{"title":"Efficient pretreatment method for analyzing microplastics in urban road dust containing composite materials.","authors":"Kanako Yamamoto, Soyoung Lee, Tomohiro Tobino, Fumiyuki Nakajima","doi":"10.1002/wer.70028","DOIUrl":"10.1002/wer.70028","url":null,"abstract":"<p><p>Tire wear particles (TWPs) and road marking paint (RMP) fragments are main sources of composite microplastics (MPs) in urban road dust and contribute significantly to the load of MPs in water environments. However, few studies have investigated the influence of organic decomposition such as cellulolytic enzyme decomposition (EZM) and Fenton (FT), on the abundance and characteristics of composite MPs in the environment. This study aimed to evaluate an organic matter decomposition method suitable for MP analysis using urban road dust containing composite materials, focusing on EZM and FT methods. The EZM has 1.1-4.5 times as high recovery of synthetic polymers as FT based on particle number. The difference in the number of orange particles was thought to be one of the factors behind this. Sodium citrate buffer used in EZM might degrade any components in the RMP-suspected orange particles and reduce the particle density to float in the NaI solution. For black tire-suspected particles, which were detected in large numbers, no significant difference was confirmed between EZM and FT in the number of these particles, but FT methods might affect the proportion of tire material in tire-suspected materials. The EZM method may be useful for quantification of composite MPs and is more suitable for analyzing samples in which there may be many RMP-suspected particles due to the characteristics of the surrounding environment or catchment area. PRACTITIONER POINTS: Tires and road marking paint (RMP) are main sources of composite microplastics (MPs) washed into stormwater from road dust. The cellulolytic enzyme decomposition is useful for analysis of composite MPs and comprehensive understanding of materials in the environment. It is necessary to select an organic matter decomposition method that suits the sample characteristics and research purpose.</p>","PeriodicalId":23621,"journal":{"name":"Water Environment Research","volume":"97 2","pages":"e70028"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11822084/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143411105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nese Yilmaz, Ilhan Dogan, Goksel Demir, Ibrahim Ertugrul Yalcin, Saifullah Khan, Ibrahim Ilker Ozyigit
{"title":"Assessment of pollution in Alibeykoy Dam Lake (Istanbul, Türkiye) and its influent streams: Phytoplankton composition and heavy metal accumulation.","authors":"Nese Yilmaz, Ilhan Dogan, Goksel Demir, Ibrahim Ertugrul Yalcin, Saifullah Khan, Ibrahim Ilker Ozyigit","doi":"10.1002/wer.70030","DOIUrl":"10.1002/wer.70030","url":null,"abstract":"<p><p>In this study, the pollution levels of Alibeykoy Dam Lake were assessed by examining phytoplankton distribution, physicochemical parameters, nutrient content, and heavy metal concentrations. Alibeykoy Dam is a critical drinking water source for the Istanbul metropolitan area. Water samples were collected from the lake and six influent streams (Cebeci, Pirincci, Sidan, Bolluca, Gulgen, and Kocaman) in January, February, May, and September of 2021. A total of 36 taxa from seven divisions were identified, including Bacillariophyta (14), Charophyta (2), Chlorophyta (9), Cryptophyta (1), Cyanobacteria (3), Euglenozoa (4), and Miozoa (3). Diatoms were found to be the dominant group in terms of species richness and abundance. The dominant species recorded in each site were as follows: Microcystis aeruginosa in Alibeykoy Dam and Sidan Creek, Cyclotella ocellata in Cebeci and Gulgen Creeks, Scenedesmus sp. in Pirincci Creek, Navicula cryptocephala in Bolluca Creek, and Sphaerocystis planctonica in Kocaman Creek. Mesotrophic and eutrophic phytoplankton species suggested that the lake is nearing eutrophic conditions. This conclusion was further supported by high concentrations of heavy metals and nutrients detected in the water samples. This research is significant because it provides a comprehensive understanding of the ecological status of Alibeykoy Dam Lake, a critical resource for drinking water in Istanbul. The study highlights potential risks associated with eutrophication and heavy metal accumulation by identifying pollution levels and dominant species. These findings are vital for implementing effective water resource management strategies, ensuring the lake's sustainability, and protecting public health. PRACTITIONER POINTS: The pollution rate of Alibeykoy Dam Lake was determined. The presence of mesotrophic and eutrophic species of phytoplankton indicated the lake's trophic structure. The measurements were done to estimate the lake's heavy metal and nutrient contents.