The immediate lessons from the Deepwater Horizon disaster are pretty obvious – we (or at least somebody) messed up!  But what about the less-obvious lessons – especially those concerning technology innovation and how it’s handled?  The Fall 2010 issue of Findings – the University of Michigan School of Public Health Alumni magazine – contains a short piece addressing just this question.  As is increasingly becoming my habit, here’s an earlier draft of that article.  As well as providing a little more information that the published piece does, it allows an interesting comparison between a good draft (what I think works) and an expertly edited final article (what the editor thinks will work).  As usual, I was more than impressed by how a good editor can sharpen a piece up.

In today’s increasingly crowded, interconnected and resource-constrained world, we are more dependent on technology innovation than at any previous time in human history.  By 2050, over nine billion people will be placing unprecedented demands on the earth’s resources – a demand that will only be met through developing and using new technologies.

Yet technology innovation comes with its own challenges.  The Deepwater Horizon oil spill in the Gulf of Mexico provides a sobering reminder of what can go wrong when we trust in technology without investing sufficiently in the future.  Devastating as this disaster has been though, it is only one small example of the challenges we will face as a global society as resources become scarcer, demands become greater, and our technological reach threatens to exceed our ability to handle it safely.

If a sustainable future is to be built on the effective development and use of technology innovation, we need to rethink how we reap the benefits of technology.  The full impact of the Deepwater Horizon spill will take years to evaluate.  But underlying the immediate impacts of the disaster is a story of how technology innovation failed, and the lessons that can be learned from this failure; not just so human and environmental disasters of this magnitude can be avoided in the future, but also so that we begin understand more fully how to develop and use new technologies more responsibly.

The technology being used on the Deepwater Horizon rig was at the cutting edge of innovation.  Drilling at depths of 5000 feet below the surface of the sea – far beyond the reach of direct human intervention – the operation was pushing the bounds of the possible.  Until the disaster, this was a story of technology innovation allowing us to tap previously inaccessible oil reserves.  But there is a less obvious story here – one of emerging technologies that could have been used to mitigate the impacts of the spill, if only there had been sufficient forethought and investment to develop them to the point of usability before they were needed.

As it is, the use of advanced technologies associated with the Deepwater Horizon rig failed on three counts:  The potential consequences of using an unproven technology were not explored sufficiently; there was inadequate investment in understanding, avoiding and mitigating risks upstream; and there was a lack of foresight in developing new technologies to manage the consequences of failure.  Greater foresight, investment and upstream action on each of these three counts could have helped avoid or reduce the impact of the ensuing disaster.

Given the uncertainty surrounding the drilling technology being used and the potentially severe consequences of errors, more realistic scenario planning would have helped prepare for low probability but high impact risks.  Coupled to this, more strategic research into the potential risks associated with deepwater drilling, together with greater stakeholder engagement, could have helped industry, regulators and others more effectively manage the consequences of the disaster.  And more proactive up-front investment in remediation technologies could have provided more effective tools for managing the consequences of the disaster.

This last issue sticks out like a sore thumb.  In the face of increasing global challenges, it is all too easy to latch onto the naïve assumption that technology-based solutions will present themselves as and when needed:  The belief that technology innovation will save the day is a pervasive one.  Yet as oil began gushing into the Gulf of Mexico, potential new technology-based solutions to managing the spill were conspicuous by their absence – not because the science wasn’t there, but because there had been insufficient investment in developing it into commercially viable technologies.  Technology platforms such as nanotechnology and synthetic biology for instance have the potential to support oil cleanup solutions that are significantly more effective and environmentally benign than existing ones.  But in the absence of concerted efforts to translate cutting edge science into viable commercial products, BP ended up using an established dispersant with questionable environmental and human health impacts, and uncertain consequences when introduced to an oil plume 5000 feet below the sea’s surface.

If we are to benefit from emerging technologies – to ensure that they help address pressing challenges, and do not create more problems than they solve – we clearly need to think differently about how they are developed and used.  There needs to be far greater awareness of the consequences of getting complex and far-reaching technologies wrong, a new willingness for stakeholders to work together to find sustainable solutions, and new thinking on how potential risks can be identified and addressed as early as possible in the development cycle.  Because as emerging technologies become increasingly complex and powerful, the consequences of mis-steps on public health and the environment will only become more catastrophic.

This will require better understanding of how emerging technologies can lead to unexpected impacts on human health.  And it will depend on developing a deeper appreciation of how technology innovation can be nudged along more responsible – and ultimately more sustainable and beneficial – pathways.  In effect, we need a new paradigm that places a science-based understanding of risk at the center of sustainable development.

The Risk Science Center at the University of Michigan is at the forefront of this movement toward a new risk paradigm.  By integrating cutting edge science, multi-stakeholder partnerships and effective communication, the Center is working towards avoiding harm from emerging technologies while ensuring their benefits are fully realized.  It’s an approach that will significantly reduce the chances of future adverse health impacts – but it’s also one that makes sound business sense.

Devastating as the Deepwater Horizon disaster has been, it is a timely wakeup call to the consequences getting technology innovation wrong – one that has relevance far beyond the confines of BP.  As we enter an age where we are more dependent than ever on getting technology innovation right, corporations, policy makers, policy influencers and citizens all need to be a part of a process that supports the emergence of responsible technologies.  But for this process to lead to a sustainable future, it must be built on the best possible information if it is to succeed – which means investing proactively and strategically in the science of identifying, understanding and avoiding potential risks.  The alternative is to take increasingly risky gambles with our technology-supported future.  And as any seasoned gambler knows, the house always wins – eventually.

