Sulfamethoxazole Transformation by Heat-Activated Persulfate: Linking Transformation Products Patterns with Carbon and Nitrogen Isotope Fractionation

Environmental Science & Technology, Год журнала: 2025, Номер unknown

Опубликована: Март 10, 2025

Sulfamethoxazole (SMX) is a frequently detected antibiotic in groundwater, raising environmental concerns. Persulfate oxidation used for micropollutant removal. To investigate SMX transformation by persulfate, experiments were conducted using heat-activated persulfate at pH 3, 7, and 10. TP269a (SMX-hydroxylamine) TP178 identified as the dominant TPs across levels. The exclusive formation of 4-nitroso-SMX, 4-nitro-SMX, TP518 3 highlighted role SO4•- attacking NH2. At 7 10, 3A5MI emerged TP. Carbon isotopic fractionation (εC = -1.3 ± 0.5‰, -1.1 0.4‰, 0.3‰ 10) remained consistent levels, caused involving C-S bond cleavage. An inverse nitrogen isotope (εN +0.68 0.11‰) was associated with SO4•--induced single-electron transfer. Conversely, normal 10 -0.27 0.04‰) N-H cleavage H abstraction through HO• N-S indicated that pathway involved reactions, accounting 74%. Overall, results highlight potential CSIA to elucidate pathways.

Язык: Английский

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Stable isotope composition of pesticides in commercial formulations: The ISOTOPEST database

Chemosphere, Год журнала: 2024, Номер 352, С. 141488 - 141488

Опубликована: Фев. 16, 2024

By assessing the changes in stable isotope compositions within individual pesticide molecules, Compound Specific Isotope Analysis (CSIA) holds potential to identify and differentiate sources quantify degradation environment. However, environmental application of CSIA is limited by general lack knowledge regarding initial isotopic composition active substances commercially available formulations used farmers. To address this limitation, we established a database aimed at cataloguing disseminating signatures commercial expand use CSIA. Our study involved collection 25 analytical standards 120 from 23 manufacturers. Subsequently, 59 were extracted, each their substance was analyzed for both δ

Язык: Английский

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Avoiding Interferences in Advance: Cyclodextrin Polymers to Enhance Selectivity in Extraction of Organic Micropollutants for Carbon Isotope Analysis

Analytical Chemistry, Год журнала: 2023, Номер 95(20), С. 7839 - 7848

Опубликована: Май 11, 2023

Compound-specific isotope analysis (CSIA) of organic water contaminants can provide important information about their sources and fate in the environment. Analyte enrichment from remains nonetheless a critical yet inevitable step before measurement. Commercially available solid-phase extraction (SPE) sorbents are inherently nonselective leading to co-extraction concurrent dissolved matter (DOM) turn analytical interferences, especially for low-occurring contaminants. Here, we (i) increased selectivity by synthesizing cyclodextrin polymers (α-, β-, γ-CDP) as SPE sorbents, (ii) assessed applicability carbon selection pesticides, (iii) compared them with commonly used commercial sorbents. Extraction β-CDP significantly reduced backgrounds gas chromatography-isotope ratio mass spectrometry (GC-IRMS) enhanced sensitivity factor 7.5, which was further confirmed lower carbon-normalized CDOM/Canalyte ratios corresponding extracts derived (DOC) liquid chromatography-tandem (LC-MS/MS) analysis. Gibbs free energies adsorption demonstrated weak competition between DOM analyte on three CDPs. No isotopic fractionation (Δδ13C within ± 0.3‰) observed investigated pesticides after using an sorbent covering range concentrations (5-500 μg L-1), flow velocities (5-40 cm min-1), regeneration (up six times). The present study highlights benefit selecting innovative avoid interferences advance. This strategy combination existing cleanup approaches offers new prospects CSIA at field tens hundreds nanograms per liter.

