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1.
Chemosphere ; 286(Pt 3): 131972, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34426278

RESUMO

Bifunctional cathodes have attracted widespread interest in the heterogeneous electro-Fenton (hetero-EF) process. In this study, the bifunctional composite cathode co-modified with N-doped carbon CoFe alloy (CoFe@NC) and carbon nanotubes (CNTs), designated as CoFe@NC-CNTs/CNTs/NF, integrating hydrogen peroxide (H2O2) synthesis and catalysis, was prepared for efficient degradation of atrazine (ATZ) under the near-neutral condition (pHi = 5.9). The morphology properties, crystal structure, microstructures, and elemental composition were determined. The influences of current density, initial pH value, different anions, and water matrix on the removal of ATZ were systematically studied. In the hetero-EF process, high removal efficiencies of ATZ can be achieved over the broad pH range (3-9) under the current density of 4.5 mA cm-2. The removal efficiency of ATZ remained at 90.2 ± 0.3% after 8 cycles under the near-neutral condition (pHi = 5.9). Radical quenching tests and EPR spectra have verified that both free radical pathways such as superoxide anion (O2·-) and hydroxyl radical (·OH) and non-radical pathway such as singlet oxygen (1O2) contributed to ATZ removal. The degradation pathways and catalytic mechanism were proposed. Toxicity evaluation and Escherichia coli growth test showed that the toxicity gradually decreased during the degradation process. This work provided a new thought for developing an efficient and stable bifunctional cathode to construct an in-situ hetero-EF system for pollutants removal over the wide pH range.


Assuntos
Atrazina , Nanotubos de Carbono , Poluentes Químicos da Água , Eletrodos , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Níquel , Oxirredução , Poluentes Químicos da Água/análise
2.
Sci Total Environ ; 807(Pt 1): 150609, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34619212

RESUMO

Triazine herbicides are widely used in agricultural production, and large amounts of herbicide residue enter the ocean through surface runoff. In this study, the toxicities of the triazine herbicides atrazine, prometryn and terbutryn (separately and mixed) to Phaeodactylum tricornutum were investigated. The EC50 values of atrazine, prometryn and terbutryn were 28.38 µg L-1, 8.86 µg L-1, and 1.38 µg L-1, respectively. The EC50 of an equitoxic mixture of the three herbicides was 0.78 TU, indicating that they had synergistic effects. The equitoxic mixture accumulated in P. tricornutum, which damaged chloroplast and mitochondria structures and significantly decrease the biomass, levels of key cellular components (such as chlorophyll a (chl a), carbon (C) and nitrogen (N) content, fatty acid content) and the effective photochemical quantum yield of photosystem II (PSII, ∆Fv/Fm). The mixture also downregulated key genes in the light response (PsbD, PetF), dark response (PGK, PRK), tricarboxylic acid (TCA) cycle (CS, ID, OGD, and MS) and fatty acid synthesis (FABB, SCD, and PTD9). P. tricornutum partially alleviates the effects of the mixture on photosynthesis and fatty acid synthesis by upregulating PetD, PsaB, RbcL and FabI expression. The triazine herbicide mixture reduced the biomass and nutritional value of marine phytoplankton by inhibiting photosynthesis and energy metabolism.


Assuntos
Atrazina , Herbicidas , Atrazina/toxicidade , Clorofila A , Herbicidas/toxicidade , Valor Nutritivo , Fotossíntese , Prometrina , Triazinas/toxicidade
3.
Chemosphere ; 288(Pt 1): 132480, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34626663

