batteries in general on Twitter.  I particularly wanted to acknowledge helpful comments and links from @joergheber (esp. on wireless power transfer), @quantum_tunnel (re-engineering batteries) and @crc2008 (for the link to the Lightning Car Company) – thanks guys.

Part 1 of a series on rethinking science and technology for the 21st century

We live in a crowded, science and technology-dependent word.  And things aren’t getting any better!  The global population is currently around 6.8 billion.  Over the next four years it’s projected to grow to over 7 billion.  And by 2050, the US Census Bureau estimates there will be over 9.5 billion men women and children on the planet; all of them expecting food, water, shelter, and a first world standard of living.  The only way such demands can be met—if indeed they can be (and it’s a big “if”)—is through the increasingly sophisticated and strategic use of science and technology.

The level of scientific knowledge and technological ability that exists now underpins modern society.  Remove it, and things collapse.  But what is less obvious is that science and technology need to continually develop in a changing world.  As new challenges, needs and wants arise, we need a steady stream of new knowledge and new technology innovation.  Without science progress and technology innovation, our ability to sustain a healthy global society will not keep pace with the challenges to achieving this.

Of course, this is nothing new.  Science, technology and society have been intertwined for tens of thousands of years.  Homo sapiens are tool-makers and tool users—technology is in our blood.  Our history is one of progression through technology innovation—from early tools, to husbandry, to the industrial revolution and on to synthetic chemicals manufacture, nuclear power, semiconductor fabrication, and so on.

Some would say we’ve done pretty well out of this fascination with science and technology.  And by all accounts we have.  On a global scale, life expectancies are longer and quality of life is higher than ever before.

But this isn’t necessarily a sustainable trend.  With a growing population, dwindling resources and increasing demands on them, the pressures on science and technology to deliver the good are mounting.  At the same time, the world is changing in ways that could well stretch established approaches to ensuring adequate science and technology innovation to breaking point.

Take for instance the rate at which knowledge and ideas are now spreading, crossing boundaries, and influencing people. Or the increasingly strong links between human actions and environmental re-actions. And how about the ability of scientists to bend the material world to their every whim, even down to the scale of atoms and molecules?  In each of these cases, we are achieving more now than ever before in human history.  And the rate of progress is accelerating.  Separately, they challenge the effectiveness of conventional approaches to using science and technology in the service of society.  Together, they could well shake things up so much that established ways of doing things are no longer responsive to society’s needs.

These are the three “C’s:” Communication, Coupling and Control.  Communication: the flow and influence of information and ideas between people and institutions.  Coupling: the ever-closer relationship between society and the Earth.  And Control: our rapidly developing ability to control our surroundings from the atomic level through to the planetary scale.  Over the next few blogs in this series I will be talking about each “C” in more depth, and how together they potentially change the game when it comes to science and technology.

Next up: Coupling: Actions and consequences in a shrinking world

Notes

“Rethinking science and technology for the 21st century” is a series of blogs drawing on a recent lecture given at the James Martin School in Oxford.  This is a bit of an experiment—the serialization of a lecture, and a prelude to a more formal academic paper.  But hopefully it will be both interesting and useful.  I’ll be posting a “rethinking science and technology” blog every week or so, interspersed with the usual eclectic mix of stuff you’ve come to expect from 2020science.

Previously: Rethinking science and technology for the 21st century

Next: Coupling: Actions and consequences in a shrinking world

[3/19/09 correction - when the page was initially posted, it listed the third blog in this series - on communication - as being next]

Like it or not, society is dependent on science and technology.  The only way we can cram 6 billion people plus onto the earth and use resources at the rate we do, is through the support of scientific discovery and technology innovation.  Take our technology-based infrastructure away and civilization as we know it would collapse.

Perhaps more worrying, our dependency on science and technology is accelerating.  The world’s population continues to grow, lifestyle expectations are going up, and supporting technologies are becomes increasingly sophisticated.  But this “progress” can only be sustained through increasing the rate with which new discoveries are made and new technology innovations are implemented.

At some point this cycle of technology addiction probably needs to be broken if society is to avoid a rather nasty crash.  But I suspect that such a crash is some way off yet.  And it is entirely plausible that the solution for avoiding such a crash will itself arise from technology-based innovation.

Which means that if global society is to continue to mature and prosper, we have to get the whole science and technology enterprise right.

The only alternative is to face a radical “recalibration” of society, leading to a population level and demands on resources that are more in keeping with the Earth’s load-carrying capacity.

