Ingestion of RoundUp has been shown to cause "irritation of the oral mucous membrane and gastrointestinal tract…pulmonary dysfunction, oliguria, metabolic acidosis, hypotension, leukocytosis and fever."
Monsanto's own toxicologist, Rebecca Tominack, participated in this study.
(Tominack RL, Yang GY, Tsai WJ, Chung HM, Deng JF, 1991. Taiwan National Poison Center survey of glyphosate-surfactant herbicide ingestions. J Toxicol Clin Toxicol 1991; 29 (1): 91-109)
Many people report experiencing severe digestive problems related to irritation of their gastrointestinal tract after overexposure to RoundUp, limiting the foods their bodies will tolerate to a very few bland foods.
This is believed to be related to the fact that in a 1983 study by Heitanen, Linnainmaa and Vainio, RoundUp's main ingredient, glyphosate, was shown to decrease the hepatic level level of cytochrome P-450, monooxygenase activities, and the intestinal activity of aryl hydrocarbon hydroxylase.
The inhibition of erythrocyte glutathione conjugate transport by polyethoxylated surfactants has also been reported in a 1993 letter to FEBS from studies done by P. G. Board, part of the Molecular Genetics Group, John Curtin School of Medical Research, Australian National University, Canberra.
Glutathione is a tripeptide which the body produces from the amino acids cysteine, glutamic acid, and glycine. Glutathione is a powerful antioxidant produced in the liver, where it detoxifies harmful compounds so that they can be excreted through the bile. The glutathione released from the liver directly into the bloodstream helps to maintain the integrity of red blood cells and protect white blood cells. Glutathione is also found in the lungs. In the intestinal tract, it is needed for carbohydrate metabolism, and also appears to exert anti-aging effects, aiding in the breakdown of oxidized fats that may contribute to atherosclerosis. Glutathione's role in carbohydrate metabolism is compromised by the effect of RoundUp's surfactant, POEA, on erythrocyte glutathion conjugate transport.
RoundUp causes damage to the liver that inhibits the liver's ability to process toxic substances.
Research subject animals injected with glyphosate evidenced a depressed function of the liver. "Glyphosate decreased the hepatic function of cytochrome P-450 and monoxygnease activities and the intestinal activity of aryl hydrocarbon hydrolase." (Heitanen et al, 1983). The P-450 enzyme system is one of the main body systems for detoxifying harmful chemicals. When it becomes impaired by those same chemicals it is supposed to be detoxifying, the effects of a given chemical on the body increase dramatically.
(Heitanen, et al., 1983. Effects of phenoxyherbicides and glyphosate on the hepatic and intestinal biotransformation activities in the rat. Acta Pharmacol Toxicol (Copenh) 1983 Aug; 53(2):103-12.)
Testing of patients suffering RoundUp overexposure has indicated damage to their P-450 enzyme system.
Roundup produces significant increases in sister-chromatid exchanges (SCE), albeit in higher concentrations over those used for other pesticides. This suggests that it should be evaluated in other genetic tests measuring mutations and chromosome aberrations, although few studies of this nature have yet been done.
A 1980 study by Vigfusson and Vyse noted sister-chromatid exchanges in human lymphocytes in vitro. This lymphocyte disturbance correlates with the swelling experienced by persons poisoned by RoundUp.
(Vigfusson, N.V. and Vyse, E.R. (1980), "The effect of the pesticides, Dexon, Captan, and Roundup, on sister-chromatid exchanges in human lymphocytes in vitro". MUTATION RESEARCH, v.79 p.53-57.)
William Meggs, M.D., Ph.D., School of Medicine, East Carolina University:
In patients who have been chemically injured, Meggs has noted significant lymphatic hyperplasia, lymphatic tissue that is swollen and engorged. He has also found significant cobblestoning in upper airway passages. This represents chronic inflammation caused by lymphocytes migrating out of the blood stream and seeping into the tissues. Meggs has also noted thickening of the structure called the basement membrane, the structure on which the lining of cells that lines the interior of the nose sits. Meggs' study also found a defect in the tight junctions (the joining of cells together) and a proliferation of nerve fibers.
"Chemicals bind to receptors on nerve fibers and produce something called neurogenic inflammation. These chemicals bind to these receptors and cause the release of potent substances that produce inflammation in tissue.
When chemicals bind to nerve fibers, they can produce inflammation. Inflammation, in turn, produces other changes in the tissue, and it brings in these lymphocytes. We believe that inflammation causes these barrier cells to open up and sometimes even come off the basement membrane. Below the basement membrane is the nerve fibers, so we have a process whereby a chemical exposure will damage the lining of the nose.
What happens is people have a large chemical exposure, they breathe in noxious chemicals, and this damages the epithelium. This huge exposure is able to penetrate this barrier we have between the chemicals we breathe in and these nerve cells beneath the lining layer that react to chemicals by producing inflammation. The inflammation, in turn, produces substances that cause further damage to the lining cell, and actually produce the substances which cause the tight junctions between these cells to open up. In some cases the cells actually come off and just leave these bare nerves exposed. Once you have the bare nerves exposed, low levels of chemicals that we all experience every day are enough to produce inflammation which in turn keeps the epithelium damaged."
RoundUp was found to cause significant DNA damage to erythrocytes (red blood cells) in a study done in 1997 by Clements, Ralph and Petras. RoundUp's surfactant, POEA, is known to cause haemolysis.
(Clements C, Ralph S, Pertas M, 1997. Genotoxicity of select herbicides in Rana catesbeiana tadpoles using the alkaline single-cell gel DNA electrophoresis (comet) assay. Environ Mol Mutagen 1997; 29(3):277-288.)
(Sawada Y, Nagai Y, Ueyama M, Yamamoto I, 1988. Probable toxicity of surface-active agent in commercial herbicide containing glyphosate. Lancet. 1988 Feb 6;1(8580):299.)
In haemolysis, hemoglobin leaks from the red blood cells, leaving them unable to transport sufficient supplies of oxygen to the body's tissues.
The chest pains, difficulty breathing, and impaired cognitive skills reported by persons who have sustained RoundUp poisoning also point to impairment of the blood's oxygen transport system, hemoglobin, as being responsible for these symptoms. This impairment of the erythrocytes' ability to deliver adequate oxygen to both brain and body results in impaired tissue perfusion and hypoxia.
"The brain is particularly vulnerable to hypoxia, and exposure to toxins that interfere with the intake, transport and utilization of oxygen provoke rapid and major neuronal damage. Compounds crossing the blood-brain barrier may induce both general and extremely localized neurotoxic effects."
(Kyvik KR, Morn BE, 1995. Environmental poisons and the nervous system. Tidsskr Nor Laegeforen 1995. June 10; 115(15):1834-8.)
According to both the EPA and the World Health Organization in 1993 and 1994, glyphosate appears to mimic adrenaline. This would explain the sleeping problems encountered by many persons exposed to RoundUp, as for them, cortisol appears to no longer be properly regulated by their bodies' adrenal glands.
(US EPA, 1993. EPA Reregistration Eligibility Document, Glyphosate, Office of Prevention, Pesticides and Toxic Substances, Washington, D.C., September 1993.)
(IPCS, 1994. Environmental health criteria 159: Glyphosate. International Programme of Chemical Safety, World Health Organization, Geneva.)