Wednesday 17 July 2013

Nanosilver: the future may be tiny and shiny, but is it safe?

A few years' ago I bought some socks containing nanosilver in the hope of reducing foot odour - or more specifically a lingering smell in shoes - I am not proud. Strangely, moving to a warmer, more humid climate since then has greatly reduced the problem, rather more so than the nanosilver, which was frankly useless. But soon after buying the less-than-super socks I started thinking about just what I had done. After all, you don't usually consider yourself in close proximity to amounts of silver around one billionth or so of a metre in size...

In the case of nanosilver, it has long been recognised as an anti-bacterial agent and fungicide too, hence the sock idea. I've already discussed smart materials elsewhere but felt this particular example deserved a post by itself. So just how efficient was the nanosilver anyway? According to studies in 2008 and 2009, up to one third of the metal is washed out at the first laundering. Hardly a long-term solution then! So what happens to the silver that disappears down the washing machine waste pipe? Could the nanoparticles get into the water supply if not removed in treatment plants, evading capture due to the minuteness of their size? I just had to find out!

It seems that silver-impregnated socks are just the tip of the iceberg, with all sorts of products in recent years taking advantage of its anti-bacterial capability. Everything from washing machines to vacuum cleaners has appeared, some removed from the market, if only a temporary basis, due to growing health concerns. But is the use of nanosilver just a fad, with little scientific evidence to support its alleged efficacy? In 2006 the New Zealand manufacturer Fisher and Paykel announced that there was no point incorporating nanosilver into their washing machines since a 20 degrees Celsius wash cycle using detergent would remove over 99 per cent of bacteria anyway! The same, year, the US Environmental Protection Agency claimed that it would introduce some nanotechnology-related legislation, although there seems to have been limited action in the meantime, to say the least.

Meanwhile other nations carry on regardless and allow if anything a greater than ever range of products with little attempt to investigate either their efficacy or ecological impact. Although found in some genuine anti-bacterial medical products, colloidal silver (that is, 1-1000 nanometre-sized silver particles in solution) is now being aggressively marketed after several decades in the doldrums. Claims for its use range from the mildly optimistic (in, for example, toothbrushes) to obvious quackery (a cure for AIDs, would you believe?) Clearly the manufacturers of alternative medicines have found a new weapon for their arsenals. But since gold is the only inert metal when it comes to ingestion - think gold flakes in vodka - just how safe is silver in any form of consumed product?

Starting with the assumption that there are no known cases of death by 'medicinal' products containing silver it might appear that consumers are just wasting their money, but there are plenty of other issues if you consider the bigger picture. Which in this case is the planetary ecosystem. Firstly, any overuse of household antibacterial agents can reduce children's immunity, although silver-based products are probably small fry compared to the myriad of cleaning sprays, gels and wipes aimed to keeping the family home 'safe from germs'. And since silver cannot differentiate between useful/symbiotic and harmful/disease-causing bacteria, the application is more akin to machine gun fire - with its consequences of 'collateral damage' - than a precision-targeted solution.

Next, the natural variation in the bacterial gene pool can lead to the sort of problems that hospitals are now facing with the likes of the MRSA 'superbug', namely that killing 99.9% of bacteria leaves the remaining 0.1% to form the one hundred per cent of the next, completely immune generation. A perfect example of inadvertent natural selection. Or should that be unintended artificial selection? However you define it, we are now starting to pay the price for thoughtless use (and frequent overuse) of our war against microbes.

Finally, back to my original question as to what happens to the ever-increasing amount of nanosilver washed down the drains from the likes of our socks (and the washing machines themselves). According to recent Swiss research, circa 95% of waste water nanosilver ends up as silver sulphide and is therefore relatively harmless. So need I have worried about where the material was ending up? Well, 5% on a global scale could still be considered a substantial amount, and since sewage sludge can end up being dumped on farm land - 3 to 4 million tonnes per year in the UK alone - could there be residual consequences on the soil bacteria, fungi, earthworms and of course farm produce destined for human consumption? Even a subtle shift in the microbial population could have a profound effect on the ecosystem and therefore the human food chain, if you want to be purely selfish about it.

