: Glyphosate is sold under dozens of tradenames. Besides RoundUp, these include Clearout, Credit, Factor, Glyfos, Knockout, Maverick, Polaris, Pondmaster, Rodeo, SharpShooter, Touch Down, Traxion, Vantage, and many others.
Class and Uses
: Glyphosate is an aminophosphonic analogue of the natural amino acid glycine. It is a broad-spectrum systemic herbicide used to kill weeds, especially annual broadleaf weeds and grasses. In 2007 glyphosate was the most used herbicide in the United States agricultural sector and the second most used in home and garden market. Some crops have been genetically engineered to be resistant to glyphosate (i.e., "Roundup Ready). Such crops allow farmers to use glyphosate as a post-emergence herbicide against both broadleaf and cereal weeds, which has greatly increased its use.
: Glyphosate can be acutely toxic to non-target plants, including aquatic plants and algae. The effects of this toxicity on natural plant succession alters the ecology of treated areas. In most cases, the plant species diversity will decrease, and along with it, the numbers of insects, mammals and birds utilizing these areas as habitat. Another major concern about RoundUp/ glyphosate is that with the huge usage of it, more and more weeds are becoming resistant to it. RoundUp was marketed with the premise that use of RoundUp ready crops would allow the use of less herbicides. In fact the volume of glyphosate used increased 10-fold from 15 million pounds in 1996 to 159 million pounds in 2012 AND total volume of herbicides used has risen by 26 percent from 2001 to 2010.
Glyphosate does reduce the growth of beneficial soil-dwelling mycorrhizal fungi, which function to increase nutrient uptake by plants through a symbiotic association with the roots. Mycorrhizae have been implicated in the improved resistance to stress, and are necessary for the proper growth and development of most vascular plants. Glyphosate destroys nitrogen-fixing bacteria in the soil. Glyphosate, by inhibiting the growth of some microbes, allows the overgrowth of others. This includes microbial plant pathogens. Fusarium is a naturally occurring soil fungus that is a plant pathogen. Fusarium invades the roots of plants and either kills the plant outright or prevents normal growth. Thus plants in areas treated with glyphosate will be more vulnerable to fusarium and other pathogens. By all these means glyphosate is harmful to plants and in the environment.
: In general, glyphosate is of low toxicity to birds and mammals. This is because its mode of action is through blocking a specific enzyme pathway used in biosynthesis, called the shikimic acid pathway. The shikimic acid pathway is present in plants, fungi, and bacteria but is not found in higher animals. The absence of this pathway in mammals may explain the low toxicity of glyphosate to non-target organisms. However, commercial formulations of glyphosate contain additives such as surfactants which vary in nature and concentration. These other ingredients, labelled as â€œinert,â€ may be more toxic than the glyphosate. Glyphosate alone is practically non-toxic to fish. However, Roundup is apparently more toxic to fish than many common surfactants. Roundup is listed as â€œrelatively non-toxicâ€ to honeybees. However, there is some anecdotal evidence of a connection between aerial spraying of Roundup and death of bee colonies.
: RoundUp was marketed as the ideal herbicide, toxic to weeds and harmless to everything else. For years glyphosate was assumed to be non- toxic to humans. The EPA considers glyphosate to be non-carcinogenic and relatively low in dermal and oral acute toxicity. However, as noted, most health studies have focused on the safety of glyphosate, rather than the mixture of ingredients found in RoundUp. Also most toxicity tests cited by industry and the EPA investigate toxicity through oral exposure routes. The toxicity of glyphosate and its common surfactant POEA is much greater through inhalation routes of exposure. Roundup is the third most commonly reported cause of pesticide related illness among agricultural workers. Humans ingesting as little as 100 ml of Roundup have died (suicide attempts using Roundup have a 10-20% success rate).
Now researchers have found that one of Roundupâ€™s inert ingredients can kill human cells, particularly embryonic, placental and umbilical cord cells. The research team suspects that Roundup might cause pregnancy problems by interfering with hormone production, possibly leading to abnormal fetal development, low birth weights or miscarriages. Roundup is a potent endocrine disruptor (disturbs hormone function) even at very low concentrations.
Another mode of harm to animals and humans from glyphosate is through its action against microbes, including beneficial microbes in the gut. A recent study in the Journal of Current Microbiology reported that such highly pathogenic bacteria as Salmonella Entritidis, Salmonella Gallinarum, Salmonella Typhimurium, Clostridium perfringens and Clostridium botulinum were highly resistant to glyphosate. However, most of beneficial bacteria such as Enterococcus faecalis, Enterococcus faecium, Bacillus badius, Bifidobacterium adolescentis and Lactobacillusspp. were found to be moderate to highly susceptible. A reduction of beneficial bacteria in the gastrointestinal tract microbiota by ingestion of glyphosate could disturb the normal gut bacterial community, especially since the pathogenic microbes were left unharmed.
Fate in the Environment
: Glyphosate adsorbs strongly to soil and is not expected to move vertically below the six inch soil layer. However, glyphosate does have the potential to contaminate surface waters due to its aquatic use patterns and through erosion, as it adsorbs to soil particles suspended in runoff. If glyphosate reached surface water, it would not be broken down readily by water or sunlight. Glyphosate's toxicity is compounded by its persistence in the environment. Even though it has been marketed as being very biodegradable, many studies show that glyphosate remains, chemically unchanged in the environment, for periods of up to a year. Recent research suggests that even when glyphosate binds to soil particles, it will cyclically "desorb" or lose its attraction to soil and become active as an herbicide.
Glyphosate was detected in between 60 and 100% of air and rain samples taken in the American Midwest during the crop growing season. Glyphosate and its main breakdown product, AMPA, were frequently detected in streams in the American Midwest during the growing season. Urinary body burdens of glyphosate in farm and non-farm families in Iowa were over 900 parts per billion (0.9 mg per kg of body weight) in 75% of farmers, 67% of wives, and 81% of farmersâ€™ children. Urinary burdens in non-farm children were slightly higher than those in farm children, perhaps due to the widespread use of glyphosate in non-farm areas, such as in peopleâ€™s gardens.
https://pmep.cce.cornell.edu/profiles/ex ... e-ext.html
https://www.scientificamerican.com/artic ... rbicide-p/
https://earthopensource.org/index.php/4- ... w-toxicity
https://www.abcbirds.org/abcprograms/pol ... osate.html
https://www.forbes.com/sites/bethhoffman ... -not-less/
(J Current Microbiology)
https://www.motherearthnews.com/homestea ... z31EZ6tWdc