Archive for May, 2007
If the Independent is intent on shredding any scientific credibility it once had, last weekend was a bold step toward that goal. No less than three pages (including the front page) were dedicated to whipping parents into a frenzy over the soft drink preservative sodium benzoate, which they claimed was suspected of being able to damage cellular DNA. The story, a winning combination of health scare, popular foodstuff, children, anti-oxidants, chemicals, E-numbers, premature ageing, and of course, “science”, proved irresistible to journos everywhere, or at least here, here, here and the Daily Mail’s subtly titled version, Chemical in soft drinks ‘can wreck your child’s DNA’, here. Big news indeed.
So what’s the story? Over to Martin Hickman at the Independent:
Research from a British university suggests a common preservative found in drinks such as Fanta and Pepsi Max has the ability to switch off vital parts of DNA.
The problem - more usually associated with ageing and alcohol abuse - can eventually lead to cirrhosis of the liver and degenerative diseases such as Parkinson’s.
Wowsers! Pretty grim stuff. The research isn’t cited, but it belongs to one Professor Peter W. Piper, an ‘expert in ageing’ at Sheffield University. Professor Piper published a study detailing the effects of sodium benzoate on yeast cultures. He found that the sodium benzoate had a toxic effect on the yeast, part of which involved damage to the yeast cells’ mitochondrial DNA and a rise in oxidant action. It’s all very complicated, and I don’t fully understand it, but you don’t need to be an architect to spot something wrong with the Leaning Tower of Pisa, so to speak.
So here are the facts: sodium benzoate is a preservative added to soft drinks to prevent mould. Professor Piper performs an experiment which shows that yeast (a kind of mould, lest we forget), doesn’t do well when sodium benzoate is mixed in with it. I think I speak for everyone when I say “well, duh!”.
But that’s not a story. A story involves a human cost, and somewhere along the way, someone has confused yeast with humans and decided that E211 poses a threat to us all. I tried to track down the source of the news, and I found it[1]. I have a copy, I can’t share it because it’s under copyright, but here’s the bit that you need to know: no humans. Just yeast.
And there’s another problem: the research was published 8 years ago. There’s been no research since, to my knowledge, by Professor Piper or anyone else. So why has this story only hit the stands now? The answer lies in a press release summing up the threat in an easy-to-digest manner, authored by none other than Professor Peter W. Piper himself! You can see read press release for yourself here. It is dated 21/05/07, a little over a week ago. So now the question is, why has Professor Piper seen fit to publish a press release for his own 8 year old research? Over to the professor himself:
I published this - firm scientific evidence that benzoate can cause cell damage, at least in the laboratory - at the time, in the hope that the food industry and regulatory authorities would take the matter seriously. Instead they have chosen to hope that my work fades into obscurity and hide behind safety tests largely done ~50 years ago that would not have detected the damage I describe.
Ouch, sounds like someone has a chip on their shoulder. Now let us be very clear on this: as far as I can tell, Professor Piper has not performed any bad science within the context of his study. That much I can say.
However, Professor Piper has seen fit to whip the newspapers into a frenzy about a possible indication of his work. Sodium benzoate is not good for yeast. That much is obvious. But does E211 have the same effect on mitochondrial DNA in human cells? There is no evidence that it does. Would it happen on exposure to levels of sodium benzoate found in soft drinks? We don’t know. If it did, would these effects be severe enough to be considered harmful to our health? Nobody knows.
If you think I’m downplaying the risk, here’s the professor himself:
There is no firm evidence that benzoate causes significant damage in man, but in view of the above it is probable that it will cause some damage, although whether levels are significant is unproven/untested.
You won’t find that in the press release. Professor Piper stopped replying to my emails before I could ask why he chose to create this controversy. Perhaps he feels it is worthy of further study - I certainly do. But the way to go about that is to set out good scientific studies and perform them, not to whip up hysteria over some tenuous hypothesis in order to elicit funding. That’s unprofessional, unethical and unkind.
There is no evidence to suggest E211 is harmful to humans. That is the bottom line. When Professor Piper demonstrates toxicity of sodium benzoate in humans at levels found in soft drinks, I’ll shout it to anyone who’ll listen. But not until the evidence is in place. Until then, this stands as a sad example of cynical exploitation of the media, and is made especially galling by his recommendation that children avoid soft drinks, which plays ruthlessly on parents’ anxieties. This manipulation is something the Independent have opened themselves to through an utter lack of scientific literacy or desire to apply it. This is the state of science reporting in the UK today, and it’s enough to make me cry.
[1] Piper, P.W. (1999) Yeast superoxide dismutase mutants reveal a potent in vivo prooxidant action of weak organic acid food preservatives Free Radic. Biol. Med. 27, 1219-1227.
