Atrazine In Water Research Articles

Ultra-preconcentration of common herbicides in aqueous samples using solid phase extraction combined with dispersive liquid–liquid microextraction followed by HPLC–UV

An analytical method, solid-phase extraction combined with dispersive liquid–liquid microextraction (SPE–DLLME), was established to extract and determine the herbicides in aqueous samples. In this method, herbicides were adsorbed from a large volume of aqueous samples (100 mL) into 500 mg functionalized octadecyl silica (C18) sorbent. After the elution of the desired compounds from the sorbent by using acetone, DLLME technique was performed on the obtained solution. Under the optimum conditions, the calibration graphs are linear in the range of 0.02–10 µg L−1 and limits of detection (LODs) are in the range of 0.003–0.006 µg L−1. The relative standard deviations (RSDs, for 0.50 µg L−1 of 2,4-D and alachlor, and 1.00 µg L−1 of atrazine in water) are in the range of 6.1–8.1% (n = 5). The SPE–DLLME provided a high enrichment factor (1725–2065) for herbicides.

A bio-functions integration microcosm: Self-immobilized biochar-pellets combined with two strains of bacteria to remove atrazine in water and mechanisms

A self-immobilization method for microorganisms was developed based on fungal pellets. Generally, pellets have some problems such as cell leakage, cell loading limitation and low mechanical strength. Therefore, biochar was applied to overcome these disadvantages. Atrazine degradable microorganism Arthrobacter sp. ZXY-2 was immobilized by Aspergillus niger Y3 pellets. After adding biochar with optimal dosage (0.006 g biochar for 0.3 g pellets with ZXY-2), the self-immobilized biomixture (SIB) removed 50 mg /L atrazine rapidly within 1 h, which was 61% higher compared to pellets without biochar. The kinetic adsorption results showed that the biosorption of biochar by pellets followed a pseudo-second-order kinetic model. The ATZ removal ability and reusability of SIB were significantly increased by biochar. The results showed that the addition of biochar could enhance the connection between ZXY-2 and pellets based carrier, and the favorable biodegradation pH of ZXY-2 changed to 6 and 10. Several analyses such as ζ-potential measurements, FTIR, XPS, SEM-EDS, and elemental analyses were performed to evaluate the mechanism of action of SIB. To enhance the ATZ degradation by single strain, Agrobacterium, sp WL-1 was isolated and added. The metabolic pathways and their function complementation were studied. Furthermore, a biomass integration model for wastewater treatment was proposed herein.

Self-immobilized biomixture with pellets of Aspergillus niger Y3 and Arthrobacter. sp ZXY-2 to remove atrazine in water: A bio-functions integration system

The microorganism Arthrobacter. ZXY-2 exhibits excellent degradation efficiency for atrazine in free cells. However, its poor fixability makes it hard to be kept and recycled in water. To conquer the problem, this work employed mycelial pellets of Aspergillus niger Y3 to immobilize ZXY-2, which formed a self-immobilized biomixture (SIB) to remove atrazine. SIB could completely degrade 57.3 mg/L atrazine within 10 h. The SIB exhibited the highest degradation efficiency at pH = 7 and 40 °C. Degradation of atrazine with initial concentrations of 57.3 mg/L and 17.5 mg/L was described well by zero and first-order reaction kinetics, respectively. The recycling experiments demonstrated that SIB could be recycled for 5 batches. The results of SEM, FT-IR, and zeta potential analysis showed that porous structure, functional groups, and electronegativity of SIB all contributed to its stable formation. Therefore, this study demonstrates that SIB could be formed stably and could remove atrazine efficiently.

