A recent clinical study on mice, published in Neuroinflammation (Bartholomew et al., 2024), demonstrates the correlations between exposure to glyphosate and inflammation of brain tissue with increased risk of neurodegenerative diseases such as Alzheimer’s disease. In addition to a higher incidence of premature mortality. (1)
1) Glyphosate, the most widely used herbicide in the world
The glyphosate is still the most widely used herbicide worldwide. Its use has increased significantly, mainly due to the introduction of GMO crops specifically designed to resist it (i.e. Roundup-ready), starting from the now distant 1996.
Herbicide-resistant crops today represent 94-100% of GMOs grown in the USA, Argentina, and Brazil. And they are treated with quantities of glyphosate that far exceed those on the basis of which the use of this substance was authorized, as we have seen. (2)
2) Exposure levels and health risks
Levels of exposure to glyphosate are significant not only for farmers and communities living in areas where it is used but also for consumers who absorb it through non-organic foods that contain it. As seen in 99,8% of nearly 7.000 French citizens from different regions. (3)
The health risks human risks identified so far concern genotoxicity and carcinogenesis (with particular regard to non-Hodgkin’s lymphoma), endocrine disruption and damage to the microbiome, antibiotic resistance, celiac disease (4-9). The risks of neurotoxicity have instead been underestimated so far (10,11).
3) Glyphosate and inflammation of brain tissue, the study
Researchers of Arizona State University (Tempe, AZ, USA) administered different doses of glyphosate to three groups of mice for 13 weeks. Taking into account the NOAEL (no observed adverse effect level) established by the EPA (Environmental Protection Agency, USA) for chronic exposure of mice (90 days), on the basis of which the chronic reference dose for humans is calculated (1,75 mg/kg/day). The three groups were then subjected to 6 months of recovery, neurocognitive tests and tissue examinations.
The results firstly show a correlation between glyphosate exposure and increased incidence of premature mortality. Glyphosate and its main metabolite aminomethylphosphonic acid were found to be present in brain tissue – even after the recovery period – with corresponding increases in the proinflammatory cytokine tumor necrosis factor-⍺ (TNF-⍺) in the brain and peripheral blood plasma. TNF-⍺ has also been found to be elevated in neurodegenerative disorders such as Alzheimer’s disease (AD), and glyphosate exposure has been shown to act as an accelerator of AD pathogenesis.
4) Provisional conclusions
‘Collectively, these data demonstrate that Early exposure to glyphosate increases neuropathology similar to Alzheimer’s disease in mice‘ (Bartholomew et al., 2024).
Significant and long-lasting, dose-dependent increases in the levels of pro-inflammatory cytokines in circulating blood in turn explain the increase in premature mortality.
‘As the use of glyphosate continues to increase, further research is needed to clarify the impact of this herbicide and its metabolites on the human brain and their potential contribution to the increased prevalence of neurodegenerative diseases‘.
Dario Dongo
Cover image: ‘Graphical summary of our main findings highlighting that glyphosate exposure followed by a significant recovery period was able to cause long-lasting pathological consequences’ (Bartholomew et al., 2024, Figure 6). (1)
Footnotes
(1) Bartholomew, S.K., Winslow, W., Sharma, R. et al. Glyphosate exposure exacerbates neuroinflammation and Alzheimer’s disease-like pathology despite a 6-month recovery period in mice. J Neuroinflammation 21, 316 (2024). https://doi.org/10.1186/s12974-024-03290-6
(2) Dario Dongo. Glyphosate and GMO soybeans, the big scam. Scientific study. FT (Food Times). January 6, 2020
(3) Marta Strinati. Glyphosate in the urine of 99.8% of French people. FT (Food Times). January 15, 2022
(4) Dario Dongo. Glyphosate, more fraud in scientific studies produced by ‘corporations’. FT (Food Times). February 16, 2020
(5) Dario Dongo, Sabrina Bergamini. Glyphosate increases risk of non-Hodgkin’s lymphoma, new study finds. FT (Food Times). February 15, 2019
(6) Dario Dongo, Andrea Adelmo Della Penna. Glyphosate, endocrine disruption and cancers. New evidence. FT (Food Times). November 20, 2020
(7) Marta Strinati. Glyphosate ‘masculinizes’ females. The scientific study of infants. FT (Food Times). April 3, 2021
(8) Marta Strinati. Glyphosate causes antibiotic resistance in hospital bacteria. FT (Food Times). November 19, 2022
(9) Marta Strinati. Glyphosate and gluten intolerance, possible correlations. GIFT (Great Italian Food Trade). 11.2.24
(10) Dario Dongo. Glyphosate and neurotoxicity, doubts and questions from a toxicologist. GIFT (Great Italian Food Trade). 3.11.23
(11) Izumi, Yukitoshi; O’Dell, Kazuko A.; Zorumski, Charles. Glyphosate as a direct or indirect activator of pro-inflammatory signaling and cognitive impairment. Neural Regeneration Research 19(10):p 2212-2218, October 2024. Doi: 10.4103/1673-5374.391331 CC
Dario Dongo, lawyer and journalist, PhD in international food law, founder of WIISE (FARE - GIFT - Food Times) and Égalité.