RESUMO

Passive uptake of contaminants of emerging concern (CECs) and its relationship with physicochemical properties, such as lipophilicity (LogKow), ionization behavior (pKa), distribution coefficient (LogDow) and transpiration rate are scarcely studied. In the current study, hydroponically grown corn (Zea mays) was exposed to carbamazepine (CBZ), fluoxetine (FLX), gemfibrozil (GBZ), triclosan (TRI) and atrazine (ATZ)) at environmentally relevant concentrations (20 µg/L each one). Plant tissue concentrations of CECs were determined several times over 21 days. Eighteen plants were used, nine exposed to the CECs and nine untreated. Whole plants were harvested at 7, 14 and 21 days and separated into roots, stem, leaf and male bud flower (only at 21 days). Hydroponic solution was maintained at pH 5.5 throughout the study. CECs concentrations in the exposure solution and tissues were determined by LC-MS/MS. ATZ metabolites desisopropylatrazine (DIA) and desethylatrazine (DEA) were determined by LC-DAD. In shoot tissues, CBZ, FLX and ATZ were detected, while TRI and GBZ were detected only in roots. Root concentrations were related with LogKow (R2ROOT = 0.415). Leaf and stem concentrations of CBZ, FLX and ATZ were linked with LogKow and strongly linked with pKa. Transpiration was related with CBZ and ATZ in shoot, but not related with FLX shoot levels. Neutral compounds such as CBZ (pKa = 13.94; 100% neutral) and ATZ (pKa = 1.6; 85% neutral) were taken up passively with transpiration. Root accumulation was related with CECs lipophilicity, while translocation and bioaccumulation in shoot were not only related with lipophilicity, but also with CECs ionization behavior and transpiration.


Assuntos
Atrazina , Poluentes Químicos da Água , Cromatografia Líquida , Transpiração Vegetal , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise , Zea mays
4.
Chemosphere ; 287(Pt 1): 132104, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34523452

RESUMO

The extensive use and environmental persistence of atrazine has resulted in its ubiquitous occurrence in water resources. Some reports have described atrazine bioaccumulation and biodegradation pathways in terrestrial plants, but few have done so in aquatic macrophytes. Thus, in this study, we aimed to analyze morphological changes, uptake, translocation and bioaccumulation patterns in tissues of the aquatic macrophyte Typha latifolia (cattail) after long-term atrazine exposure and to determine the presence of atrazine biodegradation metabolites, desethylatrazine (DEA) and desisopropylatrazine (DIA), in tissues. Plants were hydroponically exposed to 20 µg/L atrazine (18 exposed and 18 non-exposed) for 7, 14, 21, 28, 35 and 42 days. Plants were separated into root, rhizome, stem, and lower, middle and upper leaf sections. Atrazine was analyzed by LC-MS/MS and DIA and DEA by LC-DAD. Plants showed reductions in weight (after 21 days) and transpiration (after 28 days), both symptoms of chronic phytotoxicity. The distribution of atrazine within tissues, expressed as concentration levels (µg/kg dry weight), was as follows: middle leaf (406.10 ± 71.77) = upper leaf (339.15 ± 47.60) = lower leaf (262.43 ± 7.66) = sprout (274.53 ± 58.1) > stem (38.63 ± 7.55) = root (36.00 ± 3.49) = rhizome (26.15 ± 3.96). In submerged tissues, DEA and DIA were detected at similar concentrations. In leaves, DIA was the main metabolite identified. Results indicated that atrazine was taken up from roots to shoots and induced phytotoxicity effects that reduced the translocation to shoots. Typha likely is able to biodegrade atrazine via different metabolic pathways.


Assuntos
Atrazina , Herbicidas , Typhaceae , Atrazina/análise , Atrazina/toxicidade , Bioacumulação , Biodegradação Ambiental , Cromatografia Líquida , Herbicidas/toxicidade , Espectrometria de Massas em Tandem
5.
Chemosphere ; 287(Pt 4): 132370, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34592209

RESUMO

The aim of this study is to produce an electrode that can be used in H2O2 production and Electro-Fenton (EF) process by an effective, cheap, and easy method. For this reason, a superhydrophobic electrode with a higher PTFE ratio and high thickness was produced with a simple press. The produced electrode was used in the production of H2O2 and mineralization of Atrazine. First, the effect of pH, cathode voltage, and operation time on H2O2 production was evaluated. The maximum H2O2 concentration (409 mg/L), the highest current efficiency (99.80%), and the lowest electrical energy consumption (3.16 kWh/kg) were obtained at 0.8 V, 7.0 of pH, and 120 min, and the stability of the electrode was evaluated up to 720 min. Then, the effects of the operational conditions (pH, cathode voltage, operating time, and catalyst concentration) in electro-Fenton were evaluated. The fastest degradation of Atrazine (>99%) was obtained at 2.0 V, 3.0 of pH, and 0.3 mM of Fe2+ in 15 min. In the final part of the study, the degradation intermediates were identified, and the characterization of the electrode was evaluated by SEM, XRD, FT-IR, tensiometer, potentiostat, and elemental analyzer.