May 29th, 2007
It’s hard to debunk news articles sometimes when they are such a blur of reason and conjecture that it’s no longer clear what the point of the story is. Here’s a classic example that caught my attention during my morning muesli.
Apple juice ‘may prevent asthma’ - BBC
Children who drink plenty of apple juice may be less likely to develop asthma symptoms, say scientists.
The National Heart and Lung Institute research, published in the European Respiratory Journal, is the latest study to link apples and lung health.
Sounds pretty good to me - apple juice is cheap, kids love it, and look at the first line of the article - “say scientists”! Scientists. They say it. It must be true. But then as we read through the article, this troubling fact crops up:
While no link was found between apple juice consumption and a reduced chance of an actual asthma diagnosis, the link between wheezing and drinking the juice was quite strong.
Wait, come again? No link… between apple juice consumption… and reduced chance of asthma. Hmm. That kind of contradicts the general tone of the article. No link, huh. Hmm. And then they start throwing in the curveballs:
A similar, but weaker, benefit was found for children eating bananas at least once a day compared with less than once a month.
Wait, bananas? I though this was about apples? Or more specifically, apple juice. Of course, apples and apple juice are just as good as eachother, right?
Eating fresh apples themselves gave no apparent benefits, the study concluded.
WTF?
[Dr Peter Burney] said it wasn’t clear why a link between eating apples themselves and reduced asthma symptoms - already spotted in other research in adults - did not appear among these children.
?!
Research from the university published last week suggested that women who ate plenty of apples during pregnancy were protecting their unborn children against asthma later on.
??!! Argh! This article is so damn confusing it makes my head hurt. So, in summation, we can could chose to say “Apple juice ‘may prevent asthma’”, as the BBC did. Or we could say: “Apple juice may reduce the wheezing associated with asthma, but it won’t actually reduce your chances of an asthma diagnosis. Eating apples won’t do, unless your mum eats them when you’re still a foetus, or maybe if you’re an adult, according to someone else. But between birth and puberty, juice is where it’s at. Eating bananas is also good. But we’re not sure why.”
It’s reasons like this that I rarely read the health pages, let alone try to sciencepunk them.
May 29th, 2007
Thanks to BoingBoing for making me aware of this awesome website where you can buy t-shirts with anatomically correct, lifesize drawings of your bones, nerves and other biological systems. I’ve already bought the skeleton shirt and I’m looking forward to when the x-ray shirt hits the stands. Ace!
May 28th, 2007
This has to be, in my opinion, the best job in the entire universe.
Video now fixed!
May 26th, 2007
Blogger Martin Davies has an amusing (if somewhat brief) exchange with a Metro journalist over their description of liquid nitrogen as a gas.
Everyone knew what we meant by ‘gas’ - even if it was wrong scientifically - and that is the purpose of communication, the business we are in.
I replied:
What did you mean by “gas” if not “gas”? Surely using a word correctly is at the very heart of communication?
Taking back science with patronising humour? That’s the kind of sciencepunking we like to see! (link)
May 25th, 2007
The blogosphere is in uproar over the recent Panorama show titled: “Wi-Fi - A Warning Signal”, which, despite offering absolutely no evidence of any risk whatsoever from wi-fi networks, still saw fit to spend an hour scaremongering about the subject. You can see the original program here or read the short BBC News story that goes with the program here.
There’s little I can add to the debate at this point, except maybe to collate a few of the more interesting points for your easy digest. We were shown by “expert” Alisdair Phillips that levels of “electrosmog” in the classroom (from wi-fi) were three times higher than those in the playground (from a phone mast). That these levels were still 600 times below the accepted safe limit was not dwelled upon. That Alisdair Phillips is better known as the man who sells tin foil hats was not mentioned at all.
Panorama’s case hinged largely upon the revelation that the Swedish government recognises electrosensitivity as a disability affecting 3% of the population. However, Swedish resident DennisJ reports the following:
* In 2004, Olle Johansson, who appears as an expert in the program, was awarded Misleader of the Year 2004. In reality he’s not much of an expert at all.
* I have found no indications that there are such things as official disabilities in Sweden or that “the Swedish government recognises radiation sensitivity as a disability.” What have happened is that the government has granted various kinds of support to “electrosensitives”. But it doesn’t mean that electrosensitivty exists, The National Board of Health and Welfare seems to regard it as an psychosomatic illness.
* That it affects 3% of the population is perhaps a half truth at best. 3 percent of the participants said in a survey that they were sensitive to, oversensitive to or allergic against electric or magnetic fields. One tenth of those was in a severe situation, and it’s not clear that even all of those should be regarded as disabled. The Swedish association for the elctrosensitives has, in comparison, 2400 members.
