Safe Food: The Politics of Food Safety (33 page)

As evidence for the benefits produced by genetically engineered crops, the industry notes how quickly growers have adopted them. In theory, the crops should help growers. At the time farmers first began to plant transgenic crops, they were using more than 80 million pounds of conventional pesticides (a term that includes both insecticides and herbicides). Reducing the use of these chemicals should produce economic as well as health benefits, and a major argument for the value of transgenic crops is that they eliminate the need for hazardous pesticides—except Roundup, of course—by millions of pounds annually. This idea is central to the biotechnology industry’s public relations efforts. The advertisement shown in
figure 17
, for example, promotes the ecological advantages of transgenic crops. This advertisement, which much resembles those for the cigarette-selling Marlboro Man, is clearly meant to suggest that genetically engineered crops will save family farms.

As with all issues related to food biotechnology, its benefit to farmers is subject to debate. Also like the other issues, this one is complicated and lacks a firm research base on which to resolve outstanding questions. By 2001, most observers agreed that transgenic cotton required less use of pesticides than conventional cotton, but only in certain areas. In Arizona, for example, the use of transgenic cotton led to a breathtaking decline in the need for pesticides against budworms and bollworms: from 400,000 pounds in 1995 to just 2,000 pounds in 2000. In other states growing such cotton, however, the overall use of pesticides
increased
.
³¹
When it comes to corn and soybeans, however, the evidence is wide open to interpretation. Here are just a few observations: U.S. farmers who planted
Bt
corn in 1997 did much better economically than farmers who planted conventional corn, but in 1998 they did worse, largely because so much corn was produced that prices fell and the costs of seeds and pesticides increased. Transgenic crops—cotton as well as corn and soybeans—contributed to an overall decline in pesticide use of 2.5 million pounds from 1997, or just 1% of total pesticide use. Infestations with the European corn borer were relatively low that year, suggesting that fewer pesticides would have been applied anyway.
³²
In contrast, an analysis of data from 1999 found that Roundup Ready soybeans alone saved $216 million in the costs of controlling weeds and required 19 million fewer applications of herbicides. The contradictions in these results are due to the large number of variables that have to be considered in such analyses, many of them constantly changing, and some easier to measure than others.
³³
What seems most evident from attempts to evaluate benefits is that it is still too early to do so. We do not yet know the overall effects of transgenic crops on cost, productivity, and use of pesticides.

FIGURE 17
. In 2001, the biotechnology industry’s public relations campaign featured the equivalent of the Marlboro Man. Rather than cigarettes, however, this advertisement promotes the industry’s view of the ecological advantages of transgenic crops (reduced pesticide use, soil conservation), and consequent benefits to society (farm preservation). In 2002, a series of elegant photographs promoted the benefits of genetically modified corn, soybeans, cotton, and papaya.

Indeed, one of the chief complaints of environmentalists is that transgenic crops will
increase
the use of agricultural chemicals, especially of Monsanto’s Roundup. Farmers planted Roundup Ready soybeans on just 1 million acres in 1996 but on 48 million acres in 2001; they applied Roundup to 20% of farm acres in 1995 but to 62% in 1999.
³⁴
Roundup generates billions of dollars in annual sales, and Monsanto benefits twice; it sells the herbicide
and
the seeds for the crops that resist it. The company’s studies show that Roundup Ready soybeans survive when doused with the chemical, and are as nutritious when fed to rats as conventional soybeans.
³⁵
Whether the use of Roundup is environmentally beneficial is, of course, a debatable issue. Monsanto points out that it registered Roundup as an herbicide in 1974 with minimal subsequent evidence of hazard: “Consumers benefit from Roundup Ready soybeans because farmers can control weeds better . . . with less herbicide while using a herbicide with the best environmental profile.” To bolster that argument, the company cites two lines of research: Roundup binds so tightly to soil particles that the chemical does not harm nearby vegetation (and, therefore, is unlikely to move to groundwater), and it decomposes naturally to benign substances.
³⁶

Critics, however, raise alarms about the heavy use of this product: Roundup may induce weeds to develop resistance; it may poison fish, earthworms, or other beneficial creatures; and it may disrupt soil ecology. From a biochemical standpoint, resistance to Roundup is not difficult to achieve. Its active chemical, glyphosate, inhibits the action of an enzyme that helps make three amino acids needed to construct plant proteins. Plants cannot make proteins when this enzyme is blocked. Bacteria,
however, are well known to produce a mutant variant of this enzyme that is completely unaffected by glyphosate; they do so through “point” mutations (mutations that alter just one amino acid) or mutations that cause the enzyme to be produced in such large amounts that glyphosate becomes ineffective. Such mutations could occur in plants as well as in bacteria. The transfer of Roundup resistance to weeds through pollination also is probable, and has already occurred. The idea of widespread resistance to Roundup is not improbable, and it alarms the industry as well as environmentalists.
³⁷

The most highly critical statements about the use, toxicity, and persistence in soil of Roundup can be traced to an exhaustive scientific review published in 1995. The review identifies toxic effects from the chemical itself as well as from ingredients used in its formulation. It describes studies on experimental animals in which Roundup caused eye and skin irritation, cardiac depression, gastrointestinal distress, reduced weight gain, increased frequency of tumors, and reduced sperm counts. In people, Roundup appears as the most common cause of pesticide-related illness among landscape workers and the third most common cause of such illness among agricultural workers. Roundup residues persist in vegetables a year after treatment and in soil for more than a year. Researchers report that Roundup produces toxic effects on beneficial insects, fish, birds, and earthworms; eliminates vegetation used as food and shelter for animals and birds; and reduces the activity of bacteria that fix nitrogen and perform other “friendly” tasks.
³⁸
Whether these effects are worse than those produced by the pesticides replaced by Roundup is a question that demands further research. In the absence of convincing studies, such decisions are a matter of opinion.