Assuntos
Atrazina , Poluentes Químicos da Água , Carbono , Eletrodos , Peróxido de Hidrogênio , Oxirredução , Oxigênio , Fuligem , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise
6.
Sci Total Environ ; 803: 149972, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34482142

RESUMO

The present study assesses the spatial distribution and temporal trends of the water dissolved phase (WDP), suspended particulate matter (SPM) and sediment partitioning of atrazine (ATR) and its metabolites in the Volturno River estuary. The load contribution of ATR and its metabolites in this river to the Central Mediterranean Sea was estimated. Samples were collected in 10 sampling sites during the four seasons. The total concentrations of ATR and DPs detected ranged from 18.1 to 105.5 ng L-1 in WDP, from 4.5 to 63.2 ng L-1 in SPM, and from 4.6 to 18.6 ng g-1 in sediment samples, indicating high levels of these pollutants. Structural equation model and the ratio study indicated that the relationship between sediment and WDP pollutants occurred through the SPM. The pollutants load at the Volturno River in its mouth was evaluated in about 30.4 kg year-1, showing that this river is an important source of these analytes through discharge into Central Mediterranean Sea. Principal component analysis indicated that ATR and its metabolites pollution moves from Volturno River mouth southward and increased in the rainy season. The desethylatrazine-to-atrazine ratio was higher than 0.5 for all samples analyzed, indicating an historical discharge and a long residence time of ATR in sediment about two decades after its ban, and classifying ATR as a nonpoint source contaminant. This study makes up the first record of ATR and its metabolites in superficial water of Southern Italy and provides helpful data as starting point for future studies.


Assuntos
Atrazina , Poluentes Químicos da Água , Atrazina/análise , China , Monitoramento Ambiental , Estuários , Sedimentos Geológicos , Rios , Poluentes Químicos da Água/análise
7.
J Agric Food Chem ; 70(1): 87-98, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34936355

RESUMO

Atrazine (ATZ) is an agricultural pesticide for controlling field weeds. ATZ accumulates in many crops, posing high risks to crop production and food safety. Characterizing one of the novel rice MT genes named Oryza sativa atrazine-responsive methyltransferase (OsARM) showed that the expression of OsARM was associated with DNA demethylation (hypomethylation) in its promoter region. The enhancement of OsARM expression was manifested by the attenuated symptoms of ATZ toxicity including better growth and lower ATZ accumulation in plants. The promoted capacity of detoxification was confirmed by transgenic rice overexpression OsARM lines and also functionally proved by CRISPR-Cas9 knockout mutants. The transgenic lines accumulate more ATZ metabolites in rice and lower concentrations in the growth environment, pointing out that ATZ metabolism or degradation can be intensified. The ATZ-induced DNA demethylation is an important hallmark representing the epigenetic mechanism, which is required for the extra OsARM expression to facilitate ATZ disappearance in rice and the environment.


Assuntos
Atrazina , Herbicidas , Oryza , Praguicidas , Atrazina/toxicidade , Epigênese Genética , Herbicidas/toxicidade , Metiltransferases/genética , Oryza/genética
8.
Anal Chim Acta ; 1189: 339186, 2022 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-34815052

RESUMO

The spatial heterogeneity of environmental systems makes sampling at multiple locations crucial to provide complete and representative information. The on-site application of an extraction technique simplifies the sampling logistics, increasing sample integrity during transportation and storage. This article presents a portable, simple, and low-cost device capable of performing the simultaneous on-site extraction of several environmental water samples. The device consists of a small electric motor integrated into the plastic cap of a conventional glass bottle and operated with a portable battery. The electric motor provides stirring to a novel magnetic sorptive phase based on the deposition of hydrophilic-lipophilic balance (HLB) particles over a magnetic tape. The use of open technology makes the device globally affordable. In this first approach, the isolation and preconcentration of atrazine and simazine have been selected as proof of concept. Using an internal standard made unnecessary the adjustment of the ionic strength before the extraction, thus simplifying the analytical procedure. Under the optimum conditions and using direct infusion mass spectrometry as the instrumental technique, detection limits as low as 15 ng/L were obtained. The precision calculated at three different levels was better than 8.3%. The accuracy, calculated with spiked samples, indicates the applicability of the approach for environmental water analysis.


