Nanotechnology and our health– what nanotechnology can do for you.
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than 100 nanometres (nm). A nanometre is a millionth of a millimetre or a billionth of a meter. For those of us old enough to remember ancient high school science, the smallest measurement was supposedly the Angstrom. One Angstrom is ten nanometres. One hundred Angstrom or 1000nm is one micrometer, but don't worry about this because the term Angstrom has become generally redundant. We now measure tiny to a far greater degree of precision.
Nanotechnology involves a wide variety of disciplines; from physics to material science to biological, mechanical and chemical engineering. Its applications include medicine, robotics, self replicating machines, cosmetics, space exploration and modern warfare - where much research is predictably concentrated. Those engaged in nanotech are engaged in changing the world in from the bottom up. It is as the ETC Group says, 'the little big down.'
Getting a handle on the scale.
To get an idea of how small we are talking, here are some examples for context. A strand of DNA is 2.5nm wide, a protein molecule is 5nm, a red blood cell 7,000nm and a human hair is around 80,000nm wide. National Geographic encapsulated it nicely by saying a nanometre compared to a meter is the size of a marble as compared to the earth, or the distance your beard grows while you are lifting your razor to your face.
The dimensions are so tiny that special electron microscopes are needed to even engage in nanotechnology. Because photons are larger than electrons, this renders traditional light microscopy relatively useless at this scale. This is why the technology only really took off in the last quarter of a century or so.
So what is the big deal with small?
What happens when materials such as zinc or iron are refined to the nanoscale? The first thing is that they become far more reactive due to increased surface area. Another notable effect is that materials behave differently at nanoscale because of quantum effects in how materials operate at this scale – they may change colour, reactivity, elasticity, conductivity or strength. These effects do not generally occur at the sub micron scale - between 100 and 1000 nm - but only begin to exhibit below the 100 nm level.
Some agencies such as the US Food and Drug Administration (FDA) consider that all particles below 1000nm (one micron) which do exhibit unique properties should be classified as nanomaterials.
Obviously these altered properties offer huge possibilities to change the way we manage materials. For instance the winners of the 2007 Physics Nobel prize, Peter Grunberg and Albert Fert, described how particles have greater magnetoresistance and spin at nanoscale. This has already led to greatly improved information storage devices like hard drives. Ipod nano anyone?
We may be able to make entirely new medicines, composite materials like self cleaning windows, super strong materials, synthetic nano motors and much more using this evolving technology.
What has this got to do with health?
Because of the increased reactivity and quantum changes in how materials behave , concerns have been raised about the consequences of nanotechnology for human health.
The first concern is that nanotech is poorly regulated. In fact there are no legislative protocols to manage either the products of nanotech or the effects that pollution by nanoparticles may have on us or our environment. Indeed there is a major problem because nanomaterials are deemed to be substantially equivalent to the generally understood properties of the materials in larger scale, although this is broadly recognised amongst the scientific community as not being the case. So a material such as nano scale titanium or zinc is considered to have similar properties to traditional formulations.
This is where the first problems begin to present. The total lack of regulation of these materials undermines any transparency over their safety or even to provide meaningful guidelines on safety testing regimes. The only oversight comes from the developers who provide information to regulators such as the FDA and the US Environmental Protection Agency who are starting to ask for corporate self regulation.
Nevertheless regulators continue to follow the line of least resistance of not finding any negative effects by not looking, pretty much the same as has occurred with genetically modified foods. This is far from ideal but is triggered by concerns about interfering with innovation. We must however never forget that no proof of risk does not equate to no potential for harm; especially if nobody is looking. And how do you look for substances that are invisible at the best of times?
A group of specialist scientists raised concerns in the journal Nature about this lack of oversight. One of the authors, Anthony Seaton said, "there is international agreement among scientists that something needs to be done, but no government yet has really agreed put money into it. But in the meantime, many products are coming to market, and that's the slightly alarming thing."
In 2006 a nanotech bathroom cleaning product was withdrawn in Germany after widespread reactions by people using it. No information exists on its composition, emphasising the inherent lack of regulation.
Some local authorities such as the City of Berkeley in California, have instituted regulations, demanding that nanomaterials are identified in order that potentially hazardous materials can be tracked. Again these measures are inadequate. Especially now that nanomaterials are finding their way into our bodies.
Given that these materials are so tiny, the amounts generated in experiments are too small to supply sufficient material for testing. And if tests are run, what protocols are followed? These questions need to be addressed, a fact constantly emphasised by specialists operating in this field of endeavour.
