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Response by Dick Atlee to
The Evidence on GMO Safety
Posted on April 28, 2013 by Ramez Naam
Mr. Naam's initial disclaimer:
Beyond the points in this article, the issue of the driving out of seeds adapted over millennia of breeding to a wide variety of environmental situations is not addressed. The loss of gene pool biodiversity will inevitably become dangerous as the climate begins to be less predictable and the need for material for hybridization becomes ever more important.
My responses to Mr. Naam's points are presented in italics.
The US National Academy of Sciences
This is the premier scientific body in the United States. They have repeatedly found genetically modified food safe, noting that after billions of meals served, "no adverse health effects attributed to genetic engineering have been documented in the human population."
They've also found that genetically engineered crops are kinder to the environment than non-genetically engineered crops. The National Academy of Science's 2010 report, Impact of Genetically Engineered Crops on Farm Sustainability in the United States, found that GM crops planted to date had reduced insecticide use, reduced use of the most dangerous herbicides, increased the frequency of conservation tillage and no-till farming, reduced carbon emissions, reduced soil runoffs, and improved soil quality. The report said that, "Generally, GE (GMO) crops have had fewer adverse effects on the environment than non-GE crops produced conventionally."
The American Association for the Advancement of Science
This is the largest organization made up of professional scientists in the United States, and also publisher of Science magazine, one of the two most respected scientific journals in the world. The AAAS says "The science is quite clear: crop improvement by the modern molecular techniques of biotechnology is safe."
As an example of the non-scientific approach of Science magazine on this issue, their September 2013 endorsement of beta-caroteine fortified Golden Rice as the solution to vitamin-A deficiency in the Third World ignored a number of important points:
The magazine's ignoring of these serious issues raises questions about its position on the issue of GMOs, quite apart from whether its "respectedness" may or may not be warranted on others.
The American Medical Association
The premier body of physicians in the United States. They have consistently found genetically modified foods as safe to eat as any other food, stating "there is no scientific justification for special labeling of genetically modified foods".
The European Commission
Europe is extremely anti-GMO. But even there, the scientific community is clear that genetically modified foods are safe. The scientific advisor to the European Comission has said "there is no more risk in eating GMO food than eating conventionally farmed food".
The European Commission's 2010 report on genetically engineered food (based on independent research not funded by any biotech company) said: "The main conclusion to be drawn from the efforts of more than 130 research projects, covering a period of more than 25 years of research, and involving more than 500 independent research groups, is that biotechnology, and in particular GMOs, are not per se more risky than e.g. conventional plant breeding technologies."
Royal Society of Medicine
England's top medical society, the British equivalent of the American Medical Association, published a review of all the information about genetically modified foods that concluded, "Foods derived from GM crops have been consumed by hundreds of millions of people across the world for more than 15 years, with no reported ill effects (or legal cases related to human health), despite many of the consumers coming from that most litigious of countries, the USA."
The Largest Ever Review of Studies on GMOs
In 2013, a group of Italian scientists (from a country where no GMOs are grown) conducted the largest-ever survey of scientific information on genetically modified foods. They looked at 1,783 published research papers, reviews, and reports on GMOs. What they found was no evidence of harm.
"The scientific research conducted so far has not detected any significant hazards directly connected with the use of genetically engineered crops."
Who were these Italian scientists? What does "significant" mean? What does "directly connected" mean. Once you start injecting scope-limiting adjectives, you have to look at the raw data -- to what extent was the research good -- and once you also include reviews and reports, to what extent are these "double" counting the research.
The French Supreme Court
The French Supreme Court isn't a scientific body, but I mention them here because their recent decision was so remarkable. France is a very anti-GMO country. Yet the French Supreme Court struck down France's GMO ban, ruling that the government had shown no credible evidence of any harm to humans or the environment. You can read about that here.
Don't GMOs Cause Cancer in Rats? Or Infertility?
