Glyphosate Residues Research Articles

Low background dual-ligand Cu-MOF nanoprobe for plant tissue imaging and fast screening as well as sensitive detection of glyphosate in environmental samples

The monitoring of glyphosate residue in environmental samples is critically important due to its high environmental risk. Here, we reported a low background dual-ligand and fast response copper-based metal organic framework (Cu-MOF) nanoprobe for imaging glyphosate in plant tissue, rapid screening of glyphosate-contaminated samples, and sensitive detection of glyphosate in environmental samples. The Cu-MOF nanoprobe was prepared with 2-Aminoisophthalic Acid (AIA) and trimesic acid (H3BTC) as ligands, and Cu2+ as a metal node. Thanking to both ligand-to-metal charge transfer (LMCT) and photoinduced electron transfer (PET) effects, the fluorescence of ligand AIA could be fully quenched in Cu-AIA/BTC probe. Upon the addition of glyphosate, it competed with the ligands in Cu-AIA/BTC probe, causing the collapse of MOF structure and the release of ligand AIA with obvious fluorescence recovery. This nanoprobe exhibited a desirable linear response for glyphosate in the concentration range of 0.1–80 μM, with a low detection limit of 33 nM, much lower than the maximum contaminant level (4.1 μM) set by the U.S. Environmental Protection Agency (EPA). Furthermore, it was also successfully applied for plant tissue imaging, fast screening of glyphosate-contaminated samples and monitoring of the degradation of glyphosate on tea leaves and in soil, indicating the broad application prospect of the nanoprobe.

Dual-mode strategy for glyphosate detection: Leveraging competitive interaction with iron and zinc-organic frameworks

The extensive use of glyphosate poses a potential threat to food safety, human health, and the ecological environment. Hence, detecting glyphosate residues in food is of great significance for food safety. In this work, the synthesis of zinc-organic frameworks (Zn-MOFs) was achieved through the coordination of Zn2+ with the 2,5-dihydroxyterephthalic acid (DOBDC) ligand. Upon excitation at 350 nm, these Zn-MOFs exhibited robust fluorescence emission at 533 nm. However, upon the addition of iron ions, the Zn-MOFs structure disintegrated, forming a blue Fe-DOBDC complex, resulting in fluorescence quenching. In the presence of glyphosate, the iron ions were chelated by glyphosate, causing the system to lighten in color and restore fluorescence. Further, the mechanism of this strategy was investigated, which was achieved by utilizing the competitive interaction of glyphosate and Zn-MOFs for iron ions. The binding stoichiometry and binding constant of glyphosate:Fe3+ are 1:1 and 7.59 × 103 M−1 using the Job's plot and Benesi-Hildebrand equation, respectively. To enhance glyphosate detection, this study introduced an ingenious dual-mode strategy. By analyzing the colorimetric and fluorescence changes before and after glyphosate addition, we can accurately determine its concentration in the system. The combined colorimetric and fluorescent modalities offer improved reliability and applicability, boasting simplicity, rapidity, and cost-effectiveness. This innovative method is anticipated to find widespread applications and offers novel perspectives on pesticide detection platforms based on ligand competition effects.

