More sorry than safe
Professor Sir Colin Berry says our obsession with the precautionary principle is making life more dangerous.
‘If everything we did had to be absolutely safe, risk-free, proven to have no adverse outcomes for anyone or anything, we’d never get anywhere. Buildings wouldn’t go up, planes wouldn’t get off the ground, medical breakthrough would come to a standstill, science would be stifled…. Shall I go on?’
Professor Sir Colin Berry is not a big fan of the ‘precautionary principle’, the idea that scientists, medical researchers, technologists and just about everybody else these days should err on the side of caution lest they cause harm to human health or the environment. Berry is one of Britain’s leading scientists; he has held some of the most prestigious posts in British medicine, including head of the Department of Morbid Anatomy at the Royal London Hospital from 1976 to 2002. Now he watches as his ‘good profession’ threatens to be undermined by what he says is an ‘unscientific demand’ to put precaution first.
One of the most common definitions of the precautionary principle is that put forward by Soren Holm and John Harris in their critique of it in Nature magazine in 1999: ‘When an activity raises threats of serious or irreversible harm to human health or the environment, precautionary measures that prevent the possibility of harm shall be taken even if the causal link between the activity and the possible harm has not been proven or the causal link is weak and the harm is unlikely to occur.’ For Berry, this is one of the biggest problems with the precautionary principle – the notion that we could ever fully predict the outcome of an experiment or piece of research before it is complete, and that if we can’t then we should play it safe. ‘It doesn’t allow for the unknown’, he says. ‘Or for taking a risk in order to do something potentially useful.’
Berry says it is in the nature of scientific and medical research that you start out before you have all the information to hand – indeed, almost all of the great scientific advancements of the past 200 years have been a process of ‘learning as we went along’. ‘Consider blood transfusions’, he says. ‘When we started doing them, we knew about some blood groups but there were others we didn’t know about. We only came to know of these other blood groups when patients started to have transfusion reactions. There was an unknown, but we were able to learn from it and refine the process.’
He wonders whether, if the precautionary principle had been about for the past 200 years rather than the past 20, breakthroughs such as blood transfusions would ever have been made. ‘I certainly don’t think we would have radiotherapy or the various applications of x-rays if Marie Curie had been under pressure to comply with the precautionary principle’, he says. In the early twentieth century, Polish-born physicist and chemist Curie devoted her working life to the study of radium, paving the way for nuclear physics and the treatment of cancer. It cost her her life – she died from leukaemia in 1934, almost blind, her fingers burned by radium. ‘Curie’s work caused her “irreversible harm”’, says Berry. ‘The precautionary principle would not have permitted her to take such risks, and the world would have been a worse place for it.’
Berry says that when he challenges ‘our obsession with safety’, some imagine that he is leading the charge for being reckless, for throwing caution to the wind, as the saying goes. He insists that isn’t so. ‘Precaution is a part of everyday life. It is sensible to do things that minimise risks to ourselves and to others. You shouldn’t close your eyes when you cross the road; you should stub out your cigarette before going to sleep.’ But, says Berry, problems arise when precaution is transformed into an abstract principle that we’re expected to live our lives by. ‘Safety is a description of an approach, rather than an absolute state’, he says. ‘We can never be absolutely safe and free from risk. Indeed, aspiring to such a state brings its own problems.’
For Berry, there is a great irony in the precautionary principle – it causes its own harm; our obsession with keeping safe can have the effect of exposing us to new dangers. On a simple, everyday level, he cites the example of the choices we make about commuting. He says that those who opted to travel by road rather than rail following the Hatfield train crash of October 2000, which killed four passengers and injured 30, had in fact exposed themselves to an increased risk of injury or death. ‘Road accidents kill more people than railway accidents do’, he says. ‘Yet because there is a perception that rail travel is unacceptably risky, some people opt to go by car instead. But the death rate on the road per billion person miles travelled is about 12 times that of the railways.’
Berry says the precautionary principle has a similarly ironic and detrimental impact in the world of medicine. As a father, grandfather and doctor who started his career at the Institute of Child Health at Great Ormond Street, Berry has a special attachment to child health. Later this month, the World Health Organisation is hosting a conference in Budapest under the heading ‘Children’s heath and the environment’, where some of the great and the good of the children’s health world will debate what kind of precautionary measures can be taken to ensure that children around the world ‘grow in an environment that allows them to reach their highest attainable level of health’. Berry is all in favour of giving children, wherever they are, the best healthcare – but he argues that precautionary measures, without the backing of evidence and data, are not always the solution.
