On October 27, Nobel Laureate Sir Richard Roberts delivered a lecture to the Northeastern University community, making “The Case for GMOs,” or genetically modified organisms.
“If anything, GMOs are safer than traditional plants,” said Roberts, a Distinguished University Professor in Northeastern’s College of Science, as he addressed about 100 students and faculty at Curry Student Center. “We need more science in politics and less politics in science.”
Genetically modified crops have been a subject of debate since at least 1994, when the Food and Drug Administration (FDA) approved the Flavr Savr tomato, the first genetically-modified (GM)crop, for human consumption.
The harvesting of genetically modified plants has increased significantly in the years since. Last year, more than 53.7 million hectares of GM corn were produced worldwide, representing one-third of all land planted for corn in 2015. Genetically modified soybean crops have also increased exponentially – over 92 million hectares were planted in 2015, more than 80 percent of the total soybean plants harvested.
The U.S. has been one of the main players in commercializing genetically modified crops, and GM ingredients have inevitably made their way onto grocery store shelves. However, public concerns over risks to the environment and human health remain.
The U.S. National Academy of Sciences (NAS) published in 2015 the results of a multi-year comprehensive assessment of the safety, efficacy, and future of GM crops. The committee compared GM crops with their conventionally grown counterparts and found that “no differences have been found that implicate a higher risk to human health safety.”
The committee also examined the environmental effects of GM crops. One concern is that new genes will spread to wild populations and interfere with natural ecosystem processes. However, the NAS report stated, “although gene flow has occurred, no examples have demonstrated an adverse environmental effect of gene flow from a GE crop to a wild, related plant species.”
Another worry is that use of GM crops will decrease biodiversity across species. The committee found that use of the Bt toxin, which is used as a biological pesticide to deter insects from attacking GM plants, did not have a negative effect, and in some cases actually contributed to increased biodiversity.
“The committee found no evidence of cause-and-effect relationships between GE crops and environmental problems,” the report said, adding that, “the complex nature of assessing long-term environmental changes often made it difficult to reach definitive conclusions.”
A dishonest campaign
Greenpeace and other environmental groups, however, have seized on those uncertainties, exaggerating the potential threat. They continue to argue that GM foods pose a risk to human health and to the environment, and that such foods should either be banned or carry labels that warn consumers. Responding to pressure from environmental activists, more than half the countries in the European Union ban the planting of GM crops, though most still import GM feed for livestock.
Roberts says Greenpeace and its allies have vastly overstated the dangers of GMOs, and by doing so, they have significantly slowed scientific progress in the field of biotechnology. This progress has become all the more important as the global climate has continued to change in rapid and unexpected ways.
“[GM crops] are essential for the future of agriculture,” Roberts said in an interview. “It will become increasingly difficult to grow the crops we know and like. Climate change is not going to make it easier to grow crops.”
Earlier this year, Roberts organized a campaign calling on Greenpeace to be honest with the public about the safety and benefits of GM crops. So far, 121 Nobel Laureates and more than 6,000 scientists and citizens have signed an open letter to Greenpeace that essentially asks them to “stop scaring people,” as Roberts puts it.
“There’s just no doubt about whether the method is inherently safe or not,” Roberts said. “There’s nothing unnatural.”
Making crops more climate resilient
Climate change contributes to uncertain weather conditions, problems with water supply, and, in some cases, an influx of invasive species that can damage crops. GM crops are a potential way to protect against these risks.
Climate change will probably exacerbate water-supply issues for rainfed and irrigated farmland,” the 2015 report said. “Some regions will become drier and others wetter, with increasing unpredictability of precipitation and seasons and more frequent extreme weather events.”
By conferring traits for heat or drought tolerance to traditional crops, genetic modification could increase resilience to rising temperatures and changing precipitation rates. Genetic engineering is one of many approaches to make agriculture more resilient to climate change impacts. However, scientists like Northeastern University’s Roberts believe that genetic modification will be essential if countries do not reduce carbon emissions soon.
“Part of the problem with climate change is it’s a very slow process,” Roberts says. “It’s not something you’re going to witness immediately. It’s probably something that’s going to affect your grandchildren.”
Those effects will be felt the most in developing countries, where a loss of crop yield due to drought could devastate the population.
“In sub-Saharan Africa, drought is going to be a major problem,” Roberts says. “Once you know which genes can help mitigate something, then you can move these genes into the crops you want to grow.”
According to a recent article from Wired, Tanzania is beginning to develop GM crops despite a government that has previously opposed the technology. The government’s position has softened now that the region is facing a water shortage that will affect millions of people this year.
“It’s this convergence of local GM solutions coming online at a time when climate change impacts are really starting to be felt on a daily basis that has tilted the balance of power away from the luxury of caution and toward the urgency of feeding not 9 billion people by 2050, but millions of people now,” reported Wired.
Have yield benefits been oversold?
Despite the likely benefits in addressing the risks of climate change, other benefits related to overall yield may not live up to the longstanding claims advanced by the biotech industry.
In an October article for The New York Times, investigative reporter Danny Hakim concluded that while GM crop use has increased over time in the United States and Canada, this has not had a significant impact on yield, despite the fact that increased yield is thought to be one of the major benefits of GM crops. While the long-term yield trend for both corn and rapeseed has gone up in both the U.S. and Canada, it has increased similarly in Western Europe where planting of the crops is banned, suggesting that the increase in yield is not a result of GM technology argued Hakim. The increase in yield for sugar beets in Western Europe actually exceeded that of the U.S., despite the widespread introduction of GM crops in the U.S. circa 2007. Hakim also argued that using GM crops has not notably reduced the use of pesticides.
In sum, companies with a major stake in GMOs, like Monsanto, have promised a larger yield and reduced pesticide use without actually making their claims a reality.
“With the world’s population expected to reach nearly 10 billion by 2050, Monsanto has long held out its products as a way ‘to help meet the food demands of these added billions,’ as it said in a 1995 statement,” Hakim noted. “That remains an industry mantra… But a broad yield advantage has not emerged.”
The lack of significant yield increase was addressed in the 2015 National Academies’ report, but the committee also emphasized that traits like drought and pest resistance might offer a greater advantage over traditional crops in a world of rising temperatures and extreme weather events.
“There is a need to consider trait performance not just from the perspective of maximization of efficiency or yield but from the perspective of robustness – that is, minimizing the risk of total failure in an uncertain and extreme climate,” concluded the 2015 National Academies report.