Assuntos
Atrazina , Poluentes Químicos da Água , Interações Hidrofóbicas e Hidrofílicas , Fenômenos Magnéticos , Espectrometria de Massas , Poluentes Químicos da Água/análise
9.
Artigo em Inglês | MEDLINE | ID: mdl-34948848

RESUMO

Recent studies observed a correlation between estrogen-related cancers and groundwater atrazine in eastern Nebraska counties. However, the mechanisms of human exposure to atrazine are unclear because low groundwater atrazine concentration was observed in counties with high cancer incidence despite having the highest atrazine usage. We studied groundwater atrazine fate in high atrazine usage Nebraska counties. Data were collected from Quality Assessed Agrichemical Contaminant Nebraska Groundwater, Parameter-Elevation Regressions on Independent Slopes Model (PRISM), and water use databases. Descriptive statistics and cluster analysis were performed. Domestic wells (59%) were the predominant well type. Groundwater atrazine was affected by well depth. Clusters consisting of wells with low atrazine were characterized by excessive groundwater abstraction, reduced precipitation, high population, discharge areas, and metropolitan counties. Hence, low groundwater atrazine may be due to excessive groundwater abstraction accompanied by atrazine. Human exposure to atrazine in abstracted groundwater may be higher than the estimated amount in groundwater.


Assuntos
Atrazina , Água Subterrânea , Humanos , Nebraska/epidemiologia , Poços de Água
10.
Environ Monit Assess ; 193(12): 827, 2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34796399

RESUMO

Inclusion of pesticide monitoring data in pesticide risk assessment is important yet challenging for several reasons, including infrequent or irregular data collection, disparate sources procedures and associated monitoring periods, and interpretation of the data itself in a policy context. These challenges alone, left unaddressed, will likely introduce unintentional and unforeseen risk assessment conclusions. While individual water quality monitoring programs report standard operating procedures and quality control practices for their own data, cross-checking data for duplicated data from one database to another does not routinely occur. Consequently, we developed a novel quality control and assurance methodology to identify errors and duplicated records toward creating an aggregated, single pesticide database toward use in ecological risk assessment. This methodology includes (1) standardization and reformatting practices, (2) data error and duplicate record identification protocols, (3) missing or inconsistent limit of detection and quantification reporting, and (4) site metadata scoring and ranking procedures to flag likely duplicate records. We applied this methodology to develop an aggregated (multiple-source), national-scale database for atrazine from a diverse set of surface water monitoring programs. The resultant database resolved and/or removed approximately 31% of the total ~ 385,000 records that were due to duplicated records. Identification of sample replicates was also developed. While the quality control and assurances methodologies developed in this work were applied to atrazine, they generally demonstrate how a properly constructed and aggregated single pesticide database would benefit from the methods described herein before use in subsequent statistical and data analysis or risk assessment.


Assuntos
Atrazina , Praguicidas , Atrazina/análise , Monitoramento Ambiental , Praguicidas/análise , Controle de Qualidade , Padrões de Referência
11.
Ecotoxicol Environ Saf ; 226: 112862, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34624533

