GMOs? Not So Fast GMOs were developed to satisfy certain values, so it is reasonable to judge them by those values—and others

Genetically Modified Organisms (GMOs) have become a hot political issue. Thirty states have considered legislation that would label food containing GMOs. Two states, Maine and Connecticut, have passed GMO labeling laws that will go into effect if nearby states pass GMO labeling laws. Vermont’s GMO labeling law will go into effect in 2016—barring the success of a lawsuit against it. Outside of the United States, 64 countries have GMO labeling laws. However, U.S. Rep. Mike Pompeo (R-Kan.) and Rep G.K. Butterfield (D-N.C.) have introduced a bill in Congress that would block states from implementing their own labeling laws. Critics have lampooned the bill as the “Deny Americans the Right-to-Know” or DARK Act.

What is the fuss about? Are foods containing GMOs something that consumers should be worried about? Are they the product of unnatural tampering—are they “Frankenfoods”? Many scientists say “No.” Rather, they say that proponents of labeling are anti-science. The debate has become polarized.

As a philosopher of science, I think I can best help by sorting through some of the arguments concerning GMOs—arguments being a philosopher’s stock-in-trade—in particular by showing how a proper understanding of science and values can help to understand the issues at stake. This is difficult to do, since some of the GMO studies themselves are controversial. So, I will try to be scrupulous with my sources, citing only peer-reviewed articles and well-accepted findings.

Let me put my cards on the table from the outset. I think there are good reasons to label GMOs. However, I am not “anti-GMO”—I don’t think GMOs should be banned or outlawed, and some applications are promising. Research should continue. But there needs to be stricter oversight of GMO testing. In short, I take a middle-ground position which will no doubt antagonize both sides. But it is the middle ground that the arguments steer us toward.


Roberta Millstein, professor of philosophy at University of California, Davis

Roberta Millstein, professor of philosophy at University of California, Davis

What are GMOs?

GMOs are organisms, including plants and animals that we eat, that are created using recombinant DNA methods (“genetic engineering”). These methods allow a gene from any species, including distantly related species, to be inserted and subsequently expressed in a different species, such as a food crop. (When a gene is “expressed,” that means that it is producing a desired protein, which it will do if it is in the right genetic environment and the right external environment). There are also GMOs that are not designed to be eaten, such as GM bacteria for medical purposes.

Most GMOs on the market today have been designed in one of two ways. First, many crops are resistant to herbicides. For example, Monsanto’s “Roundup Ready” crops are resistant to Monsanto’s Roundup herbicide, which has glyphosate as its main ingredient. These crops allow farmers to spray their crops with the herbicide, killing the weeds but not killing the crop. Second, many crops contain a pesticide, usually Bt (Bacillus thuringiensis), which protects crops from pests such as the European corn borer. Here the pest eats the crop and dies; there is no need to spray.

Biotech companies claim that modifications like these will increase crop yields, save farmers time and money, and reduce the use of pesticides and herbicides.

The majority of GM plants are used to make ingredients that are used in other foods: soybean, canola, sugar beets, corn, cotton. These are contained in everyday foods such as cornstarch in soups and sauces; corn syrup as a general purpose sweetener; cottonseed oil, canola oil, and soybean oil in mayonnaise, salad dressings, cereals, breads, and snack foods. GMOs are also fed to livestock, leading to indirect human consumption of GMOs.

According to the FDA, in 2012, approximately 88 percent of corn, 93 percent of soybeans, and 94 percent of cotton produced in the United States was genetically modified. This suggests that unless you have made a special effort to avoid eating GMOs, you have almost certainly eaten them.

Other modifications of foods on the market include vitamin A enriched rice, virus-resistant papayas, and virus-resistant squash. Some modifications that have been proposed or are under research, but are not yet on the market, include apples and potatoes that resist browning (recently approved by the FDA), salmon that grow twice as fast as their un-engineered counterparts, and oranges that resist citrus greening disease.


