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Unit 13: Genetically Modified Organisms
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Rebecca J. Goldburg, PhD

Rebecca Goldburg is a Senior Scientist at Environmental Defense's New York City headquarters. Trained as an ecologist, Goldburg is active in public policy issues concerning food production, primarily ecological and food safety issues concerning aquaculture, antibiotic use in agriculture, and agricultural biotechnology.


What are your concerns with genetically engineered products?

Well, I think people have different motivations for being concerned, but certainly one of them is that genetic engineering gives scientists the ability to alter the food supply in ways heretofore that were not possible, and I think many consumers feel that they've had some bad experiences with the ways foods have been changed in the recent past, and they're concerned about the ability of genetic engineering to do things that might be unsafe or not to their liking for other reasons. I think there are also deeper ethical concerns that some people have, particularly when it comes to genetic engineering in animals.

How do you feel about the U.S. labeling requirements for GM foods?

There's essentially no labeling requirement for GM foods in this country. FDA requires labeling of foods under certain exceptional circumstances, but of the 50 or so GM foods that have been commercialized to date in the United States not one of them has required labeling.

Is part of problem not knowing what's in food?

I certainly think that most people are not comfortable with the notion that their food can be genetically engineered and they don't have the right to know about it and make choices based on changes that are made to their food. We're accustomed in this country to getting all sorts of information about our food. If you read the ingredients label on a package of processed food, it will list virtually all the ingredients in the food, many of them that will be unfamiliar to consumers, even to people like myself.

Nevertheless, there's something comforting about being able to choose for yourself what you want to put into your body, and unfortunately consumers aren't getting that ability with GM foods.

How much and where are the GE organisms in our foods?

The two major food crops that are heavily genetically engineered are corn and soybeans, and most of the corn that is grown in this country isn't for sweet corn, but rather for animal feed and processing. For example, corn syrup has become ubiquitous as a sweetener in our food supply, and much of that corn syrup is taken from generically engineered corn, as are all sorts of other products like cornmeal and cornstarch.

Soybeans are also a ubiquitous ingredient in foods, as a protein source and all sorts of ingredients. Most people when they buy crackers or cereal or some sort of soft drink may not focus on the corn or soybeans in the food. In fact, there's a good chance in any processed food you buy that either corn or soybeans or both will be an ingredient.

What are your concerns about GE foods?

When a food is genetically engineered, essentially what scientists do is they add a new gene to a plant or whatever organism is the source of the food. And genes code for proteins. In other words, the biochemical machinery of a cell in a crop plant, for example, will convert a gene to a protein so genetically engineering a crop plant is a bit like adding a protein to that crop plant, one that's been selected for addition for whatever reason.

And just like foods with other deliberately added substances, the addition of a new protein to a food can in some cases-probably a small minority of cases-but in some cases have undesirable consequences. In particular, all known food allergens are proteins, so every time a new protein is added to a food by genetic engineering there's a small but real chance that an allergen is being added to that food.

Unfortunately, food allergies aren't particularly well understood scientifically, so in many cases it's not possible to predict with any real degree of certainty whether or not a particular protein added to a food is an allergen or not. In most cases, proteins added to foods won't be, but to some degree we're playing roulette with American health, at least with food allergic people by adding a bunch of new proteins to the food supply without being really able to adequately screen them for their allergenicity.

Added to that is the fact that of course genetically engineered foods are not labeled. There are people with all sorts of food allergies in this country. In fact, just about any food you think of there's probably someone who's allergic to it, even things like zucchini or various spices. And the way people with food allergies deal with their allergy is to avoid the foods to which they know they're allergic.

But in the case of genetic engineering, because there's no labeling of genetically engineered foods, even if people do at some point begin to develop allergies to say genetically engineered soybeans, they're not going to be able to avoid them in their diet because they can't know what they're eating.

I think that's a very troubling future that we may see, where people have less control over their diets and can't quite figure out perhaps what's giving them unpleasant symptoms or reactions or even some cases causing life threatening reactions. Allergies in some cases can be deadly.

What are examples of genes added that have caused reactions?

There has been one crop developed to date that was demonstrated to cause allergy as a result of genetic engineering, and that was a soybean genetically engineered about a decade ago now to contain a Brazil nut gene. The goal of adding the Brazil nut gene was to actually make the soybean better poultry feed, but of course some of those soybeans would end up in human foods too.

