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Vol.
XXVII No. 31
August 3,
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Nanotechnology:
The Genie Is Out Of The Bottle
Prabir
Purkayastha
EVERY
few years, a new hype fuels another stock market explosion. If it was
microelectronics, the Internet and biotechnology earlier, it is now the turn of
nanotechnology. And along with the hype, as it inevitably happens, we have the
naysayers who point out the unproven nature of the technology and its possible
disastrous consequences. Nanotechnlogy is no exception. The investment gurus,
unemployed after the dotcom balloon burst, are again seeking to revive the greed
machine and the moribund tech stock market by singing hallelujah to
nanotechnology. Forget yesterdays collapse of the tech stocks, nano is the
new king and will give you returns beyond your wildest dreams; be a millionaire
in your mid-twenties and then retire; the dotcom dream is back in a new package.
Along with, it we have the fear of nanotechnology turning rogue and converting
the whole world to a uniform grey goo and eliminating all life. It is not just a
few loonies and fringe groups, the grey goo fear was first propounded by Bill
Joy the co-founder of Sun Microsystems about the possibility of nana sized
robots (or nanobots) taking over the world.
Nano
is 10-9 and a nanometre is a billionth of a metre. Nanoscience refers
to study of small objects whose dimensions are of the order of ten to hundred
nanometres (10-9 metres): a nanometre is equal to 10 hydrogen atoms
lined up in a row; a white blood cell is huge by comparison: it is 10,000
nanometres in diameter. We would reach 1 millimetre if we lined up 100 such
white blood cells. In human dimensions, one nanometre is 75,000 times smaller
than the width of a hair.
WHAT
IS
NANOTECHNOLOGY
Nano
technology is the use of either materials or construction of atomic scale
machines for specific purposes.
While
atomic scale machines are still far away, the use of nano sized particles or
nano tubes are already seeing many applications. They have entered sunscreens,
tennis balls and rackets, stain proof textiles, and even as coatings for sinks
and toilets. The next few years are likely to see an explosion of new materials
entering various consumer products as designers use the novel properties of nano
sized particles.
The
first nanomaterial discovered was in 1985 when researchers led Richard Samlley
at Rice University found that 60 carbon atoms could arrange themselves
symmetrically in the shape of a stitched soccer ball one nanometre across. This
was dubbed as fullerenes after geodesic domes designed by Buckminster
Fuller. They are also called as buckyballs. The buckyballs have some remarkable
properties, they were much stronger than steel and could conduct electricity and
heat. Somio Iijima later discovered the elongated version of the fullerenes
carbon nanotubes that were 100 times stronger than steel while being 1/6 its
weight.
Why
do nanomaterials have new properties than their macro-sized relatives? This is
due to the quantum phenomena that appear as the particles shrink to atomic scale
size. At the macro level, we see the laws of classical physics; below 100
nanometres, properties based on quantum physics become visible. It is in this
intersection of the classical and quantum that the nanomaterials lie. We use
additional properties based on quantum physics to deliver affects that are
visible at the macro level.
It
is the new properties of nano sized particles or tubes that offer possibilities
in their use ranging from consumer products to drug delivery. Buckyballs can be
used as free-radical scavengers; they can hold another atom within their core. A
Toronto based company is devising a series of drugs to exploit these properties.
It is, for instance, investigating the fullerene’s efficacy as an antioxidant
against neuro-degenerative disorders such as Parkinson and Alzheimer diseases.
Most candidates for drugs have poor water solubility. If they are shrunk to nano
levels, they change with higher solubility. Shrinking them can therefore
increase the range of drugs and their effectiveness.
The
new nanomaterials also offer other properties that can lead to zapping tumours,
zeroing on to specific locations in the body and so on. For instance it is
possible to have a novel drugs based on yet another nanomaterial:
three-dimensional branching structures, called dendrimers, which can be designed
as “smart devices”. These structures would have one branch identifying
a cancerous cell, a second branch containing an imaging agent, and a third
bearing a toxin to kill the cell. “That combination creates a ‘smart
bomb’,” explains Robert Paull, co-author of The Nanotech Report 2003,
“that can be programmed to a specific type of cancer cell.”