The version of this piece published in Findings can be accessed here.

Friends of the Earth (FoE) do not like nanoparticle-based sunscreens.  This has been evident for some years – back in 2006 the organization published the report Nanomaterials, Sunscreens and Cosmetics: Small Ingredients, Big Risks, and every year since then they have had something to say on the subject.

This year’s web-based piece leaves now doubt about FoE’s stance on nanotechnology-enabled sunscreens.  The recently posted article starts:

While you’re planning your summer vacation and thinking about what to pack, don’t forget the sunscreen — but make sure it doesn’t have manufactured nanoparticles in it!

But what is the reasoning behind this stance?  Helpfully, FoE have also posted six cases of what they describe as evidence “of risks from manufactured nanomaterials in sunscreen.”

As these are evidence-based statements, I thought it would be worth while going through them, and taking a look at the evidence they are based on:

FoE: “Manufactured nanomaterials used in sunscreens (such as zinc oxide and titanium oxide) can Damage human colon cells: A study from the University of Utah showed that nano zinc oxide is toxic to colon cells even in small amounts. The scientists called for more research and warned that the evidence is especially concerning for children who are more likely to accidently ingest sunscreen. The colon is vital because it eliminates food waste and absorbs important nutrients.”

This was a study that looked at interactions between zinc oxide (ZnO) particles and cells derived from the human colon, and was carried out in vitro (i.e. in a cell culture rather than in animals or people).  It did indeed indicate that nanometer scale ZnO particles were around twice as potent as larger ZnO particles in their ability to kill these cells under idealized conditions.  But the research also emphasized that direct contact with the cells was needed for a nanoscale particle-related effect.  In fact, the title of the paper was “ZnO Particulate Matter Requires Cell Contact for Toxicity in Human Colon Cancer Cells,” emphasizing this point above the higher potency of the more finely structured particles.

The research was interesting, but did not resolve whether zinc oxide particles could survive long enough in the gut to come into contact with cells lining the colon, whether interactions like those observed in the laboratory are plausible under real-world conditions, and what levels of exposure would be needed to cause significant harm.  The research also indicated that larger particles of zinc oxide – similar to particles that have been used in sunscreens and other topical creams for decades – were toxic to cells under the conditions of the study.

FoE: “Manufactured nanomaterials used in sunscreens (such as zinc oxide and titanium oxide) can Damage brain stem cells in mice: A study from China found that zinc oxide nanoparticles can damage the brains of mice by killing important brain stem cells. In another study, Japanese scientists injected pregnant mice with nano titanium dioxide and recorded changes in gene expression in the brains of their fetuses. These changes have been associated with autistic disorders, epilepsy and Alzheimer’s disease. Though more studies are necessary to know if this damage to would occur in humans, these studies with mice serve as important warnings. Such studies have encouraged scientists in the United Kingdom to explore the link between manufactured nanomaterials and Alzheimer’s disease. At the end of last summer, scientists at the University of Ulster were funded by the European Union to conduct more research.”

The China study was once again carried out using cell culture rather than in animals, and as a consequence the results are very hard to interpret.  What the researchers did find is that, under rather idealized conditions, it is possible to cause neural stem cells from mice to undergo apoptosis (controlled cell death) if they are exposed to enough zinc-containing material.  Importantly, the study did not indicate that cell death was associated with particle size – large particles, small particles and even dissolved Zinc all gave similar results.

The Japanese study on the other hand injected mice with extremely high concentrations of titanium dioxide (TiO2) particles – way, way higher than levels likely to get into people’s bloodstream.  Researchers saw qualitative changes in gene expression in fetuses and mice pups that are indicative of a number of disorders.  But – and this is important – there is no direct link between gene expression as measured in this study, and the onset of the neurological diseases mentioned above.  All this study indicates is that injecting TiO2 nanoparticles directly into the blood at extremely high levels causes brain cells in fetuses and pups to respond in some way.  Without knowing how those responses translate into disease (if they do at all), and what the relationship between dose and response is, this study does not provide information on the likelihood of TiO2 nanoparticles impacting the brain.

FoE: “Manufactured nanomaterials used in sunscreens (such as zinc oxide and titanium oxide) can Penetrate healthy adult skin: Isotope-labeled zinc used in nanosunscreens can potentially reach the blood stream and urine of humans, suggests an Australian study by Macquarie University’s Professor Brian Gulson. This study undermines claims that nanosunscreens will stay on the outer layers of dead skin.”

This study by Brian Gulson and colleagues has yet to be published, and so it is a little premature to draw conclusions from the findings.  However, from what has been discussed in the public sphere, the study does not show conclusively that manufactured nanoparticles used in sunscreens can penetrate healthy adult skin.  The study cleverly used sunscreens containing nanoparticles incorporating a stable isotope of zinc – one that is found naturally at very low concentrations.  This meant that, by applying the specially formulated sunscreens to volunteers and monitoring their blood and urine, researchers could tell conclusively whether the zinc from the sunscreen was getting into the body.  What they could not tell was whether it was particles or dissolved zinc getting through the skin.  And as zinc oxide is soluble, there’s a high chance that the very low levels of sunscreen-related zinc that were found in body fluid samples were associated with the stuff dissolving, rather than the penetration of nanoparticles.

