Living Columns & Blogs

GE crops study committee members offer their perspectives

Editor’s note: The Focus on Research column highlights different research projects and topics being explored at Penn State. Each column will feature the work of a different researcher from across all disciplines. The following is adapted from an article that originally appeared on The Conversation.

In a new report, the National Academies of Sciences, Engineering and Medicine have provided a broad review of available information on genetically engineered crops and their effects on the environment and human health.

The study, produced by a committee of 20 experts from diverse fields, found “no conclusive evidence of cause-and-effect relationships between GE crops and environmental problems,” such as reduced biodiversity in areas where GE crops are planted. Similarly, it found “no substantiated evidence” that foods from GE crops are less safe than foods from non-GE crops.

However, the report also concluded that although planting crops engineered to resist pests and/or herbicides generally has paid off economically for farmers, damaging levels of resistance have evolved in some targeted pests and weeds. And it found that regulations governing GE crops in some countries, including the United States, should be updated to reflect advances in genetic engineering.

Below are perspectives from two members of the study committee. Their comments underline a major theme of the report: discussions about GE crops need to move past broad pro/con statements and address the complexities of this fast-evolving field.

Leland Glenna, associate professor of rural sociology and science, technology and society, Penn State

There are several valuable insights in this report. It avoids making simplistic and authoritative pronouncements about GE crop technologies. People should avoid viewing GE crops as a single thing that is either beneficial or harmful.

Herbicide-resistant, insect-resistant and virus-resistant crops, for example, are three very different technologies and have had different social, economic and environmental effects. New and emerging technologies and applications, such as CRISPR-Cas9, add further nuance and complexity.

As a sociologist, I think the report’s most important finding is that the social and economic effects of GE crops will vary by the type of GE crop developed, the economic and environmental contexts of the farms that adopt them, and the social and economic contexts. For example, studies show that benefits to small-scale farmers in developing countries from planting Bt (insect-resistant) cotton have varied widely, depending on factors including seed prices, availability of credit and farmers’ access to markets.

It is important to avoid thinking about GE crop controversies as two groups of people pitted against each other — one group in favor, the other against — or that GE crops are either good or bad. Many perspectives are relevant, and GE crop technologies are complex and varied.

These technologies and applications are changing quickly, and I found myself hustling to comprehend those changes as a participant in this study. But I learned something more profound in the process. New knowledge emerges when people from different disciplines and subdisciplines exchange their research and expertise in an engaging and constructive way. The public presentations and public comments that the National Academy organized in connection with this report stimulated our research and discussions. As a result, the report represents something more than the sum of its parts.

I sincerely hope that this study expands the conversation beyond technological determinism and the tired, old, two-sides-to-every-argument approach to discussing GE crops. It is common for GE crops to be portrayed either as solutions to social and economic problems or as causes of them. GE crops are also commonly presented as though there were only two sides to this debate: Either you are for it or against it.

New technologies bring both promises and perils, and aspects that are promising to some people are perilous to others. The report makes it very clear that assessing the experiences of and prospects for GE crops is about more than merely evaluating technical risks. Legal, economic, social, cultural and individual factors are also relevant.

Michael Gallo, emeritus professor of environmental and occupational medicine, Rutgers University

As a toxicologist, my major concerns with respect to GE crops are effects on human and animal health. We reviewed about 400 to 500 studies, starting from before genetically modified organisms were commercialized. Our general conclusion was that the GE crops tested were no more harmful than non-GE versions.

Many of these studies evaluated animals through their lives and then did histopathology and clinical chemistry workups on most of the animals’ organs. In almost every case, the range of changes they found, in animals fed GE and non-GE foods, were within normal ranges. Studies done on pigs were especially interesting because pigs are physiologically similar to humans in many ways. Many studies have been done, but they have not found significant differences between pigs fed GE and non-GE foods.

We also reviewed numerous human health studies. For example, we looked for associations between GE crops and the incidence of various types of cancer by reviewing epidemiological studies that were conducted by the National Institutes of Health. There is no obvious correlation or association between cancer incidence and the introduction of GE crops in the United States.

To look for connections with digestive diseases, especially celiac — an immune reaction to eating gluten, a protein found in wheat, barley and rye — we consulted a large database at the Mayo Clinic. Celiac disease is on the rise in the United States, but again, we found no discernible connection with the introduction of GE foods. It’s also on the rise in the United Kingdom, where people do not typically eat GE foods.

We recommend more public funding for follow-up studies in areas where early studies produced ambiguous results. This is often an issue in studies where the sample sizes are relatively small. We need public support to develop better toxicological methods in general, for both GE and non-GE foods. Our approach should be that if a food is novel, you test it. That’s how Canada regulates food, and it’s the approach that this report recommends. Test the product, not the process that created it.

I would like to see this report move the discussion away from polemics. It’s a living document. People should look at the website and contribute their ideas. Let’s have a discussion about these issues.