Aminomethylphosphonic Acid Concentrations 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.

Gestational glyphosate exposure and early childhood neurodevelopment in a Puerto Rico birth cohort

IntroductionN-(phosphonomethyl)glycine, or glyphosate, is a non-selective systemic herbicide widely used in agricultural, industrial, and residential settings since 1974. Glyphosate exposure has been inconsistently linked to neurotoxicity in animals, and studies of effects of gestational exposure among humans are scarce. In this study we investigated relationships between prenatal urinary glyphosate analytes and early childhood neurodevelopment. MethodsMother-child pairs from the PROTECT-CRECE birth cohort in Puerto Rico with measures for both maternal urinary glyphosate analytes and child neurodevelopment were included for analysis (n = 143). Spot urine samples were collected 1–3 times throughout pregnancy and analyzed for glyphosate and aminomethylphosphonic acid (AMPA), an environmental degradant of glyphosate. Child neurodevelopment was assessed at 6, 12, and 24 months using the Battelle Developmental Inventory, 2nd edition Spanish (BDI-2), which provides scores for adaptive, personal-social, communication, motor, and cognitive domains. We used multivariable linear regression to examine associations between the geometric mean of maternal urinary glyphosate analytes across pregnancy and BDI-2 scores at each follow-up. Results were expressed as percent change in BDI-2 score per interquartile range increase in exposure. ResultsPrenatal AMPA concentrations were negatively associated with communication domain at 12 months (%change = −5.32; 95%CI: 9.04, −1.61; p = 0.007), and communication subdomain scores at 12 and 24 months. At 24 months, four BDI-2 domains were associated with AMPA: adaptive (%change = −3.15; 95%CI: 6.05, −0.25; p = 0.038), personal-social (%change = −4.37; 95%CI: 7.48, −1.26; p = 0.008), communication (%change = −7.00; 95%CI: 11.75, −2.26; p = 0.005), and cognitive (%change = −4.02; 95%CI: 6.72, −1.32; p = 0.005). Similar trends were observed with GLY concentrations, but most confidence intervals include zero. We found no significant associations at 6 months. ConclusionsOur results suggest that gestational exposure to glyphosate is associated with adverse early neurodevelopment, with more pronounced delays at 24 months. Given glyphosate's wide usage, further investigation into the impact of gestational glyphosate exposure on neurodevelopment is warranted.

Glyphosate and AMPA in saliva and other traditional human matrices. New findings for less invasive biomonitoring to the exposure to pesticides

Human biomonitoring of the exposure to pesticides is usually performed in biological matrices such as urine and plasma. However, the possibility of using less invasive matrices allows the screening of large number of subjects. The objective of this study was to evaluate the body burden of the exposure to the most widely used herbicide, Glyphosate (GLY), and its main metabolite, the aminomethylphosphonic acid (AMPA), in different populations from the province of Córdoba (Argentina), and to propose the saliva as a matrix for possible implementation in biomonitoring of the exposure to pesticides.Glyphosate and AMPA concentrations were evaluated in urine, plasma, and saliva of subjects occupationally and environmentally exposed to pesticides from one of the most important agricultural areas of Argentina. Gas chromatography coupled to tandem mass spectrometry (MS/MS) was used for the identification and quantification of the analytes.Both GLY and AMPA were quantified in all matrices with higher detection frequency (DF) in the occupationally exposed group than in non-occupationally exposed individuals. Among evaluated matrices, the highest DF and concentration levels of GLY were found in saliva. Moreover, the only statistical difference between groups of subjects were found for GLY and AMPA concentrations in saliva, indicating the possible use of this non-invasive human matrix to evaluate different levels and scenarios of exposure. No significant correlation was found between GLY and AMPA levels in saliva and the traditional matrices (urine and blood) used to measure exposure to pesticides.This is the first report of the presence and concentrations of GLY and AMPA in human saliva samples. Results of the present study are relevant for future biomonitoring of the exposure to GLY, but also to pesticides in general. Saliva deserved further investigation as an alternative, easy, and economical matrix involving less invasive methods for biomonitoring and screenings of large populations.