We’ll have to wait for the paper to be published before any firm conclusions can be drawn from this work.  But if dissolution is the dominant mechanism here, it suggests that sunscreens relying on larger ZnO particles (and, coincidentally, recommended by Friends of the Earth), may lead to just as much zinc getting into the body as those using nanoscale ZnO particles.

It should also be noted that the results of this study are specific to ZnO – they cannot be extrapolated to other materials, such as TiO2.

FoE: “Manufactured nanomaterials used in sunscreens (such as zinc oxide and titanium oxide) can Travel up the food chain from smaller to larger organisms: A study by researchers at Arizona State University, the Georgia Institute of Technology, and Tsinghua University in China found through a dietary experiment that Daphnia (a “water flea” that provides important nutrition for aquatic life) can transfer nano titanium dioxide to larger organisms (in this case Zebrafish). This study is of great concern because it shows that manufactured nanomaterials with toxic properties could end up in the animal food chain at large.”

This is very true for the material that was the subject of the cited study – nanoscale TiO2 – although the results do not necessarily hold for other nanoscale materials.  At the same time, the study showed that the higher organisms in this case – zebrafish – accumulated more nanoscale TiO2 directly than they did through eating the lower organism – daphnia.

Where nanoscale materials used in sunscreens go in the environment, where they accumulate, and the impact they have, are all important questions.  But without information on toxicity and amounts of material potentially transferred, it is hard to say whether the transfer of these materials up the food chain is significant or not.

FoE: “Manufactured nanomaterials used in sunscreens (such as zinc oxide and titanium oxide) can Damage important microbes in the environment: Scientists at the University of Toledo found that nano titanium dioxide inhibited the function of bacteria after just an hour of exposure. Manufactured nanomaterials from sunscreens can easily wash off of the body in the shower and end up in wastewater and the wider environment, which could affect microbes that are helpful to ecosystems and sewage treatment plants.”

The link here is to a report from a presentation at an American Chemical Society meeting in 2009.  The full peer reviewed paper can be found here.  The published research indicates that nanoscale TiO2 can compromise the integrity of some (not all) bacterial cell membranes at certain concentrations under certain (laboratory) conditions.  The consequences of this are unknown, and it certainly isn’t possible to extrapolate from the research what the environmental impacts of nanoscale TiO2 releases might be, or at what concentrations in the environment an impact is likely.  More importantly, the published work showed no impact of nanoscale ZnO on bacteria at the concentrations used. In other words, the research does not show that nanoscale zinc oxide can damage important microbes in the environment.

FoE: “Manufactured nanomaterials used in sunscreens (such as zinc oxide and titanium oxide) can Travel from mothers to unborn fetuses: Nanoparticles up to 240 nm in size can cross into human placentas, meaning that the toxicity of manufactured nanomaterials could extend across generations.”

This is an important study, as it shows that particles of a specific type injected into the bloodstream can potentially cross over the placental barrier and into the fetus.  The research was carried out using human placenta, but outside the body and under laboratory conditions.  The particles used were polystyrene particles.  And the research was aimed at working out how to get beneficial drugs to the fetus.  The authors of the work note that high exposures were used, and that transport fro the placenta may well be influenced by particle composition and surface coating.  They go so far as to say that the research cannot be generalized across different types of nanoparticles.  In fact, while polystyrene particles up to 240 nm were observed to cross over the placental barrier in this study, the authors point out that in another study using the same system, polyethylene glycol coated gold particles up to 30 nm in diameter were not able to cross the placenta.

Each of the studies cited above is scientifically interesting.  But none of them seem to provide clear evidence that TiO2 or ZnO nanoparticles in sunscreens present a plausible risk to human health.  In many cases, they are associated with very artificial test systems that shed light on the science of how nanoparticles behave under certain conditions, but are far removed from real world situations.  Specifically, the studies do not shed light on whether nanoparticles in sunscreens can get into the body (the weight of scientific evidence is that they cannot get through the skin), whether the body’s defense mechanisms deal effectively with any nanoparticles that do get through (the evidence is that they can), and how much stuff is needed in the body to cause disease (a number of these studies indicate rather large quantities of material are needed).

In other words, the science is far from compelling in indicating that nanoparticles in sunscreens are a bad thing.  In fact, the current state of the science suggests that nanoparticles in sunscreens stay on top of the skin rather than penetrating it, are an effective and long lasting barrier against Ultraviolet radiation from the sun if applied correctly, and avoid some of the health concerns associated with non-nano sunscreens.  This is probably why another environment group – the Environmental Working Group (EWG) – recently recommended a range of nanoparticle-based sunscreens.   In fact, in a recent review EWG stated

Our top-rated sunscreens all contain the minerals zinc or titanium. They are the right choice for people who are looking for the best UVA protection without any sunscreen chemical considered to be a potential hormone disruptor. None of the products contain oxybenzone or vitamin A and none are sprayed or powdered.

Part of the problem here is that there is a lot of speculation going on about the pros and cons of nanoscale TiO2 and ZnO in sunscreens, and not a lot of analytical thinking.  What would be really helpful is some numbers on how risky these products might be.  Of course, we don’t have the data to state conclusively what levels of nanoparticles in sunscreens are safe – and there is a compelling case for more research here.  But we should at least be able to guestimate the numbers for a worst case scenario, based on the current state of the science.

