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| Green soybeans. CC photo by UD Carvel REC on Flickr |
The phrase has no scientific basis, but
seems to mean “close nutritional and elemental similarity between a genetically
modified (GM) crops and a non-GM traditional counterpart” (Bohn).
Back in the 1990s, the most-planted GM crop so far commercialised, Roundup Ready soya, was pronounced 'substantially equivalent' whether it had been sprayed with Roundup herbicide (the form always on the market) or grown unsprayed (a form only ever found in laboratories).
Despite the hype about how GM crops reduce pesticide use, actual pesticide levels have never been factored into the 'substantial equivalence' assessments. Nor have pesticide levels in GM crops ever been systematically monitored in the US, UK or Canada.
Aware of a glaring knowledge gap regarding
nutrient and elemental qualities, and the pesticide levels, in the GMOs in our
food chain, a team of Norwegian scientists carried out a real-life survey of GM
soya.
To limit environmental influences, they
selected crops within a 200 kilometre
radius in a major soya-growing area in Iowa.
They then compared three types of soya based on its agri-management:
- Roundup Ready soya (10 crops) sprayed with glyphosate (the active herbicidal ingredient of Roundup) and various routine pesticide treatments.
- Conventional soya (10 crops) subject to various routine pesticide treatments.
- Organic soya (11 crops) grown without chemicals
COMMENT
Fertiliser treatments were, presumably, tailored to the individual plot
by the farmer.
The varieties of soya tested represented a
real-life cross section within each category, although there were some
identical strains grown under more than one regime.
Nutrient levels will vary with a crop's
genetic background and with environmental influences. The limited control over both these factors
in this 'real-life' study would be expected to lead to wider variations which
would blur the distinctions between crops under the three agri-management
systems studied.
However, using 35 different nutritional and
elemental variables to characterise each soya sample, the Norwegian scientists
were able to discriminate GM, convention and organic beans, without
exception.
Interestingly, the organic soya showed the
healthiest nutritional profile with more sugars, significantly more total
protein and zinc, less fibre, and less saturated fat and omega-6-fatty-acids
than the GM or conventional beans.
Non-glyphosate pesticide residues were
surprisingly little in evidence: contamination at levels of hundredths of a
milligram per kilogram was found in one GM and one conventional sample;
contamination at a level of thousandths of a milligram per kilogram was found
in one organic sample; trace levels (less than one microgram per kilogram) of
four pesticides were found in all samples, indicating a general background
level of chemical pollution in cropping environments.
Total glyphosate (i.e. glyphosate plus its
major metabolite, 'AMPA') was absent from conventional and organic beans, but
clearly present at levels of up to 15 milligrams per kilogram in all GM samples
(Note that this is four orders of magnitude higher than any other chemical
residue tested). Since Roundup Ready
soya is designed to accumulated glyphosate, its presence was to be expected,
but the levels found were unexpectedly high.
Glyphosate contamination in Roundup Ready
beans (representing 75% of global soya production) was below the 'maximum
residue level' (MRL) of 20 milligrams per kilogram set in most countries. However, the MRL seems to have been fixed in
response to the needs of GM soya producers, rather than with regard to a safety
limit. Recent reports of
endocrine-disrupting [1,2], embryo-damaging [3], and cancer-promoting [2,4]
effects of glyphosate a very low levels of exposure are putting the current MRL
in doubt.
It seems also that regulators have paid
little heed to the effects of time plus the large-scale use of Roundup Ready
crops. Both these factors have shaped
today's real-life soya supply.
Back in 1999, Monsanto claimed that
glyphosate-contamination in Roundup Ready soya was less than that arising in
conventional crops which have been treated with the herbicide as a harvesting
aid. The latter was quoted to be in the
region of 16-17 milligrams per kilogram.
In the same year, Monsanto claimed that a contamination of 5.6
milligrams per kilogram glyphosate found in GM soya represented “extreme
levels, and far higher than those typically found”.
As the current study (14 years on) shows,
glyphosate accumulation in some GM crops is now approaching the levels only
previously seen in pre-harvest treated crops when there has been no time for
dissipation of the herbicide. Also,
seven out of ten GM samples now exceed the previous, untypical, “extreme
level”.
As Roundup-resistant weeds become endemic
in American fields, it seems clear that Roundup Ready crops are being sprayed
with more glyphosate, more often and closer to harvest time as the years go
by. What's entering the food chain now
in soya doesn't seem to be substantially equivalent to conventional soya, nor
to the soya which was originally approved by regulators.
OUR COMMENT
Glyphosate and AMPA are known to be toxic
to plants, reducing photosynthesis and interfering with metal-ion-dependent
physiological processes. As the
contamination increases, is it likely that the GM plants' altered physiology
will produce crops which remain 'substantially equivalent' to
non-glyphosate-treated crops (if they ever were)?
An EU review of glyphosate safety and its
MRL is about to be released. The report
is expected to recommend business as usual and the raising of the MRL from 0.3 mg/kg body-weight/day to 0.5 mg/kg.
New data emerging from up-to-date, more
sophisticated, scientific techniques has been ignored as has the consistent
finding that Roundup formula, which is what we are actually exposed to, is more
toxic than glyphosate.
Next-generation GM crops will be tolerant
to glyphosate plus at least one other herbicide. Safety studies of such future chemical
cocktails are essential, as is monitoring of our exposure to all of
them, and a close watch on how the cocktail is affecting plant nutrient
'equivalence'.
Ask DEFRA and the EU regulators to
reconsider glyphosate safety on the basis all recent studies on Roundup as a matter of urgency.
[1]
ROUNDUP ENDOCRINE DISRUPTOR - March 2012
[2]
GLYPHOSATE AND CANCER - September 2013
[3]
ROUNDUP CAUSES BIRTH-DEFECTS - (Document link) GMFS ARCHIVE - October 2010
[4]
HOW GLYPHOSATE COULD BE LINKED TO CANCER - January 2014
T Bohn, et al, 2014, Compositional differences in soybeans on the market: Glyphosate accumulates in Roundup Ready GM soybeans, Food Chemistry 153
Germany claims no problem
with glyphosate, GM Watch 23.01.14
Christopher Schrader, Controversial
glyphosate poison can be sprayed, Sueddeutsche.de 22.01.14
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