Saga of Soggy Sauerkraut

The creation of undesirable (soggy) sauerkraut resulted in the loss of $1,000,000 worth of organic sauerkraut in 2022, which prompted a multistep investigation of the cause and potential solution. The cause of this condition has been previously reported as unique fermentation conditions and the lack of key trace nutrients essential for cabbage (Brassica oleracea var. capitata) cell wall integrity. Because the condition was limited to organic sauerkraut in 2022, this investigation initially focused on differences in fermentation conditions between organic and conventional sauerkraut. No differences in fermentation conditions accounted for the condition; therefore, attention was focused on analyzing the mineral content of cabbage grown for sauerkraut production that pinpointed a deficiency in critical micronutrients such as iron, copper, manganese, boron, and zinc. This deficiency was traced to the use of poultry manure that was contaminated with glyphosate residue from conventionally fed turkeys and chickens that consumed genetically engineered (GE) feed and used as the fertilizer for organic cabbage production. The presence of glyphosate, a potent mineral chelator and antibiotic, was identified as a significant factor that impairs the absorption and physiological function of essential minerals in the shikimate metabolic pathway whereby cell walls and lignin are produced, thus compromising the structural quality of the sauerkraut. After this discovery, the study progressed to evaluate various remediation strategies aimed at eliminating glyphosate from the soil and restoring nutrient uptake. Corn grain and silage were selected as the test crops for this phase. Among the tested remediation solutions were raw sauerkraut juice containing Lactobacillus plantarum, which is reported to degrade glyphosate in the rumen of dairy cows and two patented proprietary microbial mixtures, PB027 and PB027SK, that degrade glyphosate by all three of the known metabolic pathways. These treatments were specifically formulated to degrade residual glyphosate in the soil. The results showed that these interventions could reduce soil glyphosate levels by 80% to 90% within 6 to 7 months to significantly enhance both the yield and quality of corn grain and silage. The increase in corn grain yield from glyphosate degradation on the Shiocton silt loam soil was 907.89 kg·ha−1 (13.5 bushels/acre). The increase in yield on the irrigated Kidder sandy loam soil was quantified at 726.31 kg·ha−1 (10.8 bushels/acre) for corn grain and 6.62 t·ha−1 (2.68 t/acre) for silage, with an additional improvement in silage feed quality beneficial for milk production. The findings underscore the importance of addressing both micronutrient sufficiency and glyphosate residue in soil to ensure the optimal growth of cabbage and the quality of sauerkraut produced. By successfully identifying manure as a subtle source of nutrient immobilization and implementing effective soil remediation techniques, this research highlights a clear path forward for improving crop yield and quality to ultimately enhance the structural integrity and consumer acceptance of sauerkraut. This study has broader applications for the nutritional content and crop yields of many organic crops that use conventional poultry and animal manures that may contain glyphosate in desiccated plant tissues or GE feeding operations.

Multifunctional effects of nitrification and urease inhibitors: Decreasing soil herbicide residues and reducing nitrous oxide emissions simultaneously

Glyphosate pollution and greenhouse gas emissions are major problem in achieving sustainable soil management. It is necessary to develop effective strategies to simultaneously reduce herbicide residues and nitrous oxide (N2O) emissions in soil. This study aimed to: (1) quantitative analyze the effects of nitrogen (N) cycle inhibitors (nitrification inhibitors 3,4 dimethylpyrazole phosphate (DMPP) and dicyandiamide (DCD) and urease inhibitor N-(n-butyl) thiophosphoric triamide (NBPT)) on glyphosate degradation and reduction of N2O under different soil moistures; (2) identify the functional microbes and genes associated with glyphosate degradation and N2O emissions; and (3) decipher the main mechanisms of N cycle inhibitors affecting glyphosate degradation at different soil water contents. Compared to the control, the application of DMPP, DCD and NBPT reduced glyphosate residues in soil by 33.0 %, 60.3 % and 35.7 %, respectively, under 90 % water holding capacity (WHC). The application of DCD stimulated Acidobacteria and the phnX gene to degrade soil glyphosate. Further, soil glyphosate residues were significantly and negatively related to soil N2O emissions at both 60 % and 90 % WHC. Compared to the control, NBPT application decreased cumulative N2O emissions by 91.4 % at 90 % WHC by decreasing soil nitrate N (NO3--N) and inhibiting amoC and narG genes at 90 %. The application of N cycle inhibitors could be a potential strategy to simultaneously reduce glyphosate residues and soil N2O emissions. Our study could provide technical support to reduce the risks of herbicide exposure and reduce greenhouse gas emissions.

Alternative Method for Glyphosate Determination in Unroasted Green Coffee Beans by Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS).