Delineating the cascade of molecular events in protein aggregation triggered by Glyphosate, aminomethylphosphonic acid, and Roundup in serum albumins

The molecular basis of protein unfolding on exposure to the widely used herbicide, Glyphosate (GLY), its metabolite aminomethylphosphonic acid (AMPA), and the commercial formulation Roundup have been probed using human and bovine serum albumins (HSA and BSA). Protein solutions were exposed to chemical stress at set experimental conditions. The study proceeds with spectroscopic and imaging tools. Steady-state and time-resolved fluorescence (TRF) measurements indicated polarity changes with the possibility of forming a ground-state complex. Atomic force microscopy imaging results revealed the formation of fibrils from BSA and dimer, trimer, and tetramer forms of oligomers from HSA under the chemical stress of GLY. In the presence of AMPA, serum albumins (SAs) form a compact network of oligomers. The compact network of oligomers was transformed into fibrils for HSA with increasing concentrations of AMPA. In contrast, Roundup triggered the formation of amorphous aggregates from SAs. Analysis of the Raman amide I band of all aggregates showed a significant increase in antiparallel β-sheet fractions at the expense of α-helix. The highest percentage, 24.6%, of antiparallel β-sheet fractions was present in amorphous aggregate formed from HSA under the influence of Roundup. These results demonstrated protein unfolding, which led to the formation of oligomers and fibrils.

Investigation on health status of workers exposed to glyphosate

Objective: To analyze the concentrations of glyphosate and its metabolites in occupational exposed workers and their possible effects on human health, so as to provide a reference for improving the safe use of glyphosate and toxicity research. Methods: From April to December 2020, 247 workers directly exposed to glyphosate in 5 enterprises were selected as the contact group, and 237 workers who were not exposed to glyphosate and other pesticides in the same enterprise were selected as the control group. Questionnaire survey and occupational health examination were conducted on objects, and the concentrations of glyphosate and its metabolites in the air of workplaces and biological samples were detected. The correlation between the concentrations and the difference of health examination between the two groups were analyzed. Results: The urine glyphosate concentration (0.022-47.668 mg/L), the rate of exceeding the standard (60.32%, 149/247) and the urine aminomethyl phosphonic acid concentration (<0.010-1.624 mg/L) in the contact group were higher than those in the control group [urine glyphosate concentration (<0.020-4.482 mg/L), the rate of exceeding the standard (2.53%, 6/237) and the urine aminomethyl phosphonic acid concentration (<0.010-0.524 mg/L) ], respectively (P<0.001). The exceeding standard rate of glyphosate concentration in the workplace was 33.67% (33/98). The concentration of glyphosate in the workplace was positively correlated with the concentrations of glyphosate and aminomethylphosphonic acid in urine (r(s)=0.804, 0.238, P<0.001), and the concentration of glyphosate in urine was positively correlated with the concentration of aminomethylphosphonic acid in urine (r(s)=0.549, P<0.001). The alanine aminotransferase (ALT), white cell ratio, creatinine, uric acid, the abnormal rates of ALT and total protein (TP) in the contact group were higher than those in the control group, and TP was lower than that in the control group, the differences were statistically different (P<0.05). The abnormal rates of overall liver function, overall renal function, blood routine test, urine routine test, electrocardiogram, liver B ultrasound and blood lipid in the contact group were significantly higher than those in the control group (P<0.05) . Conclusion: The concentration of glyphosate in the workplace is related to the concentrations of glyphosate and aminomethyl phosphonic acid in the urine of workers, and exposure to glyphosate may have some harmful effects on human health.

Exposure to Low Concentrations of AMPA Influences Morphology and Decreases Survival During Larval Development in a Widespread Amphibian Species.

Glyphosate's primary metabolite, AMPA (aminomethylphosphonic acid), is one of the most widely detected anthropogenic substance in surface waters worldwide. However, ecotoxicological studies on the potential effects of this metabolite at environmental concentrations on wildlife are scarce. Yet, due to its chemical properties, AMPA is likely to affect non-target species. In this study, we investigated sublethal effects of environmental concentrations of AMPA on the larval development of a widespread amphibian species, the spined toad Bufo spinosus. We performed a factorial experiment to study the effect of concentration and the timing of exposure (during embryonic development, larval development or both) to AMPA on the morphology, rate of development and survival of tadpoles. AMPA and timing of exposure interactively affected tadpole size (individuals exposed to AMPA after hatching were transitorily smaller, while individuals exposed to AMPA before hatching were longer), but not duration of development. Most of these effects were linked to exposure during embryonic development. Such effects in individuals exposed during embryonic development solely were long-lasting and persisted until the latest larval stages. Finally, we found that exposure to AMPA after hatching (during the larval stage) increased mortality. Exposure to low environmental concentrations of AMPA could have long-lasting consequences on fitness and population persistence. These findings are especially important to take into account at a time when multiple threats can interact to affect wildlife.

