Hope Not Hype - Third World Network

Presence
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Unintended risks to human health caused by presence
Not all GMOs in the human food chain may have benefited from a safety evaluation
or been deemed to be safe as food (Table 4.1).
Industry sources estimate that in 2000 in the Saskatchewan region of Canada alone, more
than 300,000 acres of wheat were planted with unregistered or obsolete [GM] plant varieties.
Exports by volume are composed of some varieties that have not been, or are no longer,
approved for release in Canada. Regionally across western Canada, wheat exports contain
0.6-2.4% of these unregistered or obsolete varieties (Smyth et al., 2002, p. 537).
In the 20 years since the USDA started to regulate field tests, it has approved nearly 50,000
field sites. But an internal audit commissioned by the USDA inspector-general and released
on 22 December 2005 was severely critical. The report admonished the agency for lacking
basic information about test sites, failing to inspect field tests sufficiently, and neglecting
the fate of the crops after testing (Ledford, 2007, p. 132).
Even transgenes that have been deemed safe when tested in one genetic background
may not be assumed safe if they are bred by accident or by chance into other genetic
backgrounds of the same species or between species (e.g., by horizontal gene transfer
between GMO microbes).
Once in the agroecosystem, transgenes may not be easily recalled.
[Canada/oilseed rape:] Ten years after a trial of GM herbicide-tolerant oilseed rape, emergent
seedlings were collected and tested for herbicide tolerance. Seedlings that survived the
glufosinate herbicide (15 out of 38 volunteers) tested positive for at least one GM insert.
The resulting density was equivalent to 0.01 plants m -2 , despite complying with volunteer
reduction recommendations (D’Hertefeldt et al., 2008, p. 314).
[France/oilseed rape: GM] seed admixture could still occur in the harvest of [a] conventional
variety 8 years after growing transgenic OSR [oilseed rape]…admixture of transgenic and
conventional seeds in a conventional OSR harvest can occur at a rate as high as 18% in a 5-
year rotation, far above the European threshold [of 0.9%]…Unless appropriate management
and agronomical guidelines to manage volunteers are implemented, it will indeed be hazardous
for a farmer to go back to a conventional non-GM farming system, even 5 years after the last
transgenic OSR harvest (Messéan et al., 2007, p. 121).
[US and global/maize:] Despite a massive recall of food products and extraordinary efforts
to recover StarLink seed, the cry9 transgenes still persisted at detectable levels in US corn
supplies 3 years later. The lingering presence of StarLink demonstrates that once a transgene