This research proposes an alternative method to detect and quantify glyphosate residues in unroasted green coffee beans by LC-MS/MS. The sample preparation was conducted without derivatization steps, with integrated cleanup, which improves the analytical method's frequency. Validation results were consistent with the requirements of the regulatory guidelines employed. Specificity, linearity (r2 = 0.9991), precision (RSD ≤ 9%), and recovery (92-112%) were ensured, with a satisfactory limit of quantification (LOQ = 0.48 mg kg-1). These data demonstrate that the method is suitable for monitoring glyphosate residues in unroasted coffee beans while offering simplicity and speed in sample preparation. The method was applied to analyze authentic unroasted coffee bean samples, in which two of them were contaminated with glyphosate (<LOQ). These results exhibit the importance of glyphosate monitoring in coffee samples and enhance that the method can be successfully implemented as a tool to guarantee food quality and safety.

Development of a novel ternary MOF nanozyme-based smartphone-integrated colorimetric and microfluidic paper-based analytical device for trace glyphosate detection

Given the significant and potential fatal implications of glyphosate (GLY) residues on human health and the integrity of ecosystems, their presence has garnered substantial global concern and scrutiny. Herein, we introduced a pioneering colorimetric sensing platform, the first of its kind, based on ternary metal-organic frameworks (ZnCo-ZIFs@MIL-101(Fe)). This innovative platform enabled ultra-sensitive, affordable, portable and rapid on-site detection of GLY. This platform achieved a wider linear range for GLY of 0.02–40 μg/mL with an exhibiting remarkable detection limit of 1 ng/mL, which was attributed to the electronic hybridization of the Fe3+, Co2+, and Zn2+ metal centers of ZnCo-ZIFs@MIL-101(Fe), significantly enhancing the composite's catalytic performance. The assay was successfully employed to detect GLY in food and herb samples. Moreover, to meet the demand of in-field detection for GLY, a smartphone detection method based on ZnCo-ZIFs@MIL-101(Fe) with visual, intelligent, and portable features was fabricated. This detection concentration range of GLY was 0–1 μg/mL, and the limit of smartphone detection was 23 ng/mL. Furthermore, this sensor seamlessly integrated with smartphones and paper-based microfluidic chips (μPADs), which constructed a portable test strips-smartphone sensing platform for facilitating real-time and on-site visual quantitative detection of GLY. The detection concentration range was 0–1 μg/mL, and the limit was calculated as low as 75 ng/mL. The assay was highly adaptable in practical applications. In summary, our study paved a novel pathway for the design and utilization of multi-metal MOF nanozymes in on-site pesticide monitoring.

Ratiometric fluorescence probe based on boric acid-modified carbon dots and alizarin red for sensitive and rapid detection of glyphosate.

Bycombining boric acid-modified carbon dots (p-CDs) and alizarin red (ARS), a double emission probe p-CDs@ARS with fluorescence at 410nm and 600nm is designed for the detection of glyphosate. When Cu2+ is added, it binds with ARS to cause ARSreleasefrom p-CDs@ARS, which decreases the fluorescence at 600nm. However, in the presence of glyphosate, glyphosate competes to thebinding ofCu2+, releasing ARS to bind with p-CDs again. Therefore, the fluorescence of 600nm recovers. Based on this, the fluorescence of 410nm and 600nm act as the reference and response signal, respectively,achieving the ratiometric fluorescence detection of glyphosate. The linear range of glyphosate detection is 0.5-50µM with a limit of detection at 0.37µM which is well below the maximum residue limit for glyphosate in food. When the probe is used to detect the glyphosate residue in Pearl River water and cucumber, the detection results are well consistent with those detected by HPLC. The established method based on p-CDs@ARS has the advantages that the assembly of ratiometric fluorescence probe is simple, and the detection speed is fast. Additionally, a typical INHIBIT logical system has been successfully constructed based on glyphosate, Cu2+, and the fluorescence signal of p-CDs@ARS.