So what products are effected?
Sunscreen.
The most widely used everyday use of nanotech at present is in the formulation of sunscreens. Nanoscale zinc oxide and titanium dioxide are being utilised in formulations to render them transparent. Given the size and the reactivity of the materials there is a potential for them to cross skin and even cell barriers. Tests have shown that nano titanium dioxide can cause organ pathologies, disturbances and respiratory distress in fish and can kill algae and water fleas. Its effects are exacerbated by UV light exposure. Likewise zinc and zinc oxide can have similar effects on these organisms. Other studies using mammals have shown organ damage, cell interference, genetic damage and generation of free radicals by zinc and titanium based nanoparticles.
A survey by Friends of the Earth of sunblocks in the USA and Australia has shown that many contain or potentially contain nanoparticles. Some manufacturers remain coy about disclosing this information while others claim it as beneficial. The fact is that the jury remains out. Some studies have shown problems, others have indicated low risk, largely dependent on who funded them. Whatever the case precaution seems to be advisable.
Notably, studies have shown little or no improvement in the UV screening ability of nanomaterial based sunscreens. Moreover, exposing these materials to UV light may increase the damage they inflict on cells.
In order to prevent risks try to use sunscreens that specifically state they do not use nanoparticles or use swimming costumes that are UV resistant or remain covered up as much as possible. A rule of thumb is that the more transparent a sunblock is when applied the greater the chance that it contains nanomaterials.
Other creams and cosmetics are also moving toward the use of nanomaterials.
Food.
A recent report by Friends Of the Earth on nanotechnology in food has shown an increasing use of nanomaterials in our food, packaging and processing. Nanoscale iron is added to nutritive drinks. Titanium, silver and zinc, silica and other molecules are used in packaging materials. Soil additives, pesticides and fertilisers are increasingly using nanotech to enhance their effectiveness due to increased bio-availability and reactivity.
Nestle and Unilever are reportedly working on a nano-ice cream with 'improved' properties. Nanomaterial linings are under development for foods like tomato sauce to help them to pour more easily, as well as antibacterial coverings and packaging, like nano-sliver coated chopping boards. Fruits and meats may be encapsulated in invisible nano films as thin as 5nm to maintain freshness and prevent spoilage.
Other substances such as fillers like food whiteners and anti-caking agents are already in use. Several materials processed by modern food technology may in fact inadvertently produce nanoscale material, through dry ball and ultrasound milling, amongst other methods.
Flavourants, vitamins, nutrients and other food enhancers are other areas receiving attention using this technology.
The effects of these remain unknown. Together with health effects, there are environmental risks arising out of the disposal of nanopackaging, containing materials such as silver, zinc and titanium. The leaching of nanoparticles into the water table is one such vector, especially as some nanomaterials have been noted to increase their reactivity in conjunction with other chemicals such as the sodium chloride in salt water. Their effects on aquatic life have already been noted above.
Other substances.
No doubt nanotechnology will evolve unforeseen new products with the passage of time. It is predicted to grow in value to in excess of three billion US Dollars by 2010 (from US$ 413 million in 2005), spinning off 1.5 trillion dollars of value . Within the next decade some project its value to increase to over three trillion US dollars! There are obviously massive vested interests at play here, mostly within established corporate structures.
The ability to use carbon in constructions such as buckyballs and nanotubes in engineering and space applications has already raised some red flags as nanotubes are potentially as hazardous as asbestos and are so small that they may interfere with cellular, mitochondrial and even genetic function.
Nano-silver is used in socks, towels and other personal items to keep odours and bacteria at bay. It is also used in air conditioning systems to remove bacteria and in washing machines for the same reason. This may be benign but it could also disrupt microbial cycles and have downstream environmental effects.
Grey and green goo.
Eric Drexler, who wrote about nanotechnology in its early years, postulated the potential of 'grey goo' to wreak havoc. In this hypothesis – and it remains no more than an hypothesis – a self replicating nanomaterial is invented that is unable to be controlled. Given its potential to self replicate it would have the ability to spread unchecked, rapidly taking over the earth. This is unlikely but not impossible.
What is more worrying is the potential of 'green goo,' a biosynthetic form generated through the marriage of nanotechnology with genetic engineering that could become self replicating through natural means but with similar results. Something similar may have occurred if an early experiment to enhance various soil bacteria through genetic engineering had not been halted because of its potential to destroy soil bacteria instead of enhance them .
The need to regulate.
