Definitions

In general I am not sympathetic to spending a lot of time on definitions of nano; whilst all of these distinctions have some intellectual validity they are not much help to you; and in any case they reflect various political positions more than actual science/technology. The ‘definition’ below is perhaps more general and may help!

I much prefer (as the ministerial panel I was a member of did) to focus on nano as the convergence of ‘top-down’ (eg lithographic) technology and ‘bottom-up’ (eg molecular) technology. This is more-or-less 10-100nm; but size as such is incidental –this may help you as it focuses on what is actually different (and potentially hazardous) about nano. For example, in the light of this whilst in planning a national programme I would be inclusive, from your perspective those whose selling point is ‘nano-accuracy’ on micro/macro objects are largely irrelevant.

I also have not much sympathy with the effort to distinguish ‘science’ from ‘technology’; the (political) idea seems to be that the public might accept a few ‘science’ experiments rather than an actual ‘technology’ deployment. Firstly I doubt this – even today there are C nanotube companies supporting the science; and look at GM crops! Secondly I think that the best approach is to convince the public that nano has real benefits as well as potential hazards; saying (correctly) that nanoparticulate and nanostructured materials are already out there showing real benefits without apparent hazards helps this case. A similar (no doubt accidental) approach has worked with mobile phones whereas the wholly ‘new’ GM with less obvious benefits has had much more serious problems.


Current State of Knowledge

This is fine so far as it goes; but it does not go far! Many items are missing (QW lasers/electronic devices already used in CDs/satellite receivers for example); and particulate/molecular is thin. Again the Taylor report is more complete. Metrological issues are fine (I sit on the National Measurement System ‘Quantum’ group that is supporting this) but seems marginal for you.

 

Applications

Seems to mention every geopolitical trend bit not much nano! Taylor report (and others) are more complete.

Seems sensible so far as it goes; but it may be too negative. It is very easy to show the impossibility of the Micheal Crighton ‘flying nanobots’ scenario on energy/fluid dynamics alone (the machines will not do better than swarming insects and will initially be much worse) and this could be worth doing; preferably before the movie comes out (anyone know when this is?). Sci-Fi is not necessarily bad; Neal Stephenson’s ‘The Diamond Age’, also about nano (and set in future Shaghai) is much more fun!

‘Other Areas’

Airborne nanoparticles seems to be the main issue for health; and it is very important to distinguish these from the much larger nanostructured device/materials topic.

It is also important to avoid the journalistic ‘it’s all pretty small stuff’ scenario (this is real – I have spoken to science journalists who see it this way). To be obvious but specific, equally size-spaced objects might be:-

• Nanoparticles – say 10nm
• Microparticles – say 10 µm (cf PM10)
• Marbles – say 10mm!

So yes, small is different, and nano is different, but nano is as different from micro (with its known inhalation hazards) as micro is from marbles!

In particular it is not justified to assume that the (even now not well-understood) cancer hazards of micro airborne particles will carry over to nano (indeed there are many obvious reasons why not) – a case for care maybe but not a case for assuming the worst. Although you do not mention the ‘precautionary principle’ – a phrase beloved of doomsters but as meaningless as the ‘Law of Averages’, someone will!


Nanomaterials

Yes – milk as nano rather appeals, but I think that any nano-colloid would be clear to look at for obvious physical reasons so it may be a more limited set!

(b) – in fact 2-D wires are common in electronic devices.

Sunscreens – if this causes no problems it seems to be a catch-all since usage is intimate and widespread; and presumably vice-versa. What trials have been done?

Otherwise fine.

(d) For ‘Quantum lasers’ substitute ‘Quantum dot lasers’ as this is what was intended; but note that in fact these are in modest production and Quantum Well (1D) lasers are in very large scale production.

Hazards

One needs to be selective here in relation to likely public concerns, for example pyrophoricity is an issue for flour and wood mills but is very unlikely to be an issue for nanofab on any short timescale; and who avoids bread for this reason anyway!?

I also am concerned that even having workshops on this without due cause serves to promote unfounded worries. Things said need development; for example there are vast numbers of nanoparticles already in the environment, how much has been done to check this and do basic statistics on the result? For example research on (100’s of people on) mobile phone hazards is completely overtaken by the 100’s M people already using them. Much the same could apply to skin absorption and sunscreens.

Electronics/Photonics

Seems to be missing quantum dot/well/wire stuff, semiconductor nanowires and photonic crystals.

Applications (current & short-term) a bit modest; where are all the CD lasers, displays, satellite receiver electronics, microwave….

Longer-term the microlasers seem missing, and RFID technology, biosensors...

And self-assembled electronics, whilst high-risk, is a good research item.

Fictions list seems a bit conservative and maybe needs to say that single-photon and single-electron devices are very real.

As at the FST meeting last week I do not see any distinctive ethical issues.

Bio-nano

The strongest section; maybe underestimates the bio-medical-nano-sensing and instrumentation applications; all the way to DNA live profiling (long term!).

Environment

Surely flames generate significant numbers of nanotubes in the soot?

I believe that nanoparticles tend to coalesce in air and may consequently be short-lived. Research in support of this might be helpful.

‘Similarly, the publics’ perception that nanotechnology is different from other technologies is incorrect. Nanotechnology has however prompted the collaboration of scientists from differing fields of existing technology on a scale that probably has not been seen before.’

This seems very sensible!

Will Stewart FREng