Why doesn’t the tube make handpoles out of self-sterilising metals? And what is grippage?

Why don't these kill germs? The interior of an ageing Circle line train in 2010. Image: Maurits90/Wikimedia Commons.

In February 2015, bacteriologists from Cornell University published their results after spending more than a year swabbing New York City’s Subway trains and stations for bacteria. The results sounded icky: not only are there hundreds of different microbial species living throughout NYC’s transit system, on the poles and seats and turnstiles that humans touch every day, but half of them were completely unfamiliar to science. Anthrax and the bubonic plague were among those bacteria which were recognised.

Of course, the fact that New Yorkers aren’t dying off like 14th century Europeans implies that the dirtiness (or, rather, perceived dirtiness) of the subway isn’t a pressing public health issue. The study authors were keen to point out that commuters shouldn’t overreact to the news.

The same will apply to London, both in terms of the microbes living throughout the Underground and in the near-non-existent risk they pose to travellers. Yet as I was sat on one of Transport for London’s new S Stock trains on the Hammersmith & City line last week, fully aware of the first signs of a cold in my nose and my throat, my thoughts drifted to that study.

TfL likes to colour-code its lines so that the interior decor of the trains matches the lines they run on (so orange on the Overground, blue on the Piccadilly, etc.). These new trains are running on the Metropolitan (purple), District (green), Hammersmith & City (pink) and Circle (yellow) lines – yet all are decked out in bright, garish yellow. God knows what’s living on those neon poles and handstraps that keep passengers from falling down.

We know that public transport is a vector for disease transmission, especially when it comes to seasonally-influenced illnesses like the flu. We also know that there are materials which self-sterilise – that is, they’re highly toxic for any single-cell organisms that are unfortunate enough to land on them. This “oligodynamic effect” was first discovered in 1893, and lots of different metals – from silver to aluminium, lead to copper – possess it.

So the question is: why aren’t the hand poles in Underground cars and on buses made of antimicrobial metal?

 

A Santiago metro station, complete with bacteria-killing handrails. Image: AntiMicrobialCopper.com.

In some parts of the world, the answer is actually “they are”. The subway system in the Chilean capital Santiago, for example, uses antimicrobial brass handrails, which were installed in 2011 as part of a wider healthcare campaign. But this is an exception, not a rule.

Jean-Yves Maillard is a pharmaceutical microbiologist from the Cardiff University who researches the use of antimicrobial materials in hospitals, and specifically the two most promising metals: silver and copper (or alloys of copper, rather). It turns out that these things kill germs best when “humidity is 100 per cent, so they are underwater – and that’s not how these surfaces exist on the metro, or Tube, or buses.”

Instead, to get a better idea of how well they work, he’s tested them when they’re dry (which means between 30 and 40 per cent humidity, which is typical for the UK), and when they have “droplets” (i.e. someone’s sneezed) on them.

The results are still impressive: within 30 minutes of contact with the most effective copper alloys, 99.99 per cent of Staphylococcus aureus bacteria – a bug responsible for everything from skin infections to respiratory diseases, and including the infamous antibiotic-resistant MRSA strain – were exterminated in the droplet test, while the dry test still saw around a 90 per cent reduction.

“When it's very dry – the worst case scenario, a very dry summer and so on, above 20 degrees – you'd get something like 99.99 per cent reductions within 30 minutes,” he said. “If someone sneezes, then after 30 minutes on that surface the bacteria is likely to be killed. I imagine for some viruses it would be the same as well. [But] if you haven't got droplets, then that activity really drops sharply. You'll get at most 90 per cent reductions, but probably less than 90 per cent, within 30 minutes. You'll kill some, but not all.” Silver was less effective in the droplet test, and not effective at all in the dry one.

This might make switching to copper-based antimicrobial subway and bus poles seem like an easy win that TfL missed when ordering its newest trains. But Maillard is keen to stress that there are some important downsides.


