Glyphosate ( N - (phosphonomethyl) glycine) is a broad-spectrum systemic herbicide and crop desiccant. It is an organophosphorus compound, especially phosphonate. It is used to kill weeds, especially the annual broadleaf weeds and grasses that compete with plants. Discovered as a herbicide by Monsanto chemist John E. Franz in 1970. Monsanto took him to the market for agricultural use in 1974 under the trade name Roundup , and the most recently commercially relevant United States patent in the United States ended 2000.
Farmers quickly adopted glyphosate, especially after Monsanto introduced the glyphosate-resistant Roundup Ready plant, allowing farmers to kill weeds without killing their crops. In 2007, glyphosate was the most widely used herbicide in the US agricultural sector and the second most widely used in home and garden (2,4-D most widely used), government and industry, and trade. By 2016 there was a 100-fold increase from the late 1970s in the application frequency and the volume of applied glyphosate-based herbicides (GBHs), with further expected increases in the future, in part in response to the global emergence and spread of glyphosate- hold.
Glyphosate is absorbed through the leaves, and minimally through the roots, and transported to the growing point. This inhibits plant enzymes involved in the synthesis of three aromatic amino acids: tyrosine, tryptophan, and phenylalanine. Therefore, it is effective only on plants that are actively growing and ineffective as a pre-emerging herbicide. An increase in the number of plants has been genetically engineered for glyphosate tolerance (eg Roundup Ready soybeans, the first Roundup Ready plant, also made by Monsanto) that allows farmers to use glyphosate as a post-operative herbicide against weeds. The development of glyphosate resistance in weed species appears as an expensive problem.
While glyphosate and formulations such as Roundup have been approved by regulators around the world, concerns about their effects on humans and the environment remain, and have grown as global use of glyphosate has increased. A number of regulatory and scientific reviews have evaluated the relative toxicity of glyphosate as herbicides. The German Federal Agency for Risk Assessment toxicology assessment in 2013 found that "the available data are contradictory and far from convincing" relates to the correlation between exposure to glyphosate formulations and the risk of various cancers, including non-Hodgkin's lymphoma (NHL). A meta-analysis published in 2014 identifies an increased risk of NHL in workers exposed to glyphosate formulation.
In March 2015 the International Agency for the Organization for International Cancer Research classifies glyphosate as "probably carcinogenic in humans" (category 2A) based on epidemiological studies, animal studies, and in vitro studies . In November 2015, the European Food Safety Authority concluded that "it is not possible to be genotoxic (that is to destroy DNA) or cause carcinogenic threats in humans," later clarifying that while glyphosate-containing formulations containing carcinogenicity may be present, eyes on glyphosate active substances do not show this effect. "The WHO and FAO joint committee on pesticide residues issued a report in 2016 stating the use of glyphosate formulations is not always a health risk, and provides an acceptable daily maximum limit (one milligram/kg weight body per day) for chronic toxicity. The European Chemicals Agency (ECHA) classifies glyphosate as a cause of serious and toxic eye damage to aquatic life, but found no evidence to imply it as carcinogen, mutagen, toxic to reproduction, or toxic to certain organs.
To add to the confusion in the public mind, a major US Department of Health study released results in November 2017 that showed a lack of correlation with any form of cancer. The study of 90,000 family members of farmers for more than 23 years strongly presupposes the lack of chronic toxicity of commercial formulations used in the US.
Video Glyphosate
Discovery
Glyphosate was first synthesized in 1950 by Swiss chemist Henry Martin, who worked for the Swiss company, Cilag. The work was never published. Stauffer Chemical patented the agent as a chemical chelator in 1964 for binding and removing minerals such as calcium, magnesium, manganese, copper, and zinc.
Long ago, glyphosate was independently discovered in the United States at Monsanto in 1970. Monsanto chemists have synthesized about 100 aminomethylphosphonate acid derivatives as potential water softener agents. Two were found to have weak herbicidal activity, and John E. Franz, a chemist at Monsanto, was asked to try to make analogous to the more potent herbicidal activity. Glyphosate is the third analog that it makes. Franz received the US National Technology Medal in 1987 and Perkin Medal for Applied Chemistry in 1990 for his discovery.
Monsanto developed and patented the use of glyphosate to kill weeds in the early 1970s and first brought them to market in 1974, under the brand name Roundup. While the patent originally ended in 1991, Monsanto retained an exclusive right in the United States until its patent on isopropylamine salts expired in September 2000.
In 2008, US Department of Agriculture (USDA) Agricultural Research Service (ARS) scientist Stephen O. Duke and Stephen B. Powles - an Australian weed expert - described glyphosate as an "almost ideal" herbicide. In 2010, Powles stated: "Glyphosate is one in 100-year-old discovery that is equally important for reliable global food production because penicillin is to fight disease."
In April 2017, the Canadian government declared that glyphosate was "Canada's most used herbicide", in which the product label date was revised to ensure a 20% POEA by weight limit.
