Saturday 24 January 2015


Electronic cigarettes, or e-cigarettes have become commonplace as a safer substitute for the real thing. But are they safe to use?

One important consideration is that at the moment e-cigarettes are not regulated in many countries, including the UK. This means, like all unregulated products that have a potential health risk, you don't know that what you are using contains only what is supposed to contain. There is no magic wand for this, apart from buying from legitimate brands, ideally through a known major retailer, who will hopefully have done some checks for you.

The liquid you put in an e-cigarette (assuming it's a legitimate one) has nicotine, extracted from tobacco, flavourings and suspension fluids that work well with the vaporising process, typically propylene glycol and glycerol which in themselves are both pretty much harmless.

When you inhale this stuff, either actively or as a passive recipient of someone else's vapour, you are taking an aerosol - fine droplets of liquid - into your lungs. This can happen perfectly naturally, for instance with some strong-smelling natural substances. But having unwanted material in the lungs always has the potential for risk, specifically for causing cancer.

The biggest concern here is not the original chemical constituents, but rather than the heating process that sends the vapour out can break down some of the suspension fluid into formaldehyde. In small quantities this isn't a problem - our bodies deal with formaldehyde all the time - but in larger quantities formaldehyde is a carcinogen, particularly around the respiratory system.

At this stage there hasn't been enough research to confirm the early findings, but if the data available so far is correct, heavy users of e-cigarettes could have a significant cancer risk - possibly as high a risk as from smoking in the first place. In the balance, cigarettes have a whole range of negative impacts, not just lung cancer, so this isn't an argument for going back to smoking cigarettes. And if an e-cigarette is used as a vehicle to fairly quickly stop smoking altogether, on balance it may be worth using (though patches, gum and other sources of nicotine don't carry this potential risk).

However, what this does suggest is that no one should use e-cigarettes just for the sake of it, and should only consider using them in a tapering off programme to quit smoking if options like patches and gum aren't working. And it also means we ought to see e-cigarettes banned from all the locations we ban conventional cigarettes - as the risk from passive inhalation is certainly present.

For the future there are a number of steps that should be taken. E-cigarettes should be regulated and licensed as vehicles for drug dispensing. There needs to be significantly more research into the production of formaldehyde and any other potentially dangerous substances. And there should be research into safer suspension fluids.

The principle of e-cigarettes is good, but there is evidence that this still very young product needs significantly more work to ensure that it is a safe substitute for tobacco.

Thursday 8 January 2015

Screens and eyes

For as long as we’ve had televisions they have been accused of damaging our eyes – but now, with screens everywhere, what’s the true picture?

When I was young, older people were always telling us not to sit too close to the TV or to spend too much time watching it. Yet back then, we only had a fraction of the screen time that most of us experience today. You may well spend all day at work looking at a computer screen, then come home to spend the evening in front of the TV. And what were you doing in between these times? Looking at your phone or tablet.

In 2014 there was a scare story that overusing smartphones may damage the eyes. The concern was that the light from LED screens contains more blue/violet light than the natural light that best suits our eyes, and the higher energy blue/violet light can overload the sensors on the retina, increasing the risk of macular degeneration, a common cause of blindness.

The story particularly highlighted the risks from smartphone use, where the screen is held considerably closer to the eyes than a computer or TV screen and is often used in lower lighting condi- tions, where the dilated irises of our eyes allow more light in.

We have to approach this story with a little caution. There is no study showing that exposure to screens, even smartphones, causes eye problems – this is extrapolating from laboratory-based evidence that light in this region can cause damage to the type of cells used in the retina. So at the very most, this is a precautionary warning as yet.

What is certainly true is that our eyes don’t respond well to being focused as closely as a smartphone requires (TVs are usually positioned at a better distance) for long periods of time, and this can cause eye strain. Taking a break from screens for at least five minutes in each hour, and a few longer breaks during the day is highly recommended. Furthermore, regular screen users – which is pretty well all of us – should have regular check-ups with an optician.

UPDATE: In December 2014 a different study showed that people who read backlit screens in before going to sleep produced less of the hormone melatonin. This can make it harder to get to sleep, and in the long term, sleep deficiency can produce significant health problems. As yet the evidence is relatively limited - this was a very small study with just six people on each kind of book. However if you do have trouble getting to sleep, and you read from a screen for your bedtime reading it is worth switching to a paper book (or an e-ink reader like a basic Kindle that doesn't have a backlight) to see if it helps make sleep more easy. Ideally avoid close backlit screens (including phones and computers as well as tablets and backlit e-readers) for a couple of hours before trying to sleep. TVs don't seem to be a problem as we don't sit anywhere near as close, so the blue backlight is a relatively small part of our incoming light - and the generally darker coloured picture of video is better than the stark white of a page to read. If you have to use a backlit e-reader, try turning down the brightness.

Wednesday 7 January 2015

The numbers game

The media, politicians and interest groups love to throw numbers at us to support their cause - and they can be very useful - but we always ought to ask: 'Where did those numbers come from?' and 'What does that actually mean?'

Here's a good example. In 2015, a website attacked the UK Labour Party's policy on arts funding pointing out 'Just so you know, arts funding brings in £4 for every £1 spent.' It's quite likely this statistic will get a life of its own and be used many times in the future. But what does this actually mean, and where did the numbers come from?

As far as a source, the figure seems to be genuine. After following a chain of different people using it, it originated in a 2013 report by Arts Development UK. So I was, with a little work, able to check where it came from. Yet the chances are, when a figure like this is used, it will often not be possible to easily find out its exact source.

And what does it actually mean? I asked quite a few people who all, like me, assumed that the claim 'arts funding brings in £4 for every £1 spent' meant that if you fund the arts, for each £1 you spend, £4 will come in either directly (through entrance fees, brochures etc.) or indirectly (for instance by more tourists coming and spending money in your town or city). But look at that original report and you'll find something entirely different was intended.

The report says 'For every £1 spent by local authorities on arts service, leverage from grant aid and partnership working brings in £4.04 of additional funding.' So, when a local authority spends £1 it gets that additional money from grant aid and partnership - which is largely with other authorities and with bodies like Arts Council England. In other words, £1 of local government spend brings the local authority another £4 of public money. Excellent for the local authority, but hardly supporting the argument in which it was used. Whether intentional or (probably as here) accidental, this is a kind of deception.

We usually don't have the time to trace back a statistic to its source like this - but don't be taken in by numbers picked out of the air. Anyone who uses numbers like this should expect to have them challenged - and needs to be able to show exactly what they mean and where they come from.