Monday, March 5, 2012

Nanotechnology: The Promise And The Peril

Nanotechnology is very intertwined with the future of all technology.  But can we disregard the potential dangers it might pose?
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One hears about amazing research involving nano technology often in the news.  We seem to be tantalized with the just-around-the-corner proclamations of dramatic improvements in efficiency, the cure of Cancer and many other dramatic advancements.  Just to cite a few examples in recent news:
  1. Nanotechnology Fabric Converts Heat To Power
  2. Physicist Create A working Transistor From A Single Atom
  3. Nanotechnology Research Could Impact Flexible Electronic Devices
  4. Nanotechnology Shrinks Conducting Wires To Atomic Scales
  5. Electronic CottonMeans Clothing Will Monitor Your Health
  6. Team Designers Bandage That Spurs, Guides Blood Vessels Growth
  7. Silicon's Possible Successors Include Carbon Nanotubes
  8. DNA Nanotechnology Could Achieve A 100 Fold Cost Reduction To Start Breaking Through Cost Barrier
  9. Researcher Creep Closer To Bionic Eye
  10. New Nano Product TO Treat Cancer Unveiled
These are just a few of the news items that range in the hundreds.  The questions that arise are two.  When will this nano revolution arrive in full swing?  Can it be trusted not to harm living things?

The Promise of Nanotechnology
There is no question in our minds that nanotechnology holds the promise to advance just about every academic discipline dramatically forwards.  The ability to be able to reduce the size of machines, motors and other designed equipment to the level of nanometers and its impact on all other disciplines of science cannot be overestimated.  Like Kathleen Cook from DiscoverNano has summarized very well,
Nanotechnology research has transformed our fundamental knowledge of the material world. Such historic developments offer extraordinary promise in translation of basic knowledge into concrete applications. Such knowledge also offers opportunities for important discussion and thoughtful critical response to public health and safety issues.
So where is it?  When will all these promises arrive in our daily lives?  Will they just filter in?  Or is there some obstacle that must be overcome before nanotechnology can become a routine factor in our daily technology, yielding dramatic advancements?

The answer is not a simple one as one would expect.  Some areas in technology will be affected first.  Others will arrive at a latter date.  An example of some of the hype though can be demonstrated from an announcement cited in 2002 in Information Week.   This article stated that Samsung was about to come out with a 32' inch flat screen computer monitor using nanotubes.  This promise has yet to be fulfilled.  And not surprisingly we find an article in Crave, titled Samsung launching carbon nanotube LCD TVs in 2011?  To our knowledge now such TVs have been produced yet.

Perhaps a good roadmap for the arrival of this technology was published by Scientific American in 2006 by Mihail Roco, titled Nanotechnology's Future.  In it Roco states that by 2015, products incorporating nanotechnology will contribute $1 trillion dollars to the global economy.  He states that this will be the first of three phases in the incorporation of nanotechnology into the world economy.  This first stage he describes as mainly dealing with what he calles passive nanostructures,
...often used as parts of a product. These can be as modest as the particles of zinc oxide in sunscreens, but they can also be reinforcing fibers in new composites or carbon nanotube wires in ultraminiaturized electronics.
The second phase which began in 2005 along with the first involves "...nanostructures that change their shape, size and conductivity and other properties during use."  Roco estimates that by 2010 "...workers will cultivate expertise with systems of nanostructures, directing large numbers of intricate components to specified ends."