Assuming that we want to avoid a rapid and potentially catastrophic reduction in the world’s population, we need to ask whether the way we currently “do” science and technology is good enough.  And if it isn’t what needs to change?

Rethinking science and technology for the 21st century is going to be the subject of a series of blogs over the next few weeks—I’m afraid this is only the teaser!  I’ll be drawing on a recent lecture at the James Martin 21st Century School at Oxford University, which means that if you want a heads-up, you can always browse through the slides [PDF, 8.9 MB].  But I should warn you that the story might not be that clear from the slides alone.

This is a bit of an experiment—the serialization of a lecture, and a prelude to a more formal academic paper.  But hopefully it will be both interesting and useful.  I’ll be aiming to publish a “rethinking science and technology” blog every week or so, interspersed with the usual eclectic mix of stuff you’ve come to expect from 2020science.  First off will be the framing the problem, and introducing the “three C’s”—look out for it over the next week.

In the meantime, here’s the abstract from the original lecture, to whet your appetite:

As we move further into the 21st century, we are facing a confluence of three factors that will shake up the interface between society and science.  Nanoscale science and technology are enabling unprecedented control over matter, allowing living and non-living systems to be manipulated and used in radical new ways.  Innovative new approaches to communication and networking are facilitating the emergence of virtual partnerships that transcend geographical, organizational and social boundaries.  And society is now so closely coupled to the biosphere that our actions are stressing the system to a greater extent than ever before in human history.

This confluence of control, communication and coupling raises major challenges for society in the 21st century.   But it also contains the seeds of effective solutions.  However, to nurture and grow these seeds, new approaches to science and technology innovation will be needed.  These will include developing research agendas that are driven by social challenges, engaging citizens through building constituencies, and cultivating scientists with a clear sense of civic responsibility.

Update: The full series of posts on rethinking science and technology for the 21st century can be accessed here.

It’s been a big week for geoengineering.  First there was the news that the world’s largest geoengineering experiment to date is about to start in the Southern Ocean.  Following close behind was a new study on how geoengineering projects could potentially impact global climate change, ranging from covering vast tracts of desert with a reflective coating to suspending giant mirrors in space.  And today sees the publication of a new paper in the journal Nature indicating that, while fertilizing oceans with iron compounds can remove carbon dioxide from the atmosphere, the sequestration rate is far lower than previously estimated.

Reading through these and other accounts, it seems clear that the deliberate modification of the Earth’s environment on a vast scale is rapidly moving from the realms of fantasy to those of possibility.  Almost overnight it seems, geoengineering has become respectable.

Climate change is largely responsible—it has hammered home the message more than anything else perhaps that humanity is now able to influence the environment on a global scale.  Just the sheer magnitude of the possible impacts of global warming has made people think seriously about countering the effects through mega-engineering.  And the simple realization that our actions can make a difference to the global environment has contributed to an intellectual leap of imagination; scientists and engineers now have the audacity to think “yes we can” when it comes to countering anthropogenic climate change with engineered interventions.

This would all be wishful thinking though if it wasn’t for rapid advances in science and technology that are underpinning the emerging “yes we can” geoengineering mentality.  Although its early days still, scientists and engineers are beginning to develop the understanding and tools to put grand schemes into place, and start playing around with Earth’s systems on a global scale.

This confluence of need, awareness and ability is bringing new vigor to geoengineering.  And it’s hard to deny that its exciting stuff. … Imagine, at the very point where humanity begins to push the boundaries of sustainable existence under existing conditions, we develop the means to conform our global environment to our needs—inverse-evolution if you like.  We discover that science and technology give us a lever large enough to shift the world, metaphorically speaking.  We find that by controlling matter at the nanoscale, we can bend it to our will at the megascale.  In short, geoengineering appears to be humanity’s right-of-passage to planetary maturity.

But back up just a minute.  It seems there is something missing here.  Sure, we have the imagination and the ability to change things on a global scale.  But these abilities seem to far outstrip our understanding of their consequences.  It almost seems that scientists are in danger of applying the hypothesis-driven science of the laboratory to the whole world, while forgetting that when the hypothesis fails, there aren’t too many options to go back and start again.  And in the clamor to find technological fixes to technology-driven problems, it sometimes appears that we’ve forgotten to ask what we should do, as well as what we can do.

If we are going to get geoengineering right—and I think in the long-run it is as important as it is inevitable—we are going to need some serious ethical input to its development and application.  And while I generally avoid artificially slicing and dicing ethics, I think it would be no bad thing to further develop the idea of geoethics, as dealing with the appropriateness of decisions that affect societies on a global scale, and possibly over many lifetimes.