Язык: Английский

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Direct Phototransformation of Sulfamethoxazole Characterized by Four-Dimensional Element Compound Specific Isotope Analysis

Environmental Science & Technology, Год журнала: 2024, Номер 58(23), С. 10322 - 10333

Опубликована: Июнь 1, 2024

The antibiotic sulfamethoxazole (SMX) undergoes direct phototransformation by sunlight, constituting a notable dissipation process in the environment. SMX exists both neutral and anionic forms, depending on pH conditions. To discern photodegradation of at various levels differentiate it from other transformation processes, we conducted under simulated sunlight 7 3, employing product (TP) compound-specific stable isotope analyses. At 7, primary TPs were sulfanilic acid 3A5MI, followed sulfanilamide (5-methylisoxazol-3-yl)-sulfamate, whereas photoisomer was dominant product, 3A5MI. Isotope fractionation patterns revealed normal 13C, 34S, inverse 15N fractionation, which exhibited significant differences between 3. This indicates pH-dependent phototransformation. hydrogen isotopic composition remained during levels. Moreover, there no variation observed 33S two levels, indicating that mass-independent remains unaffected changes pH. analysis main single-element suggests varying combinations bond cleavages different values, resulting distinct fractionation. Conversely, dual-element values did not significantly differ, cleavage several bonds parallel. Hence, prudent interpretation these systems is warranted. These findings highlight potential multielement characterizing SMX, thereby facilitating evaluation its natural attenuation through photolysis

Язык: Английский

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Artificial intelligence SoS framework for sustainable agricultural production

Computers and Electronics in Agriculture, Год журнала: 2023, Номер 213, С. 108182 - 108182

Опубликована: Сен. 3, 2023

Язык: Английский

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Involving degradation products provides a new perspective of diffuse pollution assessment of atrazine with a modified mass balance approach

Journal of Hazardous Materials, Год журнала: 2025, Номер 487, С. 137169 - 137169

Опубликована: Янв. 9, 2025

Язык: Английский

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Comment on egusphere-2024-2840

Опубликована: Янв. 13, 2025

Abstract. The prediction of pesticide dissipation on the catchment scale through hydrological models often encounters challenges due to limited availability field data capable distinguishing between degradative and non-degradative processes. This limitation complicates calibration frequently results in equifinality, impeding reliable forecast persistence soil its transportation from agricultural plots outlet. study examines benefits integrating Compound-Specific Isotope Analysis (CSIA) improve predictive accuracy assessing off-site transport at scale. research was conducted a 47-ha crop catchment, focusing widely used pre-emergence herbicide S-metolachlor. A novel conceptual model, named PIBEACH, developed predict daily rivers, incorporating changes carbon isotopic signatures (δ¹³C) targeted during degradation. Parameter model uncertainties were estimated using Generalized Likelihood Uncertainty Estimation (GLUE) method. inclusion S-metolachlor concentrations topsoil their associated δ¹³C values resulted more than two-fold reduction related degradation half-life six metrics transport. Moreover, indicates that moderate yet sampling effort can effectively identify hot-spots hot-moments when isotope fractionation is integrated into model. In summary, incorporation CSIA distributed holds potential alleviate parameter therewith significantly improving our ability dynamics

Язык: Английский

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Dissipation of the insecticide profenofos in tropical agricultural soils (Berambadi catchment, South India): insight from compound-specific isotope analysis (CSIA)

Journal of Hazardous Materials, Год журнала: 2025, Номер unknown, С. 137428 - 137428

Опубликована: Янв. 1, 2025

Язык: Английский

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Fate and degradation of methoxychlor in a contaminated aquifer: insights from dual carbon-chlorine isotope analysis and isomeric fraction

Journal of Hazardous Materials, Год журнала: 2025, Номер 488, С. 137447 - 137447

Опубликована: Янв. 29, 2025

Язык: Английский

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Stable Carbon and Sulfur Isotopic Compositions of Per- and Polyfluoroalkyl Substances

Environmental Science & Technology Letters, Год журнала: 2025, Номер 12(2), С. 216 - 221

Опубликована: Янв. 31, 2025

Prolific use, mobility, and chemical stability make assessing the fate transport of per- polyfluoroalkyl substances (PFAS) particularly complex. New analytical techniques will be required to distinguish between PFAS different origins trace their through natural systems. This study assesses stable carbon (δ13C) sulfur (δ34S) isotopic signatures from sources. Bulk elemental analyzer-isotope ratio mass spectrometry compound-specific gas chromatograph-isotope (GC-IRMS) methods were used measure δ13C δ34S values multiple compounds various vendors production lot numbers. originating with numbers species showed distinct over a wide range (−52.8‰ −26.9‰). Results indicate that GC-IRMS could utilized determine composition present at concentrations typical environmental samples. Coupling data co-contaminant or isomer help further differentiate The development new forensics tools such as these necessary elucidate source in systems may inform remediation pollution prevention protocols for PFAS.

Язык: Английский

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