Posted: July 2014
Perspective Matters: Bias and Conflict of Interest in Studies About
Genetically Modified Organisms
All research is initiated, planned and carried out by scientists who have
a variety of interests that influence their choices, procedures, analyses,
and conclusions. In other words, there is a larger-than-science context
for every experiment and for the assessment of its results.
The question of whether genetically modified (GM) crops and food are safe
is highly contested. Surveys of studies on the safety of GM crops have
focused primarily on potential environmental and health risks to human
beings. Studies on health risks usually involve giving animals feed
containing GM products; no epidemiological studies on human health have
been carried out.
Well-qualified scientists can come to strikingly different assessments of
the significance of the same studies. It’s not hard to understand, for
example, that ecologists concerned about biological diversity will carry
out a study on the impact of a GM crop on the environment with different
critical framework than a crop scientist who works for a biotechnology
company that developed and sells the seed.
The universe of concern that informs a scientist’s work is usually not
presented in a peer-reviewed scientific journal. Much is bracketed out
through the objectified form of presentation. But because of the
increasing degree to which science has become bound to commercial
interests, more journals have begun to require at least a statement by
authors about competing financial or professional interests.
Any scientist who carries out research knows the biases and predilections
of the journals he or she hopes to publish in. The journal Transgenic
Research, for example, publishes articles concerned with genetic
engineering. The two editors are practitioners and vocal proponents of
genetic engineering: Paul Christou helped invent the particle bombardment
method of genetic transformation in plants while working at a genetics
company that was later bought by the Monsanto corporation, which now holds
the patents on the work that Christou invented; Bruce Whitelaw, the other
editor of the journal, works at the Roslin Institute in Scotland and does
research on genetically modified farm animals. It is perhaps not
surprising that the articles in this journal that mention unintended
effects usually say that none were found. The phrase “no adverse effects”
is used in many articles and you are hard pressed to find any article that
mentions adverse effects in this journal. Also, authors do not need to
state whether they have competing interests.
In contrast, the journal Environmental Sciences Europe has an
environmental/ecological focus. It deals with many areas, including
genetically modified crops, especially in relation to regulation issues.
The editor is a university scientist and an expert in bioanalytical
environmental toxicology. In this journal you do find articles that report
on unintended effects of genetic modification in relation to the
environment. Authors must state competing interests and, interestingly,
the journal has published exchanges between research groups reporting on
unintended effects and others who contest those findings.
Unsurprisingly, a review of safety assessments of GM plants — by university
scientists — found that “most of the studies demonstrating that GM foods are
as nutritional and safe as those obtained by conventional breeding have
been performed by biotechnology companies or associates, which are also
responsible for commercializing these GM plants” (Domingo & Bordonaba,
2011). They found, overall, an “equilibrium” in the number of research
groups suggesting that GM crops (mainly corn and soybeans) are as safe and
nutritious as conventional crops and those that raise “serious concerns”
about the safety of GM plants for animal and human consumption.
Diels et al. (2011) looked into whether there is any correlation between
research outcomes and financial or professional conflict of interest. They
evaluated 94 different studies and found that “either financial or
professional conflict of interest was associated with study outcomes that
cast genetically modified products in a favorable light.” Especially when
the authors were affiliated with the industry was there a strong
association with favorable findings. If the funding source alone was the
source of conflict of interest, there was not this kind of strong
correlation with positive assessment of results. However, of the 41
articles that included industry-affiliated authors, only seven declared
their funding source.
There are small beacons of light in this often opaque landscape. I’m
thinking, for example, of articles by Wendy Pline-Srnic, who as research
scientist at the biotech company Syngenta, reported on unintended effects
in GM cotton (see, for example, our report:
Morphology Was Altered When Glyphosate-Resistant Cotton Was Sprayed with
A report by Séralini et al. (2012) generated major controversy in the
scientific community and in the public debate about the safety of GM food.
The researchers fed rats feed containing herbicide-resistant GM corn
(NK603) over a period of two years — the first long-term feeding study of
its kind. They reported that female rats fed with the GM corn containing
feed died earlier and more of the animals died than control rats fed
normal feed. They also were more likely to develop mammary tumors and male
rats had pathologies in the liver and kidneys. The study was criticized in
the popular press, in scientific journals and also by the European Food
Safety Authority (EFSA). The latter came to the conclusion that the study
was defective, both conceptually and methodologically. The journal
retracted the article, which the authors had refused to withdraw (see
Séralini et al. 2013).
Meyer and Hilbeck (2013) analyzed risk assessment studies of this GM corn
that were subsequently released by EFSA. They included Monsanto’s
technical report to EFSA. (Monsanto had developed the GM corn variety.)
Using the same criteria that EFSA used to critique the Séralini study,
Meyer and Hilbeck found that all the studies “suffered from comparable
deficiencies [and] all of them satisfy or fail to satisfy the EFSA
evaluation criteria to a comparable extent; the rejection of only one of
the papers is, thus, not scientifically justified. ... We did find
critical double standards in acceptance and rigor of the evaluation of
Just as any statement about the function of a gene is only meaningful if
one knows something about its organismic and environmental context, so are
the results and conclusions of scientific studies highly
context-dependent, and this context includes the universe of concern that
informs all aspects of a scientist’s work. For this reason it is
problematic that U.S. regulatory agencies rely solely on safety and
environmental assessments that have been carried out by the companies that
are themselves seeking approval for their genetically modified organisms.
Diels, J., M. Cunha, C. Manaia et al (2011). “Association of Financial or
Professional Conflict of Interest to Research Outcomes on Health Risks or
Nutritional Assessment Studies of Genetically Modified Products,” Food
Policy vol. 36, pp. 197-203.
Domingo, J. L. and J. G. Bordonaba (2011). “A Literature Review on the
Safety Assessment of Genetically Modified Plants,” Environment
International vol. 37, pp. 734-42.
Meyer, H. and A. Hilbeck (2013). “Rat Feeding Studies with Genetically
Modified Maize — A Comparative Evaluation of Applied Methods and Risk
Assessment Standards.” Environmental Sciences Europe vol. 25, pp. 33ff.
Séralini, G. E., E. Claire, R. Mesnage et al. (2012). “Long Term
Toxicity of a Roundup Herbicide and a Roundup-Tolerant Genetically
Modified Maize,” Food and Chemical Toxicology vol. 50, pp. 4221–31.
Séralini, G. E., R. Mesnage, N. Defarge et al. (2013). “Answers to
Critics: Why There Is a Long Term Toxicity Due to a Roundup-Tolerant
Genetically Modified Maize and to a Roundup Herbicide,” Food and Chemical
Toxicology vol. 53, pp. 476–83.
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