Aminomethylphosphonic Acid Residues Research Articles

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- and aminomethylphosphonic acid (AMPA)-induced mortality and residues in juvenile brown trout (Salmo trutta f. fario) exposed at different temperatures

BackgroundGlyphosate is a broad-spectrum, non-selective systemic herbicide with a commonly assumed low potential for accumulation in biota. Nevertheless, glyphosate has been shown to bioaccumulate in the tissues of several organisms. To understand the bioconcentration dynamics of glyphosate in fish, brown trout (Salmo trutta forma fario) of different age were exposed to different concentrations of glyphosate, the formulation Roundup® LB Plus, and the major transformation product aminomethylphosphonic acid (AMPA) for two, three, or four weeks at different temperatures in the laboratory. Mortality rates were determined, and tissue samples were collected at the end of the experiment to ascertain concentrations of glyphosate and AMPA residues by liquid chromatography coupled to mass spectrometry (LC–MS/MS).ResultsBrown trout mortality during exposure to glyphosate or AMPA was considerably higher at 15 °C than at 7 °C. Also, a significant increase in glyphosate concentrations in samples containing muscle, head, backbone, and caudal fin tissue with increasing exposure concentrations and temperatures was observed. Six-month-old fish contained more glyphosate per kg wet weight after exposure than ten-month-old fish. The bioconcentration factors (BCFs) for glyphosate and AMPA were much higher at 15 °C than at 7 °C, but in both cases decreased with higher glyphosate concentrations. The BCF for glyphosate formulated in Roundup® was higher than the one for the parent compound. Approximately 30–42% of the organ-absorbed glyphosate and AMPA remained in the tissues even when the fish were kept in clean water lacking the test substances for three weeks after termination of exposure.ConclusionOur study demonstrated that there is an interaction between glyphosate and ambient temperature in terms of toxicity. Further it was shown that increasing concentrations of glyphosate and AMPA in the surrounding media lead to significantly increased concentrations of these substances in brown trout tissues, although neither bioconcentration nor bioaccumulation of glyphosate in animal tissues is expected due to the high water solubility of this chemical. As a consequence, the uptake of glyphosate by humans through the consumption of contaminated edible fish is very likely.

Sensitive detection of herbicide residues using field-amplified sample injection coupled with electrokinetic supercharging in flow-gated capillary electrophoresis.

Residues of glyphosate (GlyP) and its major degradation product, aminomethylphosphonic acid (AMPA), widely exist in the water system and plant products and thus are also present in the bodies of animals and humans. Although no solid evidence has been obtained, the concern about the cancer risk of GlyP is persistent. The measurement of GlyP and AMPA in trace levels is often needed but lacks readily available analytical approaches with detection sensitivity, accuracy and speed. This study aims to develop a simple and robust technique for the sensitive detection of GlyP and AMPA residues in a surface water system with flow-gated capillary electrophoresis (CE). Experimentally, water samples were first fluorogenically derivatized with 4-fluoro-7-nitrobenzofurazan (NBD-F) in a low-conductivity buffer at room temperature, and the mixture was injected and concentrated in the capillary based on field-amplified sample injection (FASI) coupled with electrokinetic supercharging (EKS). This scheme included a step of sample buffer injection upon electroosmotic pumping, where negatively charged analytes were electrophoretically rejected, followed by automatic voltage reversal for FASI-EKS. The detection sensitivity was improved by 296, 444, and 861 times for glufosinate (GluF), AMPA, and GlyP, respectively. The proposed method was validated in terms of accuracy, precision, limits of detection (LODs), and linearity. The LODs were estimated to be 50.0 pM, 5.0 pM, and 10.0 pM for GluF, AMPA, and GlyP, respectively. Its application was demonstrated by measuring GluF and AMPA in water samples collected from a local water system. This study provides an effective approach for the online preconcentration of negatively charged analytes, thus enabling the sensitive detection of herbicide residues in water samples. The method can also be applied to analyze other samples, including biological fluids and plant products, upon appropriate sample preparation such as solid phase extraction of analytes.

