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A new thiosemicarbazide-modified, sulfonamide-based poly (styrene) adsorbent (T-CSPS) was prepared starting from the reaction of chlorosulfonated polystyrene and thiosemicarbazide. It was characterized by SEM–EDX, FT-IR, and zeta potential. The T-CSPS was used as an adsorbent for the first time for the dispersive solid-phase microextraction (d-SPµE) and preconcentration of Pb(II) ions from waters and dill and lettuce extracts in the unified bioaccessibility method (UBM) saliva. Lead was then determined using the FAAS. In the first step of optimization, the solution pH was changed from 2 to 8, and pH 4 with a recovery value of 103% ± 5 was selected. Two milliliters of 2 mol L−1 HCl was chosen as eluent. Contact times were found to be only 2 min. Effects of coexisting ions and sample volume were tested. Under optimal conditions, the preconcentration factor (PF) and the adsorption capacity were 15 and 40 mg g−1. The RSD% was 2.2% and 3.1% for intra-day and inter-day precision, respectively. The LOD and LOQ were found to be 5.1 µg L−1 and 16.9 µg L−1, respectively. The accuracy of the d-SPµE was checked by TMDA-70.2 Lake water and BCR-482 Lichen-certified reference materials and also applying d-SPµE to spiked waters and lettuce and dill extracts in UBM saliva. [ABSTRACT FROM AUTHOR]

The wettability of black silicon (BSi) layers fabricated by reactive ion etching (RIE), metal‐assisted chemical etching (MACE), and laser‐induced etching (LIE) techniques is studied. The contact angles of wetting on the samples with deionized water and methylammonium iodide‐based perovskite solutions are determined. It is found that the element composition and the enlargement area factor of BSi layers have a significant effect on their wettability. When tested with water, the RIE and MACE BSi layers exhibit hydrophobic properties, while the LIE BSi layer demonstrates hydrophilic properties due to the SiOx‐rich surface structures. It is also shown that aging leads to a decrease in the water contact angle. Upon exposure to perovskite solution droplets, BSi layers become highly lyophilic. Based on the Wenzel and Cassie–Baxter models, the mechanisms responsible for the wetting states of the fabricated samples are identified. In the results obtained, valuable insights are provided into the potential of using these layers in tandem perovskite/silicon solar cells. [ABSTRACT FROM AUTHOR]

The principle of sovereignty, ie of supreme authority within a territory, is a pivotal principle of modern international law. Although the role of modern international law in establishing the sovereignty of states has changed many times, it must still be affirmed that international law sources are an important international legal basis for states to determine their sovereignty, including national sovereignty over the seas. The South China Sea (‘SCS') (Bien Dong or, East Sea in Vietnamese) has long been regarded as a major source of tension and instability in Pacific Asia. The purpose of this article is to discuss the views and positions of Vietnam on sovereignty over the two islands of Paracels (Hoang Sa in Vietnamese/Xisha in Chinese), Spratlys (Truong Sa in Vietnamese/Nansha in Chinese) and maritime zones in the South China Sea on the basis of international law and practice. [ABSTRACT FROM AUTHOR]

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In this article, microbiological studies of waters from Municipalities in the Burgas region are considered. Microbiological analyses were made on 112 borehole water samples. In 56% of the analyses carried out, it can be seen that there is no bacterial contamination in the examined drilling waters, in 44% of the examined samples bacterial growth is observed, of which 21% have the presence of E. coli and coliforms, and 23% with the presence of intestinal enterococci. The present study examines the importance and impact of water safety on human health. [ABSTRACT FROM AUTHOR]