Glyphosate detection based on Eu coordination polymer through competitive coordination

Glyphosate is a widely used herbicide in agriculture, leading to residues in food and water environments. These residues have been associated with heart disease and neurotoxicity. Therefore, it is urgent to develop new types of sensors for the detection of glyphosate residues. Here, a new coordination polymer, named as HNU-89, is synthesized by the assembly of Eu3+ and coumarin-3-carboxylic acid (HCCA). Benefiting from the hydrophobic ligands, HNU-89 can maintain its structure at pH 2–11. In view of that phosphoric groups in glyphosate molecules can coordinate with Eu3+ and compete with the HCCA ligand, according to the competitive coordination, the interaction weakens the red fluorescence of HNU-89 simultaneously enhancing the blue fluorescence of HCCA, which achieves the ratio fluorescence response for glyphosate detection. The limit of detection (LOD) is 0.08 ppm, meeting the requirements as a sensor. Furthermore, HNU-89 was utilized to detect glyphosate in soybean, corn, rice and tap water.

Effects of different timing and rate of glyphosate application on the residue level, grain quality, and processing performance of two Canadian malting barley varieties

AbstractBackground and ObjectivesA preharvest application of glyphosate on malting barley can assist in the management of perennial weed growth before harvest and serves as a harvest aid by drying down the crop. The main objective of this study was to assess the effects of preharvest glyphosate application at two glyphosate rates (900 or 1125 g ae/ha) and three application timings based on the maturity and seed moisture level (soft dough, hard dough, or mature).FindingsThe levels of glyphosate residue in barley grain were highly variable among locations and years ranging from 0 to 95 mg/kg. Glyphosate application at both rates at the soft dough stage significantly decreased the kernel weight of barley grain. Barley grain with up to 40 mg/kg of glyphosate residue exhibited adequate germination energy required for malting purposes; however, the residue negatively affected the growth of roots during the malting process. The levels of α‐amylase in malt decreased with increasing levels of glyphosate residue in barley. Other malt and wort parameters were generally not affected by the glyphosate application on barley.ConclusionsToo early application of glyphosate at the soft dough stage of barley grain development reduced the kernel weight and size, interfered with roots production, affected synthesis of α‐amylase, and reduced the malt extract in several cases.Significance and NoveltyResults indicated that in the majority of environments, when glyphosate was applied at the recommended stage and rate, neither the maximum residue limit was exceeded nor were the germination and malting quality of barley impaired. In real farming conditions, it might be hard to achieve similar results despite adherence to the recommended timing of glyphosate application because of the nonuniform level of crop maturity in the field and/or uncontrollable environmental effects.

Greenhouse study and interviews indicate glyphosate residue via feed-feces-fertilizer route is a risk for horticultural producers using manure-based fertilizer

BackgroundThe herbicide glyphosate is the most widely used active ingredient in pesticides globally. Residues have been found in people, livestock, food and animal feed, and in the environment, but little is known about glyphosate residue in manure-based fertilizer. We describe a feed-feces-fertilizer route of glyphosate contamination with negative impacts for horticultural production. This exposure can harm sensitive plants, such as tomato, and pose a risk to effective waste disposal and nutrient cycling along principles of the circular economy.We review the use and history of glyphosate and present a mixed methods research based on a real-world case from Finland where glyphosate residue in poultry manure fertilizer was suspected of inhibiting commercial organic tomato production. To test the fertilizer, we grew 72 ‘Encore’ variety tomato plants for 14 weeks in a climate-controlled greenhouse according to the practices of the commercial grower. To ascertain awareness and potential contamination mitigation measures, we contacted five fertilizer companies with sales of biogenic fertilizer in Finland, two farming organizations, a feed company, and two government organizations working on nutrient cycling and agricultural circular economy.ResultsThe total harvest of tomatoes grown with fertilizer with the higher content of glyphosate residue was 35% smaller and the yield of first-class tomatoes 37% lower than that of the control, with lower glyphosate concentration. Two of the five fertilizer companies identified poultry manure as a source of glyphosate contamination. Companies with awareness of pesticide residues reported interest in establishing parameters for pesticide residues.ConclusionsThe extent of glyphosate contamination of recycled fertilizers is unknown, but this study shows that such contamination occurs with negative impacts on crop production. Lack of testing and regulation to ensure that recycled fertilizers are free from harmful levels of glyphosate or other pesticides creates risks for agricultural producers. The issue is particularly acute for certified organic producers dependent on these products, but also for sustainable transitions away from mineral fertilizers in conventional farming. The example from Finland shows that a model of co-production between fertilizer producers and state regulatory agencies to establish safe limits can benefit both fertilizer producers and their customers.