It rhymes with "fromage"

Firstly, if a surface is cleaned relatively frequently, then the extra cost from using more expensive materials might be more than those of simply paying for someone to wipe everything down a bit more frequently each day, for the same result. And these surfaces are no substitute for cleaning – Maillard emphasises that antimicrobial surfaces work “in addition” to cleaning, not as a replacement. And, when I contacted TfL, health & safety director Jill Collis made it clear that they clean the network “throughout the day and night” already.

The second reason is appearance. According to Collis, “the handrails in carriages are designed to be easy to see, meet safety standards and be suitable for daily use by millions of customers”. (I also discovered that the internal TfL term for the things that passengers hold onto isn’t “handrails”, but “grippage” – pronounced to rhyme with “fromage”.)

This is an important point – and TfL also said that, in accordance with the Vehicle Accessibility Regulations Act 2010, “any passenger handrail fitted in or to a rail vehicle must … contrast with the parts of the rail vehicle adjacent to that handrail”.

In other words, the bright colours on the Tube are primarily so that the visually-impaired are better able to see them. While the brass handrails of the Santiago subway may look somewhat classy, they also blend into the background in dark, underground spaces.

A third important issue is value for money. The handrails on the Tube are made of aluminium, which has a good ratio of weight to cost to strength; copper and silver, less so. “In hospitals, the debate is all about costs,” Maillard said. “[Surfaces] maybe get cleaned once a day, and with copper surfaces there are indications that at the end of the day the [the microbial burden] will be less than normal metal surfaces. That's the interest in it. But the big question is, is it cost effective?”

Then there’s even a fourth issue, most relevant to silver, which is that it perversely seems to make drug-resistant superbugs more likely. Making subway poles out of solid silver is, clearly, ridiculous, but it’s common for nano-particles of silver to be placed within other material to give it some antimicrobial properties – not as good as copper alloys, of course, but still something.

Maillard points to a January 2015 report from the EU Commission’s Scientific Committee on Emerging and Newly Identified Health Risks (Scenihr) into the possible dangers posed by the use of nano-silver in medical and consumer devices. It found that research is “urgently needed” into the possible toxic effects of long-term exposure to silver in consumer products, and also that the genetic adaptation of bacteria to silver could increase resistance.

“What you will find is that now you have a huge amount of surfaces that contain antimicrobials,” Maillard explained. “Lots of plastics, washing machines, photocopiers, in pens, televisions, television remote controls – most of them contain silver or nano-silver, because they don't affect the colour. The concentration that they use is very low, there are question marks over its efficacy, and questions about whether it's going to promote resistance of those organisms with those products.”

So, put it all together and it doesn’t look good for Tube poles that clean themselves. Copper alloys work best, but would have to be painted to comply with health & safety legislation, defeating the purpose. And, while it’s possible to stick silver particles into the paint as an alternative, it’s not very good, especially when the extra cost is factored in – and that’s without considering make it more likely that truly nasty bacteria can thrive and evolve on public transport.

Best stick to hand sanitising gel. Much easier.

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In many ways, smart cities are really very dumb

Rio de Janeiro’s control centre. Image: Getty.

It’s not news that anything and everything is increasingly being prefaced with “smart”: phones, watches, homes, fridges, and even water (yes, smartwater exists). And it’s not unintentional either. 

Marketeers know that we, the public, are often stupid enough to believe that thanks to their technology, life is better now than it was way back in, say, the primitive Nineties. Imagine having to, like a Neanderthal, remember how to spell words without an autocorrecting algorithm, or open the fridge door to check if you’d run out of milk, or, worse still, interact with actual people.

So it’s hardly surprising that we’re now also witnessing the rise of the so-called “smart cities”; a concept which presupposes that cities that are not technologically  “smart” are dumb, which, as anyone interested in the millennia-old history of cities — from the crypto-currency grain storage algorythms of ancient Mesopotamia to the complex waste infrastructure of ancient Rome, to London’s public transport infrastructure — will know, is not true.