Low detection of glyphosate in rivers following application in forestry.

Glyphosate is the most commonly used herbicide in the world, and is used in agriculture, forestry, and urban settings. In regions with high glyphosate use, such as agricultural, glyphosate and its' major derivative aminomethylphosphonic acid (AMPA) are frequently detected in surface waters. In Canadian forestry glyphosate-based herbicides are used to control vegetation that competes with conifer trees and are applied one to two times during a rotation, leading to infrequent application to the same area. Forestry occurs over a large spatial extent, and the cumulative application in space can lead to a large percentage of the land base receiving an application through time. To assess the frequency and concentration of glyphosate and AMPA in surface waters of a region where forestry is the dominant use sector, we conducted three monitoring programs targeting: (i) immediately after application, (ii) after rainfall, and (iii) cumulative application over a large spatial extent. Across all monitoring programs we collected 296 water samples between August and October from eight river systems over two years and detected glyphosate in one sample at 17 ppb. Glyphosate is not likely present in surface waters during baseflow conditions as a result of applications in forestry. Lack of detection is likely because soil capacity to bind glyphosate remains high due to infrequent applications to the same area, and factors that limit sediment transport to surface waters such as buffers. Additional sampling is needed during other stream conditions, ideally spring freshet, to determine peak concentrations. © 2023 National Research Council Canada. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. Reproduced with the permission of the Minister of Innovation, Science, and Economic Development.

Glyphosate and Aminomethylphosphonic Acid (AMPA) Modulate Glutathione S-Transferase in Non-Tumorigenic Prostate Cells.

Glyphosate (GLY) was developed in the early 1970s and has become the most used broad-spectrum herbicide in the world so far. Its main metabolite is aminomethylphosphonic acid (AMPA), and the accumulation of GLY and its derivative compounds raises some concerns regarding possible health outcomes. In this study, we aimed to evaluate the effects of GLY and AMPA on prostate cell lines by evaluating cell viability, proliferation, gene and protein expression, and cellular pathways involved in the response to oxidative stress. Our results indicated that GLY and AMPA reduced the cell viability of tumorigenic and non-tumorigenic prostate cell lines only at higher concentrations (10 mM GLY and 20 mM AMPA). In contrast, both compounds increased the clonogenicity of non-tumorigenic PNT2 cells, mainly at concentrations below the IC50 (5 mM GLY and 10 mM AMPA). Moreover, treatment of non-tumorigenic cells with low concentrations of GLY or AMPA for 48 h increased GSTM3 expression at both mRNA and protein levels. In contrast, the treatments decrease the GST activity and induced an increase in oxidative stress, mainly at lower concentrations. Therefore, both compounds can cause cellular damage even at lower concentrations in non-tumorigenic PNT2 cells, mainly affecting cell proliferation and oxidative stress.

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.

Toxicity of aminomethylphosphonic acid via the Wnt signaling pathway as a novel mechanism

Glyphosate is one of the most ubiquitous herbicides in the world due to its effective plant removal. However, even though glyphosate and its main metabolite, aminomethylphosphonic acid (AMPA), contaminate the environment and pose threats to humans, their mechanism of toxicity is not well-elucidated. One possible mechanism of action is through the canonical Wnt pathway. This pathway regulates many cellular processes, such as cell fate determination and organogenesis, but its dysfunction can result in cancer. The goal of this study was to assess the toxicity of AMPA and elucidate its effects on Wnt signaling by using planarian regeneration models and molecular docking simulations. To evaluate the toxicity of AMPA, planaria were exposed to environmental concentrations of AMPA and they generally exhibited significantly reduced locomotion, delayed regeneration, and smaller blastema areas. AMPA displayed comparable toxicity to glyphosate and was harmful at low concentrations. To probe the mechanism of action of AMPA and glyphosate, we conducted in silico molecular docking in PyRx to predict its binding to canonical Wnt targets. Both AMPA and glyphosate had moderate simulated binding affinities for proteins in the Wnt pathway, with glyphosate exhibiting stronger affinities than those of AMPA. According to our molecular docking results, AMPA may be capable of binding to Wnt targets. However, it is unclear whether AMPA inhibited or activated Wnt proteins, so it cannot be ascertained that AMPA is definitively carcinogenic. Regardless, AMPA was toxic to planaria, and herbicide application should be more closely regulated to avoid environmental deposition of glyphosate and AMPA.