Of course, the concept of geoethics isn’t new—it’s been around in one form or another for decades, usually in the context of general anthropomorphic environmental impacts.  But to my mind the potential impact of geoengineering is such that it is going to need it’s own ethical framework that enables people to agree on a wise course of action.

Certainly, geoengineering raises many tricky issues.  For instance, we are still a long way from understanding and predicting the behavior and interactions of global systems, over short, medium and long timescales.  Interfering with systems we don’t understand is likely to lead to unanticipated consequences on a global scale.   And history has repeatedly demonstrated that simplistic interventions in environmental/ecological systems lead to adverse unintended consequences. On top of this, global interventions will have global impacts, meaning that great care needs to be taken in ensuring groups affected by potential outcomes are a part of the decision-making process.

These and other questions suggest to me that it’s worth developing the area of geoethics to apply specifically to geoengineering.  I’m not the first to propose this.  Perhaps the clearest articulation of geoethics in the context of geoengineering is Jamais Cascio’s article on Worldchanging.com from 2005.  Here’s what Cascio proposed as a definition back then:

“Geoethics is the set of guidelines pertaining to human behaviors that can affect larger planetary geophysical systems, including atmospheric, oceanic, geological, and plant/animal ecosystems. These guidelines are most relevant when the behaviors can result in long-term, widespread and/or hard-to-reverse changes in planetary systems, although even transient, local and superficial alterations can be considered through the prism of geoethics. Geoethical principles do not forbid long-term, widespread and/or hard-to-reverse changes, but require a consideration of repercussions and so-called “second-order effects” (that is, the usually-unintended consequences arising from the interaction of the changed system and other connected systems).”

He follows this with a set of core principles, which I’m not sure I entirely agree with (you can read them here).  Nevertheless, it’s a start.

Admittedly, there are international guidelines and agreements in place that already cover the responsible use of geoengineering to a certain extent.  Included in these is the Convention on Biological Diversity, which cautions against ocean fertilization (for instance)—a key geoengineering approach to sequestering carbon dioxide.  But what exists currently isn’t sufficient to engage people around the world in an integrated and informed debate over how to proceed appropriately.

The start of the Southern Ocean fertilization experiment was surrounded in controversy this week, but it went ahead anyway.  Even though it involves releasing six tons of iron over 300 square kilometers of ocean, it is a triflingly small experiment compared to what could be on the books in the near future.  If the global community are to get their heads around what is right and appropriate before the next big Earth-experiment comes along, now might be a good time to start working on geoethics for geoengineering—before it’s too late.

_________________________________

Note

For a good primer on various proposed geoengineering projects, and their possible impact on global warming, I would strongly recommend the just-published paper by Lenton and Vaughan; “The radiative forcing potential of different climate geoengineering options” (Atmos. Chem. Phys. Discuss., 9, 2559–2608, 2009).

Update, 1/29/09:  Alexis Madrigal’s article “Scientists Rank Global Cooling Hacks” on Wired Science provides an excellent distillation of the key information in the Lenton and Vaughan paper.  You also have to wonder – from the title of the piece – whether we need to start thinking about an emerging “geohacker” community!

Reports are coming in that Professor John Holdren – director of the Program on Science, Technology, and Public Policy at the Kennedy School, University of Harvard – is Barack Obama’s pick for science advisor, and head of the Office of Science and Technology Policy.

From ScienceDirect:

Strong indications are that President-elect Barack Obama has picked physicist John Holdren to be the president’s science adviser.

A top adviser to the Obama campaign and international expert on energy and climate, Holdren would bolster Obama’s team in those areas. Both are crowded portfolios. Obama has already created a new position to coordinate energy issues in the White House staffed by well-connected Carol Browner, former head of the Environmental Protection Agency, and nominated a Nobel-prize winning physicist, Steve Chu, to head the Department of Energy. That could complicate how the Office of Science and Technology Policy, which Holdren will run, will manage energy and environmental policy.

And from the Washington Post:

President-elect Obama will announce this weekend that he has selected physicist John Holdren, who has devoted much of his career to energy and environmental research, as his White House science adviser, according to a published report today.

The Obama transition office would not confirm Holdren’s selection. Last night, asked by The Post to comment on the science adviser search, Holdren responded by e-mail that he would be unable to comment because of his work with the Obama transition team.

Maintaining a longstanding tradition for presidential science advisors, Holdren is a physicist by training.  But his forte is the intersection between science, the environment and society – making him an exciting addition to the science and technology-based team Obama is rapidly assembling.