The labeling question and the anti-science charge

Currently, labeling foods containing GMOs is purely voluntary. The Non-GMO Project coordinates an effort to label foods that do not contain GMOs. Also, foods that are labeled “organic” do not contain GMOs. The FDA supports voluntary labeling only, not mandatory labeling.

GMO critics say that voluntary labeling is not enough. Some say that GMOs may contain toxins or allergens. They point out that GMOs are in so many foods that it is almost impossible to avoid them. They want mandatory labels so that people can more easily decide for themselves if they want to eat food that contains GMOs.

GMO proponents, on the other hand, say that GMOs have been proven safe, so labels are unneeded—and unscientific.

It is a mistake to lump together climate change deniers, evolution deniers, and GMO critics, in part because the reasons for doubt in each case are different and in part because the so-called “precautionary principle” would incline us to accept climate change while rejecting GMOs, but also because (ironically) a proper understanding of evolution forms the basis for some of the concerns about GMOs.

For example, the American Association for the Advancement of Science (AAAS) states that “crop improvement by the modern molecular techniques of biotechnology is safe” and that labels are “meant to alarm.” The Genetic Literacy Project’s Jon Entine cautions against the anti-science views of anti-GMO NGOs. A well-cited poll by the PEW Research Center shows that the views of scientists and non-scientists diverge on a number of issues, including GMOs, climate change, evolution, among other topics; in a typical response, a Slate article casts this as a bipartisan anti-science problem. A recent cover of National Geographic calls it a “War on Science.”

It is true that some GMO critics go too far. Calling GMOs “Frankenfood” is simply a scare tactic; that genetically engineered food is “unnatural” is neither here nor there. Not all that is unnatural is unsafe (think life-saving drugs) and not all that is natural is safe (think naturally occurring poisons).

But is it really anti-science to raise any concerns about GMOs?

In short, no. It is a mistake to lump together climate change deniers, evolution deniers, and GMO critics, in part because the reasons for doubt in each case are different and in part because the so-called “precautionary principle” would incline us to accept climate change while rejecting GMOs, but also because (ironically) a proper understanding of evolution forms the basis for some of the concerns about GMOs. More specifically, I have identified six problems with the claim that GMO critics are anti-science.


Problem 1: The anti-science charge falsely assumes that science is value free

Many philosophers have argued that values may be an intrinsic part of all sciences; value-free science might be a myth.

What are values? Values are things that are important to us. They can include moral values, political values, or aesthetic values.

Climate science is a clear-cut example of a value-laden science. We study the connection between fossil fuels and our changing climate because we value the benefits of using fossil fuels as energy but are concerned about harms to humans and other species. Another example of a value-laden science is medical science, which includes values such as improving health and well-being.

When people criticize a science, they are not necessarily criticizing theory, data, or inferences drawn from data—they might instead be criticizing values that are embedded in the scientific theory or practice itself.


Problem 2: The anti-science charge falsely assumes that GMO science is value free

The stated and unstated reasons for developing GMOs in the first place were all value-laden: making money for biotech corporations and their shareholders, feeding the hungry, developing new and beneficial strains of food for consumers, reducing pesticide and herbicide use to save money and help the environment.

In other words, the production of GMOs is not pure science for the sake of knowledge alone. It is not “value-free” science. It is not even close.

Furthermore, GMO critics are not challenging the truth of genetic engineering technology or genetics, as some challenge the truth of climate change or evolution. At best, they might challenge the truth of studies that purport to show the safety of GMOs and evaluate risks. But note that studies that concern health and risk are value-laden—and individuals might reasonably differ on how they weigh risks.

Because GMOs were developed specifically in order to satisfy certain values means that it is reasonable for them be judged by those values—and other values.


Problem 3: The anti-science charge fails to recognize that questions about rights involve questions about values.

The question over whether to label GMOs is a question about the public’s right to know what they are eating and the right to decide what they eat, in accordance with their values. GMO science involves values, but it does not and cannot tell us what our rights are. The question of what our rights are is a question about values that falls outside of the domain of GMO science. Thus, to take a stand for labeling GMOs on the basis of rights is not anti-science.