</p>","PeriodicalId":23621,"journal":{"name":"Water Environment Research","volume":"97 2","pages":"e70030"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143190371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Meera Rajan, D Karunanidhi, B Gurugnanam, T Subramani
{"title":"Assessment of groundwater suitability for drinking and irrigation purposes with probable health threats in a semiarid river basin of South India.","authors":"Meera Rajan, D Karunanidhi, B Gurugnanam, T Subramani","doi":"10.1002/wer.70011","DOIUrl":"10.1002/wer.70011","url":null,"abstract":"<p><p>In the semiarid river basin of south India, the present study focuses on the appropriateness of water for drinking and irrigation as well as the risks to human health posed by pollutants. A total of 68 groundwater samples were evaluated for irrigation and consumption purposes. With a high electrical conductivity peaking at 3430 μS/cm and an alkaline composition, the groundwater has a high salinity and poor water quality. Durov's figure displays a trend along the dissolution or mixing line and identifies the geochemical facies of groundwater samples. According to water quality indexes, the majority of samples are categorized as unfit for human consumption (26.47%), extremely bad (36.76%), and poor (26.47%). According to elemental concentrations, the data are grouped into three clusters using hierarchical cluster analysis. According to the geographical distribution, nitrate levels are safe over about 320.25 km<sup>2</sup> and dangerous over about 121.10 km<sup>2</sup>, whereas fluoride levels are safe over about 293.92 km<sup>2</sup> and dangerous over about 147.43 km<sup>2</sup>. About 50.65 km<sup>2</sup>, 14.70% of the samples, fell into the no restriction category for irrigation, indicating acceptable standards. Low sodium levels in soils are indicated by parameters like SAR, %Na, PI, RSC, MR, and KR; SAR values fall into the C2S1, C3S1, and C4S1 categories. According to Doneen's diagram, 70.5% of samples had a PI >75, indicating suitability; the Wilcox diagram classified 22.05% of samples as excellent and 69.11% as good to permissible for irrigation. According to human health risk assessment, 75% of babies, 63% of children, 75% of teens, and 54% of adults have THI values >1 for fluoride. About 45% of newborns, 42% of kids, 45% of teenagers, and 29% of adults are at risk for nitrate. Infants, kids, and teenagers are at the danger. In order to safeguard human health against fluoride and nitrate, the study emphasizes the necessity of efficiently managing groundwater resources, lowering agricultural pollution, and assuring clean drinking water. PRACTITIONER POINTS: In the area, 79.25 km<sup>2</sup> has good drinking water quality based on DWQI. Based on IWQI, 70.33 km<sup>2</sup> area is recognized as suitable for agricultural practices. Geogenic and anthropogenic activities contribute to fluoride and nitrate pollution in water. Based on THI, infants and children are more prone to fluoride and nitrate contamination.</p>","PeriodicalId":23621,"journal":{"name":"Water Environment Research","volume":"97 2","pages":"e70011"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143190359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Quantifying and characterizing major DOC fractions in water treatment processes: A simplified SPE method without recovering sorbed compounds.","authors":"Saeideh Mirzaei, Beata Gorczyca","doi":"10.1002/wer.70047","DOIUrl":"10.1002/wer.70047","url":null,"abstract":"<p><p>Practitioners often use specific UV<sub>254</sub> absorption (SUVA) as an indicator of hydrophobic (HPO) dissolved organic carbon (DOC) to evaluate removal efficiency and estimate trihalomethane formation potential (THMFP). However, current fractionation methods, such as solid-phase extraction (SPE), primarily focus