Electrospun tin (IV) oxide nanofiber based electrochemical sensor for ultra-sensitive and selective detection of atrazine in water at trace levels

Atrazine, a class 3a carcinogen, is a pesticide of chloro triazine family and is known to severely affect the human endocrine system upon consumption. The toxic effects of atrazine cause damage not only to the humans but also to animals and plants. In lieu of the detrimental effects of atrazine on environment, it is essential to develop a sensor platform capable of its detection in water. Here, we propose ultrasensitive electrochemical detection of atrazine using electrospun SnO2 nanofibers. In this study, the nanofibers have been characterized using Field Emission Spectroscopy, X-ray diffraction analysis (XRD), X-ray photoelectron spectroscopy (XPS), UV-Vis-NIR spectroscopy and Fourier transform infrared spectroscopy (FTIR). Using a label-free transduction, we have detected atrazine in fairly low concentrations, with the limit of detection being 0.9 zM and the sensitivity being 4.11 (μA/μM)/cm2, in a wide dynamic detection range varying from 1 zM to 1 μM. Furthermore, we have reported atrazine detection in trace levels in spiked real time water samples, which is an essential step in ensuring that the sensing platform can be deployed for practical applications. In addition to this, the sensor exhibits excellent selectivity, reasonable stability (when stored at 4 °C), and good interference-resistance.

Efficient degradation of atrazine by LaCoO3/Al2O3 catalyzed peroxymonosulfate: Performance, degradation intermediates and mechanism

In this study, LaCoO3/Al2O3 (LCA) was utilized as a heterogeneous catalyst to activate peroxymonosulfate (PMS) to degrade atrazine (ATZ). The structural properties of the catalysts were characterized by SEM, EDS, XRD, XPS and TPD. The effects of some key parameters (i.e., loadings of LCA, ATZ concentration, catalyst dosage, PMS concentration, initial pH and coexisting ions) were optimized. In addition, under the optimal conditions of 100 mg/L 23LCA, 100 mg/L PMS and initial solution pH 6.8, the removal rate and mineralization efficiency of ATZ (5 mg/L) reached 100% and 30.8%, respectively. The superiority of the 23LCA/PMS system was verified by two controlled experiments. After three cycles of experiments, the degradation effect of ATZ was within an acceptable range. The degradation intermediates of ATZ were detected by UPLC-QTOF-MS/MS, and the possible degradation pathway of ATZ was proposed. In addition, the presence of SO4− and HO was identified by quenching experiments and SO4− was verified as the predominant radical. Finally, based on the comprehensive analysis, a reasonable reaction mechanism of the 23LCA/PMS system was proposed. In a word, these results indicate that LCA can act as a highly efficient heterogeneous catalyst to activate PMS to degrade ATZ in water.

Quick and Easy Modification of Glassy Carbon Electrodes with Ionic Liquid and Tetraruthenated Porphyrins for the Electrochemical Determination of Atrazine in Water

AbstractAtrazine is a pesticide used to control broadleaf weeds, however its wide distribution and its high persistence in the soil and in surface waters has resulted in a public and environmental health problem. Present results shows the design, construction and characterization of glassy carbon electrodes modified with tetrarutenated metalloporphyrin (M=Ni (II) and Zn (II)) and 1‐butyl‐3‐methylimidazolium bis (trifluoromethylsulfonyl) imide, BMIMNTF2. The modification was reproducible and sensitive for the electrochemical detection of atrazine in neutral media. The detection limit was 230 nM when using GC/BMIMNTF2/ZnTRP and 540 nM with GC/BMIMNTF2/NiTRP, meaning that his methodology can be a feasible and inexpensive way to detect atrazine in trace levels.

Development of Ultra-sensitive Method for Determination of Trace Atrazine Herbicide in Environmental Water Using Magnetic Graphene Oxide-Based Solid-Phase Extraction Coupled with Dispersive Liquid-Liquid Microextraction Prior to Gas Chromatography-Mass Spectrometry

Atrazine is one of the most widely used herbicides and has caused much concern about its toxic effects on human and ecosystem. In the present work, a new and efficient method for ultra-trace determination of atrazine in water was developed, using magnetic graphene oxide-based solid-phase extraction combined with dispersive liquid-liquid microextraction, followed by gas chromatography-mass spectrometric determination. The effects of sample pH, contact time, type and volume of elution solvent and extraction solvent, desorption time, and salt addition on the extraction efficiency of atrazine were examined and optimized. Under the optimum conditions, an enrichment factor of 1033 and a detection limit of 0.6 ng L−1 for atrazine were achieved. The developed method was applied to the detection of atrazine in river water, lake water, pond water, and groundwater samples, with spiked recovery of 96–102% and RSD of 2.9–10.5%. Therefore, the proposed method allows proper monitoring of trace atrazine in various environmental waters.