Exposure of children to glyphosate in Morocco: Urinary levels and predictors of exposure

Glyphosate is one of the most frequently used organophosphorus plant protection products worldwide, and has recently been classified as probably carcinogenic to humans by the International Agency for Research and Cancer (IARC). We aimed to evaluate the urinary levels of glyphosate and its metabolite aminomethylphosphonic acid (AMPA) in Moroccan children, to identify the main predictors and to perform a risk assessment. Data was collected during a cross sectional study of 48 children from an intensive agricultural area. Measurements included a questionnaire on life-style, socio-demographic and herbicide exposures. Urinary glyphosate and AMPA were extracted using solid phase extraction (SPE) and analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Overall, glyphosate and AMPA were detected in 73% and 75% of urine samples, respectively. The mean concentrations were 0.97 μg L−1 (2.06 μg/gcreatinine) for glyphosate and 0.79 μg L−1 (1.52 μg/gcreatinine) for AMPA. Children younger than 5 years had a higher AMPA and glyphosate urine concentration (mean = 2.24 μg L−1; estimation coefficient (EC) = 1.39; 95% CI: 0.54–2.24) (mean = 4.05 μg L−1; EC = 2.92; 95% CI: 1.68–4.15), respectively, than children aged 6–12. Children living near the pesticide spraying fields (<50 m) had 14.91 μg L−1 and 2.35 μg L−1 more glyphosate and AMPA, respectively, than children living in urban counties (95% CI: 8.14–20.91 for glyphosate and 95% CI: 0.55–4.14 for AMPA). AMPA concentration varied significantly with the source of drinking water, AMPA was higher among children that used water from open water sources (mean = 1.49 μg L−1; EC = 2.98; 95% CI/0.67–5.78) compared to those using water from closed water sources. There were also non-significant associations found, such as total household net income, current parental job description, and dietary intake. With the regard to the health risk assessment, estimated daily intake (EDIs), hazard quotient (HQs), and a hazard index (HI) were calculated. The GMs of EDI were 4.38 and 2.26 μg/kg of body weight BW/day for glyphosate and AMPA, respectively. The HQs were calculated considering 0.5 mg/kg BW/day as an acceptable daily intake (ADI), which EFSA has established as a health-based reference value for both analytes. The value obtained were lower than 1, and therefore, low health risk due to glyphosate and AMPA was expected for the target population under the study. This study provides further evidence on factors associated with glyphosate exposure, especially in developing countries.

Urinary concentrations and determinants of glyphosate and glufosinate in pregnant Canadian participants in the MIREC study

BackgroundGlyphosate is the most widely applied herbicide in agriculture. Glufosinate is a broad spectrum herbicide used to manage glyphosate-resistant weeds. Despite the widespread use of these herbicides, biomonitoring data – which inform risk assessment and management – are sparse. ObjectivesTo identify determinants of urinary concentrations of these herbicides and their metabolites in pregnancy. MethodsWe measured urinary concentrations of glyphosate, glufosinate, and their primary metabolites aminomethylphosphonic acid (AMPA) and 3-methylphosphinicopropionic acid (3-MPPA) in a single spot urine specimen collected during the first trimester of pregnancy from the Maternal-Infant Research on Environmental Chemicals (MIREC) study. MIREC recruited about 2000 pregnant women from 10 Canadian cities between 2008 and 2011. We used UItra-Performance Liquid Chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) with sensitive limits of detection to quantify analyte concentrations. We examined urinary concentrations according to maternal sociodemographics, sample collection characteristics, reported pesticide use, and consumption of fruits, vegetables, legumes, and grain products. We used ANOVA models with specific gravity-standardized chemical concentrations as the dependent variable to determine associations with maternal and sample determinants. ResultsAmong women with biobanked urine samples (n = 1829–1854), 74% and 72% had detectable concentrations of glyphosate and AMPA, respectively. In contrast, one and six percent of women had detectable concentrations of glufosinate and 3-MPPA, respectively. The specific gravity-standardized geometric mean (95% CI) concentrations of glyphosate and AMPA were 0.112 (0.099–0.127) μg/L and 0.159 (0.147–0.172) μg/L, respectively. We observed a dose-response relationship between consumption of whole grain bread and higher urinary glyphosate concentrations. Season of urine collection and self-reported pesticide use were not associated with increased concentrations of any analyte. ConclusionsWe detected glyphosate and AMPA in the majority of pregnant women from this predominantly urban Canadian cohort. Diet was a probable route of exposure.

