Hope Not Hype - Third World Network

72 Hope Not Hype
chemicals that can be toxic (Benachour and Séralini, 2009; Richard et al., 2005). For
example, glyphosate mixed with common adjuvants found in commercial herbicide
formulations caused the death of human umbilical, embryonic and placental cells at much
lower concentrations than glyphosate alone (Benachour and Séralini, 2009).
For embryonic or neonatal cells, POEA [polyethoxylated tallowamine], the major adjuvant
[of Roundup formulations], has the highest toxicity, either by itself or amplified 2-5 times in
combination with G [glyphosate] or AMPA [aminomethylphosphinc acid, the major glyphosate
metabolite]…we demonstrate that AMPA is more toxic than G in human cells, especially on
cell membrane. AMPA is also more stable in soil, in plants, and in food or feed residues, and
more present in wastewater (2-35 ppm) than G [0.1-3 ppm]. It is not toxic alone at these
concentrations in our experiments, but it amplifies G or POEA toxicity in combination. The
synergic toxicity of all of these compounds is now more obvious (Benachour and Séralini,
2009, pp. 103-104).
Commercial herbicides also inhibit non-target enzymes, resulting in other unintended
effects. For example, glyphosate inhibits ferric reductase, resulting in iron deficiencies in
some cropping systems (Ozturk et al., 2008).
Glufosinate-ammonium has toxic effects on soil microbial communities as measured
in microcosms.
[O]ur results suggest that the widespread use of glufosinate may have injurious effects on soil
microorganisms and on their activities. The toxicity exerted by glufosinate induced shifts in
the microbial community structure with apparent long lasting significant effects. Changes in
soil microbial populations can also affect soil functionality, thereby influencing nutrient
turnover and the restoration process of the soil (Pampulha et al., 2007, p. 330).
The commercial formulation also has deleterious effects on non-target organisms
such as insects.
In fields of GLA [glufosinate-ammonium] treated crops, caterpillars may consume a sufficient
amount of leaf tissue to accumulate a lethal dose of GLA. We did not investigate the toxicity
of GLA to earlier caterpillar instars which, being smaller than the 5th instar, may be more
sensitive to GLA. Furthermore, our studies examined only the active ingredient (GLA) and
not its commercial formulation, which contains a surfactant that aids in the penetration of
GLA into the leaf surface. Indeed, studies have shown that GLA-containing products were
more toxic to aquatic organisms than GLA alone. Similarly, GLA formulations applied topically
to mammals were found to be 2.5 times more toxic than GLA alone. The formulated herbicide
may also prove more toxic than GLA alone when ingested or applied topically to caterpillars
(Kutlesa and Caveney, 2001, p. 31).
Moreover, with the rise of herbicide-resistant weeds, which are linked to the growing
use of HT crops and resultant change in weed control approaches, farmers may again turn
to the “replaced” herbicides and tillage (Valverde and Gressel, 2006), and thus negate
these claimed benefits of HT crops to human health and the environment.