A popular weapon used by those critical of agricultural biotechnology is to claim that there has been little to no evaluation of the safety of GM crops and there is no scientific consensus on this issue. Those claims are simply not true.
NOTE: This piece was co-written with a writer at the Genetic Literacy Project, JoAnna Wendel.
“The science just hasn’t been done.”
– Charles Benbrook, organic researcher, Washington State University.
“There is no credible evidence that GMO foods are safe to eat.”
– David Schubert, Salk Institute of Biological Studies
“[The] research [on GMOs] is scant…. Whether they’re killing us slowly— contributing to long-term, chronic maladies—remains anyone’s guess.”
– Tom Philpott, Mother Jones
“Genetically modified (GM) foods should be a concern for those who suffer from food allergies because they are not tested….”
The claim that genetically engineered crops are ‘understudied’—the meme represented in the quotes highlighted above—has become a staple of opponents of crop biotechnology, especially activist journalists. Anti-GMO campaigners, including many organic supporters, assert time and again that genetically modified crops have not been safety tested or that the research done to date on the health or environmental impact of GMOs has “all” been done by the companies that produce the seeds. Therefore, they claim, consumers are taking a ‘leap of faith’ in concluding that they face no harm from consuming foods made with genetically modified ingredients.
That is false.
Every major international science body in the world has reviewed multiple independent studies—in some cases numbering in the hundreds—in coming to the consensus conclusion that GMO crops are as safe or safer than conventional or organic foods. But until now, the magnitude of the research on crop biotechnology has never been cataloged. In response to what they believed was an information gap, a team of Italian scientists summarized 1783 studies about the safety and environmental impacts of GMO foods—a staggering number.
The researchers couldn’t find a single credible example demonstrating that GM foods pose any harm to humans or animals. “The scientific research conducted so far has not detected any significant hazards directly connected with the use of genetically engineered crops,” the scientists concluded.
The research review, published in Critical Reviews in Biotechnology in September, spanned only the last decade—from 2002 to 2012—which represents only about a third of the lifetime of GM technology.
“Our goal was to create a single document where interested people of all levels of expertise can get an overview on what has been done by scientists regarding GE crop safety,” lead researcher Alessandro Nicolia, applied biologist at the University of Perugia, told Real Clear Science. “We tried to give a balanced view informing about what has been debated, the conclusions reached so far, and emerging issues.”
The conclusions are also striking because European governments, Italy in particular, have not been as embracing of genetically modified crops as has North and South America, although the consensus of European scientists has been generally positive.
The Italian review not only compiled independent research on GMOs over the last ten years but also summarizes findings in the different categories of GM research: general literature, environmental impact, safety of consumption and traceability.
The “general literature” category of studies largely reveals the differences between the US, EU and other countries when it comes to regulating GM crops. Due to lack of uniform regulatory practices and the rise of non-scientific rhetoric, Nicolia and his colleagues report, concern about GMOs has been greatly exaggerated.
Environmental impact studies are predominant in the body of GM research, making up 68% of the 1,783 studies. These studies investigated environmental impact on the crop-level, farm-level and landscape-level. Nicolia and his team found “little to no evidence” that GM crops have a negative environmental impact on their surroundings.
One of the fastest growing areas of research is in gene flow, the potential for genes from GM crops to be found—“contaminate” in the parlance of activists—in non-GM crops in neighboring fields. Nicolia and his colleagues report that this has been observed, and scientists have been studying ways to reduce this risk with different strategies such as isolation distances and post-harvest practices. The review notes that gene flow is not unique to GM technology and is commonly seen in wild plants and non-GM crops. While gene flow could certainly benefit from more research, Nicolia and his colleagues suggest, the public’s aversion to field trials discourages many scientists, especially in the EU.
In the food and feeding category, the team found no evidence that approved GMOs introduce any unique allergens or toxins into the food supply. All GM crops are tested against a database of all known allergens before commercialization and any crop found containing new allergens is not approved or marketed.
The researchers also address the safety of transcribed RNA from transgenic DNA. Are scientists fiddling with the ‘natural order’ of life? In fact, humans consume between 0.1 and 1 gram of DNA per day, from both GM and non-GM ingredients. This DNA is generally degraded by food processing, and any surviving DNA is then subsequently degraded in the digestive system. No evidence was found that DNA absorbed through the GI tract could be integrated into human cells—a popular anti-GMO criticism.
These 1783 studies are expected to be merged into the public database known as GENERA (Genetic Engineering Risk Atlas) being built by Biofortified, an independent non-profit website. Officially launched in 2012, GENERA includes peer-reviewed journal articles from different aspects of GM research, including basic genetics, feeding studies, environmental impact and nutritional impact. GENERA has more than 650 studies listed so far, many of which also show up in the new database. When merged, there should be well over 2000 GMO related studies, a sizable percentage—as many as 1000—that have been independently executed by independent scientists.
In short, genetically modified foods are among the most extensively studied scientific subjects in history. This year celebrates the 30th anniversary of GM technology, and the paper’s conclusion is unequivocal: there is no credible evidence that GMOs pose any unique threat to the environment or the public’s health. The reason for the public’s distrust of GMOs lies in psychology, politics and false debates.
More on genetics and science literacy at the Genetic Literacy Project
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