CORPORATE
INVOLVEMENT
Lux Capital a venture capital firm produced The Nanotech Report 2003 meant for investment firms. The Report brings out the huge investments that are slated for nanotechnology, particularly for new materials and in pharmaceuticals. Over 700 companies already involved in nanotechnology with 3 billion dollars proposed to be invested in 2003 worldwide. The US government funding is of the order of $2 billion since 2000 with Europe and Japan at $1 billion and $750 million respectively. Obviously the nanotech race is hotting up. Interestingly, Asian companies are particularly active in nanotechnology. Samsung followed IBM in having the largest number of nano patents. While the market for nanotechnology products is still less than a 100 million dollar, if the National Science Foundation of US is to be believed, it is set to touch $1 trillion by 2015.
The
basic concern of using nanoparticles in various applications is that whether the
properties of such material change if they are made smaller. And here the
proponents of nanotechnology are trying to claim both. On one hand, they argue
that nano has wonderful new properties that can be patented and used in a
variety of applications, and on the other they argue that as the material is
known to be non-toxic, therefore there is no need to put in a new set of
procedures for testing such nanomaterials again. The problem is that if the new
nanoparticles have wonderful new properties that make them useful, why should
not they also have harmful new properties?
A
case in point is the new sunscreen. Traditionally, zinc oxide or titanium
dioxide is used in sunscreen. As macroparticle, zinc oxide or
titanium dioxide looks white. That is why cricketers earlier had white
painted faces. Now, the new sunscreen contains nanoparticles of titanium
dioxide, which is transparent. Therefore the unsightly white paint has been
replaced by sunscreen that looks like vanishing cream. The question is whether
the new nano sized particles of titanium dioxide are chemically same as the
macro particles with the solitary exception of being transparent? For the
industry, if nanoparticles have to be tested again and new approvals taken from
the regulatory authorities, it means millions of dollars in expenditure.
Therefore, they argue that there is no need to test nanomaterials again as new
materials.
The
fear is not an idle one. Dr. Vyvyan Howard of the Developmental Toxico-Pathology
unit of the University of Liverpool (UK), in a new ETC report says, Research
is now showing that when normally harmless bulk materials are made into
ultrafine particles [nanoparticles] they tend to become toxic. Generally, the
smaller the particles, the more reactive and toxic their effect. Other
researchers have found carbon nanotubes to be highly toxic while others report
no such toxicity. Again, cell damage has been found with the use of some of
the nanomaterials, which could pose long-term problems as possible carcinogens.
ISSUE
OF REGULATION
Leading
scientists are arraigned on both sides, with the unfortunate spectacle of a
number of scientists who are commercially involved through their own companies
or their patents arguing for no new regulations. Both Drexler and V. Colvin, who
are pioneers in nanotechnology, are in favour of nano technology research and
use, have advocated stronger regulation. Drexler says, There are new
safety concerns raised by nano-particles and I believe these have not got enough
attention. Vicki L. Colvin, director of Rice University’s Centre for
Biological and Environmental Nanotechnology
(CBEN), Houston and one of the leading researchers in this area, points out “in
a field with more than 12,000 citations a year, we were stunned to discover no
prior research in developing nanomaterials risk-assessment models, and no
toxicology studies devoted to synthetic nanomaterials.”
In an interview, Colvin
cites two reasons to be concerned about nanomaterials. Because of their small
size, they may access areas of the body larger materials cannot, like healthy
cells. In addition, properties are very different at the nanometer scale. Researchers
do not know, she says, how nanomaterials are cleared from the body,
whether they are degraded, and whether they accumulate in the environment.
While
the debate between scientists is about what kind of controls are needed for
nanotechnology materials and research, The Action Group on Erosion, Technology
and Concentration, a Canadian group earlier known as RAFI and active in the GM
foods campaign, has published a paper earlier in April calling for all
nanotechnology research to be put on hold until the health risks of
ultra-fine particles can be assessed. Green Peace has also joined the debate
with also demanding that all nanotechnology research be stopped.
CONTENTIOUS
DEBATE
The
debate is even more contentious when it comes to self-replicating atomic scale
machines constructed using nanotechnology. The man who coined the phrase
nanotechnology, Eric Drexler argues that use of nanotechnology for nanomaterials
is only a marketing hype and nanotechnology definition should be much more
restrictive. Drexler says, I introduced the term nanotechnology in the
mid-1980s to describe technology based on molecular machine systems that are
able to build more molecular machine systems. (New Scientist, 29 April 03)
In this definition, nanotechnology refers to atomic scale machines that can
replicate themselves or build other machines and not atomic scale particles.