Triclosan, an antibacterial agent used in some toothpastes and hand sanitizers, can serve as an analogy. There is some preliminary evidence that it is a hormone disrupter. For now, however, the FDA says that triclosan “is not currently known to be hazardous to humans.” In the meantime, it is labeled. Consumers can decide whether to use those products.

However, some anti-labelers insist that the very labeling of GMOs as GMOs implies that there is something wrong with GMOs, akin to warning labels on cigarettes or alcohol. Similarly, they maintain, ingredient labels are there to inform those who may be allergic to or otherwise harmed by one of the ingredients.  Thus, anti-labelers might think that proponents of labeling GMOs are anti-science because label proponents refuse to accept the evidence that shows that GMOs are safe. I will return to the issue of GMO safety momentarily.


Problem 4: There really is something biologically new about GMOs

GMO proponents claim that there is nothing new about GMOs because farmers have been genetically modifying food for centuries. And this is true to a certain extent. Artificial selection led to the domestication of many species, with significant modifications. More recent techniques include hybridization of inbred lines.

These statements are correct, but they are misleading. The techniques of genetic engineering are different from selection or hybridization. These techniques allow genes from one species to be introduced into a very distantly related species—for example, the insertion of a gene from a fish into a tomato (created but never commercialized) or the insertion of a gene from a pig into an orange (currently under research).

These kinds of modifications have an “ick” factor, but we should avoid knee-jerk reactions; that is not the real problem. The worry of using distantly related genes—resulting in changes of a larger magnitude than would be likely to occur in nature or by most other methods—is how they will behave in a very different genetic context given that genes can affect the expression of other genes in unpredictable ways.


Problem 5: We lack good evidence for GMO safety

The evidence for the safety of GMOs is not as good as some GMO proponents claim because the scientific protocols are somewhat lax. In the United States, the testing of most GMOs is voluntary, not mandatory; according to the FDA, most GMOs are “generally recognized as safe” (GRAS). The AMA, however, has called for mandatory safety testing. Currently, testing is performed by the companies who manufacture the GMOs without FDA oversight. The studies are for the most part short term (three months), meaning that the long-term effects of consuming various GMOs are simply unknown.

These are reasonable—and scientifically-based—concerns about the studies that have been performed to date.  There is enough uncertainty about the studies of GMOs to make it reasonable for individuals to want to decide for themselves whether to eat GMOs or not.

Compare the many steps involved in the FDA’s testing protocols for new drugs. Most notably, after performing FDA-reviewed laboratory and animal tests, the company performs a series of clinical trials in humans in three phases, which the FDA monitors, to test if the drug is effective and safe. Next, the company sends its data from all these tests to FDA’s Center for Drug Evaluation and Research (CDER). A team of CDER physicians, statisticians, toxicologists, pharmacologists, chemists and other scientists review the data and proposed labeling. After a drug is approved for the market, the FDA continues to monitor its performance. A more cautious, scientifically based approach would include FDA oversight for testing of new GMOs; the protocols would not necessarily need to be identical to those for new drugs, but they could be (and arguably should be) stronger than they are.

Jon Entine trumpets a study by A. L. Van Eenennaam and A. E. Young in an article entitled, “The Debate About GMO Safety Is Over, Thanks To A New Trillion-Meal Study.” But let us take a closer look at the nitty-gritty details of Van Eenennaam and Young’s article, which seeks to provide a review of studies on livestock that have been fed GMOs, as well as field data on livestock that have been fed GMOs.