He cites the controversial issue of SIDS – Sudden Infant Death Syndrome, aka cot death – about which parents are given lots of often contradictory advice. Berry says that in the 1980s, the favoured precautionary measure to guard against the possibility of your baby falling victim to SIDS was to lay her on her side or front. ‘We tended to consider babies and young infants as being rather like the unconscious patient’, he says, ‘where it is not clear that all the reflexes around the nose and mouth, for breathing and swallowing and so on, are finely tuned. So parents were told to put babies on their side or front, as you would do with an unconscious or stroke-troubled patient. It seemed like a reasonable, precautionary measure to take. Now we know that, in fact, it cost lives.’
Berry says that subsequent observations made in Australia and New Zealand, and a case-controlled study in Britain in the 1990s, showed that reversing this policy and putting babies to sleep on their backs instead reduced the death rate from SIDS. In the UK, it fell from about 1,300 to 1,400 a year to about 300 to 400, he says. ‘With the best intentions the precautionary measure of putting babies on their sides or fronts caused misery; a great many precious baby lives were lost because of what seemed like a reasonable precaution. It was one of those things that just happened to be wrong. This shows that we need data – that being precautionary, taking safety measures without testing the evidence, is not enough.’
For Berry, the precautionary principle most clearly becomes a potential life-threatener when applied to the third world. He becomes especially animated when we discuss the outbreak of cholera in Peru in the early 1990s. In 1991, an epidemic of cholera, which had earlier been eradicated in Peru, claimed around 6,000 lives and caused illness among another 800,000. It spread from Peru to Columbia, Brazil, Chile, Guatemala. Berry describes it as ‘one of the major epidemics of the twentieth century’, and says precaution played a part in causing it.
It has since been discovered that the epidemic was, in part, a result of the Peruvian authorities’ decision to stop chlorinating drinking water supplies – and that one reason they stopped doing this was because reports issued by the American Environmental Protection Agency had claimed there was a link between drinking chlorinated water and an increased risk of cancer (a link which the EPA has since admitted is not ‘scientifically supportable’). ‘Chlorinated water would have prevented the outbreak’, says Berry. ‘The water production and cleaning system had gone wrong before the outbreak, so it wasn’t just that they stopped chlorinating water and then, bang, cholera arrived. But in a deteriorating situation, the failure to chlorinate – based on the principles of precaution and bad science – helped to make things a whole lot worse than they might have been.’
Berry points to the restrictions imposed on DDT – the pesticide used to get rid of malaria-carrying mosquitoes – as another example of how the ‘application of precaution’ can cause death and disease. In some third world countries where malaria had been all but eradicated over the past 20 years, there have been epidemics of the disease since DDT was restricted. Currently malaria is on the rise in all the tropical regions of the planet; in 2000, it killed more than one million and made 300million seriously ill. ‘Campaigners claimed that DDT was bad for the environment; they said that it caused harm to American birds of prey. I’m sorry, but why should people in the third world at risk from malaria care about American birds of prey? Decisions about these things should be based on local needs and on empirical evidence.’
The same should go for genetically modified crops, reckons Berry. ‘If we want to miss out on this new technology, that’s our lookout. But we should not be in a position to restrict the use of GM in the third world. As an African said recently, “You go ahead and ban GM crops, but can we eat first?”’ Berry says the restriction of the use of potentially life-saving technologies in the third world is ‘a kind of environmental imperialism – if something is perceived to be bad for some American bird, then no one else in the world can use it either. That is absurd; we really cannot go on like this.’
For Berry, issues of scientific and medical advancement, and the policymaking decisions that arise from them, should be based on two things – what people need, and good, rigorous data. ‘Almost no new technology can be assured to be risk-free. If your position is that you don’t accept any incremental risk, you are in effect saying no to all new technologies, whether it be a better anaesthetic, a better car, a better aeroplane, a safer environment for children – in fact anything worth having.’
Professor Sir Colin Berry is speaking at ‘Science, precaution and the future of innovation’, a debate organised by spiked and the Royal Institution at the EuroScience Open Forum in Stockholm on 26 August 2004. For more information visit the spiked-events page.
Science, risk and the price of precaution, by Sandy Starr
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