Blood-related diseases

Many diseases, from heart attacks and strokes to sepsis and metastasizing cancer, involve the blood in some way. The author has proposed an aggressive nanomedical device, a "Vasculoid" , that would replace the blood volume and take over its functions by lining the entire vascular system with a multi-segmented robot. In addition to preventing many diseases, and limiting the scope of others (such as poisoning), such a system would provide detailed control of the body's chemical environment around each individual capillary, allowing heterostasis to be used extensively.

The Vasculoid is extremely complicated and would require much research to build and use successfully. This particular device may never be used, but it can provide a hint of the possibilities inherent in advanced nanomedicine.

Ethical Issues

Genetic Modification

It is likely that some conditions will be treated most easily by modifying the body's genetic material. Many people are disturbed by this idea, especially if the modification is transmissible to offspring. However, once we have a nanotechnology that can directly manipulate the genes, transmission of modified genes need not be a cause for concern. Any genetic manipulation that turns out to be a bad idea will be reversible. Furthermore, it would be trivial to edit the DNA of any offspring while still in embryo stage in order to remove the modifications. The idea that a genetic modification will irreversibly change the whole species becomes incorrect once genes can easily be directly manipulated.

Overpopulation

A common objection to life extension is that if everyone lives forever, the earth will become overcrowded. However, a little math will demonstrate that the earth can become overcrowded much faster due to excess births than due to reduced death. If everyone killed themselves after 80 years of life, that act would remove only one person from the population; meanwhile their children and grandchildren would be reproducing. But a person who chose to live a long time and have one fewer child would be reducing the population by more than one, since a nonexistent person can't have children. (Robert J. Bradbury points out that nanotechnology will also give us cheaper access to space. Using a fairly basic design (see references), it would be feasible for earth's entire population to leave the earth and live in space.)

Poor Health

Today, people are kept alive for years in terrible health, sometimes beyond the point where they wish to die. This has given life extension a bad reputation. Merely extending life without improving health is often a bad idea. The good news is that if health is improved, life will naturally be extended. Once we have the technology to eliminate diseases, we need no longer worry about living on in bad health.

Elitism

It has been argued that it would be selfish for some people to extend their lives when the technology is not available to everyone. However, life extension will not be a single technology hoarded by an elite--instead, it will be a natural consequence of health maintenance. Inequities in availability of health care are widespread today, and curing more diseases will not make the problem worse. On the other hand, development of more effective medical tools will reduce the cost of medical care. If you want to increase the availability and reduce the cost of a technology, you should invest in research and development, and buy more technology. The more people who make use of health maintenance technologies, the faster they will become cheap and widely available. (Several large private foundations are working to make medical care widely available in the developing world.)

Nanocosmetics in the news

Uncertainties surrounding the use of nanoparticles in cosmetics made the news in the UK this followed a press release from the consumer group Which? – Beauty must face up to nano. This is related to a forthcoming report in their magazine, in which a variety of cosmetic companies were asked about their use of nanotechnologies.

The two issues that concern Which? are some continuing uncertainties about nanoparticle safety and the fact that it hasn’t generally been made clear to consumers that nanoparticles are being used. Their head of policy, Sue Davies, emphasizes that their position isn’t blanket opposition: “We’re not saying the use of nanotechnology in cosmetics is a bad thing, far from it. Many of its applications could lead to exciting and revolutionary developments in a wide range of products, but until all the necessary safety tests are carried out, the simple fact is we just don’t know enough.” Of 67 companies approached for information about their use of nanotechnologies, only 8 replied with useful information, prompting Sue to comment: “It was concerning that so few companies came forward to be involved in our report and we are grateful for those that were responsible enough to do so. The cosmetics industry needs to stop burying its head in the sand and come clean about how it is using nanotechnology.”

On the other hand, the companies that did supply information include many of the biggest names - L’Oreal, Unilever, Nivea, Avon, Boots, Body Shop, Korres and Green People - all of whom use nanoparticulate titanium dioxide (and, in some cases, nanoparticulate zinc oxide). This makes clear just how widespread the use of these materials is (and goes someway to explaining where the estimated 130 tonnes of nanoscale titanium dioxide being consumed annually in the UK is going).

The story is surprisingly widely covered by the media. Many focus on the angle of lack of consumer information, including the BBC, which reports that “consumers cannot tell which products use nanomaterials as many fail to mention it”, and the Guardin, which highlights the poor response rate. The story is also covered in the Daily Telegraph, while the Daily Mail, predictably, takes a less nuanced view. The Mail explains that “the size of the particles may allow them to permeate protective barriers in the body, such as those surrounding the brain or a developing baby in the womb.”