In the former category, Van Eenennaam and Young particularly highlight two “long-term” studies (which they define as studies between 90 days and two years in duration), one performed on 36 dairy cattle and one performed on 40 pigs, both seeking to determine the health effects of consuming Bt corn on the study animals. The authors note that there have been other “long-term” peer-reviewed multigenerational studies (less than 100 of them), but point out that these two studies “were notable in that they included appropriate controls consuming isogenic non-GE lines of corn, and both comprehensively examined a range of phenotypes and indicators of growth and health.” Although Van Eenennaam and Young clearly state that they do not think that further such studies are needed, they seem to be implying that the other “long-term” multigenerational studies either do not contain the appropriate controls or are not as comprehensive (or both). And yet even the “notable” studies are cautious in their conclusions, for example acknowledging that “[e]xposure to GM maize did induce some alterations in localized and peripheral immune responses in weanling pigs which require further investigation”; another article states that “further studies are currently underway to evaluate the lifetime health and growth performance of offspring from Bt MON810 maize-fed sows.” In other words, the researchers themselves do not think that their studies are the last word on the health effects of Bt corn on pigs, and they call for further study.

In the latter category are data from the animal industry; it is here that the vast majority of the “trillion meals” referred to in Entine’s article can be found. These data, unlike the two “notable” studies, are not data from controlled experiments, and thus, we should have much less confidence in their findings. In a controlled study, every effort is made to reduce the differences between groups to just the cause under study, e.g., by using similar-as-possible animals randomly assigned to one of two groups, with one group fed Bt corn and one group fed the genetically identical corn lacking the Bt modification. When a study is not controlled, other factors may be producing the effect in question; as Van Eenennaam and Young themselves note (while dismissing the significance), there have been changes in the genetics of the animals and in management practices during the period that the data cover, and there may have been other changes as well. Furthermore, the animal industry data include factors like feed to gain efficiency, data which are important for farmers but not the point at issue for consumers who are interested in the safety of their food.

A scientific attitude is a cautious attitude that does not draw conclusions that go beyond the data or denigrate those who expect the usual scientific standards be followed. Entine fails to display that scientific attitude. Two “notable” controlled animal studies with small sample sizes plus uncontrolled data from the animal industry (regardless of the numbers of animals or period of time that the data cover) are not enough to conclude that GMOs are safe for humans to eat. Researchers from the controlled studies themselves think that further study is warranted; tougher standards exist and are used for testing drugs (and by the way, even the FDA does not declare drugs that pass its stringent standards to be “safe”). If we think that certain studies should not be done for ethical reasons, then by all means, let us not do them, but then let us not confuse our hesitancy to subject humans and animals to extensive testing with evidence for the safety of what we are declining to test for.

People who say flatly that “GMOs are safe” are being unscientific in another way. A GMO is not a GMO is not a GMO. Each one needs to be tested; the safety of one does not show the safety of another, given that each genetic combination is different. For example, the safety of including Bt pesticide in corn is potentially quite different from including vitamin A in rice. And the safety of Roundup resistance in one plant is not necessarily the same as in another (since gene expression is affected by other genes).


Problem 6: Saying GMOs are safe overlooks environmental concerns

This is arguably the most serious of the six problems. There are several categories of actual and possible environmental harms.

One is the evolution of herbicide-resistant and pesticide-resistant plants and animals 
(in other words, evolution of organisms no longer killed by herbicides like Roundup). 
This effect was predicted, although Monsanto denied that it would occur. It was known that weeds naturally varied in their response to Roundup (glyphosate): 
with some very susceptible and others less so (i.e., some were resistant). Spraying Roundup on the weeds killed the susceptible ones, in effect selecting for the resistant ones and allowing them to flourish without competition.

In 2012, the Weed Science Society of America (WSSA) website listed 22 Roundup-resistant weed species in the United States. Dow AgroSciences estimates that 100 million acres in the United States are already impacted by Roundup-resistant weeds; Dow has used this estimate to argue for the deregulation of 2,4-D corn.

2,4-D is considered a more toxic herbicide, with a heightened risk of birth defects, more severe impacts on aquatic ecosystems, and more damage to nearby crops and plants.

But why should we expect a different outcome this time? Where does the cycle of herbicide application leading to the evolution of herbicide resistance end?