RESUMO

OBJECTIVE: To investigate the mechanisms of ATR-induced dopaminergic toxicity by microglia activation and the response of the Keap1/ Nrf2- ARE signaling pathway. METHODS: Wistar rats were treated with 50, 100 and 200 mg/kg ATR and BV-2 microglia cells were treated with 50, 100 µM ATR or 100 ng/mL LPS, respectively. Rats behavioral responses and histopathological changes were monitored. Immunohistochemical and immunofluorescence analysis detected Iba-1 and TH+ cells in rats. Keap1/Nrf2-ARE signaling-related proteins and inflammatory factors from BV-2 cells and rats were detected using ELISA, Western blot and Real-time PCR. RESULTS: After ATR treatment, the grip strength of Wistar rats was significantly decreased, and anxiety were clearly observed. TH+ neurons were reduced, however, the number of microglia cells and Iba-1 levels were increased clearly in SN. The release of ROS, TNF-α and IL-Iß were increased, and levels of SOD and GSH-Px were significantly decreased. Keap1 mRNA expression and protein levels were decreased, while nuclear Nrf2 mRNA expression and protein levels were both increased in vivo and in vitro. CONCLUSION: ATR could significantly activate microglia and exacerbate neurotoxicity and neuroinflammation, leading to accelerate dopaminergic neuron cell death by inhibiting Keap1/Nrf2-ARE signaling pathway.


Assuntos
Atrazina , Fator 2 Relacionado a NF-E2 , Animais , Neurônios Dopaminérgicos/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Microglia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais
12.
J Agric Food Chem ; 69(42): 12527-12540, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34657419

RESUMO

The rapid development of nanotechnology influences the developments within the agro-sector. An example is provided by the production of nanoenabled pesticides with the intention to optimize the efficiency of the pesticides. At the same time, it is important to collect information on the unintended and unwanted adverse effects of emerging nanopesticides on nontarget plants. Currently, this information is limited. In the present study, we compared the effects of a nanoformulation of atrazine (NPATZ) and the nonencapsulated atrazine formulation (ATZ) on physiological responses, defense mechanisms, and nutrient displacement in lettuce over time with the applied concentrations ranging from 0.3 to 3 mg atrazine per kg soil. Our results revealed that both NPATZ and ATZ induced significant decreases in plant biomass, chlorophyll content, and protein content. Additionally, exposure to NPATZ and ATZ caused oxidative stress to the lettuce plant and significantly elevated the activities of the tested ROS scavenger enzymes in plant tissues. These results indicate that NPATZ and ATZ cause distinct adverse impacts on lettuce plants. When comparing the adverse effects in plants after exposure to NPATZ and ATZ, no obvious differences in plant biomass and chlorophyll content were observed between NPATZ and ATZ treatments at the same exposure concentration regardless of exposure duration. An enhanced efficiency of the active ingredient of the nanopesticide as compared to the conventional formulation was observed after long-term exposure to the high concentration of NPATZ, as it induced higher impacts on plants in terms of the end points of the contents of protein, superoxide anion (O2̇-), and MDA, and the activities of stress-related enzymes as compared to the same concentration of ATZ. Furthermore, exposure to both NPATZ and ATZ disrupted the uptake of mineral nutrients in plants, and the differences in the displacement of nutrients between the NPATZ and ATZ treatments depended on the element type, plant organ, exposure concentration, and time. Overall, the application dose of a nanopesticide should balance their increased herbicidal efficiency with the long-term adverse effects in order to maximize the desired impact while minimizing adverse impacts; only then will we be able to understand the potential impact of nanopesticides on the environment.


Assuntos
Atrazina , Herbicidas , Atrazina/farmacologia , Atrazina/toxicidade , Mecanismos de Defesa , Herbicidas/farmacologia , Herbicidas/toxicidade , Alface , Nutrientes
13.
Ecotoxicol Environ Saf ; 227: 112886, 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34673406