It may well be that these ingredients are present in such small quantities that there is no possibility of danger, but given the uncertainties surrounding fullerene toxicology putting products like this on the market doesn’t seem very smart, and is likely to cause reputational damage to the whole industry. There is a lot more data about nanoscale titanium dioxide, and the evidence that these particular nanoparticles aren’t able to penetrate healthy skin looks reasonably convincing. They deliver an unquestionable consumer benefit, in terms of screening out harmful UV rays, and the alternatives - organic small molecule sunscreens - are far from being above suspicion. But, as pointed out by the EU’s Scientific Committee on Consumer Products, there does remain uncertainty about the effect of titanium dioxide nanoparticles on damaged and sun-burned skin. Another issue recently highlighted by Andrew Maynard is the issue of the degree to which the action of light on TiO2 nanoparticles causes reactive and potentially damaging free radicals to be generated. This photocatalytic activity can be suppressed by the choice of crystalline structure (the rutile form of titanium dioxide should be used, rather than anatase), the introduction of dopants, and coating the surface of the nanoparticles. The research cited by Maynard makes it clear that not all sunscreens use grades of titanium dioxide that do completely suppress photocatalytic activity.

This poses a problem. Consumers don’t at present have ready access to information as to whether nanoscale titanium dioxide is used at all, let alone whether the nanoparticles in question are in the rutile or anatase form. Here, surely, is a case where if the companies following best practise provided more information, they might avoid their reputation being damaged by less careful operators.

Responsible nanotechnology – from discourse to practice

There were some interesting facts looking at the empirical evidence for the development, or otherwise, of regional clusters with particular strengths in nanotechnology; under discussion was the issue of whether new industries based on nanotechnologies would inevitably be attracted to existing technological clusters like Silicon Valley and the Boston area, or whether the diverse nature of the technologies grouped under this banner would diffuse this clustering effect.

In the governance section, the University of Twente’s Arie Rip, one of the doyens of European science studies, spoke on the title “Discourse and practice of responsible nanotechnology development”. So many people had adopted the rhetoric of “responsible development” simply as a way of promoting the subject and deflecting criticism. However, Rip’s message was actually rather more optimistic than this. His view was that, however much such as rhetoric, it does translate into real practice, and the interactions we’re seeing between technology and society, in the form of public dialogue, discussions between companies and campaigning groups, and the development of codes of practice really are creating “soft structures” and “soft law” that are beginning to have a real, and beneficial, effect on the way these technologies are being introduced.

From mocro to nano medical applicalions

Nanotechnology in Medicine and Biotechnology, which raised the question of what is the right size for new interventions in medicine. There’s an argument that, since the basic operations of cell biology take place on the nano-scale, that’s fundamentally the right scale for intervening in biology. On the other hand, given that many current medical interventions are very macroscopic, operating on the micro-scale may already offer compelling advantages.

Jon Cooper gave some nice examples illustrating this. His title was Integrating nanosensors with lab-on-a-chip for biological sensing in health technologies, and he began with some true nanotechnology. This involved a combination of fluid handling systems for very small volumes with nanostructured surfaces, with the aim of detecting single biomolecules. This depends on a remarkable effect known as surface enhanced Raman scattering. Raman scattering is a type of spectroscopy that can detect chemical groups with what is normally rather low sensitivity. But if one illuminates metals with very sharp asperities, this hugely magnifies the light field very close to the surface, increasing sensitivity by a factor of ten million or so. Systems based on this effect, using silver nanoparticles coated so that pathogens like anthrax will stick to them, are already in commercial use. But Cooper’s group uses, not free nano-particles, but very precisely structured nanosurfaces. Using electron beam lithography his group creates silver split-ring resonators - horseshoe shapes about 160 nm across. With a very small gap one can get field enhancements of a factor of one hundred billion, and it’s this that brings single molecule detection into prospect.

On a larger scale, Cooper described systems to probe the response of single cells - his example involved using a single heart cell (a cardiomyocyte) to screen responses to potential heart drugs. This involved a pico-litre scale microchamber adjacent to an array of micron size thermocouples, which allow one to monitor the metabolism of the cell as it responds to a drug candidate. His final example was on the millimeter scale, though its sensors incorporated nanotechnology at some level. This was a wireless device incorporating an electrochemical blood sensor - the idea was that one would swallow this to screen for early signs of bowel cancer. Here’s an example where, obviously, smaller would be better, but how small does one need to go?

What’s meant by “Food nanotechnology”?

The latter group recently released a report on food nanotechnology –Out of the laboratory and on to our plates: Nanotechnology in food and agriculture;; according to the press release, this “reveals that despite concerns about the toxicity risks of nanomaterials, consumers are unknowingly ingesting them because regulators are struggling to keep pace with their rapidly expanding use.” The position of the CIAA is essentially that nanotechnology is an interesting technology currently in research rather than having yet made it into products. One can get a good idea of the research agenda of the European food industry from the European Technology Platform Food for Life.