Another environmental harm is that the evolution of Roundup-resistant crops has lead to an increased use of herbicides (not the promised decrease). According to Charles Benbrook, the Roundup-resistant weed phenotypes are forcing farmers to increase herbicide application rates, make multiple applications of herbicides, and apply additional herbicide active ingredients. Note that the World Health Organization has recently classified glyphosate as “probably carcinogenic to humans.”

On the other hand, Bt corn has led to a reduction in pesticide use so far. However, western corn rootworms have now evolved Bt resistance, as have other corn pests. So, that decrease may be short-lived, or as with Roundup, stronger pesticides may be proposed.

Yet another possible environmental harm is the transmission of genes (outcrossing or gene flow) from GMOs to wild weedy relatives. When GMOs reproduce with closely related wild species, transfer of herbicide-resistance to weeds can occur.

This creates the same problem as the evolution of herbicide resistance—herbicide-resistant weeds—but with a different cause. Susceptible species include rapeseed (canola), sugar beets, and corn. Roundup Ready wheat (not on the market yet) was found to be six times more likely than non-GMO control lines to produce outcrossed offspring.

Relatedly, there can be transmission of genes from GMOs to other, conventional (non-GMO or organic) crops. In a 2014 survey of 268 organic and non-GMO farmers in the United States, 31 percent said that they had found or suspected GMO presence in their crops. Of these, 52 percent said that they had been rejected by a buyer because of it.

In Oaxaca, Mexico, one of the places where diverse strains of maize (corn) are found, researchers found “a high level of gene flow from industrially produced maize towards populations of progenitor landraces.” This is concerning because these maize strains might otherwise be used to create new commercial corn varieties.

Finally, there are possible effects on other species that consume the GM crops. As with humans, there is no widely accepted evidence of direct harms yet (there is laboratory evidence that Bt corn harms Monarch butterflies, but no field evidence).

However, there is some evidence of indirect harms. Increased spraying of Roundup has led to a loss of milkweed habitat for Monarch butterflies and contributed to a major decline in the size of their populations. Much Roundup Ready corn seed is coated with neonicotinoid pesticides; neonicotinoids have been shown to affect bee reproduction (whose pollination we rely on) and to persist and accumulate in the soil.

In sum, these concerns over environmental harms—concerns about evolution or transmission of pesticide resistance to weedy relatives, concerns about increased pesticide use, concerns about unwanted contamination of crops, and concerns over harms to other species—do not reflect a misunderstanding or rejection of “science.” On the contrary, they reflect an understanding of the relationships between different species and the sorts of evolutionary changes that can occur.  If someone is concerned about these environmental effects, they might want to avoid consuming GMOs on those grounds alone.

Summarizing the six problems described above: given the role of values in the deployment of GMOs, given the lack of mandatory and long-term testing of GMOs with outside oversight, and given the demonstrated environmental harms, it is not anti-science to want to GMOs labelled as GMOs.


Other important values in the GMO debate

Monsanto claims that we need GMOs to feed the world, a commendable, value-laden goal.

Critics point out that as pesticide use has increased with GMOs while pesticide resistance among weedy and pest species has also increased, crop yields have been harmed. To combat the resistance problem, crops have been designed that contain multiple modifications (stacked-trait crops). However, a study commissioned by the USDA showed interactions between the introduced genes often reduced yield, and researchers were “surprised” not to find greater yields among the studied GM crops more generally (although they did find that GM crops were more stable over time). Another study by the USDA showed that in the United States 31 percent (133 billion pounds) of the 430 billion pounds of the available food supply in 2010 went uneaten. Here again, however, it is worth emphasizing that not all GMOs are the same, so that some may do better than conventional crops under some conditions while some may do worse than conventional crops under different conditions.

There are other methods for improving crop yields, such as the System of Rice (Root) Intensification method or by making better use of the “available diversity of eminently adapted alternatives.” Perhaps more importantly, as Hugh Lacey suggests, we should put the same resources toward alternatives to GMOs as we have put toward GMOs themselves in order to truly know which methods are best.

