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Published online 2 September 2009 | Nature | doi:10.1038/461027a
GM crops: Battlefield
Papers suggesting that biotech crops might harm the environment attract a hail of abuse from other scientists. Emily Waltz asks if the critics fight fair.
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I am one of the people who published a critical commentary of the Rosi-Marshall paper (see ref. 9 obove). Here are my further comments about the piece above.
i. The main reason for the strong criticism of papers like Rosi-Marshall is exactly about bad science with major policy implications.
If I publish a paper about sex determination in asparagus that has no interest beyond the scientific circles, then it does not damage anybody beyond these circles if it is wrong and the damage is mild. On the contrary, when a paper claiming problems with transgenic plants is published, it may be used by people opposed ideologically to ag-biotech.
We have seen this in the past with Loosey, Chapela and others. These papers have been used or are used to prevent introduction of the technology in several European countries and, as a consequence, in several other countries in the third world. Even if the content of the papers is later dismissed as irrelevant or wrong, the claims are still propagated for years. Papers that could have an influence on policy and regulation for years must be screened by editors and referees with the utmost care first and then by the scientific community at large once they have been published.
The scientific community has the moral obbligation of looking more carefully into matters which could impact many more people, both positively or negatively.
ii. A truly constructive criticism in science must have one aim: seek the truth.
The role of peers (referees and later colleagues who read the paper) is to help authors to do this. It is a matter of humility to submit your own research results to the scientific world. If you can't stand this sort of criticism, you are loving your results more than the truth. Sometimes the wording of the criticism may be more or less pleasing (whoever has received referees comments on a manuscript knows it very well). Things lived with passion bring often excesses in feelings. But what matters more is the end result.
iii. These papers do not “alert us to possible reasons to look into this more carefullyâ€. A research badly designes, for instance with no proper controls or with unreasonable doses completely out of real life range or situation is simply irrelevant and does not advance our understanding and may even be misleading further research. A wonderful example of this is the data accumulated on synthetic substances with test for carcinogens made at high dose in the 70s-80s. They turned out to be deadly wrong and said nothing about the effect at the real doses we are exposed to. Rather than alert about possible reasons to look more into this, they concealed the reality for many years because people did not do the proper control with natural substances (which had the same frequency, 60%, of carcinogens as synthetic substances).
Bad science caused bad regulation and unnecessary spending as well as useless research. Try interview Bruce Ames (professor of Biochemistry at Berkeley) on this or read some of his pieces:
http://potency.berkeley.edu/pdfs/Paracelsus.pdf
or a video: http://www.bruceames.org/bnalect.cancer1.php
Looking at a transgenic corn causing a reduction on non target organisms without comparing the effect of a conventional corn treated with insecticides is a non real world situation. In Italy this year we are experiencing a strong outbreak of root corn borer. They are treating with insecticides but nobody measures the effect on biodiversity.
iv. I see much more depressing for scientists spending years on developing a new product to see thir research fields destroyed or their products not brought to the market because of insane regulatory burden.
These regulations, especially in the EU, are fuelled by bad science and ideological opposition.
Golden rice is a prime example of unjustifiable delay. I know of several other
products with real benefits which never made it to the market.
P. Morandini, Dept. of Biology, University of Milan (Italy)
It was with surprise that I read Emily Waltz 's article "Battlefield". Waltz used the word "attack" four times in the article yet never once put forward evidence of anything other than challenges to the science methodology, interpretation, incomplete citations, over reaching conclusions etc. Attempting to claim victim status is a very successful method used to avoid the real issue, in this case the BAD Science. I was left wondering if the intent of the article was to quiet the scientific criticisms. As far as I can determine the scientific criticisms were right on the mark. It is too bad Emily Waltz and Nature did not appear to understand this point. When poor quality science goes unchallenged we all lose.
Robert Wager
Vancouver Island University
Nanaimo BC
Canada
robert.wager@viu.ca
The critics' claim that EU regulation on GMOs is "fuelled by bad science and ideological opposition" betrays the critics' own ideological position and scientific hubris. Quite a few peer-reviewed papers have been publiched in peer-reviewed journals, based on rigorous methodlogy and long-term field data, which unamiguously show adverse impacts of GM crops on biodiversity (for example, Bohan et al. 2005, Proc. Royal Soc. B 272, 463–474). Critics who are so earnest about "good science" are surprisingly silent about such publications. They never write letters to policy makers suggesting immediate ban of herbicide tolerant GM crops in all countries.
Similarly, Saxena's work on the significant larvicidal effect of Bt-root exudates from Bt corn hybrids, representing three transformation events (Bt11, MON810, and 176) and evaluated in both in vitro and field studies (Saxena D., S. Flores, and G. Stotzky 2002, Soil Biology & Biochemistry 34, 133-137) is neither cited nor noticed by these self-righteous critiques. A number of excellent studies (cited in Séralini et al. (2009, Int. J. Biol. Sci. 5: 438-443) are fated to disappear from the view of policy makers and the public through the "conspiracy of silence".