Finally, a bit of original research from myself. Professor Henry Lai of Washington University was presented as an expert in the field of bioelectromagnetics who claimed to have found health effects at similar levels of radiation to wi-fi, stating that thousands of papers had shown an effect. A few minutes on Google, however, and some interesting facts crop up. Firstly, Professor Henry Lai earned a PhD in psychology, not biology or electromagnetics. Secondly, one of the papers showing these effects was co-authored by himself and a man called Professor Bill Guy. This showed that spatial learning in rats was negatively affected by a certain form of radiation. Guy has since retired, but when he discovered Lai using this paper to illustrate the dangers of mobile phone technology, he had to explain to Lai that the findings were not applicable to mobile phone use at all, but to radar.
That wi-fi is simply radio waves, the same kind of radiation that has been pulsing through us for the last hundred years, the same radiation that brings us wonderful TV signals like, er, Panorama, was not dwelled upon, or even seen fit to mention. Panorama’s argument seems to be based on the idea that just because there’s no credible evidence of wi-fi being dangerous, doesn’t mean it’s safe. No-one’s yet conclusively proved that electricity won’t suddenly disobey physics, grow heavy and fall out of power lines. Do you think we should ban electricity until we can prove this won’t happen?
So there you have it. The army of blogs thrown up in the spare time of amateur scientists really can perform better researched, more unbiased journalism than the BBC. Join the revolution, my friends.
May 24th, 2007
From the BBC:
A scientific exploration of the various ways people attempt to make themselves happy has won the annual Royal Society Prize for Science Books.
It beat five other titles including Henry Nicholl’s Lonesome George, an account of the last known individual of a subspecies of Galapagos tortoise.
May 16th, 2007
Paul Kammerer was an Austrian biologist who studied Lamarckian inheritance, who in his lifetime found fame and success and subsequently disrepute and death, in a story involving evolution, Nazis, suicide, India ink and the humble Midwife Toad.
Continue Reading May 15th, 2007
Combining two of the Daily Mail’s favourite subjects - cancer and nubile young women, Broken Hut has an excellent post discussing the bad science and bad morality surrounding opposition to teenage girls receving a vaccine which protects against the Human Papilloma Virus (responsible for 70% of cervical cancer cases in Britain). The logic goes, HPV is a sexually transmitted infection, therefore vaccinating girls will encourage them to have sex. Of course. Much in the same way tetanus boosters encourage people to stab themselves with rusty nails. Of course, this is different, because stabbing oneself with a rusty nail is perfectly acceptable, but God forbid teenage girls start having sex. That would be the end of the world.
Ithika’s discussion is here, I encourage you all to read it.
May 14th, 2007
When sitting down to a horror film, I invariably plump for a zombie film. I think it’s because it’s so hard to imagine how a shambling, rotting corpse could be a threat to anyone, but somehow it always ends up this way. I was intrigued by how many films depict survivors barricading themselves in makeshift fortresses, only to await their eventual demise. As a fan of medieval warfare (perhaps it’s all these castles here in England), I also recognised how the principles of siege warfare didn’t support defence against an undead threat.
In the context of this essay, we’ll assume for the most part that our enemy is the classic zombie - undead, slow, of low intelligence but possessed with reasonable strength and unlimited stamina. I’ll also be assuming second-generation epidemiology for these creatures - rather than servants under the control of a mage, our zombies are of biological genesis and their epidemiology follows a viral pattern of infection - the recently deceased may awaken, and infection spreads through bites and exhibits 100% infection and mortality rates, resulting in a exponential morbidity pattern within the human population. Now, onto medieval warfare…
A siege occurs when a defending fortress refuses to surrender and cannot be easily taken by a frontal assault. The attacking army block both the escape of the defenders and prevent reinforcements and supplies reaching the besieged army. Thus, a war of attrition develops, and if neither army can gain a significant military advantage, the result is often decided by famine or disease.
Traditionally, the attacking army will attempt to circumnavigate their target’s defences by infiltration, sapping (tunnelling under walls to collapse them), artillery bombardment or siege engines (battering rams, trebuchets, etc). Given the typically low intelligence of zombies, sophisticated siege weaponry and tactics are unlikely, although rudimentary coordinated attacks are sometimes seen - the setting of an ambush in Return of the Living Dead, for example. Also, the danger of infiltration must not be underestimated, as a single zombie inside the fortress can quickly escalate into a catastrophic situation (28 Days Later, Night of the Living Dead).