RESUMO

Atrazine (ATR) is a widely used herbicide that can induce the degeneration of dopaminergic (DAergic) neurons in the substantia nigra, resulting in a Parkinson's disease-like syndrome. Despite the high risk of environmental exposure, few studies have investigated strategies for the prevention of ATR neurotoxicity. Our previous studies demonstrated that ATR can impair mitochondrial function, leading to metabolic failure. Cells maintain mitochondrial quality through selective autophagic elimination, termed mitophagy. Soybean isoflavones (SI) possess multiple beneficial bioactivities, including preservation of mitochondria function, so it was hypothesized that SI can protect neurons against ATR toxicity by promoting mitophagy. Pretreatment of SH-SY5Y neurons with SI prevented ATR-induced metabolic failure and cytotoxicity as assessed by intracellular ATP, Na+-K+-ATPase activity, mitochondrial membrane potential, and cell viability assays. The neuroprotective efficacy of SI was superior to the major individual components genistein, daidzein, and glycitein. Ultrastructural analyses revealed that ATR induced mitochondrial damage, while SI promoted the sequestration of damaged mitochondria into autophagic vesicles. Soybean isoflavones also induced mitophagy as evidenced by upregulated expression of BNIP3/NIX, BEX2, and LC3-II, while co-treatment with the mitophagy inhibitor Mdivi-1 blocked SI-mediated neuroprotection and prevented SI from reversing ATR-induced BEX2 downregulation. Furthermore, BEX2 knockdown inhibited SI-induced activation of the BNIP3/NIX pathway, mitophagy, and neuroprotection. These findings suggest that SI protects against ATR-induced mitochondrial dysfunction and neurotoxicity by activating the BEX2/BNIP3/NIX pathway.


Assuntos
Atrazina , Isoflavonas , Atrazina/toxicidade , Neurônios Dopaminérgicos , Isoflavonas/farmacologia , Proteínas de Membrana , Mitofagia , Soja
14.
Environ Sci Process Impacts ; 23(11): 1791-1802, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34709265

RESUMO

Knowledge of direct and indirect photodegradation of pesticides and associated isotope fractionation can help to assess pesticide degradation in surface waters. Here, we investigated carbon (C) and nitrogen (N) isotope fractionation during direct and indirect photodegradation of the herbicides atrazine and S-metolachlor in synthetic agriculturally impacted surface waters containing nitrates (20 mg L-1) and dissolved organic matter (DOM, 5.4 mgC L-1). Atrazine and S-metolachlor were quickly photodegraded by both direct and indirect processes (half-lives <5 and <7 days, respectively). DOM slowed down photodegradation while nitrates increased degradation rates. The analysis of transformation products showed that oxidation mediated by hydroxyl radicals (HO˙) predominated during indirect photodegradation. UV light (254 nm) led to significant C and N isotope fractionation, yielding isotopic fractionation values εC = 2.7 ± 0.3 and 0.8 ± 0.1‰, and εN = 2.4 ± 0.3 and -2.6 ± 0.7‰ for atrazine and S-metolachlor, respectively. In contrast, photodegradation under simulated sunlight led to negligible C and slight N isotope fractionation, emphasizing the effect of the radiation wavelengths on the isotope fractionation induced by direct photodegradation. Altogether, these results highlight the importance of using simulated sunlight to obtain environmentally-relevant isotopic fractionation values and to distinguish photodegradation and other dissipation pathways in surface waters.


Assuntos
Atrazina , Poluentes Químicos da Água , Acetamidas , Isótopos , Fotólise , Água , Poluentes Químicos da Água/análise
15.
Chemosphere ; 285: 131544, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34710964

RESUMO

Ruthenium (RuIII)-activated peroxymonosulfate (the RuIII/PMS process) is one of the most efficient PMS-based advanced oxidation processes for the abatement of organic contaminants. Here we interestingly found that phenyl methyl sulfoxide (PMSO) was significantly oxidized to phenyl methyl sulfone (PMSO2) in the RuIII/PMS process at the pH range of 3.0-6.0, with the conversion ratio of ΔPMSO to ΔPMSO2 was close to 100%, which favored the dominance of high-valent ruthenium-oxo species (RuVO) instead of the widely-recognized radicals (i.e, hydroxyl radical and sulfate radical). Scavenging experiments further indicated that RuVO was unreactive to tert-butyl alcohol, but could be scavenged by methanol and dimethyl sulfoxide. Besides, sulfamethoxazole, acetaminophen, carbamazepine, diclofenac, 2,4,6-trichlorophenol were readily degraded in the RuIII/PMS process, but atrazine, ibuprofen, benzoic acid and 4-nitrobenzoic acid were barely removed, suggesting the high selectivity of RuVO species. This study enriched the understandings on the mechanism of RuIII-mediated PMS activation and the nature of RuVO species.


