New Study Reveals Glyphosate Can Form From Chemical Reactions
A new study reveals glyphosate, one of the most widely used herbicides globally, is not just found through direct agricultural application. Instead, it can be formed from the chemical diethylenetriamine penta(methylenephosphonate) (DTPMP) through reactions involving manganese under environmental conditions. Published on March 11, 2025, this groundbreaking research prompts scientists to rethink existing models of glyphosate contamination, emphasizing the role of complex chemical interactions over simple herbicide usage.
Glyphosate has become synonymous with modern agriculture since its launch and subsequent use skyrocketed with the advent of genetically modified crops. Traditionally believed to enter the environment solely through agricultural runoff, glyphosate along with its primary metabolite, aminomethylphosphonic acid (AMPA), has been detected at alarming levels across surface and groundwater systems worldwide. Understanding the persistence of glyphosate—a substance commonly assumed to degrade swiftly—has become increasingly important as its presence continues to pose environmental challenges.
Researchers from the University of Tübingen, Germany, conducted systematic experiments to explore the transformation of DTPMP, utilized widely as a chelators—agents used to bind metal ions—in household and industrial applications. By reacting DTPMP with manganese under conditions representative of various water systems—including buffered pure water and sterile-filtered wastewater—they found substances such as manganese oxide (MnO2) play a pivotal role. The conversion process produces glyphosate via multiple steps under controlled conditions, challenging the prior single-source perspective of glyphosate contamination.
During the experiments, the concentration of manganese—a mineral ubiquitous across natural waters—was varied alongside the presence of dissolved oxygen. The results revealed significant findings: glyphosate yield reached as high as 0.42 mol%. Interestingly, glyphosate was formed even after DTPMP had been fully converted, leading researchers to suspect the involvement of yet unidentified intermediate compounds. This transformation, noted for its efficient kinetics, raises concerns about current agricultural and wastewater management practices.
The conditions under which the glyphosate formed did not merely depend on the chemical concentration but on the specific environmental parameters, such as pH and temperature. Under oxic conditions (oxygen present), rapid transformations of DTPMP to glyphosate were observed; for example, with 1.0 g/L MnO2, complete transformation occurred within 20 minutes at pH 6. Conversely, when oxygen was absent, transformations slowed significantly, demonstrating how environmental factors significantly impact chemical pathways.
Notably, the research team estimated significant phosphonate consumption across Europe, documenting annual usage rates of 49,000 metric tons of polyphosphonates for various applications, including cleaning products. Practical figures highlighted 7613 metric tons used for household detergents alone by 2019. Concern arises from such usage as it links back to unintended glyphosate production, marking DTPMP as potentially the overlooked source for glyphosate contamination across water systems.
“Glyphosate yields vary with the reaction conditions and reach up to 0.42 mol%,” stated the researchers. This declarative finding emphasizes the urgency for environmental scientists and policymakers alike to integrate these parameters when evaluating herbicide dynamics in aquatic systems.
The study elucidated the formation processes, showing AMPA can also derive from the same treatment conditions, with yields observed exceeding 10 mol% under specific experimental setups. The presence of AMPA as the primary transformation product of glyphosate shows the complexity and significance of trace chemical interactions exacerbated by human industrial activities.
“Once DTPMP was completely transformed, the concentrations of glyphosate and AMPA remained constant or even increased within one to ten days of kinetic experiments,” the authors noted, indicating prolonged environmental persistence of these compounds under varying conditions, heightening the concern for water sources.
These results not only provoke questions about the common perception of glyphosate’s environmental impact but also call for reexamining existing regulatory frameworks. Effective management strategies for contaminated water bodies now require considering these newly identified pathways of glyphosate formation, as the reaction does not solely rely on direct agricultural factors but rather on industrial chemical residues and processes.
Environmental experts are now emphasizing the possible need for revisiting glyphosate’s environmental impact assessments. The predominant belief had been glyphosate contamination stemmed directly from agricultural practices; this study introduces the risk of chemical formation through other ubiquitous compounds often overlooked. Therefore, professionals urge the reevaluation of water protection strategies, as relying solely on herbicide application data may no longer suffice.
To conclude, the study’s insights advocate for adopting wider perspectives on chemical interactions within ecosystems, where industrial chemicals like DTPMP can inadvertently transform, perpetuating herbicide presence across habitats. With the permeation of knowledge detailed herein, scientists may work collaboratively to establish more effective guidelines and preventive measures, ensuring safer water quality and environmental integrity moving forward.
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