Deployed in these smart cities are cameras and other networked information-gathering devices, load cells and other “sensing devices” detecting passing pedestrians and vehicles, audio surveillance devices listening for gunshots – and even vending machines equipped with biometric sensors to recognise your face. This is not to mention beacon technology — tiny anonymous looking black boxes hidden in trees and on lampposts — which transmits advertising, offers and other information directly to smart phones in the vicinity. 

If that doesn’t seem sinister enough, take, for example, Rio de Janeiro, where, in 2014, the International Business Machines Corporation designed a mammoth “control centre” that integrates data from 30 agencies for the city’s police. 

Described by the Guardian as having “the functionality of a Bond villian’s techno lair”, the then local mayor, Eduardo Paes, claimed the centre was making the city safer while using technology to deploy its “special” police unit to carry out the state’s “pacification programme”. Launched in 2008, the programme, which aims to push out drug gangs from Rio’s favelas, has been criticised by Amnesty International: “in January and February 2017 in Rio de Janeiro alone, at least 182 people were killed during police operations in marginalized neighbourhoods (favelas) – a 78 per cent increase in comparison to the same period in 2016”.

Sinister or not, as smart cities grow, they create new problems. For example, as urbanist Adam Greenfield writes in Radical Technologies: The Design of Everyday Life, neither the algorithms nor their designers are subject to the ordinary processes of democratic accountability – a problem that international academics are currently attempting to tackle.  


“We need to understand that the authorship of an algorithm intended to guide the distribution of civic resources is itself an inherently political act,” writes Greenfield. “The architects of the smart city have utterly failed to reckon with the reality of power.”

The Real Smart Cities project, founded by Dr Gerald Moore, Dr Noel Fitzpatrick and Professor Bernard Stiegler, is investigating the ways in which so-called “smart city” technologies present a threat to democracy and citizenship, and how digital tools might be used create new forms of community participation.

Fitzpatrick is critical of current discourses around smart cities, which he says “tend to be technical fixes, where technology is presented as a means to solve the problems of the city.” The philosophy underpinning the project is “that technologies function as forms of pharmacology”, he adds, meaning that they can be both positive and negative. “The addictive negative effects are being felt at an individual and collective level.” 

An example of this lies in the way that many of these smart cities replace human workers with disembodied voices — “Alexa we need more toilet roll” — like those used to control the Amazon Echo listening device — the high priestess of smart home. These disembodied voices travel at the speed of light to cavernous, so-called “fulfilment centres”, where an invisible workforce are called into action by our buy-it-now, one-click impulse commands; moving robotically down seemingly endless aisles of algorithmically organised products arranged according to purchase preferences the like of which we never knew we had — someone who buys a crime novel might be more likely to go on and buy cat food, a wireless router, a teapot and a screwdriver. 

Oh to be the archeologists of the future who while digging through mounds of silicon dust happen upon these vast repositories of disembodies voices. That the digital is inherently material and the binary of virtual/real does not hold — there is no cyberspace, just space. Space that is being increasingly populated by technologies that want to watch you, listen to you, get to know you and sense your presence.

One project looking to solve some of the problems of smart cities is that of the development of a “clinic of contribution” within Pleine Commune in greater Paris (an area where one in three live in poverty).This attempts to deal with issues of communication between parents and children where the widespread use of smartphones as parental devices from infancy is having effects on the attention of young children and on the communicative abilities between parents and children. 

This in turn forms part of a wider project in the area that Stiegler describes as “installing a true urban intelligence”, which moves beyond what he sees as the bankrupt idea of smart cities. The aim is to create a “contributory income” in the area that responds to the loss of salaried jobs due to automation and the growth and spread of digitisation. 

The idea being that an income could be paid to residents, on the condition that they perform a service to society. This, if you are unemployed, living in poverty and urban deprivation, sounds like quite a simple and smart idea to try and solve some of the dumb effcts of the digital technology that's implemented in cities under the ideology of being “smart”.