The
uses of such atomic scale machines are a myriad. They could enter our blood
stream and do complicated surgery: removal of cancerous cells, repairing various
organs and so on. They could be programmed to produce bionic devices and
therefore continue with the electronic revolution in computing. The computing
power, which is set to reach limits of micron level devices, could continue for
a few more decades with nano level technologies. However, these nano dreams have
major fears associated with technology running amuck.
If
we can build atomic scale machines that can also build more such machines, they
can become self-replicating. What is then to prevent the uncontrolled explosion
of such machines and everything being covered under a mass of nano
technologically active slime? This would result in the extinction of all life
forms with grey goo covering the entire world. Drexlers atomic machines put
the shivers up a lot of spines. Michael Crichton has written a terrifying new
best seller Prey on sentient swarm of
nanobots gone rogue. Price Charles, who earlier campaigned against Genetically
Modified foods has also voiced his concern about grey goo. In contrast, Richard
Smalley, Nobel winner in Chemistry for discovering buckyballs, holds that such
atomic level machines are impossible to construct. Smalley takes the position
that nanoscale machines are a physical impossibility because of the difficulty
of manipulating individual atoms as they stick to any surface: the “sticky
fingers problem.” In Drexlers view however, self-replicating atomic
scale machines are inevitable; if nature can do it, so can we. It is just a
matter of time.
WIDER
AREA OF
CONCERN
Obviously,
self-replicating nanobots raise a much wider area of concern than nanomaterials.
How would we ensure that their growth could be controlled when we are not able
to even contain the growth of new plant species introduced in a new environment?
Lacking the balance between preys and predators in nature has seen the explosive
growth of water hyacinth in India and rabbits in Australia. Both have become
pests that cannot be tackled easily. Obviously, even if Bill Joys grey goo
and Michael Crichton appear far-fetched, the self-replicating atomic scale
machines have enormous concerns regarding safety.
Nanotechnology
multiplies the fears of genetically modified organisms. Science is entering into
realms that allow manipulation of nature in a fundamental way. It produces
products not found in nature and therefore whose properties and long-term
consequences are not well known or difficult to predict. For the gung ho
scientists who also could be tied up to a nanotech firm, and the market gurus,
desperately in search of a new balloon to lift the stock market, nanotech is the
new Holy Grail. To others, it is the end of the world. While the need for
regulation and social control over technology is critical at a time when science
is entering into areas that have far reaching consequences, it is futile to ask
for a moratorium on nanoscience research as Greenpeace and ETC are doing.
This is not because nanomaterials and research do not need regulation and
control, but due to the inability of compartmentalising scientific research. We
cannot stop nano research unless we are prepared to stop all scientific
research.
The
domain of science does not have the simple boundaries we think it does.
Nanoscience is a combination of scientific research conducted in biological,
chemical and quantum physics domains. All these are existing disciplines. They
have been investigating quantum phenomenon and dealing with DNA strands all of
which are in the nano domain. So how do we now stop these activities, which have
been practised for decades? Do we then stop all research in these disciplines?
If not how do we charatcetise what is nano and what is not? Trying to create a
banned area in between the quantum and the macro level is impossible.
The
problem in science and technology today is that as our knowledge of nature
increases, so does our potential to do good and the bad. While earlier both were
limited, with the expansion of knowledge boundaries, both have grown enormously.
And it is not necessary that we will reap enormous benefits from each of
the knowledge boundaries we break. Just as small advances can have enormous
technological consequences and benefits. It is this new world of possibilities
and dangers that we are entering into. A heedless plunge into this could take us
down a precipice. But not developing our knowledge is also not an option. It is
like a child refusing to grow up as the world of childhood is a much more
comfortable one. And it is the adult choice of need versus gratification that we
have to make.
Finally,
the choices as a society today are distorted by capitalism. It is the urge
for unconcerned growth and profits the gratification of greed at all costs
that magnifies the danger of both biotechnology and nanotechnology. If we
allow multinational corporations and global capital driven by their greed to
take all decisions regarding safety and regulations, we are likely to face
disasters. The focus has to come back to the danger that capitalism poses to
nature and life instead of the science and technology of the nano world posing
such dangers.