Maps Glyphosate
Chemistry
Glyphosate is an aminophosphate analogue of natural amino acid glycine, and like all amino acids, it exists in various ionic states depending on the pH. Both the phosphonic acid and the carboxylic acid group can be ionized and the amine group can be protonated and the substance exists as a series of zwitter. Glyphosate dissolves in water up to 12 g/l at room temperature. The original synthetic approach to glyphosate involves the reaction of phosphorus trichloride with formaldehyde followed by hydrolysis to produce phosphonate. Glycine is then reacted with this phosphonate to produce glyphosate, and its name is taken as the contraction of the compound used in this synthesis - that is. gly cine and phos phos meal .
- PCl 3 H 2 CO -> Cl 2 P (= O) -CH 2 Cl Cl 2 H 2 O -> (HO) 2 sub> P (= O) -CH 2 Cl 2 HCl
The major deactivation pathway for glyphosate is hydrolysis to aminomethylphosphonic acid.
Industrial synthesis
Two major approaches are used to synthesize glyphosate industrially. The first is an iminodiacetic acid reacting with phosphoric acid and hydrochloric acid (sometimes formed in situ) with the addition of phosphorus trichloride) through a modified Mannich reaction. The oxidation then leads to the desired glyphosate product. Iminodiacetic acid is usually prepared in place, such as by the reaction of chloroacetic acid with ammonia and calcium hydroxide to produce calcium iminodiasetate salt and then acidification of the product.
The chloroacetic acid approach is less efficient than other iminodiacetic acid approaches, due to the production of calcium chloride waste and yield reduction. When hydrogen cyanide is available as a by-product (say), the alternative approach is to use iminodiacetonitrile, HN (CH 2 CN) 2 , and diethanolamine is also a suitable starting material.
The second involves the use of dimethyl phosphite in the synthesis of one pot. Glycine and paraformaldehyde are reacted in an appropriate organic solvent (usually triethylamine and methanol) to produce bishidroxymethylglycine, (HOCH 2 ) 2 NCH 2 COOH. Dimethyl phosphite is then introduced and acts with hydrochloric acid to bypass the hydroxymethyl group from the nitrogen atom while heating accelerates the hydrolysis of the ester phosphate bond.
This synthetic approach is responsible for most of glyphosate production in China, with considerable work after recycling triethylamine and methanol. Progress has also been made in an attempt to eliminate the need for triethylamine.
Action mode
Glyphosate kills plants by interfering with the synthesis of aromatic amino acids phenylalanine, tyrosine, and tryptophan in the shikimate pathway. This is done by inhibiting enzyme 5-enolpyruvylshikimate-3-phosphate synthase ( EPSPS ), which catalyzes the reaction of shikimate-3-phosphate (S3P) and phosphoenolpyruvate to form 5-enolpyruvyl-shikimate-3-phosphate ( EPSP). Glyphosate is absorbed through the foliage and minimally through the roots, which means it is only effective in actively growing plants and can not prevent seeds from germinating. After application, glyphosate is easily transported around the plant to grow roots and leaves and this systemic activity is essential for its effectiveness. Inhibiting enzymes causes shikimate to accumulate in plant tissues and divert energy and resources from other processes. While growth stops within hours of application, it may take several days before the leaves begin to turn yellow.
EPSP is then dephosphorylated into chorismate, an important precursor to the above-mentioned amino acids. These amino acids are used in protein synthesis and produce secondary metabolites such as folate, ubiquinones, and naphthoquinone.
Studies of glyphosate X-ray crystallography and EPSPS show that the function of glyphosate by occupying the binding site of phosphoenolpyruvate, mimics the intermediate state of the ternary-substrate complex. Glyphosate inhibits the enzyme EPSPS from various plant species and microbes at different levels.
EPSPS is only produced by plants and microbes; the genes that encode it do not exist in the mammalian genome.
Environmental fate
Glyphosate absorbs greatly into the soil, and residues are expected to generally not move in the ground. Land and surface water pollution is limited. Glyphosate is easily degraded by soil microbes to aminomethylphosphonic acid (AMPA, which like glyphosate is highly absorbent to soil solids and thus impossible to leak into groundwater). Although both glyphosate and AMPA are commonly detected in water bodies, a portion of the AMPA detected may actually result from detergent degradation rather than from glyphosate. Glyphosate has the potential to contaminate surface water due to aquatic and erosive use patterns, because it adsorbs suspended soil particles in runoff. The mechanism of glyphosate uptake to the soil is similar to phosphate fertilizers, a presence that can reduce glyphosate uptake. Phosphate fertilizers can be released from the sediment into water bodies under anaerobic conditions, and similar release may also occur with glyphosate, although significant effects of glyphosate release from sediment have not been established. Limited leaching can occur after high rainfall after application. If glyphosate reaches surface water, it is not readily biodegradable by water or sunlight.
The half-life of glyphosate in the soil ranges between 2 and 197 days; typical field half-life of 47 days has been suggested. Soil and climatic conditions affect the persistence of glyphosate in the soil. Median half-lives of glyphosate in water vary from a few to 91 days. At a Texas site, the half-life is only three days. A site in Iowa has a half-life of 141 days. AMPA's glyphosate metabolism has been found in Swedish forest land for up to two years after glyphosate applications. In this case, AMPA's persistence is associated with land that has been frozen for most of the year. Adsorption of glyphosate to the soil, and then loose from the soil, varies depending on the soil type. Glyphosate is generally less persistent in water than in the soil, with persistence of 12 to 60 days observed in Canadian ponds, although persistence of more than one year has been recorded in American pool sediments. The half-life of glyphosate in water is between 12 days and 10 weeks.
