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|Section2= |Section7= }} Glyphosate (''N''-(phosphonomethyl)glycine) is a broad-spectrum systemic herbicide used to kill weeds, especially annual broadleaf weeds and grasses known to compete with commercial crops grown around the globe. It was discovered to be a herbicide by Monsanto chemist John E. Franz in 1970. Monsanto brought it to market in the 1970s under the trade name Roundup and Monsanto's last commercially relevant United States patent expired in 2000. Glyphosate was quickly adopted by farmers, even more so when Monsanto introduced glyphosate-resistant Roundup Ready crops, enabling farmers to kill weeds without killing their crops. In 2007, glyphosate was the most used herbicide in the United States agricultural sector, with 180 to 185 million pounds () applied, the second-most used in home and garden with 5 to 8 million pounds () and government applied 13 to 15 million pounds () in industry and commerce.〔United States EPA 2007 Pesticide Market Estimates (Agriculture ), (Home and Garden )〕 Glyphosate's herbicidal mode of action is to inhibit a plant enzyme involved in the synthesis of three aromatic amino acids: tyrosine, tryptophan, and phenylalanine. It is absorbed through foliage, and minimally through roots,〔Sprankle, Paul, W. F. Meggitt, and Donald Penner. "Rapid inactivation of glyphosate in the soil." Weed Science (1975): 224-228.〕〔〔 and transported to growing points. Because of this mode of action, it is only effective on actively growing plants and not effective as a pre-emergence herbicide. An increasing number of crops have been genetically engineered to be tolerant of glyphosate (i.e., Roundup Ready soybean, the first Roundup Ready crop, also created by Monsanto Company) which allow farmers to use glyphosate as a postemergence herbicide against weeds. The development of glyphosate resistance in some weed species is emerging as a costly problem. Weed resistance to glyphosate is a growing problem. While glyphosate and formulations such as Roundup have been approved by regulatory bodies worldwide, concerns about their effects on humans and the environment persist.〔 Many regulatory and scholarly reviews have evaluated the relative toxicity of glyphosate as an herbicide. The German Federal Institute for Risk Assessment toxicology review in 2013, found that "the available data is contradictory and far from being convincing" with regard to correlations between exposure to glyphosate formulations and risk of various cancers, including non-Hodgkin lymphoma (NHL).〔 A meta-analysis published in 2014 identified an increased risk of NHL in workers exposed to glyphosate formulations.〔 In March 2015 the World Health Organization's International Agency for Research on Cancer published a summary of its forthcoming monograph on glyphosate, and classified it as "probably carcinogenic in humans" (category 2A) based on epidemiological studies, animal studies, and ''in vitro'' studies.〔〔 == Discovery == Glyphosate was first synthesized in 1950 by Swiss chemist Henry Martin, who worked for the Swiss company Cilag. The work was never published.〔Dill GM et al. (Glyphosate: Discovery, Development, Applications, and Properties ). Chapter 1 in Glyphosate Resistance in Crops and Weeds: History, Development, and Management, Vijay K. Nandula (Editor). Wiley, September 2010 ISBN 978-0-470-41031-8〕 Stauffer Chemical patented the agent as a chemical chelator in 1964 as it binds and removes minerals such as calcium, magnesium, manganese, copper and zinc.〔(United States Patent 3,160,632 (1964) Stauffer Chemical )〕 Somewhat later, glyphosate was independently discovered at Monsanto in 1970. Monsanto chemists had synthesized about 100 analogs of aminomethylphosphonic acid as potential water-softening agents. Two were found to have weak herbicidal activity, and John E. Franz, a chemist at Monsanto, was asked to try to make analogs with stronger herbicidal activity. Glyphosate was the third analog he made.〔 Glyphosate has been called by experts in herbicides "virtually ideal" due to its broad spectrum and low toxicity to animal life compared with other herbicides.〔Stephen O Duke and Stephen B. Powles (2008) (Glyphosate: a once-in-a-century herbicide: Mini-review. ) Pest Management Science Pest Manag Sci 64:319–325〕〔(Monsanto's John E. Franz Wins 1990 Perkin Medal ) Chem. Eng. News, 1990, 68 (11), pp 29–30 〕〔Pesticide Action Network UK.(Glyphosate fact sheet ) Pesticides News No.33, September 1996, p28-29 PAN-UK says it is "a welcome move away from chemicals which are highly toxic to humans and other non target organisms, and from chemicals which cause direct and lasting damage to the environment" and of course cautions against overuse.〕〔Dr. Kathleen A. Marrs (What is Biology Good For? Controlling Weeds: RoundUp )〕 Franz received the National Medal of Technology in 1987 and the Perkin Medal for Applied Chemistry in 1990 for his discoveries. Franz was inducted into the National Inventor's Hall of Fame in 2007. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「glyphosate」の詳細全文を読む スポンサード リンク
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