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My latest Mind and Matter column at the Wall
Street Journal is about the precautionary principle as exemplified
by the German e coli outbreak, which has now killed 29. Less
precaution about new technology might have meant fewer deaths:
A technology that might have prevented contaminated produce from
infecting thousands of Germans with E. coli was vetoed-by
Germany-11 years ago for use in the European Union. Irradiating
food with high-voltage electrons is a process that can kill
bacteria on or in solid objects, just as pasteurization can kill
them in liquid foods.
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John S. Dykes
When the European Commission proposed in 2000 that irradiation
be allowed for a greater range of foods and at a higher dose, the
German government vetoed the measure. In the U.S., food irradiation
is used for various products, including ground beef, but most
retailers resist the practice, lest the word "irradiated'' on the
label scare off customers.
In Europe, irradiation is used only for some spices and herbs.
The German veto was a perfect example of what is wrong with the
"precautionary principle"-the idea, long advocated by
environmentalists, that the burden of proof is on innovators to
demonstrate that a new technology is safe before it is
The food-irradiation industry has argued strenuously for decades
that its technology is proven to be safe, cannot leave food
radioactive and does not taint the taste of food. Yet even in the
U.S., legislation requires that irradiation be shown not just to
have net benefits but to do no harm at all-no diminution of vitamin
content, for example.
As Michael Osterholm, director of the Center for Infectious
Disease Research and Policy at the University of Minnesota, pointed
out in an interview, that is a standard to which microwave ovens,
grills and even medical products such as vaccines and hip
replacements cannot aspire. The technology is effectively judged
guilty until proven innocent.
The precautionary principle often holds new technologies to a
higher standard than existing technologies. In Europe, for example,
genetically modified foods must be labeled in such a way that they
can be traced "from farm to fork." Organic crops grown with manure
have no such requirement placed on them, but these products pose
higher risks to human health than genetically modified crops.
Manure is quite safe if properly composted to a sterilizing
temperature, but that cannot always be achieved.
A lot of concerns over the use of irradiation are out of date.
In the past, cobalt-60, a gamma-emitting radioactive isotope, was
used as a source of the radiation for food, which tainted the whole
enterprise with scare words like "gamma" and "radioactive." Now,
however, the most common means of food irradiation is to use an
electron gun of the kind found, until the arrival of flat screens,
in every ordinary TV set.
Dr. Osterholm reckons that irradiation is the necessary fourth
pillar of a public-health platform-the other three pillars being
chlorination, vaccination and pasteurization-that has delivered
astonishing progress against infectious disease and a dramatically
longer average life span over the past century. Since it's
impossible to make food entirely clean by using plastic sheeting in
the field or by washing, irradiation could be the last, best step
before any inherently unsafe food reaches our plates.
Of course, nobody can be certain that irradiation, if it had
been common practice by now, would have prevented the E. coli
outbreak in Germany, though the process certainly does kill that
particular kind of bacterium. But that is the point. We do not
know. We can never know what deaths would have been prevented if a
technology had been allowed that, in fact, was not allowed.