Determination of glyphosate and aminomethylphosphonic acid residues in Finnish soils by ultra‐high performance liquid chromatography–tandem mass spectrometry

Glyphosate [N-(phosphonomethyl) glycine] (GLY) adsorbs strongly in Finnish soils. A new method for GLY and its main degradation product, aminomethylphosphonic acid (AMPA) residues in clay soils (Protovertic Luvisol) was developed and validated. A new method was necessary because the previous one required laborious cleaning pre-treatments, and its recovery was quite poor (<40%–70%). In the new method, the earlier method's extraction solvent, 0.1 M potassium hydroxide (KOH), was replaced by more effective 0.6 M KOH. The old post-column high-performance liquid chromatography and fluorescence (HPLC-FLD) method was replaced by the ultra-high performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS) method. Compounds were identified as their fluorenyl methyl chloroformate (FMOC) derivatives by a multiple reaction monitoring (MRM) technique and quantified by an internal standard method utilising multipoint matrix-matched calibration. Glufosinate-ammonium (GLUF) was used to monitor the effectiveness of extraction with good recovery (80–119%). All calibration curves were found to be linear (R2 ≥ 0.98) in the studied calibration range (0.01–3.31 mg kg−1 in fresh soil). The repeatability and reproducibility were 25% and 28% for GLY, and 20% and 24% for AMPA in real research soil samples. The method was effective throughout the calibration range in all the studied Finnish agricultural soils.•An improved method was created to analyse glyphosate (GLY) and AMPA in Finnish clay soil.•The challenge caused by strong GLY adsorption on soil was solved by using multipoint matrix-matched calibration curve samples which were prepared identically with the research samples.•The method performed well in all tested clay, loam and sandy loam soils.

Association of Lifetime Exposure to Glyphosate and Aminomethylphosphonic Acid (AMPA) with Liver Inflammation and Metabolic Syndrome at Young Adulthood: Findings from the CHAMACOS Study.

The prevalence of liver disorders and metabolic syndrome has increased among youth. Glyphosate, the most widely used herbicide worldwide, could contribute to the development of these conditions. We aimed to assess whether lifetime exposure to glyphosate and its degradation product, aminomethylphosphonic acid (AMPA), is associated with elevated liver transaminases and metabolic syndrome among young adults. We conducted a prospective cohort study ( mother-child dyads) and a nested case-control study ( cases with elevated liver transaminases and 91 controls) using data from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS). We measured glyphosate and AMPA concentrations in urine samples collected during pregnancy and at child ages 5, 14, and 18 y from cases and controls. We calculated glyphosate residue concentrations: []. We estimated the amount of agricultural-use glyphosate applied within a radius of every residence from pregnancy to age 5 y for the full cohort using California Pesticide Use Reporting data. We assessed liver transaminases and metabolic syndrome at 18 y of age. Urinary AMPA at age 5 y was associated with elevated transaminases [relative risk (RR) per , 95% confidence interval (CI): 1.06, 1.53] and metabolic syndrome (, 95% CI: 1.38, 3.11). Urinary AMPA and glyphosate residues at age 14 y were associated with metabolic syndrome [ (95% CI: 1.10, 2.93) and (95% CI: 1.03, 3.42), respectively]. Overall, a 2-fold increase in urinary AMPA during childhood was associated with a 14% and a 55% increased risk of elevated liver transaminases and metabolic syndrome, respectively. Living near agricultural glyphosate applications during early childhood (birth to 5 y of age) was also associated with metabolic syndrome at age 18 y in the case-control group (, 95% CI: 1.16, 2.02). Childhood exposure to glyphosate and AMPA may increase risk of liver and cardiometabolic disorders in early adulthood, which could lead to more serious diseases later in life. https://doi.org/10.1289/EHP11721.

Kinetics of glyphosate and aminomethylphosphonic acid sorption onto montmorillonite clays in soil and their translocation to genetically modified corn

The co-occurrence of glyphosate (GLP) and aminomethylphosphonic acid (AMPA) in contaminated water, soil, sediment and plants is a cause for concern due to potential threats to the ecosystem and human health. A major route of exposure is through contact with contaminated soil and consumption of crops containing GLP and AMPA residues. However, clay-based sorption strategies for mixtures of GLP and AMPA in soil, plants and garden produce have been very limited. In this study, in vitro soil and in vivo genetically modified corn models were used to establish the proof of concept that the inclusion of clay sorbents in contaminated soils will reduce the bioavailability of GLP and AMPA in soils and their adverse effects on plant growth. Effects of chemical concentration (1–10 mg/kg), sorbent dose (0.5%-3% in soil and 0.5%-1% in plants) and duration (up to 28 days) on sorption kinetics were studied. The time course results showed a continuous GLP degradation to AMPA. The inclusion of calcium montmorillonite (CM) and acid processed montmorillonite (APM) clays at all doses significantly and consistently reduced the bioavailability of both chemicals from soils to plant roots and leaves in a dose- and time-dependent manner without detectable dissociation. Plants treated with 0.5% and 1% APM inclusion showed the highest growth rate (p ≤ 0.05) and lowest chemical bioavailability with up to 76% reduction in roots and 57% reduction in leaves. Results indicated that montmorillonite clays could be added as soil supplements to reduce hazardous mixtures of GLP and AMPA in soils and plants.