According to the fact sheet of the National Pesticide Information Center, glyphosate is not included in the compounds tested by the Pesticide and Food Pesticide Monitoring Program, or in the US Department of Agriculture's Pesticide Data Program. However, field trials show that lettuce, carrots, and barley contain glyphosate residues up to one year after the soil is treated with 3.71 pounds of glyphosate per acre (4.15 kg per hectare). The US has determined an acceptable daily glyphosate intake of 1.75 milligrams per kilogram of body weight per day (mg/kg/bw/day) while the EU has set it 0.3.
Use
Glyphosate is effective in killing a variety of plants, including grass and broadleaf and woody plants. According to volume, this is one of the most widely used herbicides. In 2007, glyphosate was the most widely used herbicide in the US agricultural sector, with 180 to 185 million pounds (82,000 to 84,000 tonnes) used, the second most used in homes and gardens with 5 to 8 million pounds (2,300 up 3,600 tons). ) and the government implements 13 to 15 million pounds (5,900 to 6,800 tonnes) in industry and trade. It is commonly used for agriculture, horticulture, wine preservation, and silviculture purposes, as well as garden maintenance (including home use). This has a relatively small effect on some species of clover and morning glory.
Glyphosate and related herbicides are often used in the eradication of invasive species and habitat restorations, particularly to enhance the formation of native plants in grassland ecosystems. Controlled applications are usually combined with selective herbicides and traditional methods of eradication of weeds such as mulch to achieve optimum effect.
In many cities, glyphosate is sprayed along sidewalks and streets, and gaps between sidewalks where weeds often grow. However, up to 24% of glyphosate applied to hard surfaces can be released by water. Contamination of surface water glyphosate is associated with urban and agricultural use. Glyphosate is used to clean the railroads and get rid of unwanted aquatic vegetation. Since 1994, glyphosate has been used in air spraying in Colombia in coca eradication programs; Colombia announced in May 2015 that in October, it will stop using glyphosate in these programs due to concerns about human toxicity to chemicals.
In addition to being used as herbicides, glyphosate is also used for siccation to improve yields, and as a result of drying, to increase the concentration of sucrose in sugar cane before harvest. The application of glyphosate just before harvest on grains (such as wheat, barley, and wheat) kills food crops so that it dries more quickly and evenly, similar to the use of dessicants. These dried plants should not be aerated (plowed and dried) before they are harvested but can be easily cut straight and harvested. This saves farmers time and money, which is important in the northern region where the planting season is short. Excess residue levels on the seeds produced from the wrong application can cause the plant to not be sold.
In 2003 Monsanto patented the use of glyphosate as an antiparasite, and in 2017 they marketed a Roundup formulation without glyphosate, as a grass herbicide.
Genetically modified plants
Some micro-organisms have a 5-enolpyruvoyl-shikimate-3-phosphate synthetase (EPSPS) version that is resistant to glyphosate inhibition. A version of the glyphosate-resistant enzyme and it is still efficient enough to encourage sufficient plant growth has been identified by Monsanto scientists after much trial and error in the Agrobacterium strain called CP4, which is found to survive. in the waste-fed column at the glyphosate production facility. The CP4 EPSPS gene is cloned and transfected into soy. In 1996, genetically engineered soybeans were made commercially available. Current glyphosate resistant plants include soybeans, corn (maize), canola, alfalfa, beet sugar, and cotton, with wheat still under development.
By 2015, 89% of maize, 94% soybeans, and 89% of cotton produced in the United States are genetically modified to be herbicide tolerant.
Formulations and trade names
Glyphosate is marketed in the United States and around the world by many agrochemical companies, in the strength of different solutions and with various adjuvants, under dozens of trade names. In 2010, more than 750 glyphosate products were on the market. In 2012, in terms of volume about half of global consumption of glyphosate is for agricultural crops; the forestry sector is another important market. Asia and the Pacific are the largest and fastest growing regional markets. Chinese producers collectively are the largest glyphosate and precursor producers in the world and account for about 30% of global exports. Major manufacturers include Anhui Huaxing Chemical Industry Company, BASF, Bayer CropScience, Dow AgroSciences, DuPont, Jiangsu Good Harvest-Weien Agrochemical Company, Monsanto, Nantong Jiangshan Agrochemical & amp; Chemicals Co., Nufarm Limited, SinoHarvest, Syngenta, and Zhejiang Xinan Chemical Industrial Group Company.
Glyphosate is an acidic molecule, so it is formulated as a salt for packaging and handling. Various salt formulations include isopropylamine, diammonium, monoammonium, or potassium as counterion. Monsanto herbicide active ingredient is isopropylamine salt of glyphosate. Another important ingredient in some formulations is the polyethoxylated tallow amine surfactant. Some brands include more than one salt. Some companies report their product as equivalent acid (ae) glyphosate acid, or some report it as an active ingredient (ai) glyphosate plus salt, and others report both. To compare the performance of different formulations, knowledge of how the product is formulated is required. Given that different salts have different weights, the acid equivalent is a more accurate method of expressing and comparing concentrations.
The adjuvant loading refers to the amount of adjuvant already added to the glyphosate product. The full product contains all necessary adjuvants, including surfactants; some do not contain an adjuvant system, while other products contain little adjuvant (minimal or partial loading) and additional surfactants must be added to the spray tank prior to application. In 2000 (just before the Monsanto patent in glyphosate ended), over 400 commercial adjuvants from over 34 different companies are available for use in commercial farming.
The products are supplied most commonly in formulations of 120, 240, 360, 480, and 680 g/l of active ingredients. The most common formulation in agriculture is 360 g/l, either alone or with additional cationic surfactants.
For 360 g/l formulations, European regulations allow applications of up to 12 l/ha to control perennial weeds such as sofa grass. More generally, a rate of 3 l/ha is practiced to control the annual weeds among plants.
Toxicity
Glyphosate is the active ingredient in the herbicidal formulation containing it. However, in addition to glyphosate salts, commercial formulations of glyphosate contain additives, known as adjuvants, such as surfactants that vary in nature and concentration. Surfactants like these are wetting agents that are also used in shampoos, toothpastes, and foods. Surfactants such as talloamine are added to glyphosate to allow it to wet the leaves and penetrate the cuticle.
Many of the common herbicide suspicions revolve around the confusion between a valid statement of acute toxicity as opposed to the same statement of a lack of chronic toxicity at the recommended level of use. For example, while glyphosate formulations with adjuvant talloamine are highly toxic, their use is found to be uncorrelated with health problems such as cancer in the Ministry of Health's large-scale research on 90,000 family members of farmers for more than 23 years.
Glyphosate only
Man
There is limited evidence that the risk of cancer in humans may increase as a result of massive exposure to glyphosate, but there is no good evidence of such risks from typical use, such as domestic gardening. A review article in 2014 reported a significant association between B-cell lymphoma and glyphosate work exposure. In March 2015, the International Agency for International Cancer Research classified glyphosate as "possibly carcinogenic in humans" (category 2A) based on epidemiological studies, animal studies, and in vitro studies . However, in 2016, a joint meeting of the United Nations Experts Panel on Pesticide Residues in Food and Environment and the World Health Organization's Core Assessment Group on Pesticide Residues reported that studies conducted on mammalian animal models show that glyphosate applications oral at doses as high as 2000 mg/kg were not "associated with genotoxic effects in the majority of studies", and that glyphosate was "unlikely to be genotoxic to anticipated dietary exposure". It also reported that glyphosate is unlikely to be carcinogenic in rodents and concluded that glyphosate "is unlikely to pose a carcinogenic risk in humans" from dietary exposure. In September 2016, a systematic review sponsored by Monsanto found no support for a causal relationship between glyphosate exposure and risk of non-Hodgkins lymphoma or multiple myeloma.
Other mammals
Among mammals, glyphosate is considered to have "low to very low toxicity". LD 50 glyphosate is 5,000 mg/kg for mice, 10,000 mg/kg in mice and 3,530 mg/kg in goats. Acute dermal LD ​​ 50 in rabbits greater than 2,000 mg/kg. Indications of glyphosate toxicity in animals usually appear within 30 to 120 minutes after a sizable dose of consumption, and include early stimulation and tachycardia, ataxia, depression, and bradycardia, although severe toxicity may develop into collapse and seizures.
A review of an unpublished short-term rabbit feeding study reported severe toxicity effects at 150 mg/kg/day and "no adverse effects were observed" ranging from 50 to 200 mg/kg/day. Glyphosate can have a carcinogenic effect on nonhuman mammals. These included positive trend induction in the incidence of renal tubular carcinoma and haemangiosarcoma in male rats, and an increase in pancreatic islet cell adenoma in male rats.
In studies of reproductive toxicity performed on rats and rabbits, no maternal or hereditary effects were seen at doses below 175-293 mg/kg body weight per day.
Glyphosate-based herbicides can cause life-threatening arrhythmias in mammals. The evidence also shows that the herbicide causes direct electrophysiological changes in the cardiovascular system of rats and rabbits.
Aquatic aquarium
In freshwater invertebrates (non-specific species), glyphosate has LC 48 hours 50 ranging from 55 to 780 ppm. The 96-hour LC 50 is 281 ppm for the grass prawns ( Palaemonetas vulgaris ) and 934 ppm for the fiddler crab ( Uca pagilator ). These values ​​make glyphosate "a bit toxic to almost non-toxic".
Antimicrobial activity
Antimicrobial activity of glyphosate has been described in the microbiological literature since its discovery in 1970 and a description of the mechanism of action of glyphosate in 1972. The efficacy is described for various bacteria and fungi. Glyphosate can control the growth of apicomplexan parasites, such as Toxoplasma gondii , Plasmodium falciparum (malaria), and Cryptosporidium parvum , and has been considered an antimicrobial agent in mammals. Inhibition may occur with some species of Rhizobium that are important for soy nitrogen fixation, especially under the pressure of moisture.
Soil biota
When glyphosate is in contact with the soil, it can bind to soil particles, thereby slowing down its degradation. Glyphosate and its degradation products, aminomethylphosphonic acid is considered much more benign toxicologically and environmentally than most herbicides are replaced by glyphosate. Meta-analysis 2016 concludes that at the typical application level of glyphosate has no effect on biomass or soil microbial respiration. A 2016 review notes that the effect of glyphosate contrast on earthworms has been found in different experiments with some unaffected species, but others lose weight or avoid treated soil. Further research is needed to determine the impact of glyphosate on earthworms in complex ecosystems.
glyphosate-based formulation
Glyphosate-based formulations may contain a number of adjuvants, identities considered to be trade secrets. Surfactants are used in herbicidal formulations as wetting agents, to maximize coverage and help penetrate herbicides through plant leaves. As an agricultural spray adjuvant, surfactants can be mixed into commercial formulations, such as Roundup, or they can be purchased separately and mixed in place (tank mix).
Polyethoxylated tallow amine (POEA) is a surfactant used in the original Roundup formulation and is generally used in 2015. Different versions of Roundup have included different POEA percentages. The 1997 US government report says that the Roundup 15% POEA while the Roundup Pro 14.5%. A review of the literature given to the EPA in 1997 found that POEA is more toxic to fish than glyphosate. POEA is more toxic to fish and amphibians than glyphosate alone. A 2000 review of ecotoxicological data in Roundup showed there were at least 58 studies on the effects of Roundup on various organisms. This review concludes, "... for terrestrial use an acute and chronic minimal risk Roundup is forecast for potentially exposed organisms."
Man
Acute toxicity and chronic toxicity are associated with dosage. Skin exposure to ready-to-use glyphosate formulations can cause irritation, and photocontamination dermatitis is sometimes reported. This effect may be due to preservatives of benzysothiazolin-3-one. Severe skin burns are very rare. Inhalation is a small route of exposure, but a spray mist can cause mouth or nose discomfort, bad taste in the mouth, or tingling and irritation in the throat. Eye exposure may cause mild conjunctivitis. Superficial corneal injury may occur if irrigation is delayed or inadequate. Death has been reported after a deliberate overdose. Swallowing Roundup that ranges from 85 to 200 ml (from 41% solution) has caused death within hours of ingestion, although it has been swallowed in large amounts of 500 ml with only mild or moderate symptoms. Consumption of more than 85 ml of concentrated products tends to cause serious symptoms in adults including burns due to corrosive effects as well as kidney and liver damage. More severe cases cause "respiratory distress, impaired consciousness, pulmonary edema, infiltration of chest X-ray, shock, arrhythmia, renal failure requiring haemodialysis, metabolic acidosis, and hyperkalemia" and death is often preceded by bradycardia and ventricular arrhythmias.
A 2000 review concluded that "under present conditions and expectations of new uses, there is no potential for Roundup herbicides to pose a health risk to humans". A 2002 review by the EU reached the same conclusion.
A 2012 meta-analysis of all epidemiological studies on exposure to glyphosate formulations found no correlation with any type of cancer. A systematic review of 2013 by the German Institute for Risk Assessment of epidemiological studies of workers using pesticides, exposed to glyphosate formulations found no significant risk, stating that "the available data are contradictory and far from convincing". However, a 2014 meta-analysis of the same study found a correlation between occupational exposure to glyphosate formulation and an increased risk of B-cell lymphoma, the most common type of non-Hodgkin's lymphoma. Workers exposed to glyphosate are twice as likely to acquire B cell lymphoma. A systematic review of observational studies by 2015 found no evidence that exposure to glyphosate in pregnant women causes adverse developmental outcomes in their children. A systematic review and meta-analysis 2016 found limited and weak evidence of a link between glyphosate exposure and risk of non-Hodgkin's lymphoma and multiple myeloma, while no association was found between glyphosate and other lymphohematopoietic cancer risk. The same study notes that the positive associations found may be due to bias and assimilation.
Aquatic aquifers
Monsanto and other companies produce glyphosate products with alternative surfactants specially formulated for aquatic uses, such as Monsanto "Biactive" and "AquaMaster" products. Glyphosate formulations are much more toxic to amphibians and fish than glyphosate alone. POEA half-life (21-42 days) is longer than that for glyphosate (7-14 days) in the aquatic environment.
Some researchers have suggested the effects of pesticide toxicity on amphibians may differ from other water fauna because of their lifestyle; amphibians may be more susceptible to the toxic effects of pesticides because they prefer to breed in shallow, tapering, or ephemeral ponds. This habitat is not always a formal water body and can contain higher pesticide concentrations than larger bodies of water. Studies in various amphibians have demonstrated the toxicity of GBFs containing POEA to amphibian larvae. These effects include disturbances with gill morphology and mortality from either loss of osmotic stability or asphyxia. At sub-lethal concentrations, POEA or glyphosate/POEA formulations have been associated with delayed development, developmental acceleration, diminished size in metamorphosis, development of malformations in the tail, mouth, eyes and head, histological indications of intersex and oxidative stress symptoms.. Glyphosate-based formulations can cause oxidative stress in bullfrog tadpoles.