Background: Per- and polyfluoroalkyl substances (PFAS) are considered 'contaminants of emerging concern' due to their environmental persistence, bio-accumulative potential, and adverse effects on human health. They are widely employed in producing various goods used in daily life, such as non-stick cookware, cleaning agents, and many industrial applications in aerospace, automotive, construction, electronics, and military, all of which ultimately end up in different environmental matrices. India's rapid economic growth necessitates a comprehensive understanding of its PFAS contamination levels and potential human and ecological exposure. Results: The present study reports the quantification of one long-chain and two short-chain perfluoroalkyl acids and three long-chain and two short-chain perfluorosulfonic acids and qualitative analysis using suspect screening in the waters of Chennai, Tamil Nadu, India. Samples were collected from surface and groundwater sources, including the Adyar river, Buckingham canal, Chembarambakkam lake, and the water treatment plant. The concentrations analyzed in all the samples ranged from 0.10 ng/L to 136.27 ng/L. Groundwater had some of the highest concentrations of PFAS. L-PFBS (up to 136.27 ng/L) and PFOA (up to 77.61 ng/L) are present in all the samples. The concentrations of all the target PFAS increased in the 5 to 103% range in the final treated water compared to the raw water of the water treatment plant. This treated water is distributed as a source of drinking water for the residents of Chennai. Additionally, the dominance of short-chain compounds (4–7 carbons) over long-chain compounds (> 7 carbons) was observed. Suspect screening revealed numerous precursors and other fluorinated compounds abundantly present in the samples. Conclusions: Our study revealed PFAS levels up to 136.27 ng/L in both surface and groundwater samples from Chennai. These findings raise concerns about potential risks to ecosystems and human well-being. The dominance of short-chain PFAS coupled with abundant precursors and unidentified fluorinated compounds indicates an ongoing shift toward alternatives. Conventional water treatment is ineffective in eliminating these chemicals from the water system; rather, increasing the PFAS concentrations from raw water to treated water necessitates advanced polishing steps. Industrial emissions, untreated domestic wastewater discharge, and open dump sites have been suspected as the significant sources of contamination, highlighting the need for further investigation to fully assess the extent of PFAS contamination in Chennai. Highlights: Groundwater and surface waters showed predominant presence of PFOA and L-PFBS. Concentrations of target PFAS increased from raw water to treated water in a conventional WTP. Numerous precursors and other fluorinated compounds are abundantly present in the collected samples. Open dump sites, untreated domestic wastewater discharge, and industrial emissions have been suspected as the contributing sources. [ABSTRACT FROM AUTHOR]

This research aims to study the source, spatial distribution characteristics and ecological risks of diuron in the coastal waters of the Yangtze River Estuary and Shanghai, water samples from 24 stations in the coastal waters of the Yangtze River Estuary, Hengsha Island （inland） waters and the waters near the Yangtze River Estuary Chinese sturgeon reserve were collected from October to November 2021, and the content of diuron in the surface water samples of each station was analyzed by solid phase extraction and high performance liquid chromatography tandem mass spectrometry. According to the test results, the mass concentration of diuron was detected in the water samples of 24 stations in three different regions. Among them, the detection range of diuron mass concentration at 10 stations along the Yangtze River Estuary in Shanghai was 182.43-439.38 ng/L, and the detection rate was 100%. The detection range of diuron mass concentration at 9 stations in Hengsha Island （inland） water area is 83.48-369.25 ng/L, and the detection rate is 100%. The detection range of diuron mass concentration at 5 stations near the Chinese sturgeon reserve is 1.97-2.85 ng/L, and the detection rate is 100%. The spatial distribution of diuron is mainly affected by factors like water transport, ship maintenance, agricultural activities, tides and seawater dynamics. Besides, the ecological risk assessment shows that the coastal waters along the Yangtze River Estuary in Shanghai are potentially at medium risk. Farming areas in Hengsha inland waters are at medium risk, and the nearby waters of the Nature Reserve are at low risk. The results show that the environment in the coastal waters of the Yangtze River Estuary in Shanghai is being threatened by the diuron, especially in the major ports and docks along the Yangtze River Estuary in Shanghai as well as the agricultural areas and river intersections in the Hengsha Island area. Although it will not threaten the Chinese sturgeon reserve in the short run, it still deserves attention. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate (PET) plastics find widespread use in various aspects of our daily lives but often end up in the environment as (micro)plastic waste. In this study, the adsorption efficiency of PET microplastics for U-232 has been investigated prior and after surface alteration (e.g. oxidation (PET-ox), MnO 2 -coating (PET/MnO 2) and biofilm-formation (PET/Biofilm)) in the laboratory (at pH 4, 7 and 9) and seawater samples under ambient conditions and as a function of temperature. The results revealed a significant increase in the adsorption efficiency upon surface alteration, particularly after biofilm development on the MP's surface. Specifically, the K d values evaluated for the adsorption of U-232 by PET, PET-ox, PET/MnO 2 and PET/Biofilm are 12, 27, 73 and 363, respectively, at pH 7 and under ambient conditions. The significantly higher adsorption efficiency of the altered and particularly biofilm-coated PET, emphasizes the significance of surