Banishing Glyphosate

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Banishing Glyphosate
prostate cancer, cutaneous melanoma (each represented by a single study, reviewed in [10]). No association was found for in
case-control studies for glyphosate exposure and adenocarcinomas of the oesophagus and stomach (one study), glioma (three
studies), or soft tissue sarcoma (one study) as reviewed in [10].
In summary, there is evidence that glyphosate exposure is associated with increased risk of non-Hodgkin’s lymphoma from
several large studies as well as smaller studies. In addition, single studies have found non-significantly increased RRs or ORs for
glyphosate exposure and several cancer sites.
Increase in pesticide burden on health due to glyphosate use with glyphosate tolerant GM crops
Glyphosate contamination ubiquitous in the environment
Glyphosate herbicides have been marketed since the 1970s, but the steep rise in their use began with the commercial release of
GM glyphosate-tolerant crops 30 years ago, and they rapidly become the world’s top selling herbicides. Currently, 85 % of GM
crops planted globally are herbicide-tolerant, with glyphosate-tolerant crops making up the vast majority of those planted [31]. In
the USA, the largest producer of GM crops, 93 % of soybean, 85 % of cotton, and 85 % of maize crops are glyphosate-tolerant [32].
In recent years, the use of glyphosate herbicides has expanded to include weed control in residential and commercial areas and as
desiccant to aid in harvesting a wide range of conventional non-GM crops [33]. The global glyphosate market demand in 2012 was
718 600 tonnes [34], with GM crops accounting for 45.2 % of the total demand, and glyphosate ~25 % of the global pesticide market
[35]. In the USA alone, overall pesticide use increased by an estimated 183 million kilograms (404 million pounds) in the first
16 years of GM crops between 1996 and 2011 [36]; and glyphosate is estimated to account for ~40 % of all pesticide use (by weight
of active ingredient) from figures provided by the US EPA in 2007 [37]. Glyphosate and glyphosate residues have contaminated
the entire environment, air, soil, water, urban, suburban, and rural, representing an enormous increase in the pesticide burden on
global health.
A compilation representing the largest and most comprehensive assessment of the environmental occurrence of glyphosate
and AMPA in the US conducted to-date summarises the results of 3 732 water and sediment and 1 018 quality assurance samples
collected between 2001 and 2010 from 38 states and the District of Columbia [38]. The results indicate that glyphosate and AMPA
are detected frequently together, that they are mobile and occur widely in the environment. Overall, glyphosate was detected in
39.4 % of samples (median < 0.2, maximum 476 mg/L or kg in soil and sediment), and AMPA in 55.0 % (median 0.05, maximum 397
mg/L or kg in ditches and drains). Glyphosate and AMPA were detected frequently in soils and sediment (91.1 % and 93.3 % respectively),
ditches and drains (70.9 % and 80.7 % respectively), precipitation (70.6 % and 71.8 % respectively), rivers (53.1 % and 89,3
% respectively) and streams (52.5 % and 55.0 % respectively, and less frequently in lakes, ponds, and wetlands (33.7 % and 29.8 %
respectively), soil water (34.5 % and 65.5 % respectively, and groundwater (5.8 % and 14.3 % respectively).
Glyphosate builds up and leaches from soil
Glyphosate is a polar amphoteric compound that binds strongly to soils but is also very soluble in water. It has a soil half-life ranging
from 2 to 215 days, and an aquatic half-life of 2 to 91 days. Glyphosate degrades in the environment primarily by microbial
action to AMPA, which is also very water soluble, and degrades more slowly than glyphosate. AMPA has a soil half-life of 60-240
days and an aquatic half-life comparable to that of glyphosate. AMPA ultimately degrades to inorganic phosphate, ammonium
and CO2, adding phosphate pollution to aquatic systems (reviewed in [38]). Recent samplings in Argentina showed glyphosate
levels in rain water averaging 6.5 mg/L and as high as 67 mg/L, more than 20 times the level in the USA. In Spain all 11 groundwater
sites sampled were positive for glyphosate despite it being a region free from glyphosate-tolerant GM crop cultivation (reviewed
in Chapter 1). Thus both glyphosate and its main metabolite AMPA are long-lasting in the environment, and leach easily into
water; this is contrary to claims by the manufacturer, which has been repeatedly prosecuted for false advertising that Roundup
is “biodegradable”, “won’t build up in the soil”, “no leaching”, and “less toxic to rats than table salt”, “‘practically non-toxic’” to
mammals, birds and fish” [39, 40]
Glyphosate bioaccumulates
In the IARC report on glyphosate, it is stated that [10, p. 45]: “Overall, systemically absorbed glyphosate is not metabolized efficiently,
and is mainly excreted unchanged in the urine.” This has been shown to be false, as AMPA has been detected frequently
in human urine, and glyphosate in human mother’s milk and in animal tissues (reviewed in Chapter 1).
A study commissioned by Friends of the Earth Europe analysed 182 volunteers across 18 EU countries found that 80 (43.9 %)
have glyphosate, with a mean of 0.21 mg/L and a maximum of 1.82 mg/L. AMPA was present in 65 (35.71 %), with a mean of 0.18
mg/L and a maximum of 2.63 mg/L. In the US, urine samples show concentrations 8 times those in Europe. The analysis, commissioned
by Moms Across America, also tested 10 mothers’ breast milk, which came up positive for glyphosate with levels ranging
from 76 to 166 µg/L, higher than those in urine, and 760 to 1600 times higher than the European Drinking Water Directive allowed
levels for individual pesticides, falling within the range of concentrations at which developmental toxicity has been observed in
animal studies. A second study on breast milk commissioned by the Green Party was performed in Germany, where far fewer GM
crops are consumed, and glyphosate levels ranged from 0.210-0.432 µg/L, well above the EU drinking water limit of 0.1 µg/L.
In a peer-reviewed study published in 2014 [41], not included in the IARC assessment, glyphosate was detected in human, cow,
rabbit and hare urine as well as in tissues of cows. Samples were collected from Germany (except for urine from Danish cows) as
follows: urine of cows from conventional farms in (N=343), urine from cows kept in GM free areas (N=32); organs from slaughtered
cows from conventional husbandry: gut wall (N=32), liver (N=4), kidney (N=26), lung (N=23) and muscle (N=6); urine from
Danish cows (N = 242); urine from 192 hares and 77 fattening rabbits; human urine from 99 on conventional diet and 41 on organic
diet; and further human urine samples from 102 healthy subjects and 199 chronically ill subject. A two-way analysis of variance
followed by unpaired Student’s t-tests was used to identify significant differences between means. The results are presented in
Figure 1 (unfortunately, the authors chose not to tabulate the numerical values). As can be seen, urine from German cows had on
average significantly less glyphosate than urine from cows in Denmark (p