So here’s a question back to Friends of the Earth – based on the current state of the science, what number would you put on the risk to human health of using nanoparticle-based sunscreens under a plausible worst-case scenario?

I’ll reiterate this question in a follow-up blog.  But it strikes me that, if we can begin to get some numbers on the table – even if they are just rough estimates, we might be able to cut through some of the speculation here and open up a reasonable discussion on the safety or otherwise of nanotechnology-enabled sunscreens.

]]> http://2020science.org/2010/06/08/friends-of-the-earth-come-down-hard-on-nanotechnology-are-they-right/feed/ 11 http://2020science.org/2010/05/28/nano-dispersants-and-nano-hysteria-time-to-think-about-the-science-folks/ http://2020science.org/2010/05/28/nano-dispersants-and-nano-hysteria-time-to-think-about-the-science-folks/#comments Sat, 29 May 2010 00:19:00 +0000 Andrew Maynard http://2020science.org/?p=3250

Catching up with my email after a long day off the net, I see that a group of Non Government Organizations (NGOs) are urging EPA not to allow the use of an alleged nanotechnology-based dispersant in the Gulf of Mexico.  The letter from thirteen organizations was covered in a piece by Andrew Schneider on AOL Online earlier today – which had considerable pickup on the web from what I can tell.

Sadly, a combination of limited information from the company – Green Earth Technologies – and poor understanding by others – seems to have led to the situation being dominated by misunderstanding and misinformation.

Green Earth Technologies has been lobbying hard to get their product G-MARINE™ Fuel Spill Clean-UP! used in the Gulf of Mexico for some days now.  According to the company

G-MARINE Fuel Spill Clean-UP! is a unique blend of plant derived, water based and ultimate biodegradable ingredients specifically formulated to quickly emulsify and encapsulate fuel and oil spills. These plant derived ingredients are processed to form a colloidal micelle whose small particle size (1-4 nanometers) enables it to penetrate and breakdown long chain hydrocarbons bonds in oils and grease and holds them in a colloidal suspension when mixed with water. Once oil has been suspended in a nano-colloidal suspension, there is no reverse emulsion; the oil becomes water soluble allowing it to be consumed by resident bacteria in the water. This dispersant formula is protected by trade secrets pursuant to Occupational Safety and Health Agency (OSHA) Standard CFR-1910 1200. The ingredient list has been reviewed by the US EPA and contains no ingredients considered hazardous by OSHA.

Is seems to have been the “nano” in the above description – leading to the substance being dubbed a “nano-dispersant” – that has raised eyebrows.

The nano here is very small micelles – “particles” of molecules formed from molecules with one end that is attracted to water, and one which repels water.  I place particles in inverted commas as these really very small bubbles of one liquid in another – hardly like particles at all.  And like bubbles, they probably don’t last that long.

Reading the company’s Materials Safety Data Sheet (MSDS), it’s possible to get a good idea what is in the micelles – mainly natural oils, mild detergents and surfactants.  But the MSDS doesn’t go as far as being specific about the physical nature of the micelles.  This is not too surprising perhaps as micelles are commonly used in products, as well as occurring naturally.  They are also transient – they fall apart reasonably fast, just like bubbles.

Now to the letter from the NGOs.  It starts out

It has come to our attention that Green Earth Technologies (GET), Inc. is seeking approval from the EPA to disperse a large quantity of manufactured nanoparticles in the Gulf of Mexico, stating that the dispersal would remedy the oil spill recently suffered by the region. The for-profit company claiming to sell “totally green” products created from nanotechnology, wishes to scatter on land and in water its G- Marine Fuel Spill Clean-UP! (NANO Emulsion Technology) Oil Dispersant in areas affected by the BP rig collapse in the Gulf of Mexico.

The undersigned public-interest organizations respectfully urge the EPA to deny approval of this and similar projects that seek to release nanoscale chemicals or chemicals measuring less than 300 nanometers into the environment. In this case the company claims their product is composed of particles measuring 1-4nm. Manufactured nanoparticles have been shown to be toxic to humans, mammals, and aquatic life.

The argument made is that G-MARINE Fuel Spill Clean-UP! contains a nanoscale component, that nanoscale components have been shown to be toxic, therefore the dispersant should not be used.  The letter goes on to say:

We are not aware at this time of the exact nanoscale particles used in this ‘nano emulsion technology’ because this information is considered a trade secret by the company. Yet, we do know that most chemicals manufactured at the nanoscale hold unique and potentially toxic properties. While some new properties from the nanoscale may seem desirable, materials at this scale can also pose new toxicological risks. Nanoparticles have a very large surface area which typically results in greater chemical reactivity, biological activity and catalytic behavior compared to larger particles of the same chemical composition. Unfortunately, the greater chemical reactivity and bioavailability of nanomaterials may also result in greater toxicity of nanoparticles compared to the same unit of mass of larger particles. Other properties of manufactured nanomaterials that influence toxicity include: chemical composition, shape, surface structure, surface charge, catalytic behavior, extent of particle aggregation or disaggregation, and the presence or absence of other groups of chemicals attached to the nanomaterials.

Unfortunately, the letter falls into the all too common trap of mistaking a relatively unstable cluster of small molecules as a “nanoparticle,” and prejudicially tagging it with properties associated with very specific nanoparticles – many of which are unlikely to have any relevance here.

