Glyphosate

Glyphosate (<a href="/facts/IUPAC_name/qIDqTvoI">IUPAC name</a>: N-(phosphonomethyl)glycine) is a broad-spectrum <a href="/facts/Systemic_herbicide/FN93bvrk">systemic herbicide</a> and <a href="/facts/Crop_desiccant/eYRbboIv">crop desiccant</a>. It is an <a href="/facts/Organophosphorus_compound/kNgIF93U">organophosphorus compound</a>, specifically a <a href="/facts/Phosphonate/8mg6nNRP">phosphonate</a>, which acts by <a href="/facts/EPSP_inhibitor/LU5Y1R3b">inhibiting the plant enzyme 5-enolpyruvylshikimate-3-phosphate synthase</a> (EPSP). <a href="/facts/Glyphosate-based_herbicides/8GVXMgt4">Glyphosate-based herbicides</a> (GBHs) are used to kill <a href="/facts/Weed/Dog4Ifol">weeds</a>, especially annual <a href="/facts/Forbs/G6S7e8E6">broadleaf weeds</a> and grasses that compete with <a href="/facts/Crop/JoQKR5R8">crops</a>. Monsanto brought it to market for agricultural use in 1974 under the trade name <a href="/facts/Roundup_(herbicide)/y2AudgdY">Roundup</a>. Monsanto's last commercially relevant United States <a href="/facts/Patent/LjT2bG3A">patent</a> expired in 2000.
Farmers quickly adopted glyphosate for agricultural weed control, especially after Monsanto introduced glyphosate-resistant <a href="/facts/Roundup_Ready_crops/52rPYMrX">Roundup Ready crops</a>, enabling farmers to kill weeds without killing their crops. In 2007, glyphosate was the most used herbicide in the United States' agricultural sector and the second-most used (after <a href="/facts/2%2c4-Dichlorophenoxyacetic_acid/8nQt0CjC">2,4-D</a>) in home and garden, government and industry, and commercial applications. From the late 1970s to 2016, there was a 100-fold increase in the frequency and volume of application of GBHs worldwide, with further increases expected in the future.
Glyphosate is absorbed through foliage, and minimally through roots, and from there translocated to growing points. It inhibits <a href="/facts/EPSP_synthase/LU5Y1R3b">EPSP synthase</a>, a plant enzyme involved in the synthesis of three <a href="/facts/Aromatic_amino_acid/lkh9b0Ax">aromatic amino acids</a>: <a href="/facts/Tyrosine/RJhEgE4C">tyrosine</a>, <a href="/facts/Tryptophan/JcUxlxAh">tryptophan</a>, and <a href="/facts/Phenylalanine/eyojfW7t">phenylalanine</a>. It is therefore effective only on actively growing plants and is not effective as a <a href="/facts/Preemergent_herbicides/LBYgAqD1">pre-emergence herbicide</a>. Crops have been <a href="/facts/Genetic_engineering/vwdlDR61">genetically engineered</a> to be tolerant of glyphosate (e.g. <a href="/facts/Roundup_Ready_soybean/hB4tR5j4">Roundup Ready soybean</a>, the first Roundup Ready crop, also created by Monsanto), which allows farmers to use glyphosate as a post-emergence herbicide against weeds.
While glyphosate and formulations such as Roundup have been approved by regulatory bodies worldwide, concerns about their effects on humans and the environment have persisted. A number of regulatory and scholarly reviews have evaluated the relative toxicity of glyphosate as an herbicide. The WHO and <a href="/facts/Food_and_Agriculture_Organization/13WV8JJK">FAO</a> Joint committee on pesticide residues issued a report in 2016 stating the use of glyphosate formulations does not necessarily constitute a health risk, giving an <a href="/facts/Acceptable_daily_intake/XxKe0NPy">acceptable daily intake</a> limit of 1 milligram per kilogram of body weight per day for chronic toxicity.
The <a href="/facts/Scientific_consensus/DrTWaQIy">consensus</a> among national pesticide regulatory agencies and scientific organizations is that labeled uses of glyphosate have demonstrated no evidence of human carcinogenicity. In March 2015, the <a href="/facts/World_Health_Organization/YNN3bgug">World Health Organization</a>'s <a href="/facts/International_Agency_for_Research_on_Cancer/Pb8KPyTz">International Agency for Research on Cancer</a> (IARC) classified glyphosate as "probably carcinogenic in humans" (<a href="/facts/List_of_IARC_Group_2A_carcinogens/vEpMWjhm">category 2A</a>) based on epidemiological studies, animal studies, and <a href="/facts/In_vitro/evp3hAX6">in vitro</a> studies. In contrast, the <a href="/facts/European_Food_Safety_Authority/wooppnvX">European Food Safety Authority</a> concluded in November 2015 that "the substance is unlikely to be <a href="/facts/Genotoxicity/fRUJaqxo">genotoxic</a> (i.e. damaging to <a href="/facts/DNA/nB89Iauz">DNA</a>) or to pose a <a href="/facts/Carcinogen/soH8Y9CE">carcinogenic</a> threat to humans", later clarifying that while carcinogenic glyphosate-containing formulations may exist, studies that "look solely at the active substance glyphosate do not show this effect". In 2017, the <a href="/facts/European_Chemicals_Agency/5UVljucv">European Chemicals Agency</a> (ECHA) classified glyphosate as causing serious eye damage and as toxic to aquatic life but did not find evidence implicating it as a carcinogen, a mutagen, toxic to reproduction, nor toxic to specific organs.

Glyphosate open-in-new

Glyphosate