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Nano technology & potential hazards

Written By Gopal Krishna on Sunday, October 26, 2008 | 10:14 AM

In a report released in April, 2008 the Planning Commission of India recommends nanotechnology research and development (R&D) should become one of six areas for investment.

The commission recommends policies to and carries out financial planning for government departments. The report was written by a subgroup of the commission, and will be incorporated into India's eleventh five-year plan, for 2007–2012.

The authors recommend ways to harness nanotechnology, biotechnology and bioinformatics to transform Indian agriculture, including creating a national institute of nanotechnology in agriculture.

P.S:

RACHEL'S ENVIRONMENT & HEALTH NEWS #816
http://www.rachel.org
April 28, 2005
Published May 5, 2005
Nanotechnology and the Precautionary Principle
By Peter Montague
Nanotechnology -- or nanotech, for short -- is a new approach
to industrial production, based on the manipulation of things
so small that they are invisible to the naked eye and even to
most microscopes.
Nanotech is named for the nanometer, a unit of measure, a
billionth of a meter, one one-thousandth of a micrometer. The
Oxford English Dictionary defines nanotechnology as "the branch
of technology that deals with dimensions and tolerances of less
than 100 nanometers, especially the manipulation of individual
atoms and molecules." Nanotech deals in the realm where a
typical grain of sand is huge (a million nanometers in
diameter). A human hair is 200,000 nanometers thick. A red
blood cell spans 10,000 nanometers. A virus measures 100
nanometers across, and the smallest atom (hydrogen) spans 0.1
nanometers.
In the realm below 50 nanometers, the normal laws of physics no
longer apply, quantum physics kicks in and materials take on
surprising new properties. Something that was red may now be
green; metals may become translucent and thus invisible;
something that could not conduct electricity may now pass a
current; nonmagnetic materials may become magnetized; insoluble
substances may dissolve. Knowing the properties of a substance
in bulk tells you nothing about its properties at the nano
scale, so all nano materials' characteristics -- including
hazardous traits -- must be learned anew by direct experiment.
Nanotechnologists foresee a second industrial revolution
sweeping the world during our lifetimes as individual atoms are
assembled together into thousands of useful new products. Few
deny that new products may entail new hazards, but most
nanotechnologists say existing regulations are adequate for
controlling any hazards that may arise. In the United States,
nanotech is not now subject to any special regulations and nano
products need not even be labeled. Furthermore, no one has
developed a consistent nomenclature for nano materials, so
rigorous discussion of nanotech among regulators and
policymakers is not yet possible. Without consistent
nomenclature, standardized safety testing lies in the future.
No one denies that nanotech will produce real benefits, but,
based on the history of nuclear power, biotechnology and the
chemical industry, skeptics are calling for a precautionary
approach. The resulting clash of philosophies -- "Better safe
than sorry" versus "Nothing ventured, nothing gained" or even
in some cases "Damn the torpedoes, full speed ahead!" -- may
offer a major test of the Precautionary Principle as a new way
of managing innovation.
"WORLD PEACE, UNIVERSAL PROSPERITY"
The pressure for rapid development of nanotech is enormous. The
surprising properties of materials at the nano scale have
opened up a new universe of industrial applications and
entrepreneurial dreams. Largely unnoticed, hundreds of products
containing nano-sized particles have already reached the market
-- metal surfaces and paints so slick they clean themselves
when it rains; organic light-emitting diodes for computer
screens, digital cameras and cell phones; sub- miniature data
storage devices (aiming to hold the Library of Congress in a
computer the size of a sugar cube); specialty lubricants; long-
mileage vehicle tires; nano-reinforced plastics for stronger
automobile fenders; light-weight military armor;
anti-reflective and scratch-resistant sun glasses;
super-slippery ski wax; powerful tennis rackets and
long-lasting tennis balls; inkjet photographic paper intended
to hold an image for 100 years; high-contrast MRI scanners for
medical diagnosis; efficient drug and vaccine delivery systems;
vitamins in a spray; invisible sunscreen ointments containing
nano particles of titanium or zinc; anti-wrinkle cosmetic
creams; and so on.
And this is just the beginning. Nanotech wasn't possible until
the invention in the 1980s and early 1990s of ways to arrange
individual atoms under software control. Nano particles,
nanotubes and carbon nano crystals called Bucky Balls (after
Buckminster Fuller) are now being manufactured in ton
quantities for industrial use. Currently technologists are
working feverishly to coax nature's most successful nano
factory, the living cell, to grow useful new nano assemblies.
It is no exaggeration to say that the field of nanotech is
gripped by something approaching a gold rush mentality.
Worldwide, governments are spending an estimated $3 billion per
year on nanotech research, and the private sector is thought to
be spending at least that much. The U.S. government alone will
spend at least $3.7 billion on nano R&D during the next four
years. The global market for nano products is expected to reach