Adsorption and detoxification of glyphosate and aminomethylphosphonic acid by montmorillonite clays.

The co-occurrence of mixtures of glyphosate (GLP) and aminomethylphosphonic acid (AMPA) in contaminated water, soil, sediment, and plants is a cause for concern due to potential threats to the ecosystem and human health. Major routes of exposure include contact with contaminated water and soil and through consumption of crops containing GLP and AMPA residues. Calcium montmorillonite (CM) and acid-processed montmorillonite (APM) clays were investigated for their ability to tightly sorb and detoxify GLP and AMPA mixtures. In vitro adsorption and desorption isotherms and thermodynamic analysis indicated saturable Langmuir binding of both chemicals with high capacities, affinities, enthalpies, and free energies of sorption and low desorption rates. In silico computational modeling indicated that both GLP and AMPA can be readily absorbed onto clay surfaces through electrostatic interactions and hydrogen bonding. The safety and efficacy of the clays were confirmed using well-established living organisms, including an aquatic cnidarian (Hydra vulgaris), a soil nematode (Caenorhabditis elegans), and a floating plant (Lemna minor). Low levels of clay inclusion (0.05% and 0.2%) in the culture medium resulted in increased growth and protection against chemical mixtures based on multiple endpoints. Results indicated that montmorillonite clays may be used to bind mixtures of GLP and AMPA in water, soil, and plants.

Phosphate addition enhances alkaline extraction of glyphosate from highly sorptive soils and aquatic sediments.

Analytical constraints complicate environmental monitoring campaigns of the herbicide glyphosate and its major degradation product aminomethylphosphonic acid (AMPA): their strong sorption to soil minerals requires harsh extraction conditions. Coextracted matrix compounds impair downstream analysis and must be removed before analysis. A new extraction method combined with subsequent capillary electrophoresis-mass spectrometry for derivatization-free analysis of glyphosate and AMPA in soil and sediment was developed and applied to a suite of environmental samples. It was compared to three extraction methods from literature. We show that no extraction medium reaches 100% recovery. The new phosphate-supported alkaline extraction method revealed (1) high recoveries of 70-90% for soils and aquatic sediments, (2) limits of detections below 20 μg kg-1 , and (3) a high robustness, because impairing matrix components (trivalent cations and humic acids) were precipitated prior to the analysis. Soil and sediment samples collected around Tübingen, Germany, revealed maximum glyphosate and AMPA residues of 80 and 2100 μg kg-1 , respectively, with residues observed along a core of lake sediments. Glyphosate and/or AMPA were found in 40% of arable soils and 57% of aquatic sediment samples. In this work, we discuss soil parameters that influence (de)sorption and thus extraction. From our results we conclude that residues of glyphosate in environmental samples are easily underestimated. With its possible high throughput, the method presented here can resolve current limitations in monitoring campaigns of glyphosate by addressing soil and aquatic sediment samples with critical sorption characteristics.

A comprehensive experimental assessment of glyphosate ecological impacts in riparian forest restoration.

