Three-dimensional (3D) batch ECC of raw health care facility wastewater (HCFWW) was adopted using stainless steel (SS) and aluminum (Al) scrap metal particle electrodes. ECC treatment was focused on priority quality parameters viz., chemical oxygen demand (COD), color, and other important water quality parameters. Sludge settling and filterability for post-ECC slurry were investigated after ECC. COD removals of 87.56 and 87.2% were achieved for current densities (CD) 83.33 and 125 A/m² using SS-3D electrodes, and similarly, 86.99 and 86.23% COD removal for Al-3D electrodes. Simultaneously, color removals were 88.50 and 87.60% for CD 166.66 A/m² (4A) using SS and Al-3D electrodes. Water quality parameters viz., nitrate, phosphates, and sulfate were also removed by 93.18%, 96.83%, and 41.07% for SS-3D electrodes, while Al-3D electrodes showed 93.15%, 96.72%, and 25.94% removal. Post-ECC slurry settling was good for all the applied CD using SS-3D electrodes generating dense and sturdy flocs. Al-3D electrodes showed excellent floc settling properties. SS-3D electrode flocs displayed good filterability at 1A with α: 2.497 × 10¹¹ m kg⁻¹ and Rₘ 1.946 × 10¹⁰ m⁻¹. Post-ECC slurry using Al-3D electrodes were viscous causing delayed filterability giving α: 1.1760 × 10¹¹ m kg⁻¹ and Rₘ 1.504 × 10⁹ m⁻¹ for 3A. E. coli was destroyed by 97 and 98% for 2A and 3A respectively. Clear water reclamation of 85–90% and pollutants/contaminants removed within a short HRT of 75 min proved the effectiveness of adopting 3D-ECC for treating raw HCFWW.

Iron oxide, in the form of magnetite (MG)–functionalized porous wollastonite (WL), was used as an adsorbent for heavy metal ions (cadmium and nickel) and oxyanions (chromate and phosphate) removal from water. The porous WL was synthesized from calcium carbonate and siloxane by controlled sintering process using low molecular weight submicrosized poly(methyl methacrylate) as a pore-forming agent. The precipitation of MG nanoparticles was carried out directly by a polyol-medium solvothermal method or via branched amino/carboxylic acid cross-linker by solvent/nonsolvent method producing WL/MG and WL-γ-APS/MG adsorbents, respectively. The structure/properties of MG functionalized WL was confirmed by applying FTIR, Raman, XRD, Mössbauer, and SEM analysis. Higher adsorption capacities of 73.126, 66.144, 64.168, and 63.456 mg g⁻¹ for WL-γ-APS/MG in relation to WL/MG of 55.450, 52.019, 48.132, and 47.382 mg g⁻¹ for Cd²⁺, Ni²⁺, phosphate, and chromate, respectively, were obtained using nonlinear Langmuir model fitting. Adsorption phenomena were analyzed using monolayer statistical physics model for single adsorption with one energy. Kinetic study showed exceptionally higher pseudo-second-order rate constants for WL-γ-APS/MG, e.g., 1.17–13.4 times, with respect to WL/MG indicating importance of both WL surface modification and controllable precipitation of MG on WL-γ-APS.

Polychlorinated biphenyls (PCBs) in breast milk has been determined. Therefore, it was necessary to develop and adapt an analytical method to analyze PCB compounds. The whole procedure was applied to 31 breast milk samples, which were collected from Polish mothers. The QuEChERS method was optimized as a fast and cheap sample preparation method. The procedure allowed us to obtain recovery values between 96.46% and 119.98% with acceptable relative standard deviations (3.36–12.71%). Gas chromatography with mass spectrometry (GC-MS) was used for final determination. The method was validated using parameters such as linearity, limit of detection and quantification, intra-day precision, and reproducibility. The mean concentration of ∑iPCBs in this study was 30.94 ng/g of lipid. Assigned daily intake of PCBs was lower than the tolerable daily intake, which shows that the analyzed milk is safe to the infants. However, the monitoring of PCBs in milk is still important, and the QuEChERS method with GC-MS can be an effective tool for tracking organic impurities in breast milk.

The impacts of biofouling on the retention of pharmaceutically active compounds (PhACs) by a commercially available nanofiltration membrane (NF 270) were systematically studied. Biofouling was achieved through inoculating live and dead Pseudomonas aeruginosa into artificial wastewater. In comparison to a clean membrane, an increase in PhAC rejection during biofouling with live cells was observed. However, the rejection behaviors presented more complex changes during biofouling with dead cells: PhAC rejection was below the clean membrane in the early biofouling stage; however, in the later stage, PhAC rejection was above the clean membrane. In addition, PhAC rejection behaviors present the similar tendency as salt rejection under both biofouling conditions. In addition, solute rejections were much lower for biofouling with dead cells than those for biofouling with live cells. Combined with biofilm characterization under both biofouling conditions, we could conclude that biofilm enhanced osmotic pressure (BEOP) due to higher cell counts and biofilm thickness led to a decrease in PhAC retention, especially for the dead cells. In addition, more dominant steric exclusion in the later stage of biofouling due to higher extracellular polymeric substances (EPS) concentration on the membrane surface resulted in an increase in PhAC retention.