A 2003 study of various glyphosate formulations was found, "risk assessment based on estimates and measured glyphosate concentrations that would result from their use to control undesirable plants in wetlands and on water suggests that the risk to aquatic organisms is negligible or small at the application level less than 4 kg/ha and only slightly larger at the application rate of 8 kg/ha. "
A meta-analysis 2013 reviewing available data is related to the potential impact of glyphosate-based herbicides on amphibians. According to the authors, the use of glyphosate-based pesticides can not be considered a major cause of amphibian decline, most of which occur before the widespread use of glyphosate or in pure tropical regions with minimal glyphosate exposure. The authors recommend further research on chronic toxicity of species and developmental stages, the level of environmental glyphosate, and relevant sustainable data analysis to determine whether the role of glyphosate may play in amphibian decline worldwide, and suggests including amphibians in standard battery tests.
Effects on plant health
Correlation was found between increased levels of wheat infections by Fusarium and glyphosate application, but "because of the nature of this study, we were unable to determine whether the relationship between the previous GF (glyphosate formulation) was used and the development of FHB was the cause impact ". Other studies have found a causal relationship between glyphosate and decreased disease resistance. Glyphosate exposure has been shown to change the composition of endophytic bacterial species in plant hosts, which vary widely.
Endocrine disorders
In 2007, the EPA selected glyphosate for further screening through the Endocrine Disruptor Screening Program (EDSP). Selection for this program is based on the prevalence of the use of the compound and does not imply a particular suspicion of endocrine activity. On June 29, 2015, the EPA released the Weight of Proof of Conclusion from the Tier 1 EDSP screening for glyphosate, recommending that glyphosate be not considered for Tier 2 testing. Conclusion Weight of Providence states "... there is no convincing evidence of potential interactions with the estrogen pathway, androgen or thyroid. "
Genetic damage
Some studies have not found mutagenic effects, so glyphosate has not been registered with the US Environmental Protection Agency or the International Agency for Research on Cancer databases. Various other studies have shown that glyphosate may be mutagenic. The IARC monograph notes that glyphosate-based formulations can lead to the breaking of DNA strands in various animal taxa in vitro
Government and organization positions
European Food Safety Authority
A systematic review of 2013 by the German Institute for Risk Assessment (BfR) examined over 1,000 epidemiological studies, animal studies, and in vitro studies . It was found that "no classification and labeling for carcinogenicity is justified" and does not recommend the classification of either 1A or 1B carcinogens. This gives a review to EFSA in January 2014 which published it in December 2014. In November 2015, EFSA published its conclusions in the Renewal Assessment Report (RAR), stating that "it is unlikely to pose a carcinogenic hazard to humans". The European Union will mostly be notified by this report when making a decision on the use of glyphosate in November 2017.
The EFSA's decision and the BfR report were criticized in an open letter published by 96 scientists in November 2015 stating that the BfR report failed to adhere to the accepted scientific principles of open and transparent procedures. The BfR report includes unpublished data, no authorship, omitted references, and does not disclose conflict of interest information.
On April 4, 2016, Dr. Vytenis Andriukaitis, European Commissioner for Health and Food Safety, wrote an open letter to the Chairman of the Glyphosate Task Force in Monsanto Europe requesting to publish the full study given to EFSA.
In September 2017, The Guardian reported that part of the Updates Assessment Report prepared by BfR and used by Efsa was copied from a study conducted by Monsanto. Some parts of the copy contain small changes such as using English spelling rather than American forms, but others are copied word by word, including most of the peer reviewed papers used in the report. The Guardian reports that "a spokesman for Monsanto said that Efsa allows update reports to be written in this way because of the large number of toxicological research proposed."
US Environmental Protection Agency
In a 1993 review, the EPA, considered glyphosate to be non-carcinogenic and a relatively low acute toxicity of skin and mouth. EPA is regarded as the "worst" risk model of a person who eats a lifetime of food originating entirely from the sprayed areas of glyphosate with residuals at their maximum level. This model shows that no adverse health effects are expected under these conditions. By 2015, the EPA initiated a review of glyphosate toxicity and by 2016 reported that glyphosate may not be carcinogenic.
International Agency for Research on Cancer
In March 2015, the International Agency for Cancer Research published an upcoming monographic summary of glyphosate, and classified glyphosate as "probably carcinogenic in humans" (category 2A) based on epidemiological studies, animal studies, and in vitro > study. He notes that there is "limited evidence" about human carcinogenicity for non-Hodgkin's lymphoma. The IARC classifies the substance for their carcinogenic potential, and "some positive findings can be sufficient to suggest hazards, even if there are negative studies, as well." Unlike the BfR, it does not perform risk assessments, weighing the benefits against risks.