Rapid preparation of molecularly imprinted polymers by custom-made microwave heating for analysis of atrazine in water.

The rapid preparation of an atrazine-imprinted polymer in a cost-effective custom-made microwave reactor was demonstrated. The polymerization reaction was accelerated by microwave heating, and the preparation time was greatly shortened (to 1 h). The resulting polymer was successfully applied as solid-phase extraction adsorbent for the selective extraction and preconcentration of atrazine in environmental water samples. The binding capacity of the polymer was 1.11mg/g polymer. The polymer provided selectivity with higher recovery of atrazine than of other interfering related contaminants. The proposed method had good limits of detection and quantitation at 0.20 and 0.60ng/mL, respectively. The recoveries were from 83 to 89% at two spiking levels, with relative standard deviations less than 5%. This method was successfully applied to determine the atrazine levels in environmental water samples.

Robust nanocatalyst membranes for degradation of atrazine in water

Solid membranes for degradation of emerging contaminants such as atrazine is of significant interest for water engineering applications. In this study, nanocatalyst particles have been anchored on vertically-aligned carpet-like arrays of carbon nanotubes (CNT) grown on porous carbon foams. This hierarchical architecture combines the advantages of highly surface-active nanoparticles with the robust and reusable structural advantage of porous solid membranes suitable for water treatment devices. Three types of palladium-based nano-catalytic surfaces have been investigated: metallic palladium (Pd), Pd nanoparticle with a layer of oxide (PdO-coated Pd), and Pd nanoparticle coated with thin film of silver (Ag-Pd). Their catalytic activities have been compared by analysing the degradation rate of atrazine in water. It is noted that all three catalysts show high levels of atrazine degradation, with the PdO-coated nanoparticles showing the highest kinetics. These results demonstrate that hierarchical hybrid architectures can provide compact and powerful surface-active materials such as adsorbents and catalytic degradation devices in future water treatment applications.

Synthesis and visible-light photocatalytic activity of In,S-TiO2@rGO nanocomposite for degradation and detoxification of pesticide atrazine in water

The visible-light activated In,S-TiO2@rGO nanocomposite was prepared using an innovative ultrasonic-assisted solvothermal method. The products were characterized by XRD, FT-IR, Raman, SEM, HRTEM, TGA and UV–Vis DRS. A considerable red shift in absorption edge of TiO2 was observed after co-doping with In and S. Co-doping of TiO2 with In and S elements and compositing with rGO significantly enhanced its visible-light photocatalytic activity. The complete degradation and 95.5% mineralization of 20 mg/L atrazine (ATZ) was attained at 3.0 mol% of In, 1 mol% of S and 5 wt% of rGO within 20 min. Reaction with OH at the surface of catalyst was the main mechanism contributed in degradation of ATZ in the developed photocatalytic process. As-made In,S co-doped TiO2@rGO nanocomposite could preserve its catalytic activity during four consecutive recycles for the ATZ removal process. The cytotoxicity of fresh and photocatalytic-treated ATZ solutions assessed using the human hepatic cells (HepG2) indicated that ATZ solution in the developed PCO process could be considerably detoxified.