Direct Determination of Glyphosate and Its Metabolites in Foods of Animal Origin by Liquid Chromatography-Tandem Mass Spectrometry.

Glyphosate is the most used herbicide in agriculture. Its major metabolite is AMPA (aminomethylphosphonic acid), but N-acetyl-AMPA and N-acetylglyphosate are also metabolites of interest. For risk assessment, a general residue definition was proposed as the sum of glyphosate, AMPA, N-acetyl-glyphosate and N-acetyl-AMPA, expressed as glyphosate. A confirmatory method for glyphosate in fat, liver and kidneys, as well as a confirmatory method for AMPA and N-acetyl-glyphosate in all matrices, are still missing. In this paper, we present a method for the quantitative determination of glyphosate residues and its metabolites AMPA, N-acetyl-AMPA and N-acetyl-glyphosate by liquid chromatography-mass spectrometry (LC-MS/MS) in adipose tissue, liver, eggs, milk and honey without derivatization. Different chromatographic columns were tested, with the Hypercarb column providing the best results. The analytes were eluted with mobile phases of acidified water with 1.2% formic acid and 0.5% formic acid in acetonitrile. Sample purification procedures were also optimized by varying the solvent extraction mixtures (water, methanol and mixture ψ (methanol, water) = 1:1, each with the addition of 1% formic acid (v/v)), using different sorbents in solid phase extraction (SPE) (polymeric cationic (PCX) and anionic (PAX)) and using dispersive solid phase extraction (dSPE) (C18 and PSA) by modifying the extraction procedures. Finally, the analytes were extracted from the samples with 1% formic acid in water (v/v). Milk and adipose tissue were purified by the addition of dichloromethane, while liver and egg samples were purified by SPE with a mixed cation exchange sorbent and ultrafiltration with cut-off filters. The proposed analytical procedures were validated according to SANTE/11312/2021 guidelines: linearity, limits of quantification, precision and accuracy were determined for all matrices. The limits of quantification (LOQs) ranged from 0.025 to 0.2 mg kg-1. Precision, expressed as relative standard deviation, was <20%, while accuracy, expressed as analytical recovery, ranged from 70% to 120%. During method validation, the measurement uncertainty was estimated to be <50% for all analytes. Good validation parameters according to the SANTE document were achieved for all analytes. Therefore, the method can be considered reliable and sensitive enough for routine monitoring of polar pesticides. The application of the accredited method in routine analysis will provide data that are useful for the re-evaluation of risk assessment studies in foods of animal origin.

How do glyphosate and AMPA alter the microbial community structure and phosphorus cycle in rice-crayfish systems?