Competition with invasive grasses is one of the most important drivers of tree planting failures, especially in tropical forests. A widely disseminated weeding approach has been glyphosate spraying, the most used herbicide globally in forestry and ecosystem restoration. However, glyphosate use in restoration is highly controversial and requires further studies to elucidate its effects on restoration processes and the environment. We evaluated the use of glyphosate in riparian forest restoration and its impacts on tree planting costs, weed control efficiency, planted seedling performance, herbaceous and woody species regeneration, soil bacteria, and environmental contamination, using mowing treatments as a reference and based on a controlled experiment established in the Brazilian Atlantic Forest. Glyphosate spraying reduced by one-half and one-third the accumulated aboveground biomass of, respectively, weeds in general and of the invasive grass Urochloa decumbens compared to mowing treatments, and it reduced the cost by half. The performance of planted tree seedlings was markedly favored by glyphosate spraying compared to mowing treatments, as expressed by improved seedling height (~twice higher), crown area (~5× higher), and basal area (~5× higher); the regeneration of both native woody and ruderal herbaceous plants were also enhanced. Neither glyphosate nor its metabolite Aminomethylphosphonic acid (AMPA) residues were detected in either water runoff or soil samples, but they were found at relatively high concentrations in the runoff sediments (from 1.32 to 24.75 mg/kg for glyphosate and from 1.75 to 76.13 mg/kg for AMPA). Soil bacteria communities differed before and after glyphosate spraying in comparison to mowing plots (without glyphosate). Glyphosate spraying was far more cost effective than mowing for controlling U. decumbens and greatly improved the performance of planted tree seedlings and natural regeneration, while not leaving residues in soil and water. However, the changes in the structure of bacterial communities and high concentration of glyphosate and AMPA residues in runoff sediments highlight the need for caution when using this herbicide in riparian buffers. We present alternatives for reducing glyphosate use and minimizing its risks in tree planting initiatives.

Response of broadleaf and grass cover crop species to soil residues of glyphosate and aminomethylphosphonic acid (AMPA)

AbstractGlyphosate is the most widely used herbicide in the United States; however, concern is escalating about increasing residues of glyphosate and its metabolite aminomethylphosphonic acid (AMPA) in soil. There is a lack of scientific literature examining the response of cover crops to soil residues of glyphosate or AMPA. The objectives of this study were to evaluate the impact of glyphosate or AMPA residues in silty clay loam soil on emergence, growth, and biomass of cover crops, including cereal rye, crimson clover, field pea, hairy vetch, and winter wheat, as well as their germination in a 0.07% (0.7 g L–1) solution of AMPA or glyphosate. Greenhouse studies were conducted at the University of Nebraska–Lincoln to determine the dose response of broadleaf and grass cover crops to soil-applied glyphosate or AMPA. The results indicated that soil treated with glyphosate or AMPA up to 105 mg ae kg–1 of soil had no effect on the emergence, growth, above-ground biomass, and root biomass of any of the cover crop species tested. To evaluate the impact of AMPA or glyphosate on the seed germination of cover crop species, seeds were soaked in Petri plates filled with a 0.7 g L–1 solution of AMPA or glyphosate. There was no effect of AMPA on seed germination of any of the cover crop species tested. Seed germination of crimson clover and field pea in a 0.7 g L–1 solution of glyphosate was comparable to the nontreated control; however, the germination of cereal rye, hairy vetch, and winter wheat was reduced by 48%, 75%, and 66%, respectively, compared to the nontreated control. The results suggested that glyphosate or AMPA up to 105 mg ae kg–1 in silt clay loam soil is unlikely to cause any negative effect on the evaluated cover crop species.

Biomarkers of exposure and effect in the armoured catfish Hoplosternum littorale during a rice production cycle

Fish cultivation in rice fields is a valuable resource in some rural areas of the world. Fish is a source of protein and an additional source of income for local farmers. However, the use of pesticides may impact fish and consumer health. The aim of this study was to evaluate exposure and effect biomarkers in native fish inhabiting a rice field during a production cycle. Samples of fish, water and sediment from a rice field in Santa Fe, Argentina were collected during a cultivation season (at the beginning: November 2017, in the middle: December 2017 and at the end: February 2018). At each sampling period, fish biomarkers of effect (biometric indices, hematological parameters, energy reserves, oxidative stress and neurotoxicity) were assessed together with pesticide screening in water, sediment, and fish samples. Only herbicides were present in water and sediment samples in agreement with land treatment before rice sowing stage, where only herbicides were applied. In general, the greatest water concentrations of bentazone, glyphosate and aminomethylphosphonic acid (AMPA), and the lowest sediment glyphosate and AMPA levels were observed at the beginning of the farming cycle. Fish bioaccumulated AMPA residues at all sampling periods and showed biological responses to cope with a stressful environment. Alterations in hematological parameters, mobilization of energetic reserves and activation of the antioxidant system were detected. However, no oxidative damage nor neurotoxic effects were present along the production cycle. Under a real exposure scenario, the present work demonstrates that biological changes are induced in fish to cope with stressors present in a rice field. Fish-rice coculture is an efficient and ecologically sustainable approach to increase food supplies, and a better understanding of the effect of this particular environment on fish would allow a greater and safer development of this promising productive activity in South American rice producing countries.

