HEALTH EFFECTS OF GLYPHOSATE
The rapid expansion of GM RR soy has led to large increases in the use of glyphosate. It is often claimed that glyphosate is safe for people and the environment. But scientific research challenges these claims.
Studies show that glyphosate has serious toxic effects on health and the environment. The added ingredients or adjuvants in Roundup increase its toxicity. Harmful effects from glyphosate and Roundup have been found even at levels that are commonly used in agriculture and found in the environment.
Findings include: In human cells, Roundup causes total cell death within 24 hours. These effects are found at levels far below those recommended for agricultural use and corresponding to low levels of residues found in food or feed.6 • Glyphosate herbicides are endocrine disruptors (substances that interfere with hormone functioning) in human cells. These effects are found at levels up to 800 times lower than residue levels allowed in some GM crops used for animal feed in the United States. Glyphosate herbicides damage DNA in human cells at these levels.7 • Glyphosate and Roundup adjuvants damage human placental cells in concentrations lower than those found with agricultural use.8 9 10 • Glyphosate and Roundup damage human embryonic cells and placental cells, in concentrations well below those recommended for agricultural use.11 • Roundup is toxic and lethal to amphibians. Applied at the rate recommended by the manufacturer for agricultural use, Roundup caused a 70 per cent decline in the species richness of tadpoles.12 An experiment using lower concentrations still caused 40 per cent mortality.13 • Glyphosate herbicides and glyphosate’s main metabolite (environmental breakdown product), AMPA, alter cell cycle checkpoints in sea urchin embryos by interfering with the physiological DNA repair machinery.14 15 16 17 Such disruption is known to lead to genomic instability and the possible development of human cancers. • Glyphosate is toxic to female rats and causes skeletal malformations in their foetuses.18 • AMPA, the major environmental breakdown product of glyphosate, causes DNA damage in cells.19 These findings show that glyphosate and Roundup are highly toxic to many organisms and to human cells.
New study confirms glyphosate’s link with birth defects
In 2009 Argentine government scientist Professor Andrés Carrasco20 announced his findings that glyphosate herbicide causes malformations in frog and chicken embryos, in doses much lower than those used in agricultural spraying. The malformations were of a similar type to those seen in the offspring of humans exposed to such herbicides.21
Carrasco commented, “The findings in the lab are compatible with malformations observed in humans exposed to glyphosate during pregnancy.” He added that his findings have serious implications for people because the experimental animals share similar developmental mechanisms with humans.22 Carrasco said that most of the safety data on glyphosate herbicides and GM soy were provided by industry and are not independent.
In their study, Carrasco’s team criticized Argentina’s overreliance on glyphosate caused by the expansion of GM RR soy, which in 2009 covered 19 million hectares – over half the cultivated area of the country. They noted that 200 million litres of glyphosate herbicide are used in the country to produce 50 million tons of soybeans per year.23 24
Carrasco said in an interview that people living in soy-producing areas of Argentina began reporting problems in 2002, two years after the first big harvests of GM RR soy. He said, “I suspect the toxicity classification of glyphosate is too low ... in some cases this can be a powerful poison.”25
Carrasco found malformations in frog and chicken embryos injected with 2.03 mg/kg glyphosate. The maximum residue limit allowed in soy in the EU is 20 mg/kg, 10 times higher.26
Argentina: Proposed ban on glyphosate and and court ruling
After the release of Carrasco’s findings, environmental lawyers petitioned the Supreme Court of Argentina to ban glyphosate. But Guillermo Cal, executive director of CASAFE (Argentina’s crop protection trade association), said a ban would mean “we couldn’t do agriculture in Argentina”.27
No national ban was implemented. But in March 2010, a court in Santa Fe province, Argentina upheld a decision blocking farmers from spraying agrochemicals near populated areas.28
Argentina: Chaco provincial government report
In April 2010 a commission opened by the provincial government of Chaco in Argentina completed a report analyzing health statistics in the town of La Leonesa and other areas where soy and rice crops are heavily sprayed.29 The commission reported that the childhood cancer rate tripled in La Leonesa from 2000 to 2009. The rate of birth defects increased nearly fourfold over the entire state of Chaco.
This dramatic increase of disease coincided with the expansion of glyphosate and other agrochemical spraying in the province.
A member of the commission that prepared the study, who asked not to be identified due to the “tremendous pressures” they were under, said, “We don’t know how this will end, as there are many interests involved.”30
Argentina: Sprayed community prevented from hearing glyphosate researcher
There is intense pressure on researchers and residents in Argentina not to speak out about the dangers of glyphosate and other agrochemicals. In August 2010 Amnesty International reported31 an incident in La Leonesa, a town where residents have actively opposed agrochemical spraying. An organized mob violently attacked people who gathered to hear a talk by Professor Andrés Carrasco on his research findings that glyphosate caused malformations in frogs. Three people were seriously injured and the event had to be abandoned. Carrasco and a colleague shut themselves in a car and were surrounded by people making violent threats and beating the car for two hours. Witnesses said they believed the attack was organized by local officials and a rice producer, in order to protect agro-industry interests.
Epidemiological studies on glyphosate
Epidemiological studies on glyphosate exposure show an association with serious health problems, including: • premature births and miscarriages32 • multiple myeloma (a type of cancer)33 • non-Hodgkin’s lymphoma (another type of cancer)34 35 • DNA damage.36
By themselves, these epidemiological findings cannot prove that glyphosate is the causative factor. But the toxicological studies on glyphosate cited above confirm that it poses health risks.
Indirect toxic effects of glyphosate
Glyphosate is marketed as a product that breaks down rapidly and harmlessly in the environment. But this is not true. In soil, glyphosate has a half-life (the length of time it takes to lose half its biological activity) of between 3 and 215 days.37 38 In water, glyphosate’s half-life is 35–63 days.39 Glyphosate reduces bird populations40 and is toxic to earthworms.41 42 Claims of the environmental safety of Roundup have been overturned in court in New York43 and France.44