$1 trillion in 10 years or less. Any day of the week you can
check in at http://nanotech-now.com and catch a glimpse of the
gold rush in action.
But for some prominent proponents of nanotech, this is about
more than money -- it is about reinventing the entire world,
including humans, as they now exist. According to the U.S.
National Science Foundation, nanotechnology is the foundation
stone of NBIC -- a revolutionary convergence of nanotech,
biotech (manipulation of genes), info tech (computers), and
cogno tech (brain function). In a report sponsored by the
National Science Foundation and the Department of Commerce, the
technologists and politicians who are promoting this revolution
say it is "essential to the future of humanity" because it
holds the promise of "world peace, universal prosperity, and
evolution to a higher level of compassion and accomplishment."
They say it may be "a watershed in history to rank with the
invention of agriculture and the Industrial Revolution." The
ultimate aim of this revolution has been an explicit human goal
for at least 400 years -- the "conquest of nature" and the
enhancement of human capabilities.
Whatever else it may offer, the nanotech revolution entails a
radical new approach to industrial production with the
potential to change every existing industry, plus create new
ones. Typical manufacturing today -- even construction of the
tiniest computer circuit -- relies on "top-down" techniques,
machining or etching products out of blocks of raw material.
For example, a common technique for making a transistor begins
with a chunk of silicon, which is etched to remove unwanted
material, leaving behind a sculpted circuit. This "top-down"
method of construction creates the desired product plus waste
residues.
In contrast, nanotech makes possible "bottom-up" construction
in which atoms are arranged under software control -- or in
ideal cases they will self-assemble, just as living cells
self-assemble -- into the desired configuration with nothing
left over, no waste. Instead of cutting trees into lumber to
make a table, why not just "grow" a table? Thus nanotech seems
to offer the possibility of waste-free manufacturing and
therefore a cleaner environment. Furthermore, nanotech may help
remediate past pollution. U.S. Environmental Protection Agency
(EPA) is funding research on releasing nano particles into the
environment to detoxify mountains of toxic waste remaining from
the 20th century's experiment with petroleum-based chemistry.
INSURING A NANOTECH FUTURE
Nevertheless, without denying plausible benefits, critics want
nanotech's potential problems brought into the open:
** Unless nanotechnology is shared generously, it may create a
"nano divide" similar to the "digital divide" that exists now
between those with ready access to computers and those without.
** Humans given enhanced mental or physical capabilities may
gain great advantage over normal people. On the other hand,
some people may be coerced to accept dubious or unwanted
enhancements.
** Inequalities within and between nations may be exacerbated
if individuals and corporations gain monopoly control of
nanotech by patenting the building blocks of the universe -- a
precedent set in 1964 when Glenn T. Seaborg was issued a patent
on an element he discovered and named Americium.
In the longer term, some leading technologists like Ray
Kurzweil, inventor of the first reading machine for the blind,
and Bill Joy, one of the founders of Sun Microsystems, fear
that nanotech will give individuals -- inadvertently or
intentionally -- destructive potential greater than the power
of atomic weapons. As Joy wrote in 2000, "I think it is no
exaggeration to say we are on the cusp of the further
perfection of extreme evil, an evil whose possibility spreads
well beyond that which weapons of mass destruction bequeathed
to the nation-states, on to a surprising and terrible
empowerment of extreme individuals."
Others, such as the insurance industry, have more mundane
concerns about nanotech -- chiefly, the potential health and
environmental hazards of tiny particles. In May of 2004, Swiss
Re, the world's second-largest reinsurance firm, issued a
report calling for the Precautionary Principle to guide
nanotech development. Swiss Re itemized a host of potential
problems that it says need to be resolved before nanotech
products are fully deployed, including these:
** One of the new properties of nano-sized particles is their
extreme mobility. They have "almost unrestricted access to the
human body," Swiss Re points out, because they can enter the
blood stream through the lungs and possibly through the skin,
and seem to enter the brain directly via olfactory nerves. Once
in the blood stream, nano particles can "move practically
unhindered through the entire body," unlike larger particles
that are trapped and removed by various protective mechanisms.
** If they become airborne, nano particles can float for very
long periods because -- unlike larger particles -- they do not
readily settle onto surfaces. In water, nano particles spread
unhindered and pass through most available filters. So, for
example, current drinking water filters will not effectively
remove nano particles. Even in soil, nano particles may move in
unexpected ways, perhaps penetrating the roots of plants and
thus entering the food chains of humans and animals.
** One of the most useful features of nano particles is their
huge surface area. The smaller the particle, the larger its
surface in relation to its mass. A gram of nano particles has a
surface area of a thousand square meters. Their large surfaces
give nano particles some of their most desirable