And as it turned out, the protein that was added from Brazil nuts caused allergic reactions in Brazil nut allergic people, and a University of Nebraska scientist who looked at the soybean was able to document this phenomenon because he actually had in his laboratory freezer blood serum from people who were known to be allergic to Brazil nuts, and he was able to do some laboratory screens looking for what are called antibody-antigen reactions.

And this scientist's work was ultimately published in the New England Journal of Medicine, and it was the first time that a genetically engineered food was demonstrated actually to cause an allergy as a result of genetic engineering.

Now, after the research was published, the company that had been pursuing development of the soybeans, pioneer hybrid, made the very responsible decision not to commercialize the soybean, and that's to their credit. But the study does illustrate that the concerns about genetically engineered foods are real. They're not hypothetical. It is possible to add an allergen inadvertently to foods with genetic engineering.

What is the process for approval of GE foods?

The type of process a company will go through will depend on the product and what it's intended for. But if you just take an average food crop, where the plant is engineered for a reason other than to make it kill insects, that crop will be looked at by the U. S. of Dept. of Agriculture which is concerned about its potential effects on agriculture. Then the Food and Drug Administration asks that companies that voluntarily notify the agency before they put foods derived from that crop on the market.

So the regulation is much less than I think many people might imagine. For most genetically engineered food crops, there is no real environmental review. In other words, the crop doesn't have to meet a standard of environmental safety because it's overseen by the USDA, which isn't an environmental agency, and companies by law don't even have to bring genetically engineered foods to the Food and Drug Administration for approval before they go out in the market.

Now the biotech industry says that all companies should bring their foods voluntarily to the FDA before they market them and that may be true to date, although there's no way to really know for sure. But certainly if the biotechnology industry becomes much bigger in the future, with many more players, I don't think we can rely on voluntary notification as a way to protect public health.

What are some environmental concerns over BT corn?

There are a couple of reasons that BT corn has raised environmental concerns. One is a study several years ago that showed in the laboratory that pollen from BT corn was toxic to Monarch butterfly caterpillars, and some of the concerns over that matter have been resolved by new data, and in particular the one type of corn that is highly toxic to Monarch butterflies is being taken off the market.

However, there are still some outstanding issues that are somewhat technical, and some question marks about the long-term impacts of Bt corn on Monarch butterfly caterpillars.

Another big issue with Bt corn and other Bt crops is that widespread planting of these crops, which have Bt toxins in their tissue all the time, whether or not insects are feeding on a plant or causing economic damage to a crop is that the use of these crops will lead insects to evolve resistance to Bt toxins. Bt toxins have been used for decades in their sprayable form, a non-genetically engineered form where the bacteria themselves or forms of the bacteria themselves sprayed as natural insecticides-probably the safest class of insecticides we have.

Bt toxins are safe enough and are natural, and so even organic farmers use the sprayable forms of these toxins on crops. It's quite possible that there's a lot of concern among entomologists about the widespread plantings of genetically engineered Bt crops in far greater acreage than has ever been sprayed with Bt toxins, where the toxins are out there all the time in the environment, whether they're actually needed to control insects and whether they will lead pests to evolve resistance to these toxins. This would make not only the crops useless, but also potentially some of the traditional Bt sprays, which are very important to both conventional and organic fruit and vegetable growers.

Which is better, using Bt corn or spraying pesticides?

There are some circumstances in which Bt corn substitutes for insecticide use but in general the target pest of Bt corn, the European corn borer, is an insect that is rarely treated with insecticides. Farmers rarely treat their corn acreage with insecticide to prevent European corn borer infestation and the reason is that the European corn borer is an episodic pest. There are only outbreaks of European corn borer say roughly every five years on any particular farmer's field in the Midwestern corn-belt and so many farmers choose not to spray for European corn bores because on balance it just doesn't make sense economically.

For example, some data published from Iowa show that in the past something like only 2% of corn acreage has been sprayed with insecticide every year. So the effect of Bt corn on insecticide use is actually quite minimal, except in certain unusual situations.

Can you explain spontaneous hybridization?

Crops didn't just come into being. All crops come from wild plants that have been bred to be the modern crop plants we know today, and as such all crops somewhere in the world have related wild plants, with which in most cases they can interbreed. As a result, when a crop is genetically engineered to contain a new gene, a new trait, there's a reasonable chance, at least depending on where the crop is planted, that that crop can transfer via pollination its acquired trait to wild plants. That can be a real issue if the trait is one that confers an advantage to a wild plant and the wild plant is a weed, or potentially a weed.