on recovering sorbed compounds, and assume that treatment impacts only the quantity, not the characteristics, of DOC fractions. Additionally, varying recovery rates and inconsistent fractionation pH definitions complicate cross-study comparisons of hydrophilic and HPO DOC composition. To address these issues, we tested three pH fractionation approaches (pH 3, pH 7, and sequential adjustment) and observed significant differences in DOC content, SUVA, and specific THMFP (STHMFP) between SPE filtrates at pH 3 and pH 7, which were most likely because of ionizable acidic DOC compounds becoming HPO at lower pH levels. Based on these findings, we developed a new fractionation method to estimate the quantity and characteristics of major DOC fractions-hydrophilic neutral (HPIN), total acidic (TA = HPOA + HPIA), and hydrophobic neutral (HPON)-without the need to recover sorbed fractions. Applying this method in a conventional coagulation/softening plant revealed HPON decreased while the relative amounts of HPI and TA increased after the treatment. However, the treated water HPI exhibited significantly higher STHMFP and contained approximately twice the proportion of low-molecular-weight compounds than raw water HPI, highlighting significant changes in both the content and properties of DOC fractions throughout the treatment process. Our study indicates that the contribution of HPI DOC fraction to SUVA and STHMFP in treated water is greater than that of HPO DOC. PRACTITIONER POINTS: A two-stage ENV to estimate major DOC fractions without recovering sorbed compounds. One ENV cartridge at pH 3 can effectively isolate HPI DOC, replacing sequential ENV. Coagulation and lime/soda softening altered characteristics of DOC fractions. HPI DOC in treated water contributes to SUVA and STHMFP more than HPO fraction.</p>","PeriodicalId":23621,"journal":{"name":"Water Environment Research","volume":"97 2","pages":"e70047"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11840460/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143459822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Microwave-enhanced Fe<sup>0</sup>/PDS system for treating refractory organic matter in biotreated landfill leachate effluent.","authors":"Feiyan Fang, Xi Luo, Qibin Li","doi":"10.1002/wer.70040","DOIUrl":"10.1002/wer.70040","url":null,"abstract":"<p><p>The effluent produced from treating landfill leachate via biological methods still contains a large amount of refractory organic matter and needs to be further treated. In this study, we used a microwave-enhanced zero-valent iron/peroxydisulfate (MW/Fe<sup>0</sup>/PDS) system for the further treatment of biotreated landfill leachate effluent (BTLE). We investigated the efficiency and mechanism of removing refractory organic matter from BTLE. The results show that under the conditions of MW = 240 W, [PDS]<sub>0</sub> = 40 mM, [Fe<sup>0</sup>]<sub>0</sub> = 10 mM, and t = 12 min, the MW/Fe<sup>0</sup>/PDS system best removed organic matter in the BTLE. The removal rates of UV absorbance at 254 nm, color number, and total organic carbon reached 76.94%, 93.50%, and 63.08%, respectively. The aromaticity, degree of humification, molecular weight, and degree of polymerization of the organic matter decreased significantly. The surface morphology and elemental valence analysis of Fe<sup>0</sup> before and after the reaction revealed that iron-based oxides (i.e., Fe<sub>2</sub>O<sub>3</sub>, Fe<sub>3</sub>O<sub>4</sub>, FeOOH, and Fe (OH)<sub>3</sub>) formed on the surface of Fe<sup>0</sup>. The refractory organic matter was removed by homogeneous and heterogeneous Fenton-like reactions and the adsorption-precipitation of iron-based colloids. The thermal and nonthermal effects of MW promoted direct PDS decomposition, accelerated the formation of Fe<sup>2+</sup> on the surface of Fe<sup>0</sup>, promoted the redox cycle of Fe<sup>3+</sup>/Fe<sup>2+</sup>, and generated more sulfate radicals (SO<sub>4</sub> <sup>•-</sup>). Together, these effects improved the removal efficiency of refractory organic matter. The results of this study can serve as a theoretical basis for the use of the MW/Fe<sup>0</sup>/PDS system to treat refractory organic matter in BTLE. PRACTITIONER POINTS: A microwave-enhanced Fe<sup>0</sup>/PDS system is effective for removing organic matter from landfill leachate. Colored and fluorescent organic matter in the landfill leachate was efficiently degraded. Heterogeneous and homogeneous effects Fenton reactions are involved in the system.