Thus far there have been several hundred studies on the safety of genetically engineered food. All but a handful have found them completely safe. The only studies that have found that genetically modified foods harm animals (the ones quoted as saying that they cause cancer and infertility) all come from one laboratory, that of Gilles-Éric Séralini in France.
Keep in mind that Séralini was the first person to extend the "typical" but seldom-done 90-day rat feeding studies (8-9 year human equivalent) to 2 years (lifetime equivalent). It is important to understand that he followed to the letter Monsanto's own 90-day study (harm evidence from which was suppressed until the raw data was forced into the open by legal action) in terms of design and number and strain of rats. He simply extended the time and increased the variety of feeding groups and parameters measured. The Monsanto study was designed as a toxicity study, and so was Séralini's -- NOT as a carcigenicity study. He did not expect to find tumors.
Yet Séralini's studies have been widely debunked. The study linking GMOs to cancer was forcibly retracted by the journal that published it (something very rare in science).
It should be mentioned what "forcibly" actually means. In fact, the industry put huge pressure on the editor of the journal, who violated all the principles of scientific publication and his own publication's guidelines by removing the article. His only comment was that the results were "not conclusive," which would, of course, eliminate almost every article ever published in a scientific journal. The point of publishing research is to stimulate others to try to replicate it to confirm or reject it.
In a previous example of this, Arpad Pusztai's 1996 research, the editors of the journal in which it was published resisted massive industry and government pressure to rescind his paper.
In fact, the study, was clearly flawed from the beginning. It was immediately criticized by the six major French scientific academies and by neutral scientists and science journalists not affiliated with biotech companies.
Unmentioned are the large groups of scientists who came out in support of Séralini's study, criticizing the removal of his journal article.
The primary basis of the criticism was that it was improperly designed. The explicit or implicit assumption underlying this is that there were not enough rats for a carcigenicity study, and the rats were of a strain susceptible to tumors. The fact that the study was identical to Monsanto's in these respects -- i.e., designed for toxicity testing, not carcigenicity -- was ignored or deliberately suppressed by these attacks.
Perhaps most damning is the way in which Séralini manipulated the press. He refused to allow science journalists to see the actual paper before publication day, preventing those journalists from going through their normal process of calling scientists to get opinions about the results before writing up their news stories. As award-winning science journalist Carl Zimmer (also not affiliated with any biotech firm) wrote, science journalists were played.
Given what happened to Arpad Pusztai back in 1996, when he was fired from his 35-year position as one of the foremost investigators in the world after he found organ degeneration and tumors, and he and his research team was gagged with threat of a lawsuit from Monsanto, it is no surprise that Séralini would be concerned about a response. His concern was born out by the commencement within a couple of hours of a world-wide attack on him, before anyone could have adequately evaluated his work. It was just one indication of the pressure that would have been exerted to prevent publication.
Even GMO opponents found the rat-cancer link hard to believe. My fellow guest on MSNBC, food policy advocate (and GMO opponent) Marion Nestle, herself said that she found the Seralini study linking GMOs to cancer hard to believe. Marion Nestle writes:
"These results are so graphically shocking (see the paper's photographs), and so discrepant from previous studies (see recent review in the same journal), that they bring out my skeptical tendencies. (Note: Although Séralini is apparently a well known opponent of GMOs, his study -- and that of the review -- were funded by government or other independent agencies.) ...the study is weirdly complicated."
Again, these comments deliberately ignore or avoid the fact that Séralini and his colleagues were caught completely off guard by the appearance of tumors, the first of which appeared a month after the 90-days that the Monsanto study ran. No previous study of this sort had been done, so the fact that the results departed from previous studies is completely unsurprising. The investigators have openly stated that their study was not designed to establish carcigenicity. The appropriate scientific response to this situation is exactly what Séralini's group called for -- further study to find out what's actually going on here. His opponents are doing exactly the opposite.
Long Term Safety Studies
A common myth is that there are no long-term safety studies of GMOs. There have, in fact, been dozens of long-term studies of feeding GMOs to animals for their entire lives, sometimes for as many as ten generations in a row, with no ill effects discovered whatsoever. Here's a good survey of long-term and multi-generation GMO safety studies.