Underlying questions about the potential risks of transgenic plantings are more general concerns about what Roundup Ready and
Bt
crops might do to biodiversity. The huge amount of U.S. farmland devoted to transgenic crops borders on
monoculture
—the planting of one variety of a crop to the exclusion of all others. The lack of biological diversity means that any point of vulnerability leaves monocultured crops open to overwhelming attack by insects, weeds, or diseases—and to catastrophic losses. Such vulnerability is illustrated by the splitting of stems of Roundup Ready soybeans when grown in hot climates. When this happened, observers guessed that crop losses could reach 40%. They wondered if the biochemical changes that induce resistance to glyphosate might also cause plants to produce a form of cellulose (lignin) that becomes brittle in hot temperatures typical of southern states and tropical countries.
³⁹

From such examples, it should be evident that questions about the relative risks and relative benefits of genetically modified foods cannot be answered without further research and experience. As I explain in
chapter 7
, the industry and its sympathetic government regulators decided in advance—using a strictly science-based approach to risk assessment—that the foods were safe and that few precautions were necessary, and they assumed that any unanticipated consequences of transgenic foods could be handled appropriately by existing regulations. As it turned out, unexpected consequences revealed the inadequacies of this approach. Some examples follow.

Critics of food biotechnology insist that without prior experience, transgenic foods raise safety issues that are difficult to define, predict, or quantify but that nevertheless should be taken seriously and evaluated in advance—
before
the foods are grown extensively and enter the food supply. They invoke the precautionary principle (discussed in the introduction). As support for the need for precaution, they cite the examples to which we now turn. These examples explain why safety issues—especially those that cannot easily be resolved by scientific studies—become matters of politics. A precautionary approach threatens the economics of the entire agricultural biotechnology enterprise.

The classic case of the unanticipated consequences of nutritional—if not food—biotechnology concerns supplements of the amino acid tryptophan. Like all amino acids, tryptophan is a component of proteins in all organisms. Supplements of tryptophan have been used for years as self-medication for insomnia and neurological conditions. In the 1980s, companies began to genetically engineer bacteria to produce larger amounts of tryptophan so that this amino acid would be easier to collect and purify. In 1989, tryptophan supplements produced by a Japanese petrochemical company, Showa Denko, caused eosinophilia-myalgia syndrome (EMS), an unusual constellation of symptoms of muscle pain, weakness, and increased blood levels of white cells (eosinophils). Eventually, more than 1,500 people who had taken the supplements became ill, and about 40 died. The FDA prevented further marketing of the supplement, and the company stopped making it.
⁴⁰

This example might just indicate that genetic techniques sometimes lead to unexpected problems, but this particular situation had additional implications. Because tryptophan is a normal component of body proteins, investigators did not think that the genetic engineering processes were at fault. Instead, they suspected that a toxic substance emerged during the manufacturing process, and they attempted to identify it. Victims, however, sued Showa Denko for about $2 billion, thereby introducing liability as an intervening factor. The company not only refused to cooperate with FDA investigations but also tried to discredit the scientists who had linked the syndrome to its product. Showa Denko demanded prepublication copies of the studies under the Freedom of Information Act (most scientists would find this intimidating as well as a nuisance) and used a carefully selected advisory committee to argue that the studies were done poorly and could not be reproduced.

Furthermore, the company sponsored its own research studies, organized a conference to announce the results, and paid for publication of the conference papers as a supplement to the
Journal of Rheumatology
. Not unexpectedly, the sponsored researchers raised questions and produced data that appeared to exonerate Showa Denko. In contrast, the one independent paper (“prepared by US Government employees and entirely funded by the US Government”) concluded that the Showa Denko tryptophan supplement caused the EMS epidemic. The government scientists charged that the studies sponsored by Showa Denko were

based on supposition, surmise, and conjecture. [They] direct attention toward potential biases or confounding events with a low probability of having occurred and a still lower probability of having had a substantial effect on the studies reviewed. In so doing, they direct the reader’s attention away from the combined weight of evidence of the studies, which strongly supports a causal association of Showa Denko LT [tryptophan] and epidemic EMS.
⁴¹

To date, the toxic component remains “incompletely characterized,” making it difficult to institute preventive measures. In this case, the company’s self-interested stance not only interfered with finding the cause of the disease but also failed to resolve lingering uncertainties about the safety of the genetic engineering processes used in manufacturing the supplements.

Next we turn to the possibility that genetic engineering might cause
foods
to produce toxic substances, in this case, lectins. Lectins are proteins in
plants that are naturally toxic to insects and nematode worms. They do not bother us because we cook lectin-rich foods—kidney beans, for example—long enough to unravel the structure of the proteins and destroy their function. In 1998, an investigator in Scotland announced that rats became ill when they ate transgenic lectins, thereby initiating a political furor of quite astonishing proportions.