</p>","PeriodicalId":23621,"journal":{"name":"Water Environment Research","volume":"97 2","pages":"e70040"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143433842","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The application of duckweed (Lemna minor) and freshwater mussels (Anodonta cygnea) as living biofilters integrating with a filtration system to maintain water quality in juvenile trout (Oncorhynchus mykiss) rearing using the small scale RAS system.","authors":"Muhammad Hanif Azhar, Devrim Memiş","doi":"10.1002/wer.70046","DOIUrl":"10.1002/wer.70046","url":null,"abstract":"<p><p>Increasing nutrient concentrations in fish culture systems over time can reduce water quality. However, the nutrient increase can be remediated by pairing organisms at lower trophic levels with a mechanical filtration system to improve nutrient removal efficiency and water quality for fish culture. This research uses the RAS system to determine the performance of integrating living organisms as biofilters in rearing juvenile rainbow trout (Oncorhynchus mykiss) for 56 days. Duckweed (Lemna minor) was added to replicate tanks at three treatment levels: T1 (100 g wet weight and 20% area coverage), T2 (200 g wet weight and 40% area coverage), and T3 (300g wet weight and 60% area coverage). The duckweed in each treatment tank was supplemented with 20 freshwater mussels (Anodonta cygnea) with an average body weight of 56 ± 1.0 g. Physical and chemical water quality parameters were measured in fish tanks and all ponds in the RAS system. Fish from the rearing tanks were weighed every two weeks. Duckweed biomass was measured weekly; the mussels were weighed at the beginning and end of the study, and the mussels were measured at the beginning and end of the rearing period. The fish was partially harvested every two weeks to maintain constant fish biomass. Using duckweed (L. minor) with different biomass weights and areal coverage, coupled with the freshwater mussels (A. cygnea) as living biofilters, had a significant effect (P < 0.05) on water quality parameters. Ammonium (NH<sub>4</sub>), nitrite (NO<sub>2</sub>), and nitrate (NO<sub>3</sub>) concentrations decreased throughout the study. During the study period, juvenile trout experienced growth with an SGR of 2.62-2.72%/gram with a survival rate of 100%. Partial harvesting during the rearing period positively impacted the average body weight of fish growth and duckweed biomass. The best duckweed growth performance was found in treatment T1 (cover area 20% with wet weight 100 g) with a productivity of 9.4 (g/m<sup>2</sup>/day). PRACTITIONER POINTS: Twenty percent duckweed coverage with freshwater mussels achieves optimal nutrient removal in RAS systems, improving water quality efficiently and growth better than other treatments. Combined biofilters (duckweed-mussel) and filtration units reduce operational costs while maintaining high fish survival rates in RAS systems. Integration of living biofilters provides sustainable water treatment without chemical additives, suitable for small-scale aquaculture operations.</p>","PeriodicalId":23621,"journal":{"name":"Water Environment Research","volume":"97 2","pages":"e70046"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143450332","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Charles R Hammond, Misael Sebastián Gradilla Hernández, Frank J Loge
{"title":"Microalgal-bacterial aggregates for wastewater treatment: Origins, challenges, and future directions.","authors":"Charles R Hammond, Misael Sebastián Gradilla Hernández, Frank J Loge","doi":"10.1002/wer.70018","DOIUrl":"10.1002/wer.70018","url":null,"abstract":"<p><p>Microalgal-bacterial aggregates are promising for wastewater treatment because they remove organic matter, nitrogen, and phosphorus while producing biomass that settles quickly. This review details the development of microalgal-bacterial aggregates, identifies key challenges, and proposes future research directions. While many studies have been performed in the laboratory with synthetic wastewater and artificial lighting, more research is needed to better understand how to form and sustain aggregates at larger scales with