GMO Myths and Truths

GM process by artificially widening the range
of values compared beyond what can be
scientifically justified. The practice runs counter
to the aim of scientific experiments, which
are designed to minimise variables. According
to rigorous scientific practice, in any single
experiment, the scientist manipulates just one
variable in order to test its effect. In this way,
any changes that are observed can be traced to a
probable single cause.
In an animal feeding trial with GMOs, the
manipulated variable is the GMO. One group
of animals, the “treated” group, is fed a diet
containing the GMO. Another group, the
control group, is fed a similar diet, with the only
difference being that it has not been subject
to genetic modification. All conditions of the
experiment outside the GM component of the
treated group’s diet must be the same. Within
this tightly controlled setup, any changes seen in
the treated group are likely to be caused by the
GM process.
Therefore, in any experiment to discover the
effects of a GMO in an animal feeding trial, the
only valid comparator is the control group within
that same experiment (the concurrent control).
By comparing the treated group with a wide
variety of control groups from other experiments
(sometimes called “historical control data”), GM
proponents are masking the effects of the GM
process or GM diet, as any GM-related changes
will disappear in the “noise” of the changes caused
by many variables.
3.1.5. Regulators currently do not
require long-term tests on GMOs
In order to detect health effects caused over time
in humans eating GM foods, long-term (chronic)
animal feeding trials are needed. But currently, no
long-term tests on GM crops or foods are required
by regulatory authorities anywhere in the world.
Reproductive and multigenerational tests, which
are necessary to discover effects of GM crops or
foods on fertility and future generations, are also
not required. 11
This contrasts with the testing requirements
for pesticides or drugs, which are far more
stringent. Before a pesticide or drug can be
approved for use, it must undergo one-year,
two-year, and reproductive tests on mammals. 12
Yet GM foods escape such testing, in spite of the
fact that virtually all commercialised GM foods
are engineered either to contain an insecticide or
to tolerate being sprayed with large amounts of
herbicide, so they are likely to contain significant
amounts of pesticides.
The longest tests that are routinely conducted
on GM foods for regulatory assessments are 90day
rodent feeding trials, and even these are not
compulsory. 11 While a 2012 EU draft regulation
requests such tests for the time being, the wording
is weak and foresees a situation in which they
are not required. 41 Also, the type of findings that
would trigger a regulatory requirement for such
tests has not been specified. 42
Such 90-day rodent trials are medium-term
(subchronic) tests that correspond to only a few
years in terms of human lifespan and are too short
to show long-term effects such as organ damage
or cancer. 43 In addition, too few animals are used
in these industry tests to reliably detect harmful
effects.
In spite of these serious shortcomings of
regulatory tests, statistically significant harmful
effects have been found even in industry’s own
90-day rodent feeding trials. The most common
effects observed are signs of toxicity in the liver
and kidney, which are the major detoxifying
organs and the first to show evidence of chronic
disease. 11
These observations are consistently interpreted
by GM proponents and regulators as “not
biologically significant” or as “within the range of
normal variation”, using the spurious arguments
described in Section 3.1.4, above.
3.1.6. Stacked-trait crops are less
rigorously tested than single-trait crops
Most GM crops currently on the market and in
the approvals pipeline are not single-trait crops
but stacked-trait crops. “Stacked-trait” means
that several GM traits are combined in one seed.
For example, GM SmartStax maize has eight GM
traits: six for insect resistance (Bt) and two for
tolerance to different herbicides.
Biotech companies have had to resort to
GMO Myths and Truths 42