An appraisal of seawater intrusion into the coastal aquifers is one of the major issues for groundwater resource management. The GALDIT model applies to the analysis of multiple parameters using systematic GIS techniques for mapping and assessment of seawater intrusion vulnerability. It demarcates the mapping of potential vulnerability that shows a higher vulnerability to seawater intrusion in various parts of the coast and the estimated vulnerability index value of 7.50 and 9.64. An area of 33.0 km² spread in the low-lying coastal area comprising estuaries, salt marshes, and saltpans shows the high vulnerability condition with an estimated vulnerability value of 6.42–7.50. An area of 73.20 km² spread over coastal and alluvial plains experiences moderate vulnerability (temporal salinity in the groundwater sources) with an estimated vulnerability index value of 5.46–6.42. Aquifers underlying coastal uplands (hard rock formations) and some parts of accretionary beaches (2.05 km²) are relatively protected fresh groundwater sources, wherein the estimated vulnerability index is 4.55–5.46. The vulnerability mapping of the GALDIT model using hydrochemical analysis of primary groundwater parameters such as TDS, Cl⁻, HCO₃, and Cl⁻/HCO₃ ratio is validated. Higher concentration of TDS (2637–4162 mg/l) and Cl⁻ (1268–2347 mg/l) is taken for the areas falling under higher vulnerability to seawater intrusion, especially in the placer mining sites and coastal areas facing erosion. Similarly, the groundwater sources of the low-lying areas including estuaries, salt marshes, saltpans, and backwater were noted to have higher values of Cl⁻/HCO₃ with a rationality of 9.87–12.18. Hydrological facies shows the highest concentration of NaCl in the groundwater sources within the proximity of eroded beaches, saltwater bodies, and sand mining areas. A hydrochemical facies evolution (HFE) diagram represents the hydrochemical facies of groundwater elements that shows an intrusion of seawater into the coastal aquifers underlying the very high vulnerable zones. Higher bicarbonate concentration (233–318 mg/l) is noticed in the upland areas and some parts of dunes and accreted beaches, sandy coasts, and uplands. Vulnerability analysis reveals that those areas near saltwater bodies and eroding coasts are prone to lateral and vertical diffusion of saltwater. The geodatabase developed through such modeling studies can help in planning and developing activities for sustainable groundwater resource management in coastal areas.

Phytophthora nicotianae is currently considered one of the most devastating oomycete plant pathogens, and its control frequently relies solely on the use of systemic fungicides. There is an urgent need to find environment-friendly control techniques. This study examined the chemical composition, inhibitory activity, and possible modes of action of the essential oil of Chrysanthemum indicum L. (EOC) flower heads against P. nicotianae. The EOC was obtained using hydrodistillation at a 0.15% yielded. It inhibited mycelial growth and spore germination of P. nicotianae at a minimum inhibitory concentration (MIC) of 200 μL/L, and exhibited fumigation effects (92.68% inhibition at 157.48 μL/L). Marked deformation of P. nicotianae mycelia included deformed tip enlargement, shrinkage, and rupture. Further, 55 and 47 compounds were identified using gas chromatography-mass spectrometry (GC-MS) and headspace solid-phase microextraction (HS-SPME) GC-MS analyses, representing 88.2% and 98.91% of the total EOC, respectively. Monoterpenes (25.77%) and sesquiterpenes (54.14%) were the major components identified using GC-MS, whereas monoterpenes were the main constituents in the HS-SPME GC-MS analysis. The higher proportions of sesquiterpenes and monoterpenes could be responsible for the inhibitory activity of EOC, which increased mycelia membrane permeability and the content of mycelial malondialdehyde (MDA) in a dose-dependent manner. Cell death also occurred. Thus, destruction of the cell wall and membrane might be two modes of action of EOC. Our results would be useful for the development of a new plant source of fungicide for P. nicotianae-induced disease.