real wastewater and natural lighting. While it appears that microalgal-bacterial aggregates are unlikely to replace or augment conventional activated sludge, they have the potential to improve resource recovery in existing microalgae-based wastewater treatment processes (e.g., high-rate algal ponds). Alternatively, attached-growth bioreactors utilizing microalgal-bacterial consortia may be able to compete directly with conventional activated sludge while providing the benefits that microalgae offer, although additional research is needed. PRACTITIONER POINTS: More pilot and full-scale research on microalgal-bacterial processes is needed. Microalgae cultivation with short retention times is challenging. Attached-growth processes may allow for competitive footprint requirements.</p>","PeriodicalId":23621,"journal":{"name":"Water Environment Research","volume":"97 2","pages":"e70018"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11790518/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143123645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Ultraviolet-enhanced Fe<sup>0</sup>-activated H<sub>2</sub>O<sub>2</sub> process for the removal of refractory organic matter from landfill leachate: Performance and mechanism.","authors":"Guonan Zhao, Ke Feng","doi":"10.1002/wer.70022","DOIUrl":"10.1002/wer.70022","url":null,"abstract":"<p><p>The Fenton-like process, utilizing zero-valent iron (Fe<sup>0</sup>) and hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>), is employed to degrade refractory organic matter in membrane bioreactor (MBR) effluent derived from landfill leachate. However, the rate-limiting Fe<sup>2+</sup>/Fe<sup>3+</sup> redox step diminishes treatment efficacy and generates substantial iron sludge. This study elucidates the mechanism by which ultraviolet (UV) irradiation augments the Fe<sup>0</sup>/H<sub>2</sub>O<sub>2</sub> process for the removal of refractory organic matter in MBR effluent. The results show that the UV- enhanced H<sub>2</sub>O<sub>2</sub> process effectively disrupts the aromatic structure of organic compounds, reducing molecular weight, degree of polymerization, and humification. Compared with the Fe<sup>0</sup>/H<sub>2</sub>O<sub>2</sub> process, the removal efficiency of UV<sub>254</sub>, color number, and total organic carbon in the effluent treated by the UV/Fe<sup>0</sup>/H<sub>2</sub>O<sub>2</sub> process increased by 24.16%, 14.62%, and 57.46%, respectively. Concurrently, the generation of iron sludge was reduced by 21.6%. This enhancement is primarily attributed to UV's ability to intensify the Fe<sup>2+</sup>/Fe<sup>3+</sup> redox cycle and expedite the surface corrosion of Fe<sup>0</sup>, yielding more iron oxides. This accelerates the decomposition of H<sub>2</sub>O<sub>2</sub>, generating a higher quantity of <sup>•</sup>OH through both homogeneous and heterogeneous Fenton-like reactions. The refractory organic matter is removed through the oxidation by <sup>•</sup>OH, as well as the adsorption and precipitation facilitated by iron-based colloids. PRACTITIONER POINTS: UV promotes Fe<sup>0</sup>/H<sub>2</sub>O<sub>2</sub> process to degrade refractory organic matter in MBR effluent. UV promotes Fe<sup>0</sup> to dissolve more Fe<sup>2+</sup> and the redox cycle of Fe<sup>2+</sup> and Fe<sup>3+</sup>. The dosage of H<sub>2</sub>O<sub>2</sub> or Fe<sup>0</sup> influences the treatment effect of the process.</p>","PeriodicalId":23621,"journal":{"name":"Water Environment Research","volume":"97 2","pages":"e70022"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143123682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Microplastics occurrence in commercial crab Scylla serrata from Kaveri River of Tamil Nadu: An emerging concern for community health.","authors":"Arunagiri Ragu Prasath, Kandasamy Selvam, Chinnappan Sudhakar","doi":"10.1002/wer.70036","DOIUrl":"10.1002/wer.70036","url":null,"abstract":"<p><p>Microplastic (MPs) pollution has engulfed global aquatic systems, and the concerns about MPs translocation and bioaccumulation in fish, crabs, and other marine organisms are now an unpleasant truth. In the past few years, MPs pollution in freshwater systems, particularly rivers, and subsequently in freshwater organisms, especially in crabs, has caught the attention of researchers. Rivers provide livelihood to approximately 40% of