For example one of the big weeds of cultivated rice is a different type of rice called red rice. So one might genetically engineer cultivated rice to tolerate applications of herbicides or weed killers. If you did that, probably within a couple years the red rice, which is the weed problem, would pick up the herbicide tolerance gene and the trait would be economically useless.

What are super weeds?

Another part of the notion of engineered crops causing what are sometimes termed "super weeds" is in certain circumstances crops may transfer a trait such as disease resistance that actually confers a new advantage to a weed that makes weeds able to thrive even more than they already do-makes them more abundant, makes them more of a management problem. That threat is conjectural at this point, but certainly is biologically entirely reasonable.

Is there evidence that the European corn borer may become resistant to Bt crops?

There isn't documented resistance at this point. But many of us worry that it's not a case of whether or not resistance occurs, but when.

Do all insects eventually develop resistance?

Insects that are routinely exposed to a particular Bt toxin will probably almost inevitably evolve resistance. Obviously, insects that just have incidental exposure may not.

What do you think of the EPA's resistance management plan?

I think it's still terrific that EPA has taken the initiative to go ahead and require resistance management of companies that are producing genetically engineered crops. It's really the first time that EPA has forced companies to have such stewardship of their products and their utility.

However, I have been disappointed in a number of ways about how the resistance management plans have been developed. My feeling is that the EPA has often let companies make the plans be too weak, and in some cases they are little more than public relations window dressing for what could be a very, very serious problem.

Does the EPA have the responsibility of monitoring seed usage?

Well, the EPA doesn't directly regulate farmers. The EPA is actually regulating the companies who sell the seed, and it's then the company's responsibility to get farmers to comply with resistance management requirements. So it's a bit complicated, and exactly how good is compliance among farmers? It's not entirely clear, although it seems to be much better in the case of Bt cotton than in the case of Bt corn.

Do the Insect management plans help forestall resistance?

In the case of BT corn, I certainly think the resistance management plans may help forestall resistance for at least some time. However, it's important to remember that the plans are basically built on some scientific experiments and a lot of mathematical modeling. They don't have a great foundation in practice. So they're all a big experiment and how well they work remains to be seen.

The EPA and the companies are well aware of this. Many of us in the environmental community argued early on that really there ought to be a little bit more science done before the crops were commercialized and the plants put into effect, but that didn't happen and we're now in the midst of a big experiment.

What is the current European attitude toward genetic modification?

Well, Europeans are certainly much more critical of GM technology and are certainly much more negative about GM food than Americans on average seem to be, although there's tremendous variety among American consumers.

But I think there are several reasons why Europeans are much more skeptical of GM foods. One is simply that Europeans on average take food much more seriously. They're much more interested in what they eat and its quality and so on then Americans on average-and that's a great 'on average.' I think Europeans also on average tend to feel more connected to the countryside.

In the United States, our food production is pretty industrialized. A lot of it occurs in the Midwest, out of sight and out of mind from where most Americans spend their time. In Europe, agricultural land is much more patchwork among places people go every day. After all, the countries are much smaller, many people still have family back in various towns or villages and so I think there's a sense among the populace at large of a somewhat greater connection to agriculture and how it's done and more concern about that.

Are Americans too lackadaisical as consumers?

Well, certainly I think it would be terrific if U.S. consumers became more concerned in general with how their food was produced, in part with GM technology and part with a lot of other things that are done in food production, for example, the heavy use of antibiotics in animal production, which is leading to some very hard to treat bacterial infections.

And while I'm certainly in no way against the use of modern technology in agriculture, I think it is really important to ask what are the risks of certain types of technology for consumer health, for the environment, and in some cases with animal production for effects on farm animals themselves. Unfortunately, all those sorts of concerns don't always get taken into account as people or producers get more and more interested in squeezing a lost penny of profit out of production and are able to externalize. In other words, to pass on to someone else-the public at large-the costs that are associated with new technologies.

What are the long-term effects of these products?

We really don't know what the long-term effects of most GM products are. My guess is that many of them are going to prove perfectly safe, but there's plenty of reason to think that some of them may not be and certainly if we begin to see more and more GM foods on the marketplace in greater variety, I'd bet that some of them are going to cause some problems.

What should be done then?

Well, I think there are a whole variety of steps that need to be taken. Some of them involve greater government oversight. For example, I think the Food & Drug Administration should have a mandatory approval system for genetically engineered foods rather than a voluntary notification system.

Some of the steps are to provide consumers with information so they can make their own choices and if things begin to go wrong, consumers have some tool to fend for themselves to make their own decisions. Companies in some cases can provide more information to consumers about what's in their food and how they're produced.

