Safe Food: The Politics of Food Safety (28 page)

As complaints about the disparity between the promises and the realities of food biotechnology became more strident, companies began to put more resources into projects that might benefit the developing world. Monsanto’s scientists, for example, are genetically engineering oilseeds to contain beta-carotene, a precursor of vitamin A. This vitamin is especially lacking in undernourished populations, and its addition to the diet produces an almost miraculous range of health improvements.
¹⁴
Development
of such products is time-consuming and expensive, and success is uncertain. Companies introduced genetically engineered papaya in Hawaii, for example, to replenish an entire industry ravaged by viral disease. The fruit grew well in the first seasons, but its developers remain cautious about its long-term viability: “We’d all be nuts to say that this is the final solution. . . . Biological systems evolve.”
¹⁵
This comment reflects yet another reality; it is one thing to develop a food in a laboratory but quite another to grow it successfully under field conditions. A 1994 statement by one business analyst still applies: “Nearly 20 years into the gene-splicing revolution . . . no one has cured cancer or produced a bioengineered miracle of loaves and fishes for a hungry third world. The industry is still peddling dreams.”
¹⁶

Such doubts enrage industry supporters in the United States and, sometimes, in developing countries. Florence Wambugu, for example, is a plant pathologist from Kenya who has worked with Monsanto since 1992 to develop a genetically modified sweet potato that can survive infection from a virus that otherwise would greatly reduce crop yields. At the Tufts University conference I attended in 2001, she predicted that the bioengineered potato would increase worldwide sweet potato production by at least 15%, increase the income of farmers by $41 million, and improve the food security of 1 million people—without any increase in the costs of production. Ms. Wambugu is an eloquent and forceful promoter of biotechnology as the solution to worldwide food shortages, and she does not mince words about the harm caused by “antibiotech lobbies”:

Antibiotechnology protesters . . . deny developing countries like my home, Kenya, the resources to develop a technology that can help alleviate hunger, malnutrition and poverty. . . . As an African, I know that biotech is not a panacea. It cannot solve problems of inept or corrupt governments, underfunded research, unsound agricultural policy, or a lack of capital . . . but as a scientist, I also know that biotech is a powerful new tool that can help address some of the agricultural problems that plague Africa. The protesters have fanned the flames of mistrust of genetically modified foods through a campaign of misinformation. These people and organizations have become adept at playing on the media’s appetite for controversy to draw attention to their cause. But the real victim in this controversy is the truth. . . . I know of what I speak, because I grew up barefoot and hungry.
¹⁷

In 2001, her sweet potato was in field trials, and the level of its productivity or acceptance would not be known for some time. Nevertheless, Monsanto has used the potato in its public relations campaigns since 1996 (“the sweet potato project will ultimately be a major contribution
to food security for some of the poorest farmers in the world”), and the Biotechnology Information Council, which runs an industry-sponsored public relations campaign, also uses her work: “Florence Wambugu helped develop sweet potato varieties that are resistant to a complex set of viruses that can wipe out three-fourths of Kenyan farmers’ harvest. . . . Similar techniques are being used to improve other staple crops of the developing world, including cassava, banana, and potato.”
¹⁸
These statements are promises. The crops are not yet in production, but the public relations materials do not emphasize that point.

The most highly publicized example of the gap between promises and reality is “Golden Rice,” genetically engineered to contain beta-carotene, a precursor of vitamin A. Although this rice also is not yet in production, it has been the industry’s primary advertising tool to promote the humanitarian benefits of food biotechnology (see
figure 12
). This rice raises a variety of issues that illustrate some further points about the interweaving of science and politics in food biotechnology, as we will now see

Much of the promise of food biotechnology depends on its science, but the realities depend on social as well as scientific factors. Nowhere is this distinction better illustrated than in the case of Golden Rice. To understand why the interplay between the scientific and societal issues makes genetically modified foods so
political
, we need to begin with an explanation of the extraordinary scientific achievement involved in creating Golden Rice.

Scientists who are puzzled by public distrust of food biotechnology tend to see its techniques as extensions of those of traditional plant genetics but superior because they are more efficient and precise. Traditional plant breeding can be tedious. Suppose, for example, that you would like to create a tomato with a thicker skin so it can be transported without getting crushed. Using the typical genetic methods, you would grow many kinds of tomatoes and look for a rare plant that produces tomatoes with thicker skins. You might also treat tomato embryos with chemicals or radiation to induce mutations; if you are lucky, a mutation will lead to fruit with a thicker skin. You then grow seeds from these tomatoes into plants, select progeny plants with thicker skins, cross them (through pollination) with tomato plants with other desirable traits, and, eventually, end up with thick-skinned tomatoes that breed true. A process like this involves luck as well as skill, takes an average of six to eight years of growing cycles, and can (and often does) result in a tasteless supermarket tomato. Other such manipulations created the full array of fruits, vegetables, and crops that make our food supply so abundant. It is safe to say that virtually all plants that constitute part of today’s food supply were genetically manipulated in one way or another. Traditional genetic manipulations permit the transfer of genes only between members of the same species or those that are closely related—apples and pears, for example. In contrast, agricultural biotechnology extends these techniques to address problems of efficiency, time, and species limits on transferable traits.