Contrariwise, when a truly bad paper, reporting absurd findings, was published in a reputed journal like Science, the responsibility and righteosuness of these same critiques, like the Pharaoh's horses behind Moses, sank into the deep sea. This particular study (Qaim, M., & Zilberman, D. 2003, Science 299, 900-902) found up to 83% yield increase in Bt cotton, based on farmer interviews and "trial records" supplied by Mahyco-Monsanto – the company who conducted those putative trials, and obviously had stake in such publications. Moreover, the study did not consider the confounding effects of late (by 2 months) sowing of the crop, and of better water supply to the Bt-cotton fields compared to the non-Bt varieties. When GM crops are promoted at the expense of scientific rigor and sensibility, the whistle blowers cannot find their whistles, or else are out of their breath to blow the whistles.
What surprises me most is the critics' evasion of the fact that Bt toxin is a known insecticide, and biotechnologists have chosen this toxin for incorporation into crop plant precisely for that purpose. However, whenever a study shows a toxic effect on non-target insects, it is immediately branded as "bad science". It requires little understanding of insect physiology to surmise that continuous flux of the insecticidal toxin from a Bt-plant source into the soil and run-off water is likely to eliminate at least some non-target insects. One may argue about the exact extent of mortality of this or that species, but the lethal effect of Bt toxin on non-target insects is well established (see Hilbeck, A. and J.E.U. Schmidt 2006, Biopestic. Int. 2 (1): 1-50). The effect is certain when insect predators and parasitoids consume "Bt-susceptible and sublethally-damaged herbivores" (J., M. Meissle & F. Bigler 2006, Nature Biotechnology 24: 63 – 71). Do the critics perceive any policy implication of these findings?
Debal Deb
Centre for Interdisciplinary Studies, Barrackpore, India. (Current address: Energy & Resources Group, Uinviersity of California- Berkeley)
debaldeb@wildmail.com
Dear Sirs, it is just the other way around: it is the duty of serious scientists to criticize weak or junk science, simply in order to at least make a remark for those who can read that there is a piece of weak or junk science. We have seen again and again that in a world triggered by a greenish mainstream any piece of science which casts some doubt on GM-plants will be pimped up by NGOs, media and scientifically illiterate politicians for justifying unjustifiable political actions. The most recent one is the ban of Mon 810 by the german minister of Agriculture and some other European governments, which is based on extremely weak science. It is also common experience made by many of those scientists working on GM-plants at universities or public research institutes that they are accused by NGOs or greenish politicians as being bought by the multinationals, not to name hate mails, blogs or other types of harassments. In case Emily Waltz needs names, she is free to contact me.
Posted on behalf of Hans-Joerg Jacobsen, Leibniz Universität Hannover, hj_jacobsen@mac.com
Waltz's News Feature 'GM crops: Battlefield' about genetically modified crops that produce insecticidal toxins from Bacillus thuringiensis (Bt) notes that our review summarizing evidence of insect resistance to Bt cotton was challenged by a scientist who now works for Monsanto. We would like to point out that resistance to Monsanto's Bt cotton that produces toxin Cry1Ac is well documented in some U.S. populations of bollworm (Helicoverpa zea), a major cotton pest (B. E. Tabashnik et al., Nature Biotechnology 26, 1074-1076; 2008). The evidence includes control problems in the field, increased survival of insects on Bt cotton leaves, and extensive laboratory bioassay data. Rapid resistance was anticipated in this case because the crop does not deliver a sufficiently high dose of toxin against this pest (http://www.epa.gov/scipoly/sap/meetings/1998/0298_mtg.htm). We also note that Monsanto allowed its U.S. registration of Bt cotton producing Cry1Ac to expire in September 2009. Sales have been shifting largely to Monsanto's newer Bt cotton that produces Cry1Ac and Cry2Ab, which is more effective against Cry1Ac-resistant insects.
Although most targeted pest populations remain susceptible to Bt crops, undisputed evidence of insect resistance to Bt maize has been reported from Puerto Rico and South Africa (S. R. Matten et al. 2008, pp. 27-39, in J. Romeis et al. [eds.], Integration of Insect Resistant Genetically Modified Crops within IPM Programs. Springer, New York; M. Kruger et al., Crop Protection 28, 684-689; 2009). In Puerto Rico, sales of GM maize producing Bt toxin Cry1F have been suspended because of insect resistance. Although planting "refuges" of non-Bt crops to delay resistance by promoting survival of susceptible insects is required in many countries, low farmer compliance with this strategy probably hastened evolution of resistance in South Africa.
While attempts to discount documented cases of insect resistance to GM crops are counterproductive, systematic analyses of such examples can enhance understanding of pest evolution and yield insights that help to boost the durability of GM crops for insect control. More generally, we encourage scientists to set aside passions for or against GM crops and focus instead on bringing evidence to bear on the issues. Objective, rigorous evaluations on a case-by-case basis can help to resolve controversies, limit negative impacts of GM crops, and maximize their benefits.
Bruce E. Tabashnik, Yves Carrière
Department of Entomology
University of Arizona
brucet@ag.arizona.edu, ycarrier@ag.arizona.edu