When Food Kills

Abstract

The safety of food is possibly the oldest human preoccupation. In early prehistoric times, the need to communicate where the next meal might come from and whether it was safe to eat must have produced a strong selection pressure in favour of language acquisition. The hunter-gatherers were also learning to control fire, a hazardous technology that, among other benefits, allowed meat to be cooked and lessened the risk of consuming live parasites. So it is little wonder that in modern times so much of what we hear, what we say, and what we read centres on the same areas of concern, nor that we get our fingers burned occasionally as the food industry invents new technologies for every generation. This is a long and very rich history. Hugh Pennington, who chaired an inquiry into the 1996 Escherichia coli outbreak in Scotland, makes a clear case that these episodes are not simply the result of late twentieth century technology. In When Food Kills1 he provides a broad and well illustrated sweep of the disasters that have struck the industry in recent and not so recent times. To give an example, he records how between 1912 and 1937, some 65 000 people died of bovine tuberculosis in England and Wales through drinking cow's milk. His writing style is unusual for such an exercise—a pleasing blend of the scientific and the journalistic. What we are offered is a front-line report with the insights of a microbiologist and an admixture of personal opinion that takes the book far beyond simple documentary. Pennington deals not only with medical aspects such as molecular biology, genetics, and epidemiology, but also with the historical and sociological implications of food disasters, their impact on the status of science and the public's faith in it, and the ways that all of these fit in with disasters of other types. A theme running through the book concerns the ‘Lardner effect’—Pennington's term for the phenomenon whereby a rare disaster affecting large numbers of people at once has a much greater impact on public anxiety than an endemic background risk that in total affects a far greater number. This applies not only to foodborne infections that rarely kill, such as Campylobacter, but also to more deadly pathogens; the incidents that worry people most are those with a large number of simultaneous victims, such as acute epidemics of infection, or oil rig disasters, or motorway accidents. Nonetheless, Pennington's analysis did remind me of the opposite scenario described by Carl Sagan in his book Pale Blue Dot.2 Sagan reckoned that, when frequency is related to likely death rate, we are at greater risk of dying from asteroid impact than from a commercial plane accident; yet few of us spend much time worrying about asteroids. Perhaps the Lardner effect is overcome, and denial supervenes, when the possible devastation becomes massive. This may have happened in the 1990s when projected estimates of the scale of nvCJD cases ranged from a few dozen to several million. The most pessimistic estimates, fortunately now deemed unlikely, were simply too awful to contemplate. In his preface Pennington claims that, through a long tradition connecting Macbeth with Joseph Lister, Scotland has taken a central part in the history of foodborne disasters. In the most recent past he refers to the E. coli epidemic at Wishaw and to the emergence of nvCJD at higher incidence in Scotland and the North of England than elsewhere in the UK. Major figures in prion research before the advent of bovine spongiform encephalopathy (BSE) included the Edinburgh workers Alan Dickinson, Richard Kimberlin, and Hugh Fraser. Pennington's ‘Scotland bias’ is not intended to be taken too seriously, but for the record, at least two important individuals based north of the border do not get a mention in the book. One of these is David Doyle, a Glasgow neuropathologist who was active in the early response to the emergence of BSE. The other was a dietitian, Julie Phillips, without whose knowledge of the propensity for offal to find its way into the human food chain, based on her deep Scottish roots, an early comment might not have influenced the debate at a key stage.3 It is of course the contributions these individuals made, and not their origins, that make them noteworthy. When Food Kills stands out from other accounts of the subject by providing a rich perspective that includes disasters unrelated to the food industry. I am not sure whether enduring lessons can be learnt from the linking themes, but the book deserves attention from anyone who appreciates the combined attributes of a practising microbiologist, a scientific authority and a broadly read thinker. That should be all of us.