Photo-degradation of atrazine in water using UV and investigating its by-products

Photo-degradation of atrazine in water using UV and investigating its by-products

Determination of atrazine isotherms on agricultural soils

For determination of atrazine isotherms in agricultural soils of Fars Province, composite soil samples from 0 to 5 cm depth with textures of silty clay loam, clay loam and loam were collected. In order to form the atrazine isotherms, 10, 50 and 100 µg atrazine g−1 soil was added to the soil samples. Soluble atrazine in water:soil ratios of 10:1, 50:1 and 200:1 was measured after 3-h shaking. Finally, for each cases of applied atrazine, water extractable atrazine was determined and quantified using gas chromatography instrument. The results indicated that there was a linear relationship between the logarithms of water extractable atrazine and added atrazine for different water:soil ratios. A general equation of WEA = K(WS) α (AA) β is obtained experimentally between water extractable atrazine, µg g−1(WEA), and added atrazine, µg g−1 (AA), where K, α and β are absorption constants; WS is the water:soil ratio, g g−1. For the loam, silty clay loam and clay loam soil textures, the α were 0.49, 0.23 and 0.13, respectively, the β were 0.55, 0.806 and 0.21, respectively, and the K were 1.44, 0.78 and 25.38, respectively.

Presence of Agricultural Herbicide Atrazine in Water, Foods, and Human Urine Samples

Atrazine is a commonly used water-soluble agricultural herbicide in the United States. In this study, we measured the atrazine levels in water, beverages, foods, and urine samples obtained from young students at an urban university. The effects of physiological and behavioral factors were examined. Our results show that water samples obtained from Lake Erie and tap water both contained very low level of atrazine. Beverages and foods had various levels of atrazine contamination. Atrazine was also detected in the urine samples and mid-term physical activity appeared to be a factor to reduce the atrazine level in these subjects.

Distribution of atrazine and its phytoremediation by submerged macrophytes in lake sediments

We investigated sediments with high atrazine accumulation capability from 6 eutrophic lakes in Hubei Province of central China. Almost all lakes have atrazine in their sediments because of human activities. Honghu Lake and Liangzihu Lake were found to have higher levels of atrazine in sediment: 0.171 and 0.114 mg kg−1, respectively. The results showed that lake sediments could adsorb atrazine six times faster than soils. The equilibrium partition coefficient of atrazine desorption (KPd) is much larger than the adsorption equilibrium partition coefficient (KPa) of atrazine, indicating that the residue of atrazine in water is easily immobilized by the sediments. Meanwhile, the incubation experiment showed that the removal rateof atrazine in Potamogeton crispus-planted and Myriophyllum spicatum-planted sediments reached >90%, while the rate in unplanted sediments was 77.2 ± 2.12% over 45 d. In unplanted sediment, the half-life of atrazine dissipation was 14.30 d, which was strongly enhanced by P. crispus and M. spicatum, greatly reducing the half-life to 8.60 and 9.72 d, respectively. These two submerged macrophytes are considered to be potential tools in the remediation of atrazine-contaminated sediments.

Visible light photocatalytic degradation of herbicide (Atrazine) using surface plasmon resonance induced in mesoporous Ag-WO3/SBA-15 composite

Atrazine is one of the most extensively used herbicides. Being non-biodegradable in nature, it has a long half-life in water and hence it is prone to contaminate the water bodies and even seeps into the ground to pollute underground water. In this study, we developed a photocatalytic method for the degradation of Atrazine in water samples. Highly ordered mesoporous Ag-WO3/SBA-15 composites were tested as photocatalysts for the degradation of atrazine in water. It was found that 40% WO3 loading rendered an optimum surface area and material content in the SBA-15 template and hence favored the enhanced photocatalytic degradation of atrazine in water. The further addition of Ag onto the WO3/SBA-15 composite not only made this catalyst very effective in the most sought visible region due to solar energy harvesting, but also significantly reduced the electron hole recombination as evidenced by photoluminescence studies to enhance the degradation efficiency. As a result, the Ag-WO3/SBA-15 composite the photo-catalytic degradation of atrazine in water under visible radiation was significantly enhanced.