Residues of glyphosate and aminomethylphosphonic acid (AMPA) in genetically modified glyphosate tolerant soybean, corn and cotton crops

ABSTRACT: Glyphosate is a broad-spectrum herbicide capable of controlling a wide range of weed. It uses could cause the occurrence of residues in conventional or genetically modified crops. For this purpose, grains (soybean and corn) and cotton seeds were sampled from commercial areas in 2012/2013 to 2017/2018 seasons in different Brazilian agricultural regions to monitor glyphosate residues levels and its metabolite (aminomethylphosphonic acid - AMPA) after different managements. The glyphosate residues levels in genetically modified corn (GM) ranged from no detected (ND) to 0.15 mg kg-1, in GM soybean values ranged from ND to 2.81 mg kg-1 and in GM cotton ranged from ND to 1.78 mg kg-1. AMPA residues levels indicated a correlation with the glyphosate residues. Glyphosate residues levels in soybean and corn grains and cotton seeds were within the Maximum Residue Limits (MRLs) established by ANVISA and Codex Alimentarius.

Influence of arbuscular mycorrhizal fungi on glyphosate dissipation rate in okra cultivated sodic soil of Tamil Nadu

Aim: To elucidate the influence of non target Arbuscular Mycorrhizal (AM) fungi on glyphosate dissipation in okra cultivated sodic soil of Tamil Nadu. Methodology: A field experiment was carried out during Rabi 2017-18 to study the interactive effect of glyphosate and Arbuscular mycorrhizal fungi (AM) on glyphosate dissipation in sodic soil from okra (A. esculentus) grown field. Experiment was laid adopting Randomized Block Design (RBD) with different rates of glyphosate and with and without AM fungi. Glyphosate was applied as pre-plant herbicide 20 days before sowing, and AM biofertilizer was applied as basal before sowing of okra. Soil samples were collected from the field at different time interval after glyphosate application and analysed for glyphosate and Amino Methyl Phosphonic Acid (AMPA) residues. Results: Glyphosate persistence decreased with time and degraded with the mean half-life ranging from 5.09 to 10.35 days by following first order reaction kinetics. AMPA was witnessed from day 1 and increased up to 15th day and followed first order reaction kinetics dissipation with the mean half-life of 8.62 to 13.06 days. Glyphosate and AMPA residues were recorded below detection limit (0.01 mg kg-1) on 45th and 60th days, respectively, in soil. Interpretation: The higher rates of glyphosate showed enhanced persistence of glyphosate and its metabolite AMPA in soil, hence application of AM fungi 100 kg ha-1 with lower glyphosate rate of 6 ml/L can be recommended for okra cultivated sodic soil with the safer waiting period of after 45 days harvest.

Environmental behavior and influencing factors of glyphosate in peach orchard ecosystem

In this paper, several experiments were carried out to study the environmental behavior and influencing factors of glyphosate (PMG) in peach orchard ecosystem. The results of field experiments showed that PMG and its metabolite aminomethylphosphonic acid (AMPA) were detected in peach tree leaves and peach tree fruits, although PMG was only sprayed on the soil. The residues of PMG and AMPA in peach tree leaves were ~0.1 mg/kg and ~0.5 mg/kg and in peach tree fruits were ~0.01 mg/kg and 0.07–0.11 mg/kg, respectively. By conducting a series of laboratory simulation experiments, the environmental factors affecting the degradation of PMG were screened and evaluated. The results showed that PMG metabolized much faster in loess soil than red soil and black soil (with the DT50 of 11.6 days, 62.4 days, and 34.1 days, respectively). By analyzing the basic properties of the soil, we investigated the effects of pH, moisture content, organic matter (exogenous biochar) and ambient temperature using orthogonal experiments, and the results were further confirmed by microbial experiment. The results showed that alkaline conditions (pH = 7.8/9), high water content (25%) and microorganisms could promote the degradation of PMG. Sterile soil environment had a negative impact on the metabolic behavior of PMG to AMPA.