The effects on farmers are another value-laden consideration, in part tied to crop yield. That is, if it turns out that GMOs increase crops yields, that ought to be good for farmers, but not if they are reduced. Other considerations are that farmers cannot save or trade GMO seeds, or they will face lawsuits. Seeds from GMOs tend to be more expensive than non-GMO seeds, and sometimes require buying the related pesticide (e.g., Roundup for Roundup Ready crops). More dramatically, there have been 250,000 farmer suicides in India, which some have blamed on the failure of Bt cotton to live up to its promises and subsequent farmer debt.

GMO proponents have sought to debunk some of the concerns I’ve mentioned in this section by pointing out that they result from faulty use of GMO technology by farmers. Some say that farmers failed to follow Monsanto’s recommendation that “refuges”—areas without GMO crops—be planted. This allows non-resistant pests a place to flourish where they can interbreed with, and thus dilute the numbers of, resistant pests. This may be 5 to 20 percent of total land, depending on the GMO.

Others suggest that farmers in India likewise were similarly to blame for poor results. For example, Guillaume Gruèrea and Debdatta Sengupta claim that farmers lacked information about growing conditions, pesticide use, the importance of planting proper seeds, and the earnings to be expected from using this technology. However, these same authors also admit the possibility “that under the conditions in which it was introduced, Bt cotton, an expensive technology that has been poorly explained, often misused and initially available in only a few varieties, might have played a role in the overall indebtedness of certain farmers in some of the suicide-prone areas of these two states, particularly in its initial years” (emphasis added). They suggest that there is a “critical need to distinguish the effect of Bt cotton as a technology from the context in which it was introduced” (emphasis added).

I disagree. Context matters.

In discussing the values embedded in the use of GM crops, we must evaluate conditions as they in fact are. It might be the case that in some more perfect world, with different biotech companies using different practices, different GMOs, and different farmers, the problems I have talked about here would not have occurred. Perhaps, then, there is nothing wrong with GMO technology itself, only GMO practices. But so what? We do not live in that more perfect world. Technology is never deployed in a context-free situation. Imagine evaluating the efficacy of a traffic light without considering the context in which it is deployed—traffic patterns, traffic volumes, and traffic speeds. The result would be meaningless. The same is true for GMOs. We have to evaluate technologies in their context.


Final thoughts

In truth it is hard to know how to weigh the varying values involved in the use of GMO crops, and there is still much that we do not know. Surely GMO research should continue, although with better testing protocols before the seeds are deployed. We should proceed more slowly and carefully. It might turn out that some GMOs are ones that are truly beneficial (e.g., by saving a species that cannot be saved any other way) with few or no downsides.

But here is what we do know.

If someone wants to follow their values and avoid GMOs, they have no way to do so. GMOs contain new proteins as compared to conventional crops, and any new protein could potentially be an allergen or toxin when consumed over time. It is almost impossible to avoid eating GMOs; most Americans are eating GMOs and foods made with GMOs without knowing what they are eating. There is little to no oversight of the production of GMOs in the United States; scientific protocols fall far short of what they could be. Thus, while there is no strong evidence that GMOs are harmful to humans, the tests have been inadequate. Environmental harms, on the other hand, have occurred and are well-documented; here it is important to remember that the majority of GMOs on the market today are resistant to particular herbicides or contain a pesticide, and that we should evaluate particular GMOs in particular contexts, not abstract GMOs in abstract contexts.

People who would like to avoid GMOs, whether out of concerns for potential health harms or concerns over actual environmental harms, are not being allowed to judge the risks and make choices for themselves and their families. For these reasons—so that people can follow their reasonably held values—we ought to label GMOs as GMOs.

Acknowledgements: Thanks to Dan Hicks for helpful comments, and to Matt Brown for the opportunity to present the ideas in this article to the Center for Values in Medicine, Science and Technology at the University of Texas at Dallas.