Degradation of atrazine in aqueous solution with electrophotocatalytic process using TiO2−x photoanode

The present study investigates the efficiency of a sustainable treatment technology, the electrophotocatalytic (EPC) process using innovative photoanode TiO2−x prepared by a magnetron sputter deposition process to remove the herbicide atrazine (ATZ) from water. The coexistence of anatase and rutile were identified by X-ray diffraction (XRD) and the presence of oxygen vacancies reduce the value of the observed bandgap to 3.0 eV compared to the typical 3.2 eV TiO2, this reduction is concomitant with a partial phase transition which is probably responsible for the increase in photoactivity. The experimental results with an initial concentration of ATZ (100 μg L−1) show that more than 99% of ATZ oxidation was obtained after 30 min of treatment and reaction kinetic constant was about 0.146 min−1. This good efficiency indicates that EPC process is an efficient, simple and green technique for degradation of pesticides such as ATZ in water. The analysis with liquid chromatography technique permits to identify, quantify and see the evolution of ATZ by-products which are generated by dechlorination, dealkylation and alkylic-oxidation mechanisms. Finally, the possible pathways of ATZ degradation by hydroxyl radicals were proposed.

MCR-ALS APPLIED TO THE QUANTITATIVE MONITORING OF THE ELECTRODEGRADATION PROCESS OF ATRAZINE USING UV SPECTRA: COMPARATIVE RESULTS WITH HPLC-DAD AS A REFERENCE METHOD

Electrodegradation of atrazine in water was performed using homemade (PA and PB) and purchased (PC) boron-doped diamond anodes. The degradation was monitored off-line by analyzing total organic carbon and high performance liquid chromatography with diode array detector (HPLC-DAD) and at-line by UV spectroscopy. The spectra were recorded every 2 min. The rank deficiency problem was resolved by assembling an augmented column-wise matrix. HPLC was employed to separate the original and byproducts degradation components. Aiming the same goal, multivariate curve resolution - alternating least squares (MCR-ALS) was applied to resolve the UV spectroscopic data. Comparison between HPLC and MCR-ALS separations is presented. By using MCR-ALS the spectra of atrazine and two byproducts were successfully resolved and the resulted concentration profiles properly represented the system studied. The ALS explained variance (R2) for PA, PB and PC was equal to 99.99% for all of them and the lack of fit for PA, PB and PC were 0.39, 0.34 and 0.54 respectively. The correlation (R) between the recovered and pure spectra were calculate for each electrodegradation, validating the MCR-ALS results. The average R was equal to 0.997. The spectral and concentration profiles described with this new approach are in agreement with HPLC-DAD results. The proposed method is an alternative to classical analyses for monitoring of the degradation process, mainly due to the simplicity, fast results and economy.

The effect of Funnelliformis mosseae inoculation on the phytoremediation of atrazine by the aquatic plant Canna indica L. var. flava Roxb.

Funnelliformis mosseaeinoculation exhibited a beneficial effect on the phytoremediation of atrazine in water by the aquatic plantCanna indicaL.

Removal of atrazine in water by combination of activated carbon and dielectric barrier discharge

Efficiency of modern wastewater treatment plants to remove or decompose persistent contaminants in low concentration is often insufficient to meet the demands imposed by governmental laws. Novel, efficient and cheap methods are required to address this global issue. We developed a new type of plasma reactor, in which atrazine decomposition by atmospheric dielectric barrier discharge (DBD) in dry air is combined with micropollutant adsorption on activated carbon textile and with extra bubbling of generated ozone. Investigation of reaction kinetics and by-product analysis shows that increasing input power with a factor 3.5 leads to deeper atrazine oxidation without significantly changing energy yield of atrazine removal. By-products of first and later generations are detected with HPLC–MS analysis in water and adsorbed on the activated carbon textile. Our reactor is compared in energy efficiency with reactors described in literature, showing that combination of plasma discharge with pollutant adsorption and ozone recycling is attractive for future applications of water treatment.

Cloud-point extraction preconcentration of sym-triazine herbicides to determination by gas chromatography

The cloud-point extraction of a number of sym-triazine herbicides by phases of nonionic Triton X-114 surfactant is studied. Based on the data obtained, conditions were found for the gas-chromatographic determination of prometryn, propazine, semoran, and atrazine in waters and foods with cloud-point extraction preconcentration.