This latter may sound like unsubstantiated scaremongering, but considering the history of research, often industry-sponsored, that has downplayed or even denied the dangers of nicotine, leaded petrol, DDT and various others, might it be too soon to say that the risk is non-existent? The lack of scientific evidence, combined with the poor efficacy of products such as my impregnated socks, suggest that fashionable capitalism is the primary reason behind much of the use of nanosilver. As we all know, mindlessly following others can lead to all sorts of problems. If there's a lesson here, it’s think before you shop: if you want to buy something small, shiny and made of silver, there are plenty of tried and trusted alternatives!

Tuesday 18 June 2013

Deserving dollars: should mega budget science be funded in an age of austerity?

With the UK narrowly avoiding France's fate of a triple dip recession, I thought I would bite the bullet and examine some of the economics of current science. In a time when numerous nations are feeling severe effects due to the downturn, it is ironic that there are a multitude of science projects with budgets larger than the GDP of some smaller nations. So who funds these ventures and are they value for money, or even worthwhile, in these straitened times? Here are a few examples of current and upcoming projects, with the lesser known the project the more the information supplied:

National Ignition Facility

The world's most powerful laser was designed with a single goal: to generate net energy from nuclear fusion by creating temperatures and pressures similar to those in the cores of stars. However, to state that the NIF has not lived up to expectation would be something of an understatement. According to even the most conservative sources, the original budget of the Lawrence Livermore National Laboratory project has at the very least doubled if not quadrupled to over US$4 billion, whilst the scheduled operational date came five years overdue.

I first learned of the project some years ago thanks to a friend who knew one of the scientists involved. The vital statistics are astonishing, both for the scale of the facility and the energies involved. But it seems that there may be underlying problems with the technology. Over-reliance on computer simulations and denial of deleterious experimental results on precursor projects, as well as the vested interests of project staffers and the over-confident potential for military advances, have all been suggested as causes for what history may conclude as a white elephant. So perhaps if you are looking for an archetypal example of how non-scientific factors have crippled research, this may well be it.

Unlike all the other projects discussed, the National Ignition Facility is solely funded by one nation, the USA. Of course, it could be argued that four billion dollars is a bargain if the project succeeded, and that it is today's time-precious society that needs to learn patience in order to appreciate the long-term timescales required to overcome the immense technological challenges. Nuclear fusion would presumably solve many of todays - and the foreseeable futures - energy requirements whilst being rather more environmentally friendly than either fossil fuels or fission reactors. The potential rewards are plain for all to see.

However, the problems are deep-rooted, leading to arguments against the development of laser-based fusion per se. Alternative fusion projects such as the Joint European Torus and the $20 billion ITER - see an earlier post on nuclear fusion research for details - use longer-established methods. My verdict in a nutshell: the science was possibly unsound from the start and the money would be better spent elsewhere. Meanwhile, perhaps the facility could get back a small portion of its funding if Star Trek movies continue to hire the NIF as a filming location!

The International Space Station

I remember the late Carl Sagan arguing that the only benefit of the ISS that couldn’t be achieved via cheaper projects such as – during the Space Shuttle era - the European Space Agency’s Spacelab, was research into the deleterious effects on health of long-duration spaceflight. So at $2 billion per year to run is it worthwhile, or but another example of a fundamentally flawed project? After all, as it is the station includes such non-scientific facets as the ultimate tourist destination for multi-millionaires!

Sometimes referred to as a lifeline for American and Russian aerospace industries (or even a way to prevent disaffected scientists in the latter from working for rogue states), I have been unable to offer a persuasive argument as to why the money would not have been better spent elsewhere. It is true that there has been investigation into vaccines for salmonella and MRSA, but after twelve years of permanent crewing on board the station, just how value for money has this research been? After all, similar studies were carried out on Space Shuttle flights in previous few decades, suggesting that the ISS was not vital to these programmes. The Astronomer Royal Lord Martin Rees has described as it as a 'turkey in the sky', siphoning funds that could have been spent on a plethora of unmanned missions such as interplanetary probes. But as we should be aware, it usually isn't a case that money not spent on one project would automatically become available for projects elsewhere.