the global population through food and potable water. Hence, assessment of emerging contaminants like MPs in waterways and the associated fauna is crucial. This study assessed MPs in crab S. serrata across the largest riverine system of south India, the Kaveri River. The MPs were characterized by optical microscopy, and field emission scanning electron microscopy-energy dispersive X-ray (FESEM-EDX) analysis for their number, shape, size, and color. Polymer composition was analyzed using attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR) and Raman spectroscopy. Polypropylene (PP), polystyrene (PS), polyamide (PA), and polyvinyl chloride (PVC) were the dominant plastic polymers in the crab intestine. Additionally, the FE-SEM analysis revealed that the MPs have differential surface morphology with rough surfaces, porous structures, fissures, and severe damage. Most MPs comprised Na, Si, Mg, Cl, K, and Ca, according to EDX analyses. The findings might provide insight into the status of MPs in S. serrata at Kavery river that could help in formulating regulations for MPs reduction and contamination in rivers eventually to protect the environment and human health. PRACTITIONER POINTS: The first findings on the identity and properties of MPs in crabs from the Kaveri River at Mettur Dam. A simple and cost-effective approach for extracting microplastics from crab samples from Mettur Dam, Kaveri River, Salem District, Tamil Nadu, India. Microplastics were detected using optical microscopy, ATR-FTIR, and FE-SEM.</p>","PeriodicalId":23621,"journal":{"name":"Water Environment Research","volume":"97 2","pages":"e70036"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143366100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wenquan Sun, Yan Wang, Xingwang Yang, Ziran Wang, Hanqing Zhu, Jun Zhou, Yongjun Sun
{"title":"Catalytic ozone oxidation of chemical RO membrane concentrate wastewater by a Cu-Ce@γ-Al<sub>2</sub>O<sub>3</sub> ozone catalyst.","authors":"Wenquan Sun, Yan Wang, Xingwang Yang, Ziran Wang, Hanqing Zhu, Jun Zhou, Yongjun Sun","doi":"10.1002/wer.70034","DOIUrl":"10.1002/wer.70034","url":null,"abstract":"<p><p>A Cu-Ce@γ-Al₂O₃ catalyst was developed for the efficient treatment of chemical reverse osmosis (RO) membrane concentrate wastewater. The working conditions and reaction mechanisms of Cu-Ce@γ-Al₂O₃ catalytic ozonation were systematically investigated, and its application in the catalytic ozonation of chemical RO membrane concentrate wastewater was explored. The catalyst was comprehensively characterized using scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) analysis, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), X-ray fluorescence (XRF), and Fourier-transform infrared (FTIR) spectroscopy, revealing its microstructure, elemental composition, and crystal structure. The optimal reaction conditions were identified as follows: ozone dosage of 8 mg/L/min, initial pH of 9.0, catalyst filling ratio of 10%, and a reactor height-to-diameter ratio of 5:1. Under these conditions, the catalytic ozonation achieved a chemical oxygen demand (COD) removal rate of 63.4%. Free-radical quenching experiments confirmed that hydroxyl radicals (·OH) played a dominant role in the catalytic ozonation system. Kinetic analysis revealed that the catalytic ozonation of chemical RO membrane concentrate wastewater with Cu-Ce@γ-Al₂O₃ followed second-order kinetics. The degradation mechanisms of organic matter in the wastewater were further analyzed using ultraviolet-visible (UV-Vis) spectroscopy and three-dimensional fluorescence spectroscopy. Additionally, a weighted rank sum ratio (WRSR) evaluation model was developed to provide a comprehensive assessment of the process performance. PRACTITIONER POINTS: Cu-Ce@γ-Al<sub>2</sub>O<sub>3</sub> catalysts with excellent catalytic performance were prepared. Efficient catalytic ozonation of chemical RO membrane concentrate with high salinity was realized. Degradation mechanism of organic pollutants by catalytic ozonation is clarified. Evaluation model for catalytic ozonation of chemical RO membrane concentrate was established.</p>","PeriodicalId":23621,"journal":{"name":"Water Environment Research","volume":"97 2","pages":"e70034"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143383334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}