Glyphosate, a commonly used organophosphorus herbicide in rice-crayfish cropping regions, may alter regional phosphorus cycle processes while affecting the structure of microbial communities. However, the effects of glyphosate residues on rice-crayfish systems remain unclear. In this study, we assessed the spatial and temporal distribution characteristics of glyphosate and its primary degradation products, as well as the impact mechanisms of glyphosate on microbial communities and the phosphorus cycle in rice-crayfish systems such as paddy fields, breeding ditches and recharge rivers. The detection rates of glyphosate and aminomethylphosphonic acid (AMPA) were 100% in rice-crayfish systems. Concentrations of glyphosate in the water phase and soil/sediment were as high as 0.012 μg/L and 7.480 μg/kg, respectively, and concentrations of AMPA were as high as 17.435 μg/L and 13.200 μg/kg, respectively. Glyphosate concentrations were not affected by rainfall or sampling site, but concentrations of AMPA in the water phase of recharge rivers were affected by rainfall. The glyphosate concentration was significantly and positively correlated with RBG-16-58-14 abundance, and the AMPA concentration was significantly and positively correlated with Actinobacteria and Lysobacter abundance, and negatively correlated with Cyanobacteria abundance (P < 0.05). The highest abundances of phoD, phnK, and ppx genes were found in all soils/sediments. Glyphosate concentration in soil/sediment was significantly and positively correlated with the abundance of phoD gene encoding an organophosphorus-degrading enzyme and ppx gene encoding poly inorganic phosphate (Pi) hydrolase (P < 0.05). In addition, the glyphosate concentration was significantly and positively correlated with the Ca-bonded Pi content (P < 0.05). This implies that glyphosate may promote the production of stable Pi in rice-crayfish systems by increasing the abundance of phoD and ppx genes. The results of this study reveal the impact mechanism of glyphosate on the phosphorus cycle in rice-crayfish systems and provide a basis for the risk assessment of glyphosate.

Glyphosate contamination: implications for honeybee Apis mellifera and consumers in Southeastern Mexico

In a study conducted from June 2021 to May 2022 in two apiaries in southeastern Mexico, levels of glyphosate residues in pollen collected by bee Apis mellifera were analyzed to assess potential risks to both bees and humans. The analysis used an immunoassay method after residue extraction using the QUECHERS method. The results revealed the presence of glyphosate in all samples, with concentrations ranging between 3.71 and 7.29 μg/kg. However, risk analysis, as indicated by the pollen hazard quotient, suggested that these quantities did not pose a serious threat to bees or humans. The levels were within acceptable limits of the acceptable daily intake (ADI), acute reference dose (ARfD) and acceptable operator exposure level (AOEL). In conclusion, although this study did not find any significant association between glyphosate and potential risks for both humans and bees, its persistence in the environment is demonstrated. Glyphosate levels at the study site were low, suggesting minimal risk to both species. However, the wide distribution of glyphosato in the region makes it necessary to emphasize long-term studies to understand the possible chronic effects of the pesticide on all species in the area.

Pesticide residues in boreal arable soils: Countrywide study of occurrence and risks

Large volumes of pesticides are applied every year to support agricultural production. The intensive use of pesticides affects soil quality and health, but soil surveys on pesticide residues are scarce, especially for northern Europe. We investigated the occurrence of 198 pesticide residues, including both banned and currently used substances in 148 field sites in Finland. Results highlight that pesticide residues are common in the agricultural soils of Finland. A least one residue was found in 82% of the soils, and of those 32% contained five or more residues. Maximum total residue concentration among the conventionally farmed soils was 3043 μg/kg, of which AMPA and glyphosate contributed the most. Pesticide residues were also found from organically farmed soils, although at 75–90% lower concentrations than in the conventionally farmed fields. Thus, despite the application rates of pesticides in Finland being generally much lower than in most parts of central and southern Europe, the total residue concentrations in the soils occurred at similar or at higher levels. We also established that AMPA and glyphosate residues in soil are significantly higher in fields with cereal dominated rotations than in grass dominated or cereal–grass rotations. However, risk analyses for individual substances indicated low ecological risk for most of the fields. Furthermore, the total ecological risk associated with the mixtures of residues was mostly low except for 21% of cereal dominated fields with medium risk. The results showed that the presence of mixtures of pesticide residues in soils is a rule rather than an exception also in boreal soils. In highly chemicalized modern agriculture, the follow-up of the residues of currently used pesticides in national and international soil monitoring programs is imperative to maintain soil quality and support sustainable environment policies.