This is a serious mistake to make, as it undermines any science-based discussion of safety and risk by claiming the ingredient in question is something it is not, then inferring properties on it which it is unlikely to have.  And the danger here is that as soon as the science is taken out of the equation, the real likelihood of harm being caused becomes extremely difficult to address.

Then there is the AOL piece.

In the main, the piece is straight reporting of the situation – albeit with an emphasis on the nano-safety issue.  But one section in particular jumps out:

The report of the possible use of nano-dispersants has outraged Harbut, who heads the Environmental Cancer Initiative at Michigan’s Karmanos Cancer Institute.

“A decision to use nanoparticle-based dispersants in the gulf is less an engineering or environmental decision, but more a public health and individual patient care issue. As does asbestos, nanoparticles have been shown to cause an aggressive cancer called mesothelioma,” he said.

And like asbestos in its early usage, human health effects of exposure, ingestion or breathing of nanoparticles have been rarely observed, let alone studied.

“To dump tons of nanoparticles into the food and respiratory cycle in this manner is irresponsible,” Harbut told AOL News

Here, the conflation between nanoscale micelles, nanoparticles and mesothelioma is wrong and it is irresponsible.  Nanoparticles in general have not been shown to cause mesothelioma, neither is there any theory to suggest that they might – this is pie in the sky speculation.  Carbon nanotubes – a specific form of nanomaterial – might possibly be associated with the disease under some conditions, but this is still uncertain.  But carbon nanotubes are not what may would recognize as nanoparticles, and are certainly not the same as micelles.

Then there is the conflation between micelles and nanoparticles again.  Okay so technically a micelle might be likened to a nanoparticle – but in the same way a soap bubble might be likened to a soccer ball!

So where does this leave us?

The root of the problem here seems to have been Green Earth Technologies’ use of the term “nano” – if they had just talked about micelles, no red flags would have been raised and it’s unlikely that the NGO letter would have found its way to EPA.  This term clearly term led to some confusion amongst organizations sensitized to the word.

Nevertheless, it would be irresponsible to throw the safety concerns out simply because of a definitional technicality.

Nanoscale materials do raise new safety questions – including nanoscale micelles.  But often, these questions can be addressed to a reasonable degree.  I’m not going to defend the safety evaluations that have been made by Green Earth Technologies as I don’t have the data.  In fact the company possibly shoots itself in the foot by being rather optimistic about the safety of their product.  This appeared today in an open letter from the company for instance:

Does G-MARINE OSC-1809 Oil & Fuel Spill Clean-UP! have any adverse affects on humans / animals or the environment?

None whatsoever. G-MARINE OSC-1809 Oil & Fuel Spill Clean-UP! has shown absolutely no adverse effect on humans or animals. All of our Marine products are manufactured from ingredient LISTED ON THE EPA CLEAN INGREDIENTS (1) List. It has a zero OHSA hazard rating and in Lab Tests (2) it has been shown to have no adverse affects whatsoever to nose (inhalation), mouth (ingestion), ears, skin, or eyes. Even if the person is subjected to a concentrated overdose, there has been no noticeable adverse affect. The Micelles BECAUSE of the EXTREMELY SMALL SIZE do NOT persist in the environment and Bio-degrade into harmless elements in 10 days as per EPA guideline in the CLEAN INGREDIENTS list.

“None whatsoever” is a dangerous assertion to make on adverse effects, as it implies every possible test has been done, and every conceivable eventuality accounted for.  And people tend to be suspicious of such absolute statements – better to be honest and admit the bounds of current knowledge.  Yet it is reasonable to assume that small micelles made up of well-evaluated ingredients are unlikely to have long-term environmental impacts that go beyond that of these ingredients – mainly because the micelles will break up and release their constituent components reasonably rapidly.

Could they get to places where they can cause harm in the short term because of their size?  It’s possible – and I would hope that toxicity tests would at least indicate whether this is an issue.  But there is a danger of making up potential yet implausible harm scenarios here because of a misunderstanding of the differences between micelles and other forms of nanomaterials.

And this is perhaps the most important message to come out of this situation.  In the case of the Gulf oil spill, inaction is not an option – but informed action must be based on the best possible information rather than questionable speculation.  This places the onus on companies to get the safety testing on their products right, even if it means going above and beyond what they consider necessary (especially if they decide to use a loaded term like “nano”).  It means that regulators need to ready to move fast when questions like this are asked – delayed action or misinformed action both have the potential to lead to adverse consequences.  And it also means that organizations and individuals influencing the debate and the decisions made must make sure they get the science right – speculative fear can only be divisive.

Making wise choices on the dispersants used in the Gulf of Mexico is vitally important, and bad choices could have lasting consequences.  And it is right and proper that questions should be asked over the use of one product over another.  But if the spill is to be dealt with effectively, these choices must be science-informed – otherwise no-ones interests are served in the long run.

]]> http://2020science.org/2010/05/28/nano-dispersants-and-nano-hysteria-time-to-think-about-the-science-folks/feed/ 24 http://2020science.org/2009/12/17/kimbrell/ http://2020science.org/2009/12/17/kimbrell/#comments Thu, 17 Dec 2009 18:00:38 +0000 Guest http://2020science.org/?p=2655

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).