Update, Dec 20:

In his weekly address, President-Elect Obama has just confirmed the appointment of John Holdren as Assistant to the President for Science and Technology, Director of the White House Office of Science and Technology Policy, and Co-Chair of the President’s Council of Advisors on Science and Technology (PCAST).  He has also confirmed that Harold Varmus and Dr. Eric Lander will be the other co-chairs of PCAST.

From the address (viewable on YouTube here):

“Whether it’s the science to slow global warming; the technology to protect our troops and confront bioterror and weapons of mass destruction; the research to find life-saving cures; or the innovations to remake our industries and create twenty-first century jobs—today, more than ever before, science holds the key to our survival as a planet and our security and prosperity as a nation. It is time we once again put science at the top of our agenda and worked to restore America’s place as the world leader in science and technology.

Right now, in labs, classrooms and companies across America, our leading minds are hard at work chasing the next big idea, on the cusp of breakthroughs that could revolutionize our lives. But history tells us that they cannot do it alone. From landing on the moon, to sequencing the human genome, to inventing the Internet, America has been the first to cross that new frontier because we had leaders who paved the way: leaders like President Kennedy, who inspired us to push the boundaries of the known world and achieve the impossible; leaders who not only invested in our scientists, but who respected the integrity of the scientific process.

Because the truth is that promoting science isn’t just about providing resources—it’s about protecting free and open inquiry. It’s about ensuring that facts and evidence are never twisted or obscured by politics or ideology. It’s about listening to what our scientists have to say, even when it’s inconvenient—especially when it’s inconvenient. Because the highest purpose of science is the search for knowledge, truth and a greater understanding of the world around us. That will be my goal as President of the United States—and I could not have a better team to guide me in this work.”

Update Dec 21:  Holdren confirmed as next Assistant to the President for Science and Technology

Twelve months ago today I held a bag of multi-walled carbon nanotubes up before a hearing of the U.S. House Science Committee.  I wanted to emphasize the discrepancy between the current state of the science on carbon nanotubes, and a tendency to classify this substance as the relatively benign material graphite from a safety perspective.  So it is perhaps fitting that on the anniversary of that congressional hearing, the US Environmental Protection Agency is making it clear that carbon nanotubes are in fact, a new substance—and should be regulated as such.

Carbon nanotubes are often described as sheets of graphite—the stuff that makes pencil lead black—wrapped into a tube; leading to nanometre-thin “fibres” that are incredibly strong for their weight, and highly conducting—thermally as well as electrically.  But perhaps because of this simple imagery, they are often handled as if they are graphite—especially when it comes to using them safely.

Given the amount of time and money researchers and industry are pouring into producing and using carbon nanotubes, you would think that they are at least marginally different from their flat-sheeted cousins.  In fact the differences are anything but marginal: Wrapping the sheets associated with graphite into tubes radically changes the physical chemical and biological properties of these carbon-based materials—just like re-arranging the carbon atoms that make up soot into diamonds leads to the formation of a fundamentally different material.

Yet many companies continue to persist in claiming “it’s just graphite” when questions arise over the possible health impacts of being exposed to carbon nanotubes.

But all that is about to change.  Hot on the heels of clarification from the European Commission that carbon nanotubes (and other novel forms of carbon) need to be registered under the new REACH chemicals regulations, the US EPA has clarified their position on the material.  According to a just-released notice in the Federal Register, the EPA

“generally considers [carbon nanotubes] to be chemical substances distinct from graphite or other allotropes of carbon listed on the TSCA Inventory.”

In effect, this means that any company wanting to manufacture or import carbon nanotubes in the United States needs to submit a Pre Manufacturing Notice (PMN) to the EPA—unless the material can be shown to be on the Toxic Substances Control Act (TSCA) Chemical Substances Inventory. And the chances of that are pretty slim—at present.

EPA actually established their position on carbon nanotubes back in 2007, in a document clarifying how the agency saw TSCA applying to engineered nanomaterials [available here].  But the agency’s stance was so unclear that the Federal Register notice clarifying the situation was felt necessary.  In the words of the notice just published:

“current pre-notice inquiries to the Agency and questions in public forums still indicate a lack of clarity on this issue.”

This is a significant step forward for the US EPA, and a very welcome one.  Research is continuing to show that some forms of carbon nanotubes are potentially dangerous if inhaled in sufficient quantities.  Earlier this year, Craig Poland and colleagues showed that long thin multiwalled carbon nanotubes are potentially able to cause the disease mesothelioma if inhaled.  And more recently Anna Shvedova and co-researchers confirmed that inhaled single walled carbon nanotubes can have a unique impact on the lungs of mice.