The United Kingdom's Royal Society together with the Royal Academy of Engineering have called for the environmental release of nanoparticles to be "avoided as far as possible", and for their intentional release to "be prohibited until appropriate research has been undertaken and it can be demonstrated that the potential benefits outweigh the potential risks."
These recommendations appear to be sensible minimum requirements to apply when using these novel materials. Similar concerns have been stated by numerous other groups, both from within the Scientific fraternity and from NGOs such as The ETC group and Friends of the Earth.
South Africa is engaging on nanotech research with alacrity. We need to place local regulation and oversight mechanisms in place in order to minimise the risks and downsides while not impeding potentially beneficial discoveries. We would be irresponsible if we fail to do institute such oversight. Technology is not neutral – it is the instrument of its own evolution and the ways that human society organises itself has direct implications in how technologies are evolved and handled.
Beside dealing with this technology we equally need to pay attention to the alternatives should we wish to avoid either the fruits or pitfalls of technology, as is our democratic right.
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This article draws from the recently published 'Out of the Laboratory and on to our plates – Nanotechnology in Food and Agriculture,' compiled, published and circulated by Friends of the Earth Australia, USA and Europe. 2008. Further reading and references are also included.
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Start Box
What are the alternatives.
Michael Pollan, in his new book "In Defence of Food: An Eaters Manifesto" sensibly suggests that we should only eat food that our grandmothers would recognise. Beside avoiding highly processed food, crammed with additives, natural foods offer the best alternative to unwitting exposure by nanoparticles or other risky chemicals. Organic food, produced without pesticides, noxious chemicals or fertilisers offers a good alternative. Growing our own food is a great alternative to an increasing reliance on processed foods.
The same applies to our cosmetics, clothes, food utensils and packaging – we need to remain vigilant while not becoming paranoid.
There are arguments by some that we cannot and will not be able to regulate this technology and that some sort of moratorium should be placed on its employment before it is commercialised.
It seems sensible to assert a discretionary, precaution based stance in the case of nanotechnology.
End box
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Further reading
Engines of Creation: The Coming Era of Nanotechnology.
Eric Drexler.
Anchor Books, New York, 1986, Oxford University Press, Oxford, 1990, Fourth Estate, London, 1996
Free download with additional notes at
http://www.wowio.com/users/product.asp?BookId=503
The Little Big Down: A Small Introduction to Nano-scale Technologies
By the ETC Group. 2004.
http://www.etcgroup.org/en/materials/publications.html?pub_id=104
A Tiny Primer on Nano-scale Technologies ...and The Little BANG Theory
By the ETC Group. 2005.
http://www.etcgroup.org/en/materials/publications.html?pub_id=55
Nanotech News in Living Colour: An Update on White Papers, Red Flags, Green Goo (and Red Herrings)
By the ETC Group. 2006
http://www.etcgroup.org/en/materials/publications.html?pub_id=95
Nanotechnology and Sunscreens – A consumer guide for avoiding nano-sunscreens.
By Friends of the Earth Australia and USA. 2007.
http://www.foe.org/nano_sunscreens_guide/Nano_Sunscreens.pdf
Out of the Laboratory and on to our plates – Nanotechnology in Food and Agriculture.
By Friends of the Earth Australia, USA and Europe. 2008.
http://www.foeeurope.org/activities/nanotechnology/index.htm
i) Out of the Laboratory and on to our plates, Nanotechnology in Food & Agriculture. Friends of the Earth (FOE) Europe, Australia and USA. March 2008. Pg, 4.
ii) Nanotech Small science generates big questions.
Canadian Broadcasting Corporation http://www.cbc.ca/news/background/science/nanotechnology.html
iii) Toxic Potential of Materials at the Nanolevel. A. Nel (not the cricketer!), et al. Science. February 2006, Vol. 311. no. 5761, pp. 622 ? 627. http://www.sciencemag.org/cgi/content/abstract/311/5761/622
iv) Out of the Laboratory and on to our plates, Nanotechnology in Food & Agriculture. Friends of the Earth (FOE) Europe, Australia and USA. March 2008 pp 5, 22-28
v) Investing in nanotechnology stocks - golden opportunity or bad idea? January 2005. http://www.nanowerk.com/spotlight/spotid=1328.php
Hazards of Genetically Engineered Food. Prof. R. Cummins. 2000. http://articles.mercola.com/sites/articles/archive/2000/12/03/ge-food-part-one.aspx
vi) U.K. Royal Society, Royal Academy of Engineering 2004, Section 5.7: paragraph 63 ? from the FOE report ibid.
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