Agriculture Reference
In-Depth Information
The U.S. FDA concluded in 1980 that WFS lacked power, were fraught with confound-
ers, and were not suitable for the evaluation of potentially toxic molecules produced
in food through processes such as irradiation or thermal processing. The FDA con-
cluded the preferred approach was direct analysis of the suspect compounds coupled
with 90-day rat studies on pure compounds of interest to determine NOAEL, LOAEL,
LD50, and ADI. The reason for this can be found in simple arithmetic. It can be cal-
culated that, based on the known toxicities and amounts that could be present, taken
together with the amount consumed, the low levels of potentially toxic molecules pres-
ent in the unanalyzed portion of foods or feeds derived from transgenic crops would
not constitute a high enough dose to cause adverse effects in such studies. Even highly
toxic molecules would most likely be present at levels below the level of toxicological
concern. A more practical consideration for avoiding WFS is that these kinds of studies
require considerable resources, are time consuming, are subject to significant biological
variability unless large numbers of animals are used, and suffer from a number of other
confounders. A serious ethical question arises from the use of so many animals in weak
and pointless studies (on ethical questions in food generally, see Korthals, this volume).
In spite of the questionable merit of WFS, many WFS have been performed in a num-
ber of animal species testing various transgenic crops (van Haver et al. 2008: Snell et al.,
2012, Bartholomaeus et  al., 2013). Regulatory agencies in some jurisdictions require
WFS to be conducted as a routine part of the premarket regulatory review. The U.S.
FDA does not require WFS, and, in recent years, EFSA has stated that WFS are not a
required part of the dossier for a new transgenic variety (van Haver et al, 2008).12 Whole
food studies also have been performed by independent researchers and reported in
the peer-reviewed literature. The findings from these studies can be summarized fairly
simply. Those studies that were carefully designed and conducted, and which followed
widely accepted international guidelines, uniformly and without exception found no
biologically significant differences between transgenic and nontransgenic counterparts
(van Haver et al., 2008; Kuntz and Ricroch, 2012 Bartholomaeus et al., 2013). Results
from those studies that did not follow internationally accepted protocols can be divided
into a small group that observed one or more statistical differences between control and
test groups in measured parameters, and a larger group that failed to observe any differ-
ences that could be attributed to the transgenic crop content of the feed.
A few researchers have made sensational claims about potential adverse effects asso-
ciated with consumption of transgenic crops based on animal studies. These claims
have been amplified and distorted by opponents of transgenic crops in an attempt to
scare consumers and political decision makers. Among the first of these were Ewen
and Pusztai (1999) who claimed that feeding GM potatoes to rats caused “cancerous
and precancerous” changes in gastrointestinal epithelial cells. Critical analysis of the
work by a Royal Society (UK) expert panel, among others, concluded that no mean-
ingful scientific conclusion could be drawn from the work due to numerous flaws in
the experimental design, conduct, and analysis (The Royal Society [UK], 1999). Others
publications based on WFS with transgenic and conventional food and feed crops have
reported a variety of differences between test and control animals such as differences
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