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Roundup is the brand name of a systemic, broad-spectrum herbicide produced by the U.S. life sciences giant Monsanto. It is the most used herbicide in the world, and the top-selling agrichemical of all time. Monsanto developed and patented the glyphosate molecule in the 1970s, and marketed Roundup from 1973. It retained exclusive rights in the US until its US patent expired in September, 2000, and maintained a predominant marketshare in countries where the patent expired earlier.

The active ingredient of Roundup is the isopropylamine salt of glyphosate. Glyphosate's mode of action is to inhibit an enzyme involved in the synthesis of the amino acids tyrosine, tryptophan and phenylalanine. It is absorbed through foliage and translocated to growing points. Weeds and grass will generally re-emerge within one to two months after usage. Because of this mode of action, it is only effective on actively growing plants; it is not effective as a pre-emergence herbicide. Due to the absorption being limited to foliage, soil-bound glyphosate is effectively inert. (See main article glyphosate)

Monsanto also produces seeds which grow into plants genetically engineered to be tolerant to glyphosate which are known as Roundup Ready crops. The genes contained in these seeds, although naturally occurring in other species, are patented (See Glyphosate). Such crops allow farmers to use glyphosate as a post-emergence pesticide against both broadleaf and cereal weeds. Soy was the first Roundup Ready crop and was produced at Monsanto's Agracetus Campus located in Middleton, Wisconsin. Current Roundup Ready crops include maize (corn), sorghum, cotton, soy, canola and alfalfa.

The largest single user of Roundup reportedly is the U.S. Government, which sprays huge quantities of the herbicide over the northern countries of South America in an effort to discourage cultivation of the coca plant. (See article Plan Colombia).

Health concerns

The surfactants used in the Roundup products may cause health issues. Like all herbicides, Roundup should only be applied in accordance with all labeling and legal requirements. In repeated dose toxicity testing, Roundup Original RT was found to be mildly irritating to the eyes and not irritating dermally.

The US Environmental Protection Agency, the EC Health and Consumer Protection Directorate, and the UN World Health Organization have all independently concluded that glyphosate is not carcinogenic. Despite this, opponents of glyphosate-based pesticides frequently claim that glyphosate is linked to cancer, citing the research of Hardell and Eriksson (Cancer 1999 85:1353–1360). Although this paper showed a link between glyphosate and lymphoma, this link was not statistically significant and was within the realm of random variation. The authors themselves concluded "definite conclusions cannot be drawn for separate chemicals, such as MCPA and glyphosate, from the multivariate analysis".

Opponents also claim that Roundup has been found to cause genetic damage, citing the research of Peluso et al (Environ Molec Mutag 31:55–59). The authors concluded that the damage was "not related to the active ingredient, the isopropylammonium salt of glyphosate, but to another component of the herbicide mixture".

The toxicity of Roundup has been questioned, not so much because of its active agent (glyphosate) but because of the inactive ingredients, including the surfactant polyoxy-ethyleneamine (POEA) . These components are responsible for "acute" toxicity to humans such as eye irritation. Ingestion of Roundup has been proven to cause diarrhea following extremely high exposures. . Glyphosate was also reported to kill fish at concentrations of 10 parts per million (WHO, UNEP & ILO, 1994).

Roundup has also been found by researchers at Texas Tech University to disrupt the expression of steroidogenic acute regulatory protein (StAR) which has a role in testosterone production in malesand which would affect human fetility and reproduction. .

Effect on animals

Roundup was once believed to have no effect on animals. However, as of 2005, research has shown that, when roundup is applied directly to water in contravention of the product labeling, the surfactant polyethoxylated tallow amine (POEA) can kill tadpoles by interrupting amphibian respiration through their skins. A 1995 Australian study concluded that ‘Roundup’ a popular and supposedly ecofriendly herbicide “was extremely toxic to tadpoles and adult frogs” (The New Zealand Frog Survey).

External links

• Graphic network of Business and political connections for Monsanto
• Roundup website (Monsanto)
• Roundup website (French Website)
• EPA's Integrated Risk Information System entry for Roundup
• EPA's ground & drinking water consumer factsheet for glyphosate
• Greenpeace: A Critique of Monsanto's Risk Evaluation
• Monsanto and the Roundup Ready Controversy
• Greenpeace: Why Consumers and Farmers Should Avoid Monsanto's GE Soybeans
• Greenpeace: Glyphosate and Your Food
• http://www.gene.ch/genet/1999/Jun/msg00012.html
• University of Pittsburgh professor finds herbicide kills frogs (an article from 2005)

References

• Pease W S et al. (1993) Preventing pesticide-related illness in California agriculture: Strategies and priorities. Environmental Health Policy Program Report. Berkeley, CA: University of California. School of Public Health. California Policy Seminar.
• Wang Y, Jaw C and Chen Y (1994) Accumulation of 2,4-D and glyphosate in fish and water hyacinth. Water Air Soil Pollute. 74:397-403
• Baccara, Mariagiovanna, et al. Monsanto's Roundup, NYU Stern School of Business: August 2001, Revised July 14, 2003.

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