How aminomethylphosphonic acid (AMPA), the main glyphosate metabolite, interferes with chlorophyll biosynthesis?

Aminomethylphosphonic acid (AMPA) has been proposed to interfere with chlorophyll biosynthesis in photoautotrophic organisms – which may explain its greater toxicity to plants in relation to animals. By using the aquatic macrophyte Lemna minor , we investigated the AMPA toxicity and its effects on chlorophyll biosynthesis. Environmentally relevant concentrations (35–50 µg l -1 ) of AMPA reduced L. minor chlorophyll concentration with an EC 10 and EC 50 of 1.3 and 902.9 µg AMPA l -1 after seven days of exposure respectively but did not affect plant fresh weight/growth rate (EC 10 and EC 50 of 178.6/244.4 and 11,922.2/12,513.2 µg AMPA l -1 , respectively). AMPA decreased the activity of glycine decarboxylase (GDC), leading to glycine accumulation and glutamate (Glu) deprivation in plants. The lack of Glu prevents the synthesis of δ-aminolevulinic acid (ALA) in chloroplasts, interfering on chlorophyll synthesis. The negative effect of AMPA on chlorophyll concentration was reversible by supplementing growth media with Glu or ALA. The presence of AMPA in the aquatic ecosystems may contribute to their alteration by its negative effects on photosynthetic organisms through chlorophyll biosynthesis inhibition. Furthermore, we should stress out that AMPA could be toxic for animals and humans due to known toxicity of glycine induced by GDC inhibition. • Environmental relevant concentrations of AMPA reduce chlorophyll concentrations. • AMPA decreased the activity of the enzyme glycine decarboxylase (GDC). • AMPA induces the lack of glutamate and prevents the synthesis of ALA in chloroplasts. • Due to its negative effect on GDC, AMPA could be toxic for animals and humans.

Glyphosate and AMPA have low mobility through different soil profiles of the prosecco wine production area: A monitoring study in north-eastern Italy

Contamination of the environment by glyphosate (GLP) and its metabolite aminomethylphosphonic acid (AMPA) is still of major concern worldwide due to specific interactions among these molecules and soil and water. Two monitoring sites were established in the Prosecco wine production area (Conegliano and Valdobbiadene) in northeastern Italy, which has been included in UNESCO’s World Heritage List since 2019. The study aims to increase the knowledge about GLP dynamics in this area where it has been intensively used by farmers and the potential risk for groundwater pollution is still debated. Each site was equipped with two soil-water monitoring stations consisting of multisensor soil probes and suction cups at three soil depths (10, 30, and 70 cm). Soil and water were sampled for 10 and 6 months, respectively, and analyzed for GLP and AMPA concentrations, for a total of 242 samples to describe their vertical movement and dissipation dynamics. Soil properties, in particular, the different forms of Fe and Al oxide contents, and Freundlich adsorption coefficients were quantified along the soil profile. First attempts showed that glyphosate dissipation time was 36 ± 8 days in Conegliano and Valdobbiadene soils and fully completed in both after 6 months. In contrast, AMPA dissipation dynamic —first described by an original equation—was longer than that of GLP and fully dissipated after almost 300 days. GLP showed a strong binding affinity with clay and Fe and Al chelated to soil organic matter, which likely acted as cation bridges and in turn led to low GLP mobility. GLP and AMPA were mostly detected after heavy rainfall events at 70 cm depth, likely bypassing the porous matrix of the intermediate layers.

Higher proportion of agricultural land use around the residence is associated with higher urinary concentrations of AMPA, a glyphosate metabolite

