We are not producing our food sustainably. Climate change is already reducing productivity in some areas, and this is projected to worsen. Agriculture is also responsible for a substantial share of climate-change gases, most unsustainable uses of fresh water, and is the main cause of the several hundred global “dead zones,” such as in the Gulf of Mexico and Chesapeake Bay.
Genetic engineering is often proposed as a major and necessary way to address these problems. But as developed so far, globally it has not contributed meaningfully to the changes we need.
Large corporations that dominate development of genetically modified crops have produced only a very few commercial successes — despite close to 30 years of effort. Over 99 percent of biotech crops are immune to herbicides, more commonly known as weedkillers, or control insect pests. That has led to hundreds of millions of pounds more of herbicide use, tens of millions of acres of herbicide resistant weeds, and a new generation of resistant crops that will greatly increase the use of older, riskier herbicides. Soil-preserving conservation tillage, sometimes attributed to genetic engineering, was largely adapted in the United States before herbicide-resistant crops, which have probably increased its adoption only modestly.
A strain of genetically modified corn that is insect resistant, known as Bt, has reduced insecticide volume, but some of these reductions are being reversed. Insects naturally immune to Bt are multiplying while others, formerly susceptible, adapt to tolerate Bt. And in many countries, including the United States, most grain seed is now treated with insecticides, even on crops containing Bt traits. Although used at lower volume than sprayed insecticides, seed treatments are implicated in the decline of honeybees. Increases in seed treatments despite Bt is, in part, because genetically modified crops have become part of, and have facilitated, our current unsustainable industrial agriculture system that aggravates pest problems.
As for food security, we produce enough food. Poverty and marginalization prevent access. Genetic engineering is used mainly in livestock feed crops and biofuel crops that are not useful to those who need more or more nutritious food. On the other hand, inexpensive ecologically based systems have been shown to improve production of food crops more, and more reliably, than is typically seen from the few available genetically engineered traits used by poor farmers.
That is why the largest international study on agriculture development and technology, the International Assessment of Agricultural Knowledge, Science, and Technology for Development concluded that genetically modified organisms should play a minor role in food security in developing nations. The project involved hundreds of scientists and had the support of the World Bank, several United Nations agencies, and many countries. Instead of genetic engineering, ecological farming (agroecology), better infrastructure (e.g. roads to markets, storage facilities, etc.), empowerment of women, and other approaches that are much more cost effective were emphasized.
Meanwhile, conventional plant breeding, including newer methods, continues to outperform genetic engineering in all regions, at much less cost per trait, but goes begging for funding at our universities. Molecular genetics research over the past 15 years shows that the potential of breeding is still largely untapped.
Moreover, there are no successful GMOs to reduce nitrogen pollution from fertilizers, which contribute to climate emissions and dead zones, while breeding has improved nitrogen use efficiency. Agroecology can reduce nitrogen pollution by 40 to 70 percent or more. Research has shown that these methods can reduce the need for fertilizers and pesticides by more than 90 percent, greatly reducing soil erosion and climate emissions, while maintaining or increasing productivity, resilience, and farmer income — even in developed countries like the United States. But as with breeding, the research and policies needed for these methods to be more widely adapted are neglected by the industry-driven agenda that focuses on GMOs. Similarly, conventional breeding to boost drought tolerance has seen substantial progress compared to the one commercial genetically modified trait designed for the same purpose, which has had minimal impact.
The GMO industry continues to emphasize unproven future applications of the technology. This can become a distraction — perhaps intentionally — from the overwhelming dominance of unsustainable uses. These dominant uses, such as the next generation of herbicide-resistant crops, will continue to prevail in the absence of major changes in policies, strengthening of regulations, labeling, and other needed changes.
Properly developed and regulated, some future engineered crops may add to sustainability. But we must also consider the opportunity costs of that approach at the expense of more effective, less costly, and more equitable farming methods.
Read the rest of this series on GMOs:
Doug Gurian-Sherman is a senior scientist in the food and environment programs at the Union of Concerned Scientists.