Part 7 of a series on rethinking science and technology for the 21st century

Yesterday, I listened to respected economists discussing geoengineering; gave a Skype interview on nanotechnology from the comfort of my own home; and watched as reactions to Michael Jackson’s death spread through virtual web-based communities.  Twenty years ago, when Jackson was at the height of his artistic powers, such a day would have been the stuff of science fiction.  Now, it’s just business and usual.

Looking back over the past two decades, it’s easy to see how Coupling, Communication and Control have changed the world we live in.  The impact of CFC’s on the ozone layer, the looming global warming crisis and the associated acidification of oceans are all testaments to how recent human actions are increasingly coupled to global environmental re-actions.  Technological advances built on the back of our increasing control over matter – whether living or non-living – have led to profound changes in what we can achieve as a species.  And the global communications revolution – from the rise of the internet to the emergence of social media – continues to bend previously rigid social, commercial and geographical boundaries.

Yet important as the changes associated with each of these individual “C’s” are, it is at their intersection that their true transformative nature is revealed.  This is where ideas and influences spark off each other, leading to transformative leaps in innovation and impact…

To some extent we’re seeing this already.  Modern global communications wouldn’t be possible without a whole raft of technological breakthroughs.  Our impact on the environment is driven as much by our technologies and associated resource demands as by a growing world population, while solutions to the resulting consequences are technology-driven more often than not.  And worldwide responses to global issues are being facilitated by increasingly sophisticated communications media.

As the overlap and integration between each of the three “C’s” grows, the rate of innovation is likely to accelerate.  Yet the place where the really transformative stuff will occur is going to be at the center – at the confluence of advances in Coupling, Communication and Control.  This is where we can expect game-changing innovations that make the impossible possible.  It’s also where we are likley to see new technologies and ideas emerge that are potentially beyond our collective ability to handle with any degree of maturity.

And this brings us to the key science and technology-driven challenge we face as we head further into the twenty first century:  How are we going to handle the powerful and transformative new opportunities and dangers arising from this confluence of coupling, communication and control, without messing things up?

In contrast to the rapid developments likely at this nexus of the three “C’s,” the inertia inherent in established institutions and ideas will resist change.  And so unlike some, I don’t think we will  adapt naturally to the challenges that are coming. Yet the result of ignoring them, assuming they are someone else’s problem, or trying to shoehorn them into outmoded ways of doing business, will most likely be social, economic and political collapse.

The alternative is to take a long hard look at what needs to be done in order to ride the coming wave rather than be engulfed by it.  From twenty years ago, today’s world would look familiar yet different.  Given the current rate of change, I suspect that the world twenty years  from now will be unrecognizable.  If we’re going to cope with the changes that are coming, we will need to learn how to change with them.  And one of the first places to start will be the policies that guide the science and technology that are driving – and will help navigate – this confluence of coupling, communication and control.

Next time: Riding the wave: Rethinking science & technology policy

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: Nanoscale control: Leveraging biology

Next: Riding the wave: Rethinking science & technology policy

If there’s one thing that’s guaranteed to unite global warming “denialists” on both sides of the aisle, it’s geoengineering – the intentional planet-wide manipulation of the environment.  At least, you might be left with that impression after reading the comments following a thoughtful piece in Monday’s Wall Street Journal by Jamais Cascio.

It’s Time to Cool the Planet. Wall Street Journal. Credit: Viktor Koen

Cascio describes himself as a “reluctant advocate” of geoengineering.

“Many of us who have been watching this subject closely have gone from being skeptics to advocates. Very reluctant advocates, to be sure, but advocates nonetheless.”

Fraught with uncertainty and risk as geoengineering is, he argues that cutting greenhouse gas emissions will not be sufficient in the short term to curb the impacts of global warming.  Rather, direct intervention is necessary to give us a bit of breathing space.

Interestingly, he does not advocate geoengineering as a technical fix to a manmade problem.  He goes to great pains to stress that he believes reducing greenhouse gas emissions is the only long-term solution to the impact of human activities on climate change.  But geoengineering could give us more time to come up with workable solutions to achieving this.

“What geoengineering can do is slow the increase in temperatures, delay potentially catastrophic “tipping point” events—such as a disastrous melting of the Arctic permafrost—and give us time to make the changes to our economies and our societies necessary to end the climate disaster.

“Geoengineering, in other words, is simply a temporary “stay of execution.” We will still have to work for a pardon.”

Cascio also does not shy away from the potential risks as well as the social and political challenges associated with such direct action.

“Any kind of geoengineering would also face other issues. Most prominent are the political concerns. Since geoengineering is global in its effects, who determines whether or not it’s used, which technologies to deploy, and what the target temperatures will be? Who decides which unexpected side effects are bad enough to warrant ending the process? Because the expense and expertise required would be low enough for a single country, what happens when a desperate “rogue nation” attempts geoengineering against the wishes of other states? And because the benefits and possible harm from geoengineering attempts would be unevenly distributed around the planet, would it be possible to use this technology for strategic or military purposes? That last one may sound a bit paranoid, but it’s clear that any technology with the potential for strategic use will be at the very least considered by any rational international actor.

“There are also more mundane questions of liability. If, for example, South Asia experiences an unusual drought during cyclone season after geoengineering begins, who gets blamed? Who gets sued? Would all “odd” weather patterns be ascribed to the geoengineering effort? If so, would the issue of what would have happened absent geoengineering be considered relevant?”