Dissolved organic matter (DOM) is a critical component in aquatic ecosystems, yet its seasonal variability and reactivity remain not well constrained. These were investigated at the land-ocean interface of a subtropical river (Minjiang River, SE China), using absorption and fluorescence spectroscopy. The annual export flux of dissolved organic carbon (DOC) from the Minjiang River (5.48 × 10¹⁰ g year⁻¹) was highest among the rivers adjacent to the Taiwan Strait, with 72% occurring in spring and summer. The freshwater absorption coefficient a₂₈₀, DOC-specific UV absorbance SUVA₂₅₄ and humification index HIX were higher, while the spectral slope S₂₇₅–₂₉₅ and biological index BIX were lower in summer than in winter. This suggests intensified export of terrestrial aromatic and high molecular weight constituents in the rainy summer season. Six fluorescent components were identified from 428 samples, including humic-like C1–C3, tryptophan-like C4 and C6, and tyrosine-like C5. The freshwater levels of four components (C1, C2, C4, and C6) were lower while that of C5 was higher in the wet season than in the dry season, suggesting contrasting seasonal variations of different constituents. Laboratory experiments were performed to assess the effects of photochemical and microbial degradation on DOM. Photo-degradation removed chromophoric and fluorescent DOM (CDOM and FDOM) effectively, which was stronger (i) for high molecular weight/humic constituents and (ii) during summer under higher solar radiation. Microbial degradation under laboratory controlled conditions generally showed little effect on DOC, and had smaller impact on CDOM and FDOM in winter than in summer. Overall, this study showed notable seasonal changes in the chemical composition and reactivity of DOM at the land-ocean interface, and demonstrated the significant effects of photo-degradation.

Metal–organic frameworks (MOFs) are attractive novel classes of porous materials with diverse potentiality and easily tailored structures. It is desirable to evaluate the performance of MOFs as photocatalysts for organic contaminant removal in aqueous matrixes. In this study, iron-based MIL-101(Fe) was synthesized and a photo-Fenton reaction system (multiple wavelength light + MIL-101(Fe) + H₂O₂) was developed for elimination of tris(2-chloroethyl) phosphate (TCEP). Degradation pattern of TCEP followed an S-shape curve, which included a slow induction period and a rapid radical oxidation process. Transport of reactants into MIL-101(Fe) and the activation of electron transport within Fe–O clusters of MIL-101(Fe) may be the dominant mechanisms in the induction period, while a pseudo-first-order kinetics was observed in the hydroxyl radical oxidation process. Removal efficiencies in these two stages highly depended on the reaction conditions. Irradiation at 420 nm and acid condition were conductive, while high temperature and high [H₂O₂]:[MIL-101(Fe)] mass ratio accelerated the reaction. Before complete mineralization, eleven degradation products were generated, and the dominant degradation pathways included cleavage, hydroxylation, carbonylation, and carboxylation. Under acid condition (pH = 3), only 1% mass loss was observed after 60-min reaction, but the iron leakage was aggravated when pH increased. Furthermore, this MOF-photo-Fenton system demonstrated a robust performance on TCEP degradation in actual wastewater matrixes under acid condition. Generally, the MOF-photo-Fenton system is a potential technology for elimination of organic pollutants in aqueous solution.

Arsenic (As) is often found naturally as the co-contaminant in the uranium (U)-contaminated area, obstructing the bioremediation process. Although the U-contaminated environment harbors microorganisms capable of interacting with U which could be exploited in bioremediation. However, they might be unable to perform with their full potential due to As toxicity. Therefore, potential in arsenic resistance and oxidation is greatly desired among the microorganisms for a continued bioremediation process. In this study, arsenic-resistant bacteria were isolated from U ore collected from Bundugurang U mine, characterized and their As oxidation and U removal potentials were determined. 16S rRNA gene sequencing and phylogenetic analysis showed the affiliation of isolated bacteria with Microbacterium, Micrococcus, Shinella, and Bacillus. Except Bacillus sp. EIKU7, Microbacterium sp. EIKU5, Shinella sp. EIKU6, and Micrococcus sp. EIKU8 were found to resist more than 400 mM As(V); however, all the isolates could survive in 8 mM As(III). The isolates were found to readily oxidize As under different culture conditions and are also resistant towards Cd, Cr, Co, Ni, and Zn. All the isolates could remove more than 350 mg U/g dry cells within 48 h which were found to be highly dependent upon the concentration of U, biomass added initially, and on the time of exposure. Ability of the isolates to grow in nitrogen-free medium indicated that they can flourish in the nutrition deprived environment. Therefore, the recovery of isolates with the potent ability to resist and oxidize As from U ore might play an important role in toxic metal bioremediation including U.

In this paper, a crosslinked carboxymethyl starch (CCMS) was prepared with corn starch as the raw material, epichlorohydrin as the crosslinking agent, and chloroacetic acid as the etherifying agent through a series of crosslinking, alkalization, and etherification reactions, respectively. Nano-TiO₂ was loaded onto the surface of the CCMS by the sol-gel method to obtain a TiO₂/CCMS composite. The TiO₂/CCMS composite was characterized by XPS, XRD, SEM, and BET. XPS showed that the surface chemical composition of the TiO₂/CCMS composite material contained titanium; XRD diffraction patterns indicated that the crystal form of the TiO₂/CCMS composite was a combination of the CCMS and anatase TiO₂. The surface morphology obtained by SEM showed that there were nano-TiO₂ particles on the surface of the CCMS. The specific surface area of the TiO₂/CCMS composite was larger than that of CCMS. The adsorption-photodegradation performance of the TiO₂/CCMS composite was also studied under UV irradiation, and the results showed that significant adsorption-photodegradation synergies occurred.