FIGURE 12
. This advertisement for the benefits of Golden Rice is part of an industry public relations campaign to promote public acceptance of genetically modified foods; it appeared frequently in 2001 in publications such as the
New Yorker, Scientific American
, and the
New York Times
. The text fails to emphasize that the rice, which “could help alleviate more suffering and illness than any single medicine,” is not yet available.

Because both traditional plant genetics and biotechnology involve similar manipulations and because they both achieve the same result—insertion of new segments of DNA into a plant’s existing DNA—biotechnologists maintain that the plants they develop are no different from those produced in old-fashioned ways, and should not be viewed or treated differently by regulatory agencies or the public. As we will see (and as the appendix explains in further detail), the steps involved in creating a transgenic plant are numerous and complex, and they introduce DNA segments that may come from unrelated organisms. Do these differences matter? The response is
no
if one focuses on the similarities: DNA is DNA no matter where it comes from. The response is
yes
if one focuses on differences or the societal implications of the technology. Points of view govern such responses and lead to political controversy.

Plant bioengineering is accomplished through
recombinant
DNA technology, through which the DNA segments that comprise a desirable gene from bacteria, for example, are inserted (recombined) permanently into the DNA of an entirely different organism—in this case, a plant. Scientists using recombinant techniques have created insect- and herbicide-resistant crops by taking genes from bacteria and transferring them to corn and soybeans. To develop Golden Rice, they recombined genes and DNA regulatory segments from daffodils, peas, viruses, and bacteria to induce rice to make beta-carotene in its endosperm—the white, starchy part of the grain. Rice, like all grains, consists of three principal parts: a surrounding sheath of nutrient-rich bran, an inner endosperm containing starch and a little protein, and an embryo, which draws on the energy and nutrients in the grain when it begins to grow into a plant (see
figure 13
). Rice makes small amounts of beta-carotene in its bran layers, but not in the endosperm. Most people just eat the endosperm, however, because millers remove the bran layers when they convert brown rice to white rice (which is why white rice in the United States is enriched with several vitamins and iron).

FIGURE 13
. The metabolic steps through which plants make beta-carotene from precursor molecules, and animals convert beta-carotene to vitamin A. An enzyme carries out each step. Rice bran contains information for the complete set of enzymes to make beta-carotene, but some enzymes are inactive in the endosperm. To create Golden Rice, scientists obtain genes (DNA) for the missing enzymes from other plants and bacteria and insert them into the DNA of rice (see
tables 12
and
16
,
pages 158
and
280
).

Rice bran and highly pigmented fruits and vegetables (such as melons or carrots) make beta-carotene in a series of steps in which precursor molecules are converted to beta-carotene by specific enzymes (which are proteins), one for each step. Rice endosperm lacks three of the required enzymes. To insert beta-carotene, researchers Ingo Potrykus and Peter Beyer and their colleagues in Switzerland and Germany obtained genes for the missing enzymes from daffodils and bacteria. They also isolated genes or regulatory DNA segments from peas, viruses, and other bacteria to help the recombinant enzymes function in rice endosperm. After a decade of effort during the 1990s, the techniques worked. The scientists made rice that contained beta-carotene and identified it immediately by its yellow color (hence: Golden Rice). They published this work in 2000.
Figure 13
illustrates the pathway of biosynthesis of beta-carotene and the enzymes replaced by genetic engineering. The pathway illustrates an important distinction: beta-carotene is not the same as vitamin A but is a
precursor
of the actual vitamin. We (and other mammals) have enzymes that convert beta-carotene to vitamin A in our bodies.
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The technical challenges involved in moving genes from one organism to another—daffodils and bacteria to rice, for example—are daunting, even to experts. Scientists must find the genes for the missing enzymes, reproduce them, and make them function. The “make function” part is particularly challenging. Genes do not work independently. They have to be
regulated
, which means in this case that the rice needs to be “told” when, where, and for how long the genes for making beta-carotene should do so. Scientists must also find, duplicate, and transfer the genes or DNA segments for these regulatory functions into the rice along with the genes for the missing enzymes. Accomplishing these tasks is a technical
tour de force
—an art as well as a science—not least because of the extraordinary number of genes and factors required, each requiring its own separate bioengineering step carried out in just the right order. As an illustration of the complexity of this work,
table 17
in the appendix (
page 302
) summarizes the
less
complicated of the two approaches used to insert beta-carotene genes into rice.

Complicated as they are, the genetic engineering steps are only the
first
part of realizing the humanitarian benefits of Golden Rice. The inserted genes must be transmitted to seeds; the rice must continue to make beta-carotene when taken out of the laboratory and grown in fields; people must accept, buy, and eat the rice; and the beta-carotene must be absorbed, split into vitamin A, and function in the human body.
Table 12
lists these requirements in greater detail. These additional tasks also can be difficult to accomplish. One production problem, for example, is the relative instability of transgenic plants with multiple inserted genes; such plants tend to lose the transgenic traits over several generations. Another is that the scientists engineered beta-carotene into a variety of rice that grows best in temperate zones. To succeed in developing countries, the technology must be transferred to locally grown varieties.