Yet at the end of the day, he believes that, despite the very real problems associated with taking direct action, the alternatives are worse.

This is a finely written piece, and well worth reading.  It lays out the pros and cons of geoengineering in a carefully reasoned way.  It doesn’t contain much science admittedly.  But then I wouldn’t expect it to – it’s an opinion piece, and the supporting science isn’t that hard to track down.

The article also spotlights what I suspect is going to be the biggest challenge to any effective use of geoengineering – getting a disparate bunch of people across social political and geographical boundaries to work together.  I fear that, while we now have the beginnings of technologies to tackle global problems, our mindset remains too parochial to implement them wisely.  Constrained by outmoded ways of thinking and acting, we are simply too immature as a species to make good decisions on a global scale.

The answer is deceptively simple – we need to grow up.  This won’t be easy.  I’m not even sure it is possible – which doesn’t bode well for humanity.  But if we don’t find ways of making wise decisions on technology uses that potentially affect everyone, things are going to get messy.

Perhaps climate change and the threat/lure of geoengineering are the jolt we need to find innovative ways of working toegther that transcend conventional boundaries and blinkered perspectives.  I don’t know.

I do know though that progress won’t happen without innovative thinking, open dialogue and a little humility on all sides.  Jamais Cascio’s piece offers the hope that these challenges, although complex, are not beyond our reach; if only we can tackle them with the maturity they demand.

Sadly, the comments on the Wall Street Journal piece suggest we still have a lot of growing up to do.

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/ 28 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

Part 2 of a series on rethinking science and technology for the 21st century

In the previous post in this series I introduced the idea of the three “C’s:” Coupling Communication and Control—three factors that together challenge conventional ideas on how science and technology are best developed and used within society.  Following on from that introduction, I want to focus more closely on the first of these: Coupling.

I haven’t actually got much to say here that is new or unfamiliar—most of the new stuff will probably come when I reach the third “C”—Control.  In fact, the concepts buried in the idea of coupling are somewhat obvious.  But that doesn’t make them any less significant.

Very simply, coupling refers to the interconnectedness between society’s actions and global environmental re-actions…

Up until recently, it was assumed that the world was so large, and humanity so small, that whatever we did would simply be absorbed by the Earth.  Oceans, the atmosphere, the planet, were so massive that at worst our actions would cause minor blips in the system, which would dissipate over time.

We now know that this is not the case.  There is a complex dynamic between people and the Earth that has existed for millennia.  But this coupling wasn’t  apparent while the global population was relatively low and resource demands less excessive.

In the past, the lag between human actions and environmental reactions tended to be long and resulting changes gradual. This is no longer the case.  The global population will hit 7 billion people in a few years—fifty years ago it was less than half this.  And resource demands per capita have rocketed while supplies have not, meaning that today’s 6 billion people are stressing the system to a far greater extent than a mere doubling of the population would suggest.

The result is a closer coupling between out actions and the Earth’s reactions than ever before in the history of humanity.  The current implications of this ever-closer coupling are clear, and include all the usual suspects:  Increasing global pollution, acidification of the oceans, rising CO2 levels, global warming.

This coupling is getting stronger, the time lag between actions and responses is getting shorter, and the challenges of predicting and responding to society-induced changes are getting increasingly complex.

And because we are part of the system, these global changes are in turn affecting us—coupling works both ways.

Basic physics provides a simple illustration of this.  I was in two minds about showing the video below because, lets face it, its less than polished (you’ll see what I mean if you watch it).  But it does illustrate the coupling issue rather neatly—as long as the analogy isn’t stretched too far.

Coupled oscillators as an illustration of coupling between society and the Earth

What you see are a pair of coupled oscillators—cobbled together from garden twine and two Orangina bottles.  Together, they demonstrate a physics phenomenon where energy is transferred back and forth between two identical oscillating systems—pendulums in this case.

The experiment starts off with just one of the pendulums swinging.  The second seems to barely move, no matter what the first does.  But over time, the second pendulum begins to be affected by the first one, and starts to oscillate with ever-larger swings.  Then as the second pendulum gets into its stride, it begins in turn to drive the first one.  And so the cycle goes.

The analogy to humanity and the Earth is obvious.  Our actions have seemed inconsequential in the past, but they inevitably lead to environmental re-actions.  These in turn end up impacting back on us.  The analogy does fall apart rather quickly if pushed too far.  But it’s a useful reminder that there is two-way feedback between our actions and the environment we live in, and that over time our actions come back to haunt us unless we proceed with care.

This coupling is cumulative, it is non-linear, and it is increasing rapidly as our demands on the planet grow.  Which means that the consequences of what we do, and the global impacts of those consequences, are becoming harder to predict and control.

Managing this coupling will take all of our skill, and will not be possible without significant advances in science and technology.  Which is why no discussion of science and technology and their role in society can afford to neglect it.

But the story doesn’t end there.  Growing global demands are strengthening the coupling between people and the planet.  But other factors are also playing into this complex relationship; magnifying the challenges emerging in an already serious situation.  One of these factors is the rapid evolution of global communications systems, which is shaking up how information and ideas flow around the globe.

This virtual coupling between people will be the focus of the next post in this series.

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: Science, technology and the three “C’s:” Communication, Coupling and Control

Next: Communication: Science and technology in a connected world

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.

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.

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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!