The BfR responded that the IARC only reviewed the choices of what they had reviewed earlier, and argued that other studies, including a cohort study called Agricultural Health Studies , did not support the classification. The IARC report does not include unpublished industry-funded studies, including those completed by IARC panel leader Aaron Blair, who stated that agency policy requires him not to consider this research. The agency's international protocols state that only published research is used in the classification of carcinogenicity, since national regulatory agencies including the EPA have allowed agrochemical companies to conduct their unpublished research, which may be biased in favor of their profit motives. Monsanto called the IARC report biased and said it wanted it to be withdrawn.
The 2017 review conducted by personnel from EFSA and BfR argues that the difference between the IARC and EFSA conclusions regarding glyphosate and cancer is due to differences in their evaluation of available evidence. This review concludes that "Two assessments of complementary exposures... show that actual exposure levels fall under" reference values ​​identified by EFSA "and do not represent public attention." In contrast, the 2016 analysis concludes that at EFSA's Renewal Assessment Report , "virtually no weight was given for published literature studies and excessive dependence on industry-provided studies that were not publicly available using a series of tests limited to determine the minimum required data for pesticide marketing ", arguing that the IARC's evaluation of may be carcinogenic in humans " accurately reflects the results of published scientific literature on glyphosate. "
In 2017, internal documents from Monsanto are published by lawyers pursuing litigation against the company. The documents indicate that Monsanto has planned public relations efforts to discredit the IARC report, and that the opinion section in Forbes Magazine [i] challenged the report has been written by an author involved by Monsanto who has not disclosed the connection. In response, Forbes deleted it.
California California Office Environmental Health Hazards Rating
After the California Office of Environmental Health Hazard Assessment (OEHHA) announced, in March 2015, plans to have glyphosate listed as a known carcinogen based on the IARC assessment, Monsanto started a case against OEHHA and its director, Lauren Zeise, in 2016, but lost lawsuit in March 2017.
Glyphosate is listed as "known to the State of California causing cancer" by 2017.
European Chemical Agency
On March 15, 2017 the European Chemicals Agency (ECHA) announced ongoing recommendations of the glyphosate risk assessment conducted by the ECHA Risk Assessment Committee (RAC). Their recommendations maintain the current classification of glyphosate as a substance that causes serious eye damage and as a toxic substance for aquatic life. However, RAC found no evidence to imply glyphosate as a carcinogen, mutagen, as toxic to reproduction, and also non-toxic to certain organs.
Usage effects
The emergence of weeds
In the 1990s, when the first genetically engineered crops - such as glyphosate - resistant corn, canola, soybeans and cotton - were introduced, no glyphosate - resistant weeds were known to exist. By 2014, glyphosate-resistant weeds dominate herbicide resistance research. At that time, 23 glyphosate-resistant species were found in 18 countries.
"Resistance evolved after weed populations had experienced intense selection pressures in the form of repeated use of single herbicides." Herbicidal weeds are called 'super weed b * .
According to Ian Heap, a weed specialist, who completed his PhD on resistance to several herbicides in the annual ryegrass (Lolium rigidum) in 1988 - the first case of herbicide-resistant weed in Australia-in 2014 Lolium rigidum is the world's "worst herbicide-resistant weed" with examples in "12 countries, 11 action sites, 9 pruning regimens" and affecting more than 2 million hectares Annual ryegrass is known to be resistant to herbicides since 1982. in 1996, the first documented case of glyphosate resistant L. rigidum was reported in Australia in 1996 near Orange, New South Wales.In 2006, the peasant association reported 107 weed biotypes in 63 weed species with resistance herbicides In 2009, Canada identified its first resistant weed, giant ragweed, and by that time 15 weed species had been confirmed as glyphosate resistant, in 2010, in the United States 7 to 10 million hectares (2.8 4.0 million hectares) of affected soil perweeds, or about 5% of the 170 million hectares planted with corn, soybeans and cotton, the most affected crop, in 22 states. In 2012, Charles Benbrook reported that the Weed Science Society of America listed 22 super weeds in the US, with more than 5.7 ÃÆ'â € "span> 10 ^ < ha <14 /s> 6 hectare) filled with weed GR and that Dow AgroSciences has surveyed and reported about 40 ÃÆ'â € " 10 10 6 hectare). International Survey of Weed Herbicide Weed database contains species that are resistant to glyphosate.
In response to resistant weeds, farmers do weeding by hand, using tractors to reverse the soil between plants, and using herbicides other than glyphosate.
The Monsanto scientists found that some resistant weeds had as many as 160 copies of additional genes called EPSPS, glyphosate enzymes disturbed.
Palmer amaranth
In 2004, the resistant glyphosate variation of Amaranthus palmeri , commonly known as Palmer amaranth, was found in Georgia and confirmed by a 2005 study. In 2005, resistance was also found in North Carolina. The widespread use of Roundup Ready plants causes an unprecedented selection pressure, and glyphosate resistance is followed. Weed variations are now widespread in the southeastern United States. Cases have also been reported in Texas and Virginia.