Neither of these studies suggests that carbon nanotubes behave anything like graphite if they get into the lungs.  Yet companies persist with treating this material like graphite.

I’ve previously noted that carbon nanotube distribution companies like CheapTubes Inc. consider all forms of the material as being like graphite for health and safety purposes.  In fact, as of October 31, the Materials Safety Data Sheet posted on the CheapTubes website noted of carbon nanotubes:

“This material is listed on the US Toxic Substances Control Act (TSCA) Inventory”

There is little doubt now that this is, in fact, not the case.

The EPA’s clarification will certainly help ensure that this innovative material is used safely, and its full potential is realized without causing undue harm.  There are though, perhaps inevitably, still some unresolved issues.   These include various material use and production quantity exemptions that could be used by some companies to justify not applying TSCA to their nanotubes (see for instance the series of articles by Richard Denison on TSCA and nanomaterials).  But smart companies are realizing that compliance is the best way to ensuring safe and sustainable products—which is why a number of PMN’s for carbon nanotubes have already been submitted to EPA (again, Richard Denison’s blog at the Environmental Defense Fund has useful comments on this point).

There are however two rather large flies in the ointment:

The EPA clarification doesn’t add anything to the question of where many other engineered nanomaterials stand on the regulations front.  Carbon nanotubes are chemically distinct from other forms of carbon, and so are easily defined under TSCA as news substances.  But if you take something like titanium dioxide or silver and form it into nanoparticles, current regulations make no distinction between the nano and non-nano forms of the material—even though research suggests the nano-form may be more harmful.

Just as importantly, submitting a PMN for a specific type of carbon nanotube material opens the way for that material being added to the TSCA Chemical Substances Inventory.  And once there, other companies are free to make, use and sell the material.  As Richard Denison writes,

“Once reviewed and placed on the TSCA Inventory, any company can manufacture and use the nanomaterial without even having to notify EPA it is doing so.” (unless EPA simultaneously issue a Significant New Use Rule)

Yet researchers are only just beginning to discover what might make different carbon nanotubes harmful, and how to avoid that harm.  What are the chances therefore of carbon nanotubes being added to the TSCA inventory before we have a good handle on how to use them safely?

The bottom line here is that resolving the regulatory status of carbon nanotubes is an important step forward.  But there is still some way to go before this material is regulated in a way that will encourage innovation while preventing undue harm—whether to people or the environment.

And while carbon nanotubes can perhaps leave the couch feeling a little more confident about themselves, we shouldn’t forget that there are still plenty of other materials out there that are suffering from a nano-induced identity crisis.

Painted metal roofs are cheap, convenient, and usually very durable.  But over the past two years, a rash of accelerated ageing has blighted pre-painted steel roofing in Australia.  And intriguingly the ageing—which affects the coating—seems to be localized to small patches, taking on the form of fingerprints, handprints and even footprints.

The culprit it seems is sunscreen that is spilt or otherwise transferred to the roofing by construction workers during installation. And not any old sunscreen—this would appear to be a uniquely nano phenomenon.  But I get ahead of myself…

Pick up a bottle of sunscreen and there is a fair chance these days that it contains nanoparticles, engineered to absorb and reflect away harmful UV radiation.  Many manufacturers are introducing lines of nanoparticle-containing sunscreens as alternatives to those using more conventional organic chemicals, and it’s not hard to see why: the active ingredients in these nano sun blocks are generally more gentle on the skin than their non-nano counterparts; they are made to sit on the surface of the skin rather than penetrate into it; and if designed well, they continue to block UV radiation for several hours after application.  And of course, they go on clear, giving a product that works well and looks good.

But each year as the sun and the sunscreen come out, questions over the safety of nano-formulations are raised.  Can these nanoscale particles penetrate through the outer layers of the skin to the underlying living cells, and even the bloodstream? And if they get there, what harm could they cause?  So far, most studies suggest that nanoparticles in sunscreens stay where they are supposed to—on the skin, not in it.  Yet there is another question that has been bobbing along just under the surface for the past few years: could mixing nanoparticles, sun and moisture lead to a chemically corrosive mix that is bad for the skin?

The issue in question is photocatalytic activity.  Titanium dioxide, and to a lesser extent zinc oxide, are photoactive—they have the ability to absorb UV, and in the presence of moisture convert benign water molecules into chemically active hydroxyl free radicals.  These highly reactive chemicals could spell bad news for sunscreen users if they are generated in large amounts—eating away the components that hold the sunscreen together, and even possibly causing skin damage if they get below the surface and into cells.