The blogging community is no stranger to the use (and possible abuse) of nanometre-scale silver—products ranging from silver-enhanced socks and toothpaste to plush toys and cure-alls have all appeared in the spotlight recently. With each passing month, the number of nano-silver gizmos on the market is growing.

Back in March 2006 when the Project on Emerging Nanotechnologies Consumer Products Inventory was launched, there were 25 products claiming to use nanoscale silver. In contrast, the August 2008 update of the inventory brought the number of nano-silver containing products to 235—an increase of nearly ten times over two and a half years!

This fashion for a splash of silver in consumer products has quite naturally led to questions being asked—how much silver is being used, where does it go, and what harm does it do (if any) when it gets there? Unfortunately, answers to these questions have been less than forthcoming; leading to a lot of speculation and rather less science in the ensuing discussions. But this is hopefully about to change…

Some time ago, the Project on Emerging Nanotechnologies asked Dr. Sam Luoma—an internationally respected expert on silver in the environment—to turn his thoughts to the possible impacts of nano-silver. The result—just published—is a thorough exposition of what is known about silver in the environment, how this applied to nanoscale silver, what new potential challenges the use of nano-silver raises, and how these challenges might be addressed.

The report (available here. PDF, 1.1 MB), which includes a highly recommended foreword by J. Clarence Davies on the policy implications arising from Sam’s science-based analysis, is probably the most comprehensive assessment to date of the current state of knowledge on silver and nano-silver in the environment. By my reckoning it covers everything you ever wanted to know about silver, and then some…

Luoma starts off by looking at what is already known about silver in the environment; what happens to it, where it accumulates, its bioavailability, and its toxicity. He then goes on to ask how much of this can be applied to nanoscale silver, and where the nanoscale form of the material leads to new behaviour and new challenges.

The discussion follows a logical progression, using the “source-pathway-receptor-impact” principle for risk assessment suggested by Richard Owen and Richard Handy in 2007 (PDF, 428 KB). In essence, this deals with the questions:

• Where does the silver come from?
• Where does it go and how does it get there?
• What is exposed to it? And
• What happens then?

This turns out to be a smart move, because when the discussion moves from silver (about which we know quite a bit) to nanoscale silver (about which we know not a lot), a clear framework has been established for thinking about where nano-silver can probably be treated as other forms of silver, where its “nano-ness” likely leads to shifts in behaviour away from the established baseline, and where the critical data gaps and challenges lie.

This is a report that has to be read from cover to cover to get the full flavour of Luoma’s analysis. Fortunately, the 60 pages (72 with foreword, appendix and references) are written in a highly accessible style—never have marine clams been so engaging! However, here are a few things in particular that struck me as I read through the work:

• First, Sam eloquently establishes that we know a lot about silver in the environment; we are not starting from zero knowledge, but have a solid baseline from which to build on. This is a timely reminder that dealing with nanotech risks will often mean building on existing knowledge, rather than starting from scratch.

• Second, the physical, chemical and biological behaviour of silver in the environment is complex—this is not a substance that can be dealt with through sweeping generalizations. The transport, bioavailability and toxicity of the material depends to a significant degree on the chemistry of the environment it is within, and the potential to cause harm may decrease as well as increase depending on this environment. There is no reason to believe that things get any simpler when dealing with nanoscale silver.

• Third, while somewhat speculative, it is possible to imagine scenarios where the distributed use and release of nanoscale silver could lead to relevant environmental loadings. In other words, just because the individual release rates from one washing machine or a single pair of nano-silver socks are extremely low, does not mean that the cumulative release rates from many nano-silver products will not be important. While I suspect that some of the usage figures in Sam’s scenarios may be on the high side of realistic, it is possible to show that the widespread use of nano-silver containing products could lead to environmental contamination levels comparable with those associated with the analogue photographic industry at its peak.

• Fourth, silver nanoparticles could conceivably act as a “Trojan horse” for getting toxic silver ions into cells—essentially increasing the toxicity of the material by transporting it to places that are normally off-limits.

• And finally, there are sufficient gaps in our knowledge over the release, fate and impact of nano-silver that, when coupled with what is known, demand strategic research into potential risks and their management at a level which currently does not exist.

But these are fleeting impressions that do not do the report justice, and are certainly no substitute for reading the report itself.

I suspect that nano-silver is here to stay—the value it adds to products is too real to ignore. But its safe use will depend on grappling with the new challenges it presents. And Luoma’s report provides what is probably the most thorough resource to date for identifying these challenges, and developing a plan of action for dealing with them.

Clearly, essential reading for anyone with a stake in ensuring a responsible and successful nano-silver business!

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Notes

The report “Silver Nanotechnologies and the Environment: Old Problems or New Challenges?” (PEN 15) is freely available at www.nanotechproject.org/publications/archive/silver/

In the spirit of full disclosure, I could be accused of having a biased perspective on this report; having worked closely with Sam through its development. So you probably shouldn’t take too much notice of me when I claim that this is a seminal report on nano-silver in the environment, and one that is destined to become the reference work in the field for some years.

Sam’s report is augmented by a database of silver nanotechnology used in commercial products, published on the Project on Emerging Nanotechnologies website (available here). This was compiled by Emma Fauss at the University of Virginia, and complements the PEN Consumer Product Inventory by including more extensive information on the use of nanoscale silver in products.

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This post first appeared on the SAFENANO blog in September 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