Conyza
Conyza bonariensis (also known as hairy fleabane and buva) and Conyza canadensis (known as horseweed or marestail), is another weed species that has recently developed glyphosate resistance. A 2008 study on the current situation of glyphosate resistance in South America concluded "the evolution of resistance following intense glyphosate use" and the use of glyphosate-resistant soybean plants is a factor that promotes increased use of glyphosate. In the 2015 planting season, a glyphosate-resistant marestail proved extremely problematic to be controlled in the Nebraska production field.
Ryegrass
Glyphosate-resistant ryegrass (Lolium ) has occurred in most of Australia's agricultural areas and other regions of the world. All cases of glyphosate resistance evolution in Australia are characterized by intensive use of herbicides while no other effective weed control practices are used. Studies show resistant ryegrass does not compete well against non-resistant plants and their number decreases when it does not grow under the conditions of glyphosate applications.
Johnson grass
Grass Johnson glyphosate resistant (Sorghum halepense ) is found in the cultivation of glyphosate resistant soybeans in northern Argentina.
Monarch butterflies
Use of 2-4 D and other herbicides such as glyphosate to clean milkweed along roads and fields may have contributed to the decline in the butterfly king population in the Midwestern United States. Along with deforestation and adverse weather conditions, the decline in milkweed contributed to an 81% drop in the kingdom. The Natural Resources Defense Council (NRDC) filed a lawsuit in 2015 against the EPA, in which it argued that it ignored warnings about the dangers of using glyphosate for the king.
Legal status
Glyphosate was first approved for use in the 1970s, and in 2010 was labeled for use in 130 countries.
European Union
In April 2014, the Dutch legislature issued a law prohibiting the sale of glifosms to individuals for use at home; commercial sales are not affected.
In June 2015, the French Ecology Minister asked for a nursery and garden center to stop selling glyphosate in the form of over-the-counter in the form of Roundup Monsanto. This is a non-binding request and all glyphosate sales remain legal in France until 2022, when it is planned to ban the substance for gardening at home. However, recently the French parliament decided not to impose a definite date for the ban.
The vote on glyphosate relicencing in the EU stalled in March 2016. Members said France, Sweden and the Netherlands objected to the update. Voting for reauthorization on a temporary basis failed in June 2016 but in the last minute the license was extended for 18 months until the end of 2017.
On November 27, 2017, the majority of the EU's eighteen member states voted in favor of the use of glyphosate herbicides for another five years. The majority of the 16 states representing 65% of EU citizens are required. Therefore, what determines is the German voice that supports sustainable use. CSU Agriculture Minister Christian Schmidt unexpectedly cast a favorable vote while the German coalition government was internally divided over the usual problems and usually led to German abstention.
Other countries
In September 2013, the El Salvador legislature approved a law to ban 53 agrochemicals, including glyphosate; the glyphosate ban is set to begin in 2015.
In May 2015, the president of Sri Lanka banned the use and import of glyphosate, effectively immediately. However, in May 2018 the Sri Lankan government decided to re-authorize its use in the plantation sector.
In May 2015, Bermuda blocked the import of all new orders of glyphosate-based herbicides for suspension while awaiting research results.
In May 2015, Colombia announced that it would stop using glyphosate in October 2015 in the destruction of illegal coca farms, raw materials for cocaine. Farmers complain that air fumigation has destroyed all the coffee fields and other legal products.
Legal case
Ad controversy
The New York Times reported that in 1996, "Dennis C. Vacco, the New York Attorney General, ordered the Monsanto company to withdraw advertisements saying that Roundup" is safer than table salt "and" almost non-toxic. "For mammals, birds and fish, the company pulls the place, but also says that the phrases in question are allowed under the EPA guidelines."
In 2001, French environmental and consumer rights activists took the case against Monsanto for misleading the public about the environmental impact of the Roundup herbicide, on the grounds that glyphosate, the main component of Roundup, was classified as "harmful to the environment" and "toxic to society". aquatic organisms "by the European Union Monsanto ads for Roundup have presented it as biodegradable and left the ground clean after its use In 2007, Monsanto was found guilty of false advertising and fined 15,000 euros The French distributor Monsanto, Scotts France, was also fined 15,000 euros ordered to pay 5,000 euros compensation to the Brittany Water and River Association and 3,000 to the Cadre de Vie Consommation Logement, one of the two major general consumer associations in France Monsanto appealed and the court upheld the verdict Monsanto appealed again to the Court Great France, and in 2009 also corroborated the verdict.
Alleged dumping trade
US companies have mentioned trade issues with glyphosate being dumped into western markets by Chinese companies and official disputes filed in 2010.
See also
- Monsanto's legal case
- 2,4-Dichlorophenoxyacetic acid
- Ammonium sulfamate
- Atrazine
- Environmental impact of pesticides
- The health effects of pesticides
- Integrated pest management
- SÃÆ' Â © ralini infidelity
References
External links
- Glyphosate in Pesticide Properties DataBase (PPDB)
- trimeta Glyphosate in Database of Pesticide Data (PPDB)
- Glyphosate, isopropylamine salt in Pesticide Properties DataBase (PPDB)
- Glyphosate, potassium salt in Pesticide Properties DataBase (PPDB)
Source of the article : Wikipedia
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