characteristics. For example, drug-coated nano particles may
one day transport pharmaceuticals directly to specific sites
within the human body. Unfortunately, their large surface also
means that nano particles may collect and transport pollutants.
Furthermore, their large surface means nano particles are
highly reactive in a chemical sense. As Swiss Re noted, "As
size decreases and reactivity increases, harmful effects may be
intensified, and normally harmless substances may assume
hazardous characteristics." Nano particles may harm living
tissue, such as lungs, in at least two ways -- through normal
effects of chemical reactivity, or by damaging phagocytes,
which are scavenger cells that normally remove foreign
substances. Phagocytes can become "overloaded" by nano
particles and cease functioning. Worse, overloaded phagocytes
retreat into deeper layers and so become unavailable to protect
against foreign invaders. Successive particles are then able to
do their full reactive damage, and other invaders, such as
bacteria, may penetrate unhindered. The surface reactivity of
nano particles gives rise to "free radicals," which are atoms
containing an "unsatisfactory" number of electrons (either too
few or too many for stability). Free radicals swap electrons
with nearby atoms, creating further instabilities and setting
off a cascade of effects. Free radicals give rise to
inflammation and tissue damage, and may initiate serious harm,
such as growth of tumors. On the other hand, some free radicals
are beneficial, destroying invaders. So the role of nano
particles in producing free radicals remains to be clarified.
** Nano particles would normally tend to clump together,
forming larger, less dangerous particles -- but
nanotechnologists take pains to prevent clumping by adding
special coatings. As a result, nano particles in many
commercial products, sprays and powders remain reactive and
highly mobile.
** Whether nano particles can pass through the skin into the
blood stream is the subject of intense debate. Different
experiments have yielded conflicting results, presumably
because test protocols have not been standardized. Some believe
that nano particles may slip between the layers of outer skin
and penetrate through to the blood below. Others believe that
hair follicles offer a direct route for nano particles to
penetrate from skin to blood. No one knows for sure. Despite
this knowledge gap, sun screens, skin lotions and baby products
containing nano particles are already on the market. Clearly
this is a problem for insurance firms providing liability
coverage. Swiss Re says, "Considering the wide variety of
products already on the market, the need for a solution is
urgent."
** Ingested nano particles can be absorbed through "Peyer's
plaques," part of the immune system lining the intestines. From
there, nano particles can enter the blood stream, be
transported throughout the body, "and behave in ways that may
be detrimental to the organism," Swiss Re notes. While in the
blood stream, nano particles have been observed entering the
blood cells themselves.
** Once in the body, nano particles can enter the heart, bone
marrow, ovaries, muscles, brain, liver, spleen and lymph nodes.
During pregnancy, nano particles would likely cross the
placenta and enter the fetus. The specific effects in any given
organ would depend upon the surface chemistry of particular
particles, which in turn would be determined by their size and
surface coating. "It is likely that in the course of its entire
evolution, humankind has never been exposed to such a wide
variety of substances that can penetrate the human body
apparently unhindered," Swiss Re says.
** The brain is one of the best-protected of all human organs.
A guardian "blood-brain barrier" prevents most substances in
the blood from entering the brain (alcohol and caffeine being
two well-known exceptions). However, nano particles have
repeatedly been shown to pass into the brain, where their
effects are unknown. Will they accumulate and, if so, to what
effect?
** Nano particles may disrupt the immune system, cause allergic
reactions, interfere with essential signals sent between
neighboring cells, or disrupt exchanges between enzymes, Swiss
Re says. Some of these characteristics may be harnessed for
benefit -- for example, in experiments a carbon nano crystal
has been able to disrupt one of the processes that allows the
AIDS virus to multiply.
** Nano particles in disposable products will eventually enter
the environment. In the environment, nano particles represent
an entirely new class of pollutants with which scientists (and
nature) have no experience. Swiss Re speculates that, "Via the
water cycle, nano particles could spread rapidly all over the
globe, possibly also promoting the transport of pollutants."
Swiss Re asks, "What would happen if certain nanoparticles did
exert a harmful influence on the environment? Would it be
possible to withdraw them from circulation? Would there be any
way of removing nanoparticles from the water, earth, or air?"
** Turning to workplace hazards, Swiss Re asks whether nano
particles will become the next asbestos. To protect workers,
effective face masks are "not a very realistic prospect at
present, since the requisite design would render normal
breathing impossible." New designs may be possible but remain
unproven.
PRECAUTION ON A SUPER-SMALL SCALE
Swiss Re notes that, in the past, the drive toward rapid
technological innovation has "prevented the introduction of the
Precautionary Principle in relation to new technologies for
more than 20 years." But now, "in view of the dangers to
