On The Flavr Savr Issue
Have you ever tried to get information from online about the Flavr Savr tomato studies on rats? I went looking the other day for details on why the FDA did not prohibit their sale, given that rats fed the transgenic tomatoes developed lesions in their digestive systems. A number of websites owned by holistic practioners, dieticians and anti-GMO groups love to cite this report and complain that the FDA was not doing its job. Each of the sites I found quoted the same document and referred me back to the same webpage that supposedly had the document posted, biointegrity.org. However, the links all lead only to a 3-page memo to Dr. Linda Kahl of the FDA ("Flavr Savr Tomato: . . . Pathology Branch's Evaluation of Rats with Stomach Lesions From Three Four-Week Oral (Gavage) Toxicity Studies . . . and an Expert Panel's Report," June 16, 1993).
The Action BioScience webpage was a little less alarmist, giving more details about the studies and saying only that the FDA approved the tomatoes because the studies were poorly designed. Agreeably, that's just about as bad as approving something when the data decisively indicate it's not safe, but clearly the problem here was that there simply weren't adequate proceedures in place to address the situation (gene cloning in our foods). The result was a hot bioethics debate having nothing really to do with whether or not the tomatoes were safe.
That said, I do believe if you are going to crucify the Flavr Savr tomatoes, or any other food biotechnologies, the data you use should at least be relevant. My first reaction to this story was to wonder exactly how much tomato was fed to the rats – knowing that in pesticide studies, animals are often exposed to far higher doses than a human would reasonably experience. I was assuming that rats aren’t generally accustomed to eating a diet of such acidity. Also, remember that, while rats and mice make good test subjects, their metabolic systems are not identical to humans. Secondly, I was wondering if the GM tomatoes were somehow more acidic than the parent strain from which they were derived.
After a VERY LONG search, I finally found a memo buried in the FDA website, that summarized the studies. What I read gave me an answer to my first question, and it's pretty clear to me why the rats got the lesions: They were fed the human equivalent of at least 10 large or 40 small (plum) tomatoes per day (see page 13). I don’t know about you, but if I ate that many tomatoes every day for 28 days, I'm pretty sure I’d get an ulcer too!!
Comments
I am so very shocked and disappointed to read what was written about the Flavr Savr tomato. I am very disappointed with this website and not only with the author, so disappointed that I WOULD UNSUBSCRIBE AFTER THIS COMMENT.
Where do I begin and end my comment: EVERY THING said is rubbish: The author said that she did not “believe” that all G.M. Foods are not safe. A scientist or anyone who writes a bio-science piece should not use the word “believe”.
In fact, the mathematical, biological, physical, chemistry, engineering and other precise or exact sciences do not rest on belief. They rest on knowing which is based on fact, exactitude and precision arrived at through mathematics and laboratory experiments. What did Rene Descartes say about science? Note that religion was dismissed on the ground that it is based on belief.
What is worst about what the author wrote about G.M Foods: She did not provide even one evidence of one safety assessment of any G.M. Food which was carried out in public by an independent body and certified or confirmed to be safe. NOT EVEN ONE!!!!!
After the Flavr Savr failure of safety assessment or test, the principle that was created for the USFDA and was adopted for universal application is the unscientific, senseless and criminal Substantial Equivalence principle. Does equivalence mean safe? No; not even identical or the same!!!!!
The issue is: Is G.M. Food safe?. I want to be informed of any G.M. Food that has been certified safe by an independent body after a public safety assessment or test. Since I am unsubscribing, I should be informed through Chimeawele@yahoo.com and not through this paid-to-campaign-for-G.M(death)Food website.
I recommend that the lady author offers herself for the human test of the safety of G.M. Foods that is so very much necessary to prove her belief as well founded or not founded at all.
Prince Pieray C. P Odor
Lagos, Nigeria
Just a quick response to your comment: I’m afraid you’ve missed my points which were 1) the FDA was not equipped to handle the controversy thus the studies that were done didn’t follow any particular protocol, unlike the stringent tests required for new drugs. This left the issue up in the air because there were so many differing opinions as to how the GM foods should be tested and what constitutes “sufficient” testing.
2) It’s obvious that if you ate that many tomatoes you would have digestive problems. That doesn’t mean the tomatoes were safe, it just means that, yes, more testing should have been done, using protocols that were realistic.
I’m not an expert in the field of genetics but what is an obvious “no brainer” to anyone that Genetic modification so dangerous needs to take a good look at history.All foods we eat are genetically modified through hybridization.
So I asked what’s the difference between turning particular genes on or off ,aside from the time taken,in a lab or through Hybridization.
The biggest danger of GM is the development of “Chimera” and the use of “Eugenics”.After all a line needs to be drawn some where.
Joseph, the difference between selective breeding and genetic engineering may not be obvious to you, so let me explain some KEY differences. 1. Selective breeding does not CHANGE the genetic code. It only allows different expressions of genes ALREADY in the genetic code of the parents. 2. Genetic engineering introduces NEW genes into the organism that were not there and the proteins created by this new DNA have not been tested for human compatibility nor carcinogenic or other deleterious effects. I hope that makes things more clear!
Jessica, nowadays it is common practice to cross cultivars such as tomato with their wild relatives that do not belong to the same species. This often leads to substitution of large parts of chromosomes. It is very well possible that these pieces of chromosomes contain genes that were not present (anymore) or not active in the tomato genome. As such introduction of new genes also occurs in non-gmo breeding practice.
In addition Flavr Savr contains a transgene that silences a endogenous complementary gene. It does not encode for a protein which could be toxic, in fact, there is no extra protein. However, old fashioned transformation techniques included the transfer of a marker gene to select for the transgenic plants. Presently this is not necessary anymore.