Some of these studies relate to salmon and quail, with which I'm not familiar. Rats are considered the basis for possible human-related issues. Some of these studies just looked at macro issues, such as blood composition and weight of body and organs. Some found parameters "within a normal range," when this often masks the inclusion of all kinds of strains of rats, instead of just the rats under study (I'm not asserting this was the case in this study). Some of them seemed to get at the more fundamental issues, so it would be interesting to get the anti-GM analysis of these.
The report on dairy cattle showing no effects, however, really makes me wonder about such studies. This flies in the fact of the experience of hundreds of farmers, including many in a carefully designed peer-reviewed study. Cattle refuse to eat GMO corn if given the option, and if they have no choice, they develop a variety of serious, life-threatening conditions that clear up quickly after GMO feed is replaced with normal corn. The same is true of pigs.
Independently Funded Studies
Another common myth is that Monsanto or other biotech companies control all biotech research, preventing independent research from happening. This is not the case. Two sets of independent studies:
- The European Commission Report I mention above includes 130 independent studies, paid for by the EU, conducted by more than 500 teams.
- BioFortified maintains a (largely distinct) list of more than 120 independently funded studies which were conducted outside the biotech industry and without biotech dollars.
A Scientific Consensus
All together, the scientific consensus around the safety of genetically modified foods is as strong as the scientific consensus around climate change. These foods have been studied more than any other, and everything tells us that they're safe.
Update: Other Common Concerns on GMOs
I receive a few other frequent questions on GMOs that don't relate to safety, so answering three of the most frequent here:
What About Superweeds?
Pesticide resistance is a real thing. It's also an old thing. The first notion that it exists dates back to 1914, when A.L. Melander published a paper asking "Can insects become resistant to sprays?" Realistically, resistance has been evolving for the 4,000 or so years that humans have been using pesticides.
It would be interesting to know what the nature of "pesticides" are that humans have been using for 4000 years. Natural plant based pesticides evolve to control pests, the pests eventually develop resistance, and the plant then adapts further, in a long, gradual process. The concentrated use of chemical pesticides is a phenomenon of the last century or less. Bacteria-based Bt insecticide has been around forever, but the corn root worm had no resistance to it until the advent of Bt-producing GMOs. Farmers were told to reserve 20% of their field for non-GMO, so that there would be a supply of non-adapted insects to compete in mating with any that developed resistance. Scientists predicted that anything less than 50% would result in rapid resistance development. Farmers in large part ignored the advice, and now will have to turn to far more dangerous insecticides.
It's clear today that weeds are becoming resistant to glyphosate (Roundup) and that this is threatening the use of roundup. It's not at all clear that this has anything to do with GMOs, however. The rate of the evolution of new pesticide resistant weeds appears to be the same for GMO vs. non-GMO crops. That doesn't make the problem any less important. But it suggests that pointing the finger at GMOs is missing the point.
The unfortunate fact for this argument is that RoundUp has been around for a long time, but the superweeds only developed after GMOs caused a massive increase in the use of RoundUp. The claim that they existed before GMOs (except as some rarity) is absurd -- Monsanto couldn't have sold GMOs on such a large scale if RoundUp had been seen to be failing against weeds.
Trying to claim that "superweeds will develop anyway," regardless of GMOs, is particularly dangerous, because the obvious take-away from that argument is that we just have to engineer a resistance to a different herbicide, and on and on into more dangerous and damaging materials. This does not lead to sustainability by any stretch of the imagination.
What About Farmer Suicides in India?
The allegation has been made that GMOs have been driving farmers in India to commit suicide. Farmers in India do commit suicide, and every one of those is a tragedy.
However, the farmer suicides started long before GMOs were introduced to that country, and the suicide rate has held steady or slightly dropped since GMOs were introduced.
Every suicide is a tragedy, but linking them to GMOs is false.