BACKGROUND &amp;#x26; AIM Pesticides are widely used and there are concerns about their health effects. Little research has been done into the extent to which agricultural land use in the residential surroundings contributes to exposure. We investigated associations between proportion of agricultural land use around the residence and exposure to pesticides. METHODS We included 424 adolescents participating in a Flemish biomonitoring study (FLEHS IV) between 2016 and 2020. Proportions of agricultural land use around the residence were estimated in several buffers (300m, 500m, 1000m and 2000m) after geocoding of residential address. Concentrations of biomarkers of pesticides were measured in urine and adjusted for specific gravity: glyphosate and its metabolite, aminomethyl-phosphonic acid (AMPA); 3-phenoxybenzoic acid (3-PBA); 3,5,6-trichloro-2-pyridinol (TCPy) and 2,4-dichlophenoxy-acetic acid (2,4-D). We categorized pesticide biomarkers in three categories and used ordinal logistic regression models adjusted for sex, season and household education to estimate odds ratios for an interquartile range (IQR) increase of proportion of agricultural land use. We also used binary logistic regression models in which the highest exposure was compared to the lowest exposure and explored effect modification by sex and season. RESULTS We found a significant association between proportion of agricultural land use in 2000m buffer around the residence and levels of urinary AMPA (OR=1.35 for an IQR increase in proportion of agricultural land use around the residence; 95% CI: 1.00-1.83). This association was less pronounced and not statistically significant for other studied pesticides (OR between 0.95 and 1.16). Stratified analysis showed strongest associations of proportion of agricultural land use within 2000m buffer for AMPA among boys (OR=1.89; 95% CI: 1.19-3.04). CONCLUSIONS A higher proportion of agricultural land use around the residence might increase exposure to AMPA. A potential mechanism is wind erosion of contaminated soils. KEYWORDS Pesticide, glyphosate, aminomethyl-phosphonic acid, human biomonitoring, residential land use, built environment

Chronic dietary exposure to a glyphosate-based herbicide results in total or partial reversibility of plasma oxidative stress, cecal microbiota abundance and short-chain fatty acid composition in broiler hens.

Glyphosate-based herbicides (GBHs) are massively used in agriculture. However, few studies have investigated the effects of glyphosate-based herbicides on avian species although they are largely exposed via their food. Here, we investigated the potential reversibility of the effects of chronic dietary exposure to glyphosate-based herbicides in broiler hens. For 42 days, we exposed 32-week-old hens to glyphosate-based herbicides via their food (47 mg/kg/day glyphosate equivalent, glyphosate-based herbicides, n = 75) corresponding to half glyphosate’s no-observed-adverse-effect-level in birds. We compared their performance to that of 75 control animals (CT). Both groups (glyphosate-based herbicides and control animals) were then fed for 28 additional days without glyphosate-based herbicides exposure (Ex-glyphosate-based herbicides and Ex-control animals). Glyphosate-based herbicides temporarily increased the plasma glyphosate and AMPA (aminomethylphosphonic acid) concentrations. Glyphosate and aminomethylphosphonic acid mostly accumulated in the liver and to a lesser extent in the leg muscle and abdominal adipose tissue. Glyphosate-based herbicides also temporarily increased the gizzard weight and plasma oxidative stress monitored by TBARS (thiobarbituric acid reactive substances). Glyphosate-based herbicides temporarily decreased the cecal concentrations of propionate, isobutyrate and propionate but acetate and valerate were durably reduced. The cecal microbiome was also durably affected since glyphosate-based herbicides inhibited Barnesiella and favored Alloprevotella. Body weight, fattening, food intake and feeding behavior as well as plasma lipid and uric acid were unaffected by glyphosate-based herbicides. Taken together, our results show possible disturbances of the cecal microbiota associated with plasma oxidative stress and accumulation of glyphosate in metabolic tissues in response to dietary glyphosate-based herbicides exposure in broiler hens. Luckily, glyphosate-based herbicides at this concentration does not hamper growth and most of the effects on the phenotypes are reversible.

Higher proportion of agricultural land use around the residence is associated with higher urinary concentrations of AMPA, a glyphosate metabolite.