Assessing the Profile of Glyphosate Residues in Maize Grains Sold in the Federal Capital Territory Abuja, Nigeria

The profile of glyphosate residues in maize grains sold in the Federal Capital Territory Abuja (FCT), Nigeria was assessed. Twenty-six maize grain samples of yellow and white morphotypes were collected from some selected markets within the FCT, Abuja. Analytical methods on the pulverized maize grains included solvent extraction using (acetonitrile/water (55:45), clean-up of pesticide residues and their quantification by HPLC/UV as described by the AOAC-QuEChERS method. The results showed that the mean concentration of glyphosate in the maize grains ranged from 0 to 24.30 ± 0.002 mgkg_1 with a mean glyphosate concentration of 3.474 mgkg-1 was detected. Four samples representing 17.86% of the samples collected violated the WHO/FAO CODEX standard of 5.0 mgkg-1 while values recorded for Acceptable Daily Intake (ADI) for all the samples were within an acceptable limit of 0 - 1 mgkg-1. Heath risk index values were &lt;1 suggesting that the consumer populations were not at risk. The high profile of glyphosate residue in maize grains from Gwagwalada Area Council of the FCT is of great concern and needs to be further investigated.

Integrated evaluation of the biological response of the earthworm Eisenia fetida using two glyphosate exposure strategies: soil enriched and soils collected from crops in Southeastern Mexico.

Under laboratory conditions, the toxicological effects of pesticides tend to be less variable and realistic than under field conditions, limiting their usefulness in environmental risk assessment. In the current study, the earthworm Eisenia fetida was selected as a bioindicator for assessing glyphosate toxic effects in two different trials to solve this dilemma. In Trial 1, the worms were exposed for 7 and 14days to concentrations of a commercial glyphosate formulation (1 to 500mg a.i. kg-1) currently used in the field. In Trial 2, the worms were kept in nine soils collected from different plots with crops for 14days of exposure. In both experiments, glutathione S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and acetylcholinesterase (AChE) activities and contents of lipid peroxidation (LPO) were evaluated. In T1, the glyphosate formulation produced a 40% inhibition of AChE activity and a significant increase in GST, SOD, CAT, and GPx activities and LPO contents in E. fetida on day 7. In T2, higher concentrations of glyphosate were detected in the soils of soybean, papaya, and corn (0.92, 0.87, and 0.85mgkg-1), which induced a positive correlation between the levels of glyphosate residues with GST, SOD, CAT, GPx, and LPO and a negative correlation with AChE. These findings indicate that crop soils polluted with glyphosate elicited higher oxidative stress than under laboratory conditions, confirmed by IBRv2, PCA, and AHC analyses.

Gamma irradiation was able to degrade the glyphosate and aminomethylphosphonic acid (AMPA) from drinking water analyzed by LC-MS/MS

Glyphosate is the most widely used systemic herbicide in the world, applied post-emergence to control weeds and is non-selective. However, due to its toxicity to aquatic organisms and high persistence in water, it is necessary to conduct studies on the decontamination of water resources with glyphosate residues and its metabolite aminomethylphosphonic acid (AMPA). The objective of this study was to evaluate the degradation of glyphosate and AMPA in drinking water using gamma irradiation. First, the drinking water sample was found to be free of the herbicide and its metabolite, and then three concentrations of glyphosate and AMPA alone were added (0.5, 5.0, and 50.0 mg L−1). The samples were then exposed to different doses of gamma irradiation (0, 0.5, 1.0, 2.5, 5.0, and 10 kGy) in a cobalt-60 (60Co) source. The procedure was performed at room temperature with a dose of 0.08 kGy h−1 from the irradiator (source power: 215.95 Ci). Glyphosate and AMPA were quantified by Liquid Chromatography coupled to tandem Mass Spectrometry (LC-MS/MS). A pseudo-first order model was fitted from the kinetic study of the degradation of the chemicals. The irradiation doses required to degrade 50% of glyphosate (D0.5 = 8.97, 12.03, and 9.73 kGy) and the value for complete degradation (90%) of the herbicide (D0.9 = 29.82, 39.97, and 32.34 kGy), as the value of the dose constant (k), were 0.0772, 0.0576, and 0.0712 kGy−1 at concentrations of 0.5, 5.0, and 50.0 mg L−1, respectively. The increase in gamma irradiationgradually decreased of glyphosate and AMPA in drinking water. Thus, this study showed that the use of gamma irradiation can decontaminate drinking water with glyphosate and AMPA residues and be used in treatment plants, but it is necessary to use higher doses of radiation.

