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8 March 2004 Killer food and disaster scienceT. Hugh Pennington When Food Kills: BSE, E.coli and Disaster Science Oxford University Press, 2003 (256 pp). ISBN 0-19852-517-6 (hard cover) RRP $82.95. Each year, about one third of us suffer from food poisoning (OzFoodNet 2002). For most of us, it is inconvenient but not life threatening. It can be very serious, however. The 1996 E. coli O157 outbreak in Scotland affected about 300 people and fourteen died (Pennington, 2003, pp. 1–24). Hugh Pennington, professor of bacteriology at Aberdeen University, chaired the inquiry into that incident. Starting with that case study, his important new book examines general problems of food safety before making links with other risks in modern society, ranging from the Challenger space shuttle explosion to football crowd disasters. Those responsible for public safety will learn important lessons from Pennington’s book. It also raises broader questions of understanding and managing risk in the modern world.
The specific case study is chastening. Almost all the infections were traced to one shop. Though seen as such a model of good practice it was voted ‘Scottish Butcher of the Year’, the shop breached several basic rules. The same knives, scales and cutting surfaces were used for both raw meat and cooked products. Staff didn’t wash their hands before moving between cooked meat products and raw meat. The hand basins didn’t have soap or drying facilities. Instead of being cleaned with a bactericide after use, surfaces were washed with a biodegradable detergent. Bacteria were transferred from raw beef to cooked meat products by ‘unwashed hands, uncleaned knives and contaminated working surfaces’ (p. 42). The unsafe practices had been followed for years without any comment after regular visits from food inspectors. So what went wrong, and what lessons could be learned about the general issue of food safety? Pennington’s inquiry found the inspections were too brief and superficial to identify unsafe practices. Inquiries into other disasters make exactly the same point: inspectors are often relatively junior, inexperienced, poorly trained and subject to influence or ‘capture’ by those they are inspecting. As Pennington concludes, ‘this raises a serious question about the utility of traditional inspections’ (p. 65). In the food poisoning outbreak, it took time to identify the source of contamination. For several days, the meat products that had made people sick were still being bought and eaten. Other food safety problems have much longer time scales and consequently much more devastating impacts. The classic example is the emergence of variant Creutzfeldt-Jakob disease among people who had eaten beef from cattle affected by bovine spongiform encephalopathy (BSE), commonly known as ‘mad cow disease’. In that case, the fatal illness emerged several years after people ate the beef. Further, because it was a new medical condition, it took some time to establish the link between cause and effect. When the connection between beef and the condition was established, it sparked a wave of concern about the safety of foodstuffs. The transmission to humans of ‘mad cow disease’ also caused some reflection on the broader issue of the risks of modern life. Pennington (pp. 211–13) says that unusual events like these and the attack on the World Trade Centre have produced a belief that life has become more hazardous. This is partly poor history. The death toll from the 2001 attack does not compare with past military actions like the bombing of Hiroshima or Dresden, with natural disasters such as severe earthquakes or massive volcanic eruptions, or with such disease outbreaks as the bubonic plague in medieval Europe. The perception is also a result of an effect Lardner (1859) noted a long time ago: one event that kills twenty people has much more impact than twenty events that each kill one person, even though the overall result is the same. The Bali bombing had a devastating impact because it killed nearly 100 Australians, most of them young people. Every three weeks on Australian roads about 100 people die, most of them young people, but this is so predictable we call it ‘the road toll’, as if it were the inevitable price of using the road. The attack on the World Trade Centre was appalling, but the number of American citizens who died was about the number killed in that country each month on the roads, or every two weeks by guns; neither the road deaths nor the consequences of gun ownership provoke much political reaction.