What makes the subject of nanotechnology particularly confusing and contentious is the ambiguity of the definition of nanotechnology when applied to food systems. Most people’s definitions are something along the lines of “the purposeful creation of structures with length scales of 100 nm or less to achieve new effects by virtue of those length-scales”. But when one attempts to apply this definition in practise one runs into difficulties, particularly for food. It’s this ambiguity that lies behind the difference of opinion we’ve heard about already today about how widespread the use of nanotechnology in foods is already. On the one hand, Friends of the Earth says they know of 104 nanofood products on the market already (and some analysts suggest the number may be more than 600). On the other hand, the CIAA (the Confederation of Food and Drink Industries of the EU) maintains that, while active research in the area is going on, no actual nanofood products are yet on the market. In fact, both parties are, in their different ways, right; the problem is the ambiguity of definition.

The issue is that food is naturally nano-structured, so that too wide a definition ends up encompassing much of modern food science, and indeed, if you stretch it further, some aspects of traditional food processing. Consider the case of “nano-ice cream”: the FoE report states that “Nestlé and Unilever are reported to be developing a nano- emulsion based ice cream with a lower fat content that retains a fatty texture and flavour”. Without knowing the details of this research, what one can be sure of is that it will involve essentially conventional food processing technology in order to control fat globule structure and size on the nanoscale. If the processing technology is conventional (and the economics of the food industry dictates that it must be), what makes this nanotechnology, if anything does, is the fact that analytical tools are available to observe the nanoscale structural changes that lead to the desirable properties. What makes this nanotechnology, then, is simply knowledge. In the light of the new knowledge that new techniques give us, we could even argue that some traditional processes, which it now turns out involve manipulation of the structure on the nanoscale to achieve some desirable effects, would constitute nanotechnology if it was defined this widely. For example, traditional whey cheeses like ricotta are made by creating the conditions for the whey proteins to aggregate into protein nanoparticles. These subsequently aggregate to form the particulate gels that give the cheese its desirable texture.

It should be clear, then, that there isn’t a single thing one can call “nanotechnology” – there are many different technologies, producing many different kinds of nano-materials. These different types of nanomaterials have quite different risk profiles. Consider cadmium selenide quantum dots, titanium dioxide nanoparticles, sheets of exfoliated clay, fullerenes like C60, casein micelles, phospholipid nanosomes – the risks and uncertainties of each of these examples of nanomaterials are quite different and it’s likely to be very misleading to generalise from any one of these to a wider class of nanomaterials.

To begin to make sense of the different types of nanomaterial that might be present in food, there is one very useful distinction. This is between engineered nanoparticles and self-assembled nanostructures. Engineered nanoparticles are covalently bonded, and thus are persistent and generally rather robust, though they may have important surface properties such as catalysis, and they may be prone to aggregate. Examples of engineered nanoparticles include titanium dioxide nanoparticles and fullerenes.

In self-assembled nanostructures, though, molecules are held together by weak forces, such as hydrogen bonds and the hydrophobic interaction. The weakness of these forces renders them mutable and transient; examples include soap micelles, protein aggregates (for example the casein micelles formed in milk), liposomes and nanosomes and the microcapsules and nanocapsules made from biopolymers such as starch.

So what kind of food nanotechnology can we expect? Here are some potentially important areas:

• Food science at the nanoscale. This is about using a combination of fairly conventional food processing techniques supported by the use of nanoscale analytical techniques to achieve desirable properties. A major driver here will be the use of sophisticated food structuring to achieve palatable products with low fat contents.

• Encapsulating ingredients and additives. The encapsulation of flavours and aromas at the microscale to protect delicate molecules and enable their triggered or otherwise controlled release is already widespread, and it is possible that decreasing the lengthscale of these systems to the nanoscale might be advantageous in some cases. We are also likely to see a range of “nutriceutical” molecules come into more general use.

• Water dispersible preparations of fat-soluble ingredients. Many food ingredients are fat-soluble; as a way of incorporating these in food and drink without fat manufacturers have developed stable colloidal dispersions of these materials in water, with particle sizes in the range of hundreds of nanometers. For example, the substance lycopene, which is familiar as the molecule that makes tomatoes red and which is believed to offer substantial health benefits, is marketed in this form by the German company BASF.

What is important in this discussion is clarity – definitions are important. We’ve seen discrepancies between estimates of how widespread food nanotechnology is in the marketplace now, and these discrepancies lead to unnecessary misunderstanding and distrust.