Pesticides, including herbicides, are widely used for agricultural and sanitary reasons and concerns have been raised about their various health effects. Little research has been done into the extent to which agricultural land use in the residential surroundings contributes to (internal) exposure of pesticides. We investigated the associations between the proportion of agricultural land use around the residence and the exposure to pesticides in adolescents in Flanders (Belgium). We included 424 adolescents participating in the fourth Flemish Environment and Health Study (FLEHS IV) between 2016 and 2020. The residential address of all participants was geocoded and the proportion of agricultural land use around the residence was estimated in several buffers (300m, 500m, 1000m and 2000 m). The concentrations of the following biomarkers of pesticides were measured in urine and adjusted for the specific gravity: glyphosate and its metabolite, aminomethyl-phosphonic acid (AMPA); 3-phenoxybenzoic acid (3-PBA); 3,5,6-trichloro-2-pyridinol (TCPy) and 2,4-dichlophenoxy-acetic acid (2,4-D). We categorized the pesticide biomarkers in three categories according to the exposure levels and used ordinal logistic regression models adjusted for sex, season and household education to estimate the odds ratio for an increase in an interquartile range (IQR) of proportion of agricultural land use. We also used binary logistic regression models in which the category of highest exposure was compared to the category of lowest exposure. In addition, we explored potential effect modification by sex and season. We found a significant association between the proportion of agricultural land use in a buffer of 2000 m around the residence and the levels of urinary AMPA divided into three categories (OR=1.35 for an IQR increase in the proportion of agricultural land use around residence; 95% CI: 1.00-1.83). This association was less pronounced and not statistically significant for the other studied pesticides (OR ranging between 0.95 and 1.16). Stratified analysis showed the strongest association of the proportion of agricultural land use within 2000 m buffers for AMPA among boys (OR=1.89; 95% CI: 1.19-3.04). Results using smaller buffers were comparable, but did not reach statistical significance. Our findings suggest that a higher proportion of agricultural land use around the residence might increase exposure to AMPA.

Characterization of glyphosate and AMPA concentrations in the urine of Australian and New Zealand populations

Glyphosate is the most used herbicide globally, but our understanding of human exposure and how different uses affect exposure is not well understood. The aim of this study was to obtain the first data on glyphosate and its primary degradation product aminomethylphosphonic acid (AMPA) concentrations in pooled and individual urine from the Australia and New Zealand region using a sensitive direct injection method and compare results with studies from elsewhere. Pooled urine samples from the Australian general population (n = 125 pools representing >1875 individuals) and individual urine samples (n = 27) from occupationally exposed New Zealand farmers were analysed by LC-MS/MS. Glyphosate was detected above the LOD (0.20–1.25 μg/L) in 8 % of the Australian population pooled urine samples with most detections in the 45–60 years age group. Furthermore, glyphosate (0.85 to 153 μg/L) and AMPA (0.50 to 3.35 μg/L) were detected in 96 % and 33 % of farmers, respectively. The maximum glyphosate urine concentration was 1.7 times above the recommended acceptable daily intake (ADI), when assuming a urinary excretion rate of 1 %. The pooled sampling and analysis approach proved effective for rapid large-scale screening of populations and could be used to determine where targeted and more specific individual sampling may be required.

Herbicide residues in Australian grain cropping soils at sowing and their relevance to crop growth

Herbicides are used extensively in Australian grain cropping systems. Despite occasional observations of herbicide-induced phytotoxicity, there is little information on the persistence and carryover of multiple herbicide classes in cropping soils and the risk to subsequent crops. Two soil surveys were conducted, in 2015 (n = 40) and 2016 (n = 42), across different Australian grain cropping fields prior to sowing of winter crops, and soil samples analysed for herbicide residues (16 analytes in 2015 and 22 analytes in 2016). Samples in 2015 were taken at two depths (0–10 cm and 10-30 cm), whilst samples in 2016 were taken in topsoil (0–10 cm) only, but from two discrete locations in each field. Our research in both years found at least one herbicide (or herbicide metabolite) residue at all sites, with a median of 6 analytes detected in 2015 and 7 analytes detected in 2016. The most frequently detected residues were glyphosate and its primary breakdown product aminomethylphosphonic acid (AMPA), in 87 and 100%, respectively, of topsoil (0–10 cm) samples in 2015, and 67 and 93% of samples in 2016. The median concentration of glyphosate in 2015 was 0.12 mg kg−1, while AMPA was 0.41 mg kg−1. In 2016, median concentrations of glyphosate and AMPA were 0.22 mg kg−1 and 0.31 mg kg−1. Residues of 2,4-dichlorophenoxyacetic acid, trifluralin and diflufenican were also detected in >40% of topsoil samples in both seasons, but with median concentrations of <0.05 mg kg−1. A literature review found limited availability of phytotoxicity thresholds for major grain crops exposed to soilborne herbicide residues. A risk assessment using available thresholds suggested that although up to 29% of fields contained trifluralin residues that could constrain cereal crop growth, and 24% of fields contained residues of phenoxy or sulfonylureas that could affect dicotyledonous crops, the majority of these fields when planted with tolerant crops would be unlikely to be affected by herbicide residues. More work is required to ascertain the spatial distribution, bioavailability and phytotoxicity of residues and residue mixtures to enable a more accurate agronomic risk assessment.