Glyphosate residues in soil and phosphate fertilizer affect foliar endophytic microbial community composition and phytohormone levels in potato

Glyphosate, the active ingredient of glyphosate-based herbicide (GBH) controls the growth of weeds by inhibiting shikimate pathway, thereby interrupting amino acid biosynthesis in plants. However, several microbes have shikimate pathway and the action of glyphosate on these non-target organisms are ignored. Along with other agrochemicals such as phosphate fertilizers, the action of GBH is further complicated, often varying their mode of action depending on soil type or plant species. To address the impact of GBH and phosphate fertilizer, we simulated agricultural application of GBH and phosphate fertilizer in a field study, investigating the composition of endophytic microbial communities and correlation of phytohormone concentrations with the microbial diversity of potato (Solanum tuberosum). In leaves, glyphosate residues in soil from GBH treatment alone and in combination with phosphate significantly shifted bacterial community whereas phosphate alone and in combination with glyphosate significantly altered the composition of fungal community. There were no significant changes in microbial communities in roots and tubers. Plants treated with GBH showed higher ratios of potentially glyphosate-resistant bacteria, with Xanthomonadaceae and Moraxallaceae being more abundant. Additionally, phytohormone concentrations showed various correlations with bacterial and fungal diversity in different treatments. The study highlights the impact of GBH residues in soil, particularly in combination with phosphate fertilizers on the composition of plant-associated microbial communities. Together with changes in phytohormone concentrations, plant health may be affected. Moreover, future studies could provide insights to whether these agrochemicals influence plant microbiome, leading to changes in phytohormones or vice-versa.

Assessing the Profile of Glyphosate Residues in Maize Grains Sold in the Federal Capital Territory Abuja, Nigeria

The profile of glyphosate residues in maize grains sold in the Federal Capital Territory Abuja (FCT), Nigeria was assessed. Methods Twenty-six maize grains samples of yellow and white morphotypes were collected from some selected markets within the FCT, Abuja. Analytical methods on the pulverized maize grains included solvent extraction using (acetonitrile/water (55:45), clean-up of pesticide residues and their quantification by HPLC/UV as described by AOAC - QuEChERS method. Results The results showed that the mean concentration of glyphosate in the maize grains ranged from 0 to 24.30 ± 0.002 mgkg_1 with a mean glyphosate concentration of 3.474 mgkg-1 was detected. Four samples representing 17.86% of the samples collected violated WHO/FAO CODEX standard of 5.0 mgkg-1 while values recorded for Acceptable Daily Intake (ADI) for all the samples were within an acceptable limit of 0 - 1 mgkg-1. Heath risk index values were &lt;1 suggesting that the consumer populations were not at risk. Conclusion The high profile of glyphosate residue in maize grains from Gwagwalada Area Council of the FCT is of great concern and needed to be further investigated HIGHLIGHTS Maize grains had a low glyphosate residue contamination rate of 96.15% in the FCT, Nigeria. The concentration rate of glyphosate residue in the maize grains range was 0 - 24.3mg/kg Yellow maize grains from Gwagwalada Area Councils had the highest mean concentration of glyphosate residue. Four samples i.e. 15.38% of the maize grains violated the CODEX Maximum Residual limit. The Health Index (HI) for all the maize grains was ˂ 1 and signified no associated risk

Glyphosate Residue Detection Challenges in Complex Matrices: The Paradox and Conundrums

Glyphosate Residue Detection Challenges in Complex Matrices: The Paradox and Conundrums