Fortunately, manufacturers and users of titanium dioxide have long been aware of this propensity to generate free radicals, and have found ways of suppressing it in sunscreens. Photocatalytic activity depends on the crystalline structure of titanium dioxide.  Anatase and rutile forms of titanium dioxide have the same chemical formula but different crystalline structures. And, as it turns out, different properties. Make nanoparticles from anatase titanium dioxide, or a mix of anatase and rutile, and you have a powerful source of harmful hydroxyl radicals in the presence of water and UV. But make nanoparticles out of rutile titanium dioxide alone, and photocatalytic activity is reduced substantially.

However, even rutile titanium dioxide particles show some photocatalytic activity.  Early uses of rutile titanium dioxide as a white pigment in outdoor paint were plagued by the paint turning chalky after too much sun exposure. The problem was tracked down to hydroxyl radicals being produced and degrading the paint’s binder.  The solution: coat the particles with a material that prevents free radical formation—no more chalky paint, and coatings that will last for years in the fiercest sun.

Makers of titanium dioxide-based sunscreens use a similar trick to retain the functionality of nanoparticles while avoiding the potentially harmful photocatalytic properties. For instance Optisol—a UV blocking agent made by the company Oxonica—incorporates a minute amount of manganese into the crystal lattice of rutile titanium dioxide nanoparticles.  This doping allows the absorbed UV energy to be dissipated while virtually eliminating the formation of free radicals.  Not only does this make sunscreens using Optisol potentially safer; they also last longer in the sun, as there are fewer free radicals to break down other ingredients in the product.

So all looks rosy for nano-enabled sunscreens.  At least, it did until the publication of a recent paper.  And this is where we get back to pre-painted steel roofs. Since mid 2006, researchers in New South Wales Australia have noticed unusual defects developing in newly installed pre-painted steel roofs.  The damage is typically localized to areas of pressure contact, often taking the form of fingerprints or shoe impressions.  And it results in accelerated weathering—in one example, patches of a roof appeared to age an equivalent of 15 years in only 18 months. The culprit?  Nanoparticle-containing sunscreens, which are accidentally transferred to the roof during installation by touching or splashing.

In the paper “The interaction of modern sunscreen formulations with surface coatings,” [Progress in Organic Coatings62: 313:320. 2008] authors Phil Barker and Amos Branch systematically track down the underlying cause behind the unsightly blemishes.  Out of ten sunscreens tested—four containing no nanoparticles, five containing titanium dioxide nanoparticles, and one containing zinc oxide nanoparticles—all but one of the nanoparticle-based sunscreens consistently degraded samples of pre-painted roofing surface exposed to sunlight for 12 weeks.  In contrast, the non-nano products had no obvious deleterious effect.  In the worst case, the roofing lost over 85% of its gloss (a measure of degradation) in just six weeks.

Digging a little deeper, Barker and Branch pinned the effect to nanoparticles in all but one sunscreen acting as photocatalysts, and generating hydroxyl radicals in the presence of UV radiation and water.  Despite assumptions that nanoparticles in sunscreens are engineered not to produce significant amounts of free radicals, these products were generating them fast enough to significantly damage roof coatings in a matter of weeks!

So have we had the wool pulled over our eyes?  Are these supposedly benign nano-sunscreens we are slathering on our skin adding to our wrinkle-count before our time, and perhaps more besides?

Before jumping to conclusions, it is worth taking stock of what is known, and what is not.  While the study showed all but one of the nanoparticle-based sunscreens had some adverse effects on the roofing, these effects varied greatly between products.  The sunscreen using nano-zinc oxide particles led to a 55% reduction in gloss over 12 weeks, while in the worst case, a sunscreen containing 4% titanium dioxide led to a 95% reduction in gloss over 12 weeks.  Assuming that the reduction in gloss is associated with the formation of hydroxyl radicals (and the evidence presented by Barker and Branch arising from a logical sequence of laboratory experiments is pretty convincing), there is still uncertainty over how harmful these would be when generated on the skin of a sunscreen-user.  To cause damage, the hydroxyl radicals would need to penetrate deep into the skin and into cells before loosing their potency, and if the nanoparticles stay on top of the skin where they are supposed to, significant penetration may not occur.