The BSE case made people think science is out of control and posing new hazards. While there is reason to be concerned about the possible effects of genetic engineering, Pennington argues that the science to protect us from many health risks is well known but not rigorously applied. In the case of the E. coli outbreak, the inspection system failed to enforce the precautions set by legal standards based on science. There are good examples of science being used to reduce risk. Analysis of road accidents showed the benefits of seat belts, so they were made compulsory. The accident risk increases when drivers are drunk, so we now have breath tests. The changes aroused some opposition, but are now accepted. They have reduced the number killed each year on Australian roads from about 3000 to about 1700. The change that would now do most to reduce road deaths would be a ban on young male drivers, but this is politically unlikely. Another avoidable hazard arises from allowing heavy vehicles to share the road with small cars. There is little discussion of the huge public subsidy of road freight, despite the deaths and injuries that result. Urban road users are encouraged to buy four-wheel drive vehicles by a tax concession, dating from the time when they were mainly used on farms. Now many people feel it is no longer safe to be on the road in a small car, given the number of large four-wheel drive vehicles out there. So an arms race is going on, increasing the average weight of vehicles and making them more hazardous to pedestrians, cyclists and other vehicles. Rather than tackle the social issues of young male drivers or heavy vehicles, decision makers opt for expensive engineering solutions, like wider roads. This raises a more general question of the interaction between science and policy. When science showed that releasing chlorofluorocarbons (CFCs) would deplete the ozone layer (Molina & Rowland 1974), the company responsible argued that this was only a scientific theory (Dotto & Schiff 1979). Politicians took no action until the mid-1980s when depletion of the ozone layer was actually measured. Even then, it took another decade to refine the agreement and tackle the problem effectively. Twenty years of inaction made the problem much worse. There is a similar issue with global climate change. Fifteen years ago, many scientists were convinced that human use of fossil fuels was at least partly responsible for climate change (Lowe 1989). It took until 1996 to develop the Kyoto protocol, an agreement to curb emissions of carbon dioxide from industrialised countries. This timid first step, effectively stabilising emissions at the 1996 level, was justified by the growing scientific confidence that fuel use is a discernible cause. The science says we need to reduce emissions to about one-third of the present level (Inter-governmental Panel on Climate Change 2002). The Kyoto protocol is still being opposed by politicians who claim that it would cost too much, and by a new group of opponents who say the agreement does not solve the problem of climate change (Lomborg 2001). While few governments are as irresponsible on this question as the Howard administration, their studied inaction on climate change is consistent with the gloomy view expressed by historian Paul Kennedy (1993). He said politicians are unlikely to take decisive action now in the interest of future generations, as long as they can argue that experts are divided and more research is needed. This poses for scientists the difficult task of being clear about the science without over-stating its certainty or over-simplifying the complexity of natural systems.
The guide should be the precautionary principle: where the consequences could be serious or irreversible, lack of complete scientific certainty should not be a reason to postpone cost-effective preventive measures. While there remain grounds for debate about what constitutes a ‘cost-effective’ response, climate change clearly poses the risk of serious or irreversible consequences, so we should respond. We are more threatened by ignorance or by failure to apply existing knowledge than by advancing science. We need to develop new understandings that reflect the complexity of natural systems. The support for ‘sustainability science’ recognises that we need to move beyond the narrow knowledge of single disciplines to understand the complex interactions in the natural world (Kates et al. 2001). It has been wisely said that we can never change only one thing in a complex system. Change always has costs as well as benefits, losers as well as winners. The task of decision-makers is to recognise that complexity and ensure that the costs are truly worth the benefits. So they need credible and robust scientific advice from qualified and independent sources. The systematic erosion of our capacity for independent science is a serious obstacle to informed decisions. It will always be difficult for unqualified decision-makers to decide between qualified experts who reach different conclusions. This is a common problem because there are often different legitimate interpretations of a complex and uncertain situation. So we need within the public service the expertise to evaluate complex technical arguments. The modern doctrine of content-free management leads to uninformed decisions. This does not just threaten the safety of our food, but has produced a systemic incapacity to respond to complex environmental issues. We are now technically able to produce serious and effectively irreversible changes to the natural world (Steffen et al. 2004). Our inability to make wise policy decisions about that technical capacity directly threatens the survival of civilisation. REFERENCESDotto L. & Schiff H. I. 1978, The Ozone War, Doubleday, New York. Inter-governmental Panel on Climate Change 2002, Third Assessment Report, Earthscan, London. Kates, R. W., Clark, W. C., Corell, R., Hall, J. M., Jaeger, C. C., Lowe, I., McCarthy, J., Schellnhuber, H. J., Bolin, B., Dickson, N. M., Faucheux, S., Gallopin, G. C., Grubler, A., Huntley, B., Jager, J., Jodha, N. S., Kasperson, R. E., Mabogunje, A., Matson, P., Mooney, H., Moore III, B., O’Riordan, T., & Svedin, U. 2001, ‘Sustainability Science’, Science, 292, pp. 641–642. Kennedy P. 1993, Preparing for the Twenty-First Century, Harper-Collins, London. Lardner D. (ed.) 1859, The Museum of Science and Art, Walton and Maberly, London, cited in Hugh Pennington, 2003, When Food Kills. Lomborg B. 2001, The Skeptical Environmentalist, Cambridge University Press, Cambridge. Lowe I. 1989, Living in the Greenhouse, Scribe, Newham. Molina M. J. & Rowland F. S. 1974, ‘Stratospheric sink for chlorofluoromethanes: Chlorine catalysed destruction of ozone’, Nature, 249, 810–814. OzFoodNet 2002, Foodborne disease in Australia: incidence, notifications and outbreaks, Annual report of the OzFoodNet network, Canberra. [Online], Available: http://www.cda.gov.au/pubs/cdi/2003/cdi2702/htm/cdi2702g.htm [2004, Feb. 19]. Steffen, W., Sanderson, A., Tyson, P., Jäger, J., Matson, P. Moore III, B., Oldfield, F., Richardson, K., Schellnhuber, H-J., Turner II, B. L. & Wasson R. 2004, Global Change and the Earth System: A Planet Under Pressure, Springer-Verlag, Berlin. Ian Lowe is emeritus professor of science, technology and society at Griffith University. He has received many awards for his contributions to science and public debate. He is currently a member of the Environmental Health Council and the Radiation Health and Safety Advisory Council, among others. |
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