society that could arise out of the establishment of
nanotechnology, and given the uncertainty currently prevailing
in scientific circles, the Precautionary Principle should be
applied whatever the difficulties," Swiss Re asserts. "The
Precautionary Principle demands the proactive introduction of
protective measures in the face of possible risks, which
science at present -- in the absence of knowledge -- can
neither confirm nor reject."
What would precaution look like in a rapidly developing field
like nanotech? The British Royal Society and the Royal Academy
of Engineering issued a nanotech report in July 2004
recommending a series of precautionary actions, with the
following chain of reasoning:
** "The evidence we have reviewed suggests that some
manufactured nanoparticles and nanotubes are likely to be more
toxic per unit mass than particles of the same chemicals at
larger size and will therefore present a greater hazard."
** "There is virtually no evidence available to allow the
potential environmental impacts of nanoparticles and nanotubes
to be evaluated."
** Therefore, "the release of nanoparticles to the environment
[should be] minimized until these uncertainties are reduced."
** And, "until there is evidence to the contrary, factories and
research laboratories should treat manufactured nanoparticles
and nanotubes as if they were hazardous and seek to reduce them
as far as possible from waste streams."
These recommendations reverse the traditional approach to
industrial materials, which have historically been assumed
benign until shown otherwise.
The Royal Society puts the burden of producing information
about safety on industry, not on the public: "A wide range of
uses for nanotubes and nanoparticles is envisaged that will fix
them within products.... We believe that the onus should be on
industry to assess ... releases [of nano particles from
products] throughout a product's lifetime (including at the
end-of-life) and to make that information available to the
regulator." From such a recommendation, it is a very short step
to the European Union's precautionary proposal for industrial
chemicals, called REACH (Registration, Evaluation and
Authorization of Chemicals), which is often summarized as, "No
data, no market."
The Royal Society recommended that the use of zinc oxide nano
particles and iron oxide nano particles in cosmetics should
"await a safety assessment" -- in other words a moratorium on
these products is recommended. Likewise, "the release of free
manufactured nanoparticles into the environment for [pollution]
remediation (which has been piloted in the USA) should be
prohibited until there is sufficient information to allow the
potential risks to be evaluated as well as the benefits."
The Precautionary Principle is sometimes called the foresight
principle. Importantly, the Royal Society's report fully
embraces foresight for nanotechnology (and all other new
technologies): "Our study has identified important issues that
need to be addressed with some urgency" and so it is
"essential" for government to "establish a group that brings
together representatives of a wide range of stakeholders to
look at new and emerging technologies and identify at the
earliest possible stage areas where potential health, safety,
environmental, social, ethical and regulatory issues may arise
and advise about how these might be addressed." The group must
provide "an early warning of areas where regulation may be
inadequate for specific applications of these technologies."
And, finally, "The work of this group should be made public so
that all stakeholders can be encouraged to engage with the
emerging issues."
Thus nanotech is sparking not only a new industrial revolution
but demands for a reversal of traditional approaches to
managing innovation and a turn toward precautionary action.
Whether the momentum gathering behind the precautionary
approach can redirect the charge behind nanotech -- a
confluence of government and technophile advocates in alliance
with an emerging industrial lobby -- remains uncertain.
==========
This article originally appeared in The Multinational Monitor
Vol. 25, No. 9 (September, 2004), pgs. 16-19, under the title,
"Welcome to NanoWorld: Nanotechnology and the Precautionary
Principle Imperative."

The report says nanotechnology such as nano-sensors and nano-based smart delivery systems could help ensure natural resources like water, nutrients and chemicals are used efficiently in agriculture. Nano-barcodes and nano-processing could also help monitor the quality of agricultural produce.

The report proposes a national consortium on nanotechnology R&D, to include the proposed national institute and Indian institutions that are already actively researching nanotechnology.

It also recommends that Indian universities and institutions develop suitable graduate and postgraduate programmes to train young scientists in nanotechnology.

Vandana Dwivedi, coordinator of the subgroup and an advisor in the Planning Commission, says implementing all the report's recommendations will take time, though she hopes to see some of the aspects rolled out in the 2007–2012 five-year plan. No specific initiatives on nanotechnology have yet been announced.

As nano technology (engineered particles of an extremely small size) is developing rapidly, issues on occupational and environmental health are just beginning to emerge on this subject.

Recent studies have shown that nano particles can enter the human body and interfere with cellular as well as physiological functions.
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