The third phase according to Roco will begin in 2015 and come to full realization by 2020.  He states that,
...the field will expand to include molecular nanosystems--heterogeneous networks in which molecules and supramolecular structures serve as distinct devices. The proteins inside cells work together this way, but whereas biological systems are water-based and markedly temperature-sensitive, these molecular nanosystems will be able to operate in a far wider range of environments and should be much faster. Computers and robots could be reduced to extraordinarily small sizes. Medical applications might be as ambitious as new types of genetic therapies and antiaging treatments. New interfaces linking people directly to electronics could change telecommunications.
The Perils of Nanotechnology
Among all the promises that nanotechnology offers, there are perils.  The peril is that no one really knows that the long term effects on the environment or on living things nano particles will have.  The headlines we gathered with just a cursory look reveal the concern:
  1. Lab Raises Questions Over Nano-Particle Impact
  2. First Lawsuit On Risks Of Nanotechnology?
  3. How Healthy is Nanotechnology?
  4. Interactions of Nanomaterials With The Immune System
  5. Nanomaterial In Food Demands That Caution Be Used By Manufacturers
  6. Study Indicated That Nanoparticles Cause Brain Damage In Fish
  7. Why Carbon Nanotubes Spell Trouble For Cells
  8. The Dangers of Nanotech
  9. Government Fais To Assess Potential Dangers of Nanotechnology
  10. What Are The Possible Dangers Of Nanotechnology?
We read this startling quote from a February 12, 2012 article,
Chronic and acute oral exposure to polystyrene nanoparticles can affect iron uptake and transport in a model of human intestinal lining cells cultured in the laboratory and in a live chicken intestinal model reports a paper this week in Nature Nanotechnology. The models created in this study may provide a low-cost and high-throughput screening tool for future nanoparticle toxicity research. Because of their unique physical and chemical properties, engineered nanoparticles are used in a variety of applications, including the food industry and for drug delivery. In addition, it has been estimated that the average person in a developed country consumes over a trillion man-made fine to ultrafine particles every day. Some features of nanoparticles may, however, lead to harmful interactions with cellular material, but no studies have yet addressed the chronic effects of nanoparticle exposure on the normal function of the intestinal lining, known as the epithelium.
This concern has been voiced before. In 2011, a lawsuit was filed by the International Center For Technology Assessment.  Part of lawsuit explained,
Since 2006, numerous studies and reports, including agency publications by the Environmental Protection Agency, the Office of the Inspector General, and the U.S. Government Accountability Office, acknowledge significant data gaps concerning nanomaterials’ potential effects on human health and the environment. Most troubling are studies using mice that show that nano-titanium dioxide when inhaled and when eaten can cause changes in DNA that affect the brain function and may cause tumors and developmental problems in offspring. One study found titanium dioxide nanoparticles were found in the placenta, fetal liver and fetal brain.
Carbon nanotubes which are now being spoken about in many circles as the first major possible breakthrough, especially in medicine poses, in their present pose a danger to living cells.
It's been long known that asbestos spells trouble for human cells. Scientists have seen cells stabbed with spiky, long asbestos fibers, and the image is gory: Part of the fiber is protruding from the cell, like a quivering arrow that's found its mark. But scientists had been unable to understand why cells would be interested in asbestos fibers and other materials at the nanoscale that are too long to be fully ingested. Now a group of researchers at Brown University explains what happens. Through molecular simulations and experiments, the team reports in Nature Nanotechnology that certain nanomaterials, such as carbon nanotubes, enter cells tip-first and almost always at a 90-degree angle. The orientation ends up fooling the cell; by taking in the rounded tip first, the cell mistakes the particle for a sphere, rather than a long cylinder. By the time the cell realizes the material is too long to be fully ingested, it's too late.
This is not an insurmountable problem.  There are experiments being carried out, which by reshaping the nanotube, may remedy the problem.

But there are other issues at play here.  The way that nanoparticles behave are different from their larger counterparts.  This behavior eludes the up to now simple categories used to classify toxic materials.  Since unlike their larger relatives, they can easily cross the skin, lung and in some cases the blood and brain barriers, they present a far more complex problem that needs to be studied.  Some of these nanoparticles produce further biochemical reactions which can lead to the creation of free radicals that damage cells.

via: Nature Materials
click to enlarge
The fact is that we are still not aware of the long term effects of nanoparticles in biological systems.  According to an article published in the July 2009 issue of  Nature Materials, titled, Understanding biophysciochemical interactions at the nano-bio interface, Nei et al., speak of the emergence of a "nano-bio interface,"
At the interface between nanomaterials and biological systems, the organic and synthetic worlds merge into a new science concerned with the safe use of nanotechnology and nano­ material design for biological applications. The ‘nano–bio’ inter­ face comprises the dynamic physicochemical interactions, kinetics and thermodynamic exchanges between nanomaterial surfaces and the surfaces of biological components (for example proteins, membranes, phospholipids, endocytic vesicles, organelles, DNA and biological fluids).
This is becoming a whole new world of reactions at the nano levels that where previously unknown, and do doubt, will become a whole new branch of science. This review cited in Nature Materials, highlighted four important research advancements as summarized by  eScience News.
  1. A classification of the interactions when nanomaterials contact and bind to biological systems.
  2. An understanding of how protein layers change the properties of the nanomaterials and the way in which they interact in the body.
  3. An understanding of how physicochemical properties such as size, charge, shape and other characteristics affect the ability of nanomaterials to enter a cell.
  4. An understanding of how nanoparticles elicit a wide range of intracellular responses, which depends on their properties, concentrations and interactions with biological molecules.
All of this shows just how much nanotechnology promises.  It shows how close we are in some areas to it reaching daily life.  This information also demonstrates the long road ahead in research, safety to us and our environment.  All of this information does not deter us from the belief that nanotechnology must come, that it will come and that we may not be ready for it.

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