Decreased bioavailability of aminomethylphosphonic acid (AMPA) in genetically modified corn with activated carbon or calcium montmorillonite clay inclusion in soil

The widespread use of pesticides has resulted in detectable residues throughout the environment, sometimes at concentrations well above regulatory limits. Therefore, the development of safe, effective, field-practical, and economically feasible strategies to mitigate the effects of pesticides is warranted. Glyphosate is an organophosphorus herbicide that is degraded to aminomethylphosphonic acid (AMPA), a toxic and persistent metabolite that can accumulate in soil and sediment and translocate to plants. In this study, we investigated the binding efficacy of activated carbon (AC) and calcium montmorillonite (CM) clay to decrease AMPA bioavailability from soil and AMPA translocation to plants. Adsorption isotherms and thermodynamic studies on AC and CM were conducted and showed tight binding (enthalpy values >-20 kJ/mol) for AMPA with high capacities (0.25 mol/kg and 0.38 mol/kg, respectively), based on derivations from the Langmuir model. A hydra assay was utilized to indicate toxicity of AMPA and the inclusion of 1% AC and CM both resulted in 90% protection of the hydra (**p ≤ 0.01). Further studies in glyphosate-contaminated soil showed that AC and CM significantly reduced AMPA bioavailability by 53% and 44%, respectively. Results in genetically modified (GM) corn showed a conversion of glyphosate to AMPA in roots and sprouts over a 10-day exposure duration. Inclusion of AC and CM reduced AMPA residues in roots and sprouts by 47%–61%. These studies collectively indicate that AC and CM are effective sorbents for AMPA and could be used to reduce AMPA bioavailability from soil and AMPA residues in GM corn plants.

Investigation of the presence of glyphosate and its major metabolite AMPA in Greek soils.

Glyphosate is a broad-spectrum, non-selective, post-emergence herbicide that controls weeds by inhibiting their ability to synthesize amino acids. It is characterized by high persistence and adsorption to soil, with its dissipation to be highly correlated to the climatic conditions. After its degradationin soil, aminomethylphosphonic acid (AMPA) is the sole and major metabolite produced, characterized also by high persistence and adsorption. Both substances have the potential to remain in soil rather than move to other environmental compartments. Considering the recent intense debate during the EU renewal of glyphosate along with its wide use, it is apparent that both glyphosate and AMPA require further attention and information on their occurrence and distribution in EU soils. The present study does constitute the first extended soil monitoring survey of glyphosate and AMPA with samples derived during the years 2013-2015, from the highest extent of the Greek territory. Specific attention was given to areas of high agricultural production as well as to urban areas, since glyphosate-containing products are also registered for non-professional uses. The positive samples represented the 36.7% for glyphosate and 44.9% for AMPA, while the detected residues fluctuated from 0.026 to 40.6μgg-1 and from 0.01 to 2.5μgg-1 for glyphosate and AMPA, respectively. Our findings can constitute a basis for the determination of the background concentration levels of glyphosate and its metabolite in the Greek territory. As such, apart from being the first study for glyphosate monitoring in Greece, the most significant highlights recognized in the present work are the following:The high levels of glyphosate and AMPA residues in urban areas that indicate possible misuse of pesticidesThe generally low detection in the main agricultural basins and particularly near water recipientsThe fact that a potential for misuse of herbicides cannot be excluded even in the case of agricultural areas (considering that the maximum detection was in an olive grove and exceeded the model-predicted concentrations by 13 times).

Glyphosate and Aminomethylphosphonic Acid Content in Glyphosate-Resistant Soybean Leaves, Stems, and Roots and Associated Phytotoxicity Following a Single Glyphosate-Based Herbicide Application.

Glyphosate-based herbicide (GBH) applications were reported to induce physiological damages to glyphosate-resistant (GR) soybean, which were mainly attributed to aminomethylphosphonic acid (AMPA). In order to study glyphosate and AMPA dynamics in plants and associated phytotoxic effects, a greenhouse experiment was set where GR soybeans were exposed to GBH (0.7 to 4.5 kg glyphosate ha-1) and sampled over time (2, 7, 14, and 28 days after treatment (DAT)). Hydrogen peroxide content increased 2 DAT, while a decrease was observed for the effective quantum yield (2, 7, 14 DAT), stomatal conductance (2 DAT), and biomass (14 DAT). Glyphosate content was higher in leaves, followed by stems, and then roots. AMPA content tended to increase with time, especially in roots, and the amount of AMPA in roots was negatively correlated to mostly all phytotoxicity indicators. This finding is important since AMPA residues are measured in agricultural soils several months after GBH applications, which could impact productivity in GR crops.