Assuntos
Atrazina , Peróxidos , Radical Hidroxila , Oxirredução
16.
Environ Sci Technol ; 55(20): 13891-13901, 2021 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-34586806

RESUMO

Multielement isotope fractionation studies to assess pollutant transformation are well-established for point-source pollution but are only emerging for diffuse pollution by micropollutants like pesticides. Specifically, chlorine isotope fractionation is hardly explored but promising, because many pesticides contain only few chlorine atoms so that "undiluted" position-specific Cl isotope effects can be expected in compound-average data. This study explored combined Cl, N, and C isotope fractionation to sensitively detect biotic and abiotic transformation of the widespread herbicides and groundwater contaminants acetochlor, metolachlor, and atrazine. For chloroacetanilides, abiotic hydrolysis pathways studied under acidic, neutral, and alkaline conditions as well as biodegradation in two soils resulted in pronounced Cl isotope fractionation (εCl from -5.0 ± 2.3 to -6.5 ± 0.7‰). The characteristic dual C-Cl isotope fractionation patterns (ΛC-Cl from 0.39 ± 0.15 to 0.67 ± 0.08) reveal that Cl isotope analysis provides a robust indicator of chloroacetanilide degradation. For atrazine, distinct ΛC-Cl values were observed for abiotic hydrolysis (7.4 ± 1.9) compared to previous reports for biotic hydrolysis and oxidative dealkylation (1.7 ± 0.9 and 0.6 ± 0.1, respectively). The 3D isotope approach allowed differentiating transformations that would not be distinguishable based on C and N isotope data alone. This first data set on Cl isotope fractionation in chloroacetanilides, together with new data in atrazine degradation, highlights the potential of using compound-specific chlorine isotope analysis for studying in situ pesticide degradation.


Assuntos
Atrazina , Água Subterrânea , Herbicidas , Biodegradação Ambiental , Isótopos de Carbono/análise , Fracionamento Químico , Cloro/análise , Herbicidas/análise
17.
Environ Toxicol Pharmacol ; 88: 103749, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34547448

RESUMO

We developed phospho-ERK1/2 ELISA for human and rainbow trout liver cells, employing HepG2 and RTL-W1 cell lines as models. The assay was applied to detect changes in ERK1/2 activity for nine chemicals, added over a wide concentration range and time points. Cell viability was measured to separate ERK1/2 regulation from cytotoxicity. Perfluorooctane sulfonate and carbendazim did not change ERK1/2 activity; influence on ERK1/2 due to cytotoxicity was indicated for tributyltin and cypermethrin. Mancozeb, benzo[a]pyrene, and bisphenol A stimulated ERK1/2 up to ∼2- (HepG2) and 1.5 (RTL-W1)-fold, though the kinetics differed between chemicals and cell lines. Bisphenol A and benzo[a]pyrene were the most potent concentration-wise, altering ERK1/2 activity in pM (HepG2) to nM (RTL-W1) range. While atrazine and ibuprofen increased ERK1/2 activity by ∼2-fold in HepG2, they did not initiate an appreciable response in RTL-W1. This assay proved to be a sensitive, medium- to high-throughput tool for detecting unrecognized ERK1/2-disrupting chemicals.


Assuntos
Fígado/citologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Ácidos Alcanossulfônicos/toxicidade , Animais , Atrazina/toxicidade , Compostos Benzidrílicos/toxicidade , Benzimidazóis/toxicidade , Benzo(a)pireno/toxicidade , Carbamatos/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fluorcarbonetos/toxicidade , Humanos , Ibuprofeno/toxicidade , Maneb/toxicidade , Oncorhynchus mykiss , Fenóis/toxicidade , Fosforilação/efeitos dos fármacos , Piretrinas/toxicidade , Compostos de Trialquitina/toxicidade , Zineb/toxicidade
18.
Water Res ; 205: 117663, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34555742