Do you think that biotechnology is good or bad?

It's probably wrong to characterize biotechnology as purely good or bad. It's really a collection of genetic techniques that can be used for all sorts of purposes for good and for bad.

That said, biotechnology, particularly in agriculture, is often promoted as a kind of panacea for all sorts of problems and I certainly don't think it's that, particularly genetic engineering.

Furthermore, I think there's often a sort of double standard for genetically engineered crops. On the one hand, proponents of these crops will talk about how they can be used to do all sorts of amazing things: to feed hungry people, to provide more nutritious foods, to end the use of pesticides, and so on and so forth, and of course they deserve to be patented too because they're so unique.

And then these very same individuals when they are asked about the risk to humans in the environment of biotech crops and biotech animals, too, will turn around and say, 'We've been genetically manipulating plants and animals for centuries for human benefit, and there's really nothing different about biotechnology, so you needn't worry your silly head about them. No new regulations or oversights are necessary.' And of course that's a complete double standard. You can't have it both ways, but sometimes it seems to me that some people are trying to do so.

What are the issues surrounding putting human genes into animals?

There are a lot of issues concerning the use of human genes in animals. There are some safety issues, particularly if genes are used that actually that have to come from human viruses. Those aren't human genes. But I think the primary issues are really ethical ones. Are we comfortable with an animal that is in essence part human? Would we eat such an animal?

Those are very tricky and uncomfortable questions for most people, and my sense is that most consumers at this point would rather not be seeing on supermarket shelves foods derived from plants or animals that contain human genes.

What is happening with GM fish?

Fish may be the first genetically engineered animals intended as food to reach the marketplace. There is one company now that has genetically engineered a very fast growing salmon that is trying to get approval from the Food & Drug Administration for commercial sale of these salmon. Unlike genetically engineered crop plants, genetically engineered animals do require approval from the Food & Drug Administration before commercial sale.

These salmon pose a number of very real ecological concerns. The majority of the salmon that people consume in this country at this point actually comes from salmon farms. They're not wild salmon. And there are some very serious environmental issues to do with the escape of farm salmon from salmon farms. In part these issues have to do with the fact that salmon escape in very large numbers from salmon farms, which are nothing really but nets in the water and contain huge numbers, hundreds of thousands of salmon, in a single net in a coastal estuary. On both the East and the West Coasts there are endangered runs of both Pacific and Atlantic salmon. For example, in Maine, escaped Atlantic salmon from salmon farms have already been identified by the Federal government as one of the main impediments to restoration of endangered runs of Atlantic salmon in Maine. And that's because the very huge numbers of escaped salmon breed with very small remaining numbers of wild Atlantic salmon, and the cultivated salmon are different genetically from the wild salmon, and so they essentially make the wild salmon more like stupid, fat, lazy farm salmon which isn't very good if the salmon are already in deep, deep trouble anyway and they're only a few hundred of them left.

So if you add genetic engineering to the mix, it just makes a bad situation potentially even worse that will have even more different farm salmon that when they escape can cause problems for the wild salmon.

What are some questions that we should be continuing to ask?

Well, I think there is a breadth of issues that consumers should be concerned about when it comes to genetically engineered food. One is clearly, is this food safe for me to eat, or safe for me to feed my children or to be in my infant's formula? Another issue is, what is the impact on the environment of this genetically engineered plant or animal?

Then there are broader issues, like "is this use of genetic engineering actually something that's making agriculture more environmentally sustainable or less sustainable? Is it exacerbating pesticide use or entrenching use of herbicides because it's a crop that's meant to encourage the use of herbicides? Is the crop going to encourage more vast monocultures of corn or soybeans?"

There are ethical issues too. For the most part, people haven't been too concerned about the ethics of genetically engineering crop plants, but when it comes to genetically engineering animals I think more people will have concerns. You know, after all, there's no People for the Ethical Treatment of Soybeans, but people feel a little bit differently about animals and the potential impact of genetic engineering on their health and well being.

Are GE crops affecting biodiversity?

Well, there are two ways in which genetically engineered crops can potentially affect biodiversity in a harmful way. One is that the crops themselves can cause some direct harm to plants or animals. For example, the potential effect of toxic pollen from BT corn on Monarch butterflies.

Another broader way is that the use of some of these crops may simply exacerbate current trends in the industrialization of agriculture towards the vast monocultures that encourage farming practices and a lack of biodiversity in agriculture that may ultimately be disastrous.


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