Determination of glufosinate, aminomethylphosphonic acid, and glyphosate residues in farmland soil by post-column addition of alkali using high performance anion exchange chromatography-pulse amperometric detection

A chromatographic method was developed for the determination of glufosinate (GLUF), aminomethylphosphonic acid (AMPA), and glyphosate (GLY) in farmland soil by the post-column addition of alkali using high performance anion exchange chromatography-pulse amperometric detection. Samples were extracted with 2 mmol/L sodium hydroxide solution, then filtered through a 0.22 μm membrane, and purified by a IC-C18 column and IC-Na column. Three target compounds and coexisting ions in the filtered solution were separated on an IonPacAS11-HC anion exchange column (250 mm×4 mm), and were detected by the post-column addition of alkali using pulse amperometric detection. Results showed that GLUF and GLY had good linearity in the range of 20.0-1000 μg/L, and AMPA had good linearity in the range of 5.0-400 μg/L, with correlation coefficients above 0.999. The limits of detection of GLUF, AMPA, and GLY were 0.08, 0.02, and 0.04 mg/kg, respectively, and the recoveries were in the range of 80.2%-106% with RSDs of 0.7%-5.0% (n=6). The method provides strong anti-interference, high sensitivity, and accuracy, and can be adopted simply and quickly; therefore, it is suitable for detecting the residues of GLUF, AMPA, and GLY in farmland soil.

Occurrence of glyphosate and AMPA residues in soy-based infant formula sold in Brazil

ABSTRACTGlyphosate is an herbicide widely used in the world, being applied in several crops, among them soybeans. Recently, glyphosate and its metabolite aminomethylphosphonic acid (AMPA) have been identified as possible contributors to the emergence of various diseases such as autism, Parkinson’s and Alzheimer’s diseases, as well as cancer. The child population-consuming cereal-based foods is the most exposed to the effects of pesticides because of their developmental phase and they have a higher food intake per kilogram of body weight than adults. The presence of glyphosate and AMPA residues in soy-based infant formulas was evaluated during the years 2012–2017, totalising 105 analyses carried out on 10 commercial brands from different batches. Glyphosate and AMPA were determined by liquid chromatography with fluorescence detection after derivatisation reaction. The method was validated and showed accuracy and precision with a limit of quantification (LOQ) of 0.02 mg kg−1. Among those samples that contained levels above the LOQ, the variation of glyphosate residues was from 0.03 mg kg−1 to 1.08 mg kg−1 and for AMPA residues was from 0.02 mg kg−1 to 0.17 mg kg−1. This is the first scientific communication about glyphosate and AMPA contamination in soy-based infant formula in Brazil, The study was conducted under good laboratory practice (GLP) and supported by good scientific practice.

Determination of glyphosate, glufosinate, and main metabolite aminomethylphosphonic acid residues in dry tea using ultra-high performance liquid chromatography-tandem mass spectrometry

A method has been developed for the determination of glyphosate (GLY), glufosinate (GLUF), and the main metabolite aminomethylphosphonic acid (AMPA) residues in dry tea based on ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) coupled with pre-column derivatization. A systematic study of the effects of pretreatment methods including extraction and purification procedures was designed and carried out for the determination of GLY, GLUF, and AMPA. The results indicated that the optimal pretreatment method was as follows:the tea sample was first extracted by water in vortex, and then purified by a cation exchange solid-phase extraction column with the elution of 0.5% (v/v) formic acid aqueous solution. Finally, the eluant was derivatized by 9-fluorenylmethyl chloroformate, and the target compounds were separated on a C18 chromatographic column and analysed by UPLC-MS/MS (ESI+). GLY, GLUF, and AMPA showed good linearity in the range of 1-100 μ g/L, with correlation coefficients above 0.991. The limits of detection and limits of quantification were found to be 0.0160-0.0300 mg/kg and 0.0530-0.100 mg/kg, respectively. The average spiked recoveries of GLY, GLUF, and AMPA varied from 78.3% to 108% at three spiked levels (0.0500, 0.400, and 1.20 mg/kg), while the relative standard deviations ranged from 5.46% to 9.63%. The proposed method was utilized to detect 837 batches of tea samples. The detection ratios of GLY, GLUF, and AMPA were 3.46%, 0.24%, and 4.42%, respectively, while 0.24% of the investigated tea samples had values above maximum residue limits. The developed method is simple, rapid, sensitive, and accurate for the determination of GLY, GLUF, and AMPA in dry tea and may be used for routine analysis.