RESUMO

Selective removal of atrazine (ATZ) in wastewater and clarification of the degradation intermediate-toxicity correlation are of great importance. A newly molecularly imprinted, {001} facets-exposed TiO2 (MI-TiO2,001) photoanode with strong catalytic and selective ability was designed. ATZ was selectively removed from pesticide wastewater, reaching 1.9 µg L-1, approximately 1/10 of the concentration achieved with nonselective treatment. This selective removal originated from the preferential adsorption and enrichment of ATZ onto MI-TiO2,001. The highly specific recognition relied on the halogen bond and strong hydrogen bond formed between the Cl atom and triazine ring π orbital of ATZ and the surface -OH group of MI-TiO2,001 as well as the recognition of MI-TiO2,001 to the shape and size of ATZ. The specific interaction leads to different accumulations of intermediates. The correlation of intermediate and toxicity was also discussed. Aquatic toxicity was rapidly reduced through the direct dealkylation path, and due to the accumulation of highly toxic 2­hydroxy-4-ethylamino-6-isopropylamino-s-triazine, there will be transient fluctuations via the dechlorination-hydroxylation path first. The final product was identified as nearly nontoxic cyanuric acid, the selective accumulation of which indicated that there was almost 100% removal of aquatic toxicity and cytotoxicity with only 9.8% removal of total organic carbon. This work provides new insight into the correlation of pollutant degradation intermediates and changes in toxicity.


Assuntos
Atrazina , Herbicidas , Praguicidas , Poluentes Químicos da Água , Atrazina/análise , Catálise , Águas Residuárias , Água , Poluentes Químicos da Água/análise
19.
Int J Mol Sci ; 22(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34360708

RESUMO

BACKGROUND: exposure to environmental contaminants has been linked to an increased risk of neurological diseases and poor outcomes. Chemical name of Atrazine (ATR) is 6-chloro-N-ethyl-N'-(1-methylethyl)-1,3,5-triazine-2,4-diamine, and it is the most commonly used broad-spectrum herbicide in agricultural crops. Several studies have demonstrated that ATR has the potential to be harmful to the brain's neuronal circuits. Until today nobody has explored the effect of ATR inhalation on young and aged mice. METHODS: young and aged mice were subject to 25 mg of ATR in a vehicle made with saline and 10% of Dimethyl sulfoxide (DMSO) every day for 28 days. At the end of experiment different behavioral test were made and brain was collected. RESULTS: exposure to ATR induced the same response in terms of behavioral alterations and motor and memory impairment in mice but in aged group was more marked. Additionally, in both young and aged mice ATR inhalations induced oxidative stress with impairment in physiological antioxidant response, lipid peroxidation, nuclear factor kappa-light-chain-enhancer of activated B cells (nf-κb) pathways activation with consequences of pro-inflammatory cytokines release and apoptosis. However, the older group was shown to be more sensitive to ATR inhalation. CONCLUSIONS: our results showed that aged mice were more susceptible compared to young mice to air pollutants exposure, put in place a minor physiologically response was seen when exposed to it.


Assuntos
Envelhecimento/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Atrazina/efeitos adversos , Encéfalo/metabolismo , Administração por Inalação , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Atrazina/farmacologia , Encéfalo/patologia , Inflamação/induzido quimicamente , Inflamação/metabolismo , Inflamação/patologia , Masculino , Camundongos
20.
J Vet Diagn Invest ; 33(6): 1163-1167, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34384305

RESUMO

Ten of 40 cows died within 48 h of gaining access to a barn in which various chemicals were stored. Some of the surviving cows exhibited drooling, muscle tremors, and agitation. Postmortem examinations of 2 cows were performed in the field, and revealed nonspecific, moderate-to-severe pulmonary congestion. Liver and rumen contents, each from a different cow, were analyzed using a qualitative, multi-residue GC-MS method validated for the detection of pesticides and other chemical analytes. Using this method, extracts from the liver and rumen content samples were compared to atrazine (neat standard) and matrix-matched, control samples fortified with atrazine. GC-MS analysis detected atrazine at 215 m/z (NIST match >97%) with a retention time of ~13 min in liver and rumen content samples from our case. Detection of atrazine in the samples from the cows in this herd, combined with the clinical history, indicate that atrazine toxicity was the likely cause of clinical signs and death observed in this herd.


Assuntos
Atrazina , Animais , Atrazina/toxicidade , Bovinos , Feminino , Cromatografia Gasosa-Espectrometria de Massas/veterinária
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