There are four possible outcomes to a siege. Firstly, the defending army are rescued by an outside force, who defeat the encamped aggressor (both the 1683 Siege of Vienna and the 1899 Siege of Mafikeng ended this way). This is probably the outcome that most survivors of zombie attacks are hoping for when they decide to take refuge in an abandoned shopping mall or old house. In the early stages of an outbreak, rescue by local police or a militia is fairly likely (Night of the Living Dead, Children of the Living Dead). However, as time passes, not only does the likelihood of rescue diminish, but the zombie threat increases, entrenching the defenders in their hastily-assumed position.
Secondly, the defenders may chose to engage the attacking army. Historically, this almost always ends in the annihilation of the defenders - who, by definition, are not organised for open combat. However, even after a protracted siege, Soviet forces were able to force a break in the German encirclement during the 1941 Siege of Leningrad. In fiction, attempts to break sieges are often taken by heavily-armed defenders fighting their way out of a fortified compound (Dawn of the Dead, Night of the Living Dead). However, there exists a narrow window of success for this strategy, as over time the zombie army perpetually grows in size while the resources of the survivors are diminished.
The third outcome of a siege is that the attacking army exhaust their resources and are defeated by starvation or disease. Clearly, this is extremely unlikely with a zombie threat. Lifespan of a zombie is uncertain, ranging from around two months for the sub-living (28 Days Later) to months and maybe years, depending on conditions. Even with this limiting factor, survivors must have resources (food, water, medicine) within the compound to outlast the undead threat.
Finally, and most likely, is that the besieged army succumbs to starvation or disease, and is overrun by the attacking army. Only the most well-prepared defender can hope to outlast a significant zombie outbreak, and even then must rely upon the eventual second death of the zombie army. In addition, the threat from within must not be underestimated as the strain of a long-term siege takes its toll on the mental stability of the survivors. Infighting can quickly lead to sectarian violence as survivors divide into broad classes (28 Days Later, Land of the Dead). This is compounded by the inevitable influxes of refugees (Dawn of the Dead) as smaller, nearby fortresses are overwhelmed by the attacking force. These refugees will not only tax the limited resources of the defenders, but bring the threat of infection into the compound.
So what is to be done in the event of a zombie outbreak? For small scale threats, it is almost always better to organise a militia and meet the undead face-on. When under attack by a limited force of zombies, the undead threat should be contained and destroyed. The predilection of zombies to congregate can be used to the defender’s advantage here, typically by luring the attacking army into a killzone (Return of the Living Dead Part 2, Chopper Chicks in Zombie Town).
However, in the event of a larger outbreak, or where resources do not permit an organised militia, survival strategy favours small, mobile groups that can evade zombies forces and relocate easily once a position becomes untenable (28 Days Later). Much in the same way that the ability to deliver huge destructive power (aerial bombardment, ICBMs) made well-fortified static defences obsolete in the early 20th century, the resistance of zombies to hunger and exhaustion, and their unique biology that allows unrestricted population growth, renders any long-term advantage of siege to nil. In order to survive a zombie outbreak, readers are encouraged to concentrate on remaining flexible and highly manoeuvrable, retreating quickly to areas of low population density, and to seek contact with greater military force.
Of course, in the event of a major zombie outbreak, the global fall of mankind to the walking dead is almost inevitable, so a noble last stand may be preferable to those of a cinematic inclination.
May 11th, 2007
Nature has a brief interview with Martin Nicholas, a water treatment plant salesman who moonlights as an expert spider hunter. Not content with discovering several new species, he travelled to Peru in search of the legendary Chicken-Eating spider, a gigantic arachnid capable of taking down a full-grown hen. What he found was a monster 10 inch black tarantula, possibly a new species. Martin says:
“It looks like when they go out at night as a group, they can catch and kill larger prey by working together.”
Cripes! I think I speak for us all when I say: “Nuke ‘em from orbit, it’s the only way to be sure”.
May 8th, 2007
The BBC is currently featuring an article on the strange and beautiful Solúcar Energía power plant in Andalusia. Sunlight is reflected by 600 huge mirrors, each measuring 120m2(!!), onto a 40-storey high tower, delivering a massive 11MW of energy from steam turbines. Not only is this an incredible achievement of science, it’s utterly beautiful.
Solúcar Energía homepage (Spanish/English)
May 3rd, 2007
While I’m busy moving house, please enjoy this classic SciencePunk article. Normal service will resume once I get my “office” unpacked.
Ulysses Morrow was a newspaper editor, inventor, and geodesist, who was asked by his friend Cyrus Teed to scientifically prove that the surface of the world was concave. Not only did Morrow accept this challenge - he succeeded in proving the inward curve of the Earth’s surface. This became known as the Naples Experiment.
Continue Reading May 2nd, 2007