On a positive scientific note, the station has played host to the $2 billion Alpha Magnetic Spectrometer - a key contender in the search for dark matter - which would presumably have difficulty finding a long-duration orbital platform elsewhere. But then this is hardly likely to excite those who want immediate, practical benefits from such huge expenditure.

The ISS has no doubt performed well as a test bed for examining the deterioration of the human body due to living in space, if anything seriously weakening the argument for a manned Mars mission in the near future. Perhaps one other area in which the station has excelled has been that of a focal point for promoting science to the public, but surely those who follow in Sagan’s footsteps - the U.K.'s Brian Cox for one - can front television series with a similar goal for the tiniest fraction of the cost?

The Large Hadron Collider

An amazing public-relations success story, considering how far removed the science and technology are from everyday mundanity, the world's largest particle accelerator requires $1 billion per year to operate on top of a construction budget of over $6 billion. With a staff of over 10,000 the facility is currently in the midst of a two-year upgrade, giving plenty of time for its international research community to analyse the results. After all, the Higgs Boson A.K.A. 'God particle' has been found…probably.

So if the results are confirmed, what next? Apparently, the facility can be re-engineered for a wide variety of purposes, varying from immediately pragmatic biomedical research on cancer and radiation exposure to the long-term search for dark matter. This combination of practical benefits with extended fundamental science appears to be as good a compromise as any compared to similar-scale projects. Whether similar research could be carried out by more specialised projects is unknown. Does anyone know?

As for the future of mega-budget schemes, there are various projects in development extending into the next decade. The Southern Hemisphere is playing host to two large international collaborations: the Square Kilometre Array is due to begin construction in eleven nations - excluding its UK headquarters - in 2016, but it will be around eight years before this $2 billion radio telescope array is fully operational. Meanwhile the equally unimaginatively-named European Extremely Large Telescope is planned for a site in Chile, with an even longer construction period and a price tag approaching $1.5 billion. Both projects are being designed for a variety of purposes, from dark matter investigation to searching for small (i.e. Earth-sized) extra-solar planets with biologically-modified atmospheres.

At this point it is pertinent to ask do extremely ambitious science projects have to come with equally impressive price tags? Personally I believe that with a bit more ingenuity a lot of useful research can be undertaken on far smaller budgets. Public participation in distributed computing projects such as Folding@home and Seti@home, in which raw data is processed by home computers, is about as modest an approach as feasible for such large amounts of information.

An example of a long-term project on a comparatively small budget is the US-based Earthscope programme, which collects and analyses data including eminently practical research into seismic detection. With a construction cost of about $200 million and annual budget around a mere $125 million this seems to be a relative bargain for a project that combines wide-scale, theoretical targets with short-term, pragmatic gains. But talking of practical goals, there are other scientific disciplines crying out for a large increase in funding. Will the explosive demise of a meteor above the Russian city of Chelyabinsk back in February act as a wake-up call for more research into locating and deflecting Earth-crossing asteroids and comets? After all, the 2014 NASA budget for asteroid detection projects is barely over the hundred million dollar mark!

I will admit to some unique advantages to enormous projects, such as the bringing together of researchers from the funding nations that may lead to fruitful collaboration. This is presumably due to the sheer number of scientists gathered together for long periods, as opposed to spending just a few days at an international conference or seminar, for instance. Even so, I cannot help but feel that the money for many of the largest scale projects could be bettered used elsewhere, solving some of the immediate problems facing our species and ecosystem.

Unfortunately, the countries involved offer their populations little in the way of voice as to how public money is spent on research. But then considering the appalling state of science education in so many nations, as well as the short shrift that popular culture usually gives to the discipline, perhaps it isn’t so surprising after all. If we want to make mega-budget projects more accountable, we will need to make fundamental changes to the status of science in society. Without increased understanding of the research involved, governments are unlikely to grant us choice.