Then there is the anomalous nano-sunscreen that didn’t show an appreciable effect.  A nifty piece of X-ray diffraction analysis in the Barker and Branch paper showed that the titanium dioxide nanoparticles in the roof-damaging sunscreens were an anatase/rutile mix, while the nanoparticles in the benign sunscreen were comprised of rutile titanium dioxide alone.  Clearly crystalline form matters, as Oxonica realized when they selected the less-active rutile form of titanium dioxide as the basis for Optisol.

This study demonstrates that it is possible to create nanoparticle-based sunscreens that do not generate significant amounts of hydroxyl free radicals.  But the bottom line here is that some nano-based sunscreens are being sold (in Australia at least) that contain photoactive nanoparticles which generate hydroxyl radicals in the presence of water and sunlight.  This raises questions about the impact of these products on users over time and, perhaps more significantly, their impact on the environment.  A photocatalytic titanium dioxide particle released into the environment will continue to generate hydroxyl radicals as long as it is exposed to UV radiation—because this is a catalytic process, the particle is not destroyed in the process, but just carries on doing its stuff; day after day, year after year.

But perhaps the biggest question here is one of regulation.  In the US, the Food and Drug Administration does not currently discriminate between anatase and rutile titanium dioxide particles in sunscreens, or doped and un-doped particles [Sunscreen Drug Products For Over-The-Counter Human Use: Final Monograph.  May 21 1999.  PDF, 144 KB].   This may change following further consultation on the use of nanoscale titanium dioxide and zinc oxide in sunscreens [see Sunscreen Drug Products For Over-The-Counter Human Use; Proposed Amendment of Final Monograph; Proposed Rule.  August 27 2007.  PDF, 424 KB].  But in the meantime, what is to stop manufacturers using potentially harmful forms of titanium dioxide in sunscreens?  And how will consumers be able to distinguish between companies that have got it right, and those that have not?

It seems that if we are not careful, nano-sunscreens could be making their mark on more than just pre-painted steel roofing.

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This post first appeared on the SAFENANO blog in June 2008

Why nano?  Why care?  For non-nanotech initiates, an obsession with nanotechnology must sometimes seem a bizarre occupation of the sad and lonely.  And even within the nanotechnology community, who hasn’t had occasional doubts over the legitimacy of singling out “nano” as something special?  Yet occasionally a piece of work comes along that helps put things back into perspective.  For me, a paper just published on-line in the journal Nano Letters did exactly that.

To be quite frank, the paper’s title is not what I would call inspirational.  But dig below the surface, and you unearth an object lesson in what makes nano so intriguing, and why taking a fresh look at possible health and environmental impacts is so important.  First the science though.

The Science

The paper in question is “Controlled Manipulation of Giant Hybrid Inorganic Nanowire Assemblies” by Fung Suong Ou, Manikoth M. Shaijumon, and Pulickel M. Ajayan, published on-line in Nano Letters, May 29 2008.  Unfortunately, a subscription to the journal is needed to view the paper, but the supplemental information is freely available (here), and well worth looking at.  

In brief, the authors used a nanoscale fabrication technique to construct long, straight, carbon nanotubes capped with gold nanowires.  Think “magician’s wand” with the nanotube as the stem and the gold as the white tip, and you will get the idea.  The nano-wands (for want of a better description) were between 100 nm and 150 nm wide, and over 100 mircometres (100,000 nm) long.  Micrographs in the paper show rafts of uniform-length nano-wands stacked side by side, with individual wands fraying off at the edges.

But this is where things get interesting.  These long, straight artificial rods were designed to have one end that was hydrophobic (water-repelling; the carbon end), and one end that was hydrophilic (water-seeking; the gold).  When dispersed in water, these wands formed a uniform suspension.  But when an organic solvent—dichloromethane (DCM)—was added to the mix, the nano-wands assembled into shells around the DCM, with the black carbon nanotubes facing in and the gold tips facing out.  With a bit of shaking and ultrasonic agitation, one large gold-coloured sphere was formed, separating the DCM from the water.  Reversing the process by suspending the nano-wands in DCM and adding water, a large black sphere assembled; separating the water from the organic solvent.  Black, because in this case the carbon nanotube “tails” were pointing outward.

Using the same fabrication technique, the researchers demonstrated a couple of other tricks.  By adding a band of the metal nickel below the gold tip, the nano-wands could be made magnetic—so now the spheres separating the two liquids could be moved around using a magnetic field.  And by adding an ultraviolet light-degradable hydrophobic chemical to the gold end of nano-wands, spheres were constructed that quite literally turned inside-out under UV irradiation.

The Promise

Nanotechnology is all about functionality—making materials and products that behave in new and unusual waysbecause they have been engineered at an incredibly fine scale.  This new and unusual behaviour might in some cases be due to the unusual physics and chemistry of small clusters of atoms (such as the size-related fluorescence of quantum dots).  But it can just as easily arise from engineering a material at such a fine scale that it can be used in new ways (such as making antimicrobial silver particles small enough to be incorporated into a miscellany of products); or constructing materials at the nanoscale with such sophistication that new properties emerge (multi-functional nano-therapeutics for instance).  The nano-wands are most definitely in the latter categories—their functionality arises from their smallness and sophistication.  

The important point here is that, while size matters, performance matters more.  And so while these nano-wands are technically larger than the 100 nm limit usually (and somewhat arbitrarily) imposed on nanotechnology, they nevertheless represent an ability to create a novel functional material through sophisticated engineering at a very fine scale.

And what functionality!  This is a crude material compared to what could be achieved using similar construction techniques, but even so the nano-wands behave in a most unusual way.  Functionally, they are reminiscent of polar molecules, and the spheres they form are analogous to micelles—“capsules” formed by organic molecules with opposing hydrophobic and hydrophilic ends.  But by engineering them at the nanoscale out of inorganic materials, structural and functional possibilities open up that are way beyond the realm of chemistry alone.  

It is easy to imagine how this material could be used to encapsulate and collect chemical spills in the environment.  Or deliver drugs to where they are needed in a very targeted way (only releasing their payload by disassembling when the right signal is received).  Yet the work of Fung Suong Ou and colleagues hints at much greater things.  Using the same basic technology, there is nothing to prevent the construction of multi-component nanomaterials that can assemble and re-assemble in many different ways, depending on their environment and the stimuli they receive.  As the paper’s authors’ conclude, 

“This controlled engineering feat at the nanoscale that allows well-controlled assembly and manipulation could lead to the creation of smart materials that are a cornerstone for the development of nanotechnology-based applications.”

The challenge

But stimulating as the science is, this paper is also an object lesson in why new thinking is needed on possible risks to human health and the environment, if such technologies are to succeed.

First and foremost, the paper comes hot on the heels of Poland et al.’s study linking some forms of multi-walled carbon nanotubes to precursors of mesothelioma—a disease more usually associated with asbestos exposure.  Poland’s research suggests that carbon nanotubes which are thin, longer than 15 – 20 micrometres, straight, and dispersible, could lead to the disease if inhaled.  The nano-wands in the Ou et al. paper are around 150 nm in diameter, something over 100 micrometres long, straight, and apparently dispersible—in other words, exactly the types of fibres which Poland’s work suggests more research is needed on before the possible health implications are understood.

It’s too early to tell whether Ou’s nano-wands will have their own unique risk-profile.  But their inevitable comparison with the nanotubes used in Poland’s study and the possibilities of dispersive use hinted at in the accompanying press release do raise important questions about their safety.  The important point here is not that this particular material might show harmful behaviour, but that there is always the chance that novel behaviour can lead to unanticipated harm—unless the right questions are asked early on.  And this most definitely requires new thinking on what those questions are, and how they might best be answered.

The second object lesson in new challenges concerns regulations.  Unless used as a drug or pesticide, substances are typically regulated according to their chemical makeup.  It’s an approach that was developed at a time when the terms “chemical” and “substance” were interchangeable.  But Ou’s nano-wands challenge this paradigm.  

These nano-wands and other hybrid substances have no unique chemical identity, and so potentially slip through the net of many existing regulations.  Yet they display a functionality that depends on their physical form and complex makeup, which is not predictable from their chemical components.  And regulations are needed that recognize this.  If effective approaches are to be developed to ensure the safe use of this emerging class of material, new thinking is needed on how substances are classified and regulated.

The bottom line

Why nano? As Ou’s work shows, we can potentially do things with nano that are way beyond any other technology at our disposal.  And when nano is combined with other technologies like biotech and information tech, the possibilities become endless.

Why care?  Because nano will change your life, whether you like it or not.  And you might want to make sure that it is a change for the better, not for the worse.

And the nano-wands?  These have tremendous potential as an innovative new material.  Lets hope that their development is matched by equally innovative thinking on using them safely.

Further resources

Paper: Controlled Manipulation of Giant Hybrid Inorganic Nanowire Assemblies

Supplemental Material to the paper

Managing the Effects of Nanotechnology.  J. Clarence Davies

Paper: Carbon nanotubes introduced into the abdominal cavity of mice show asbestos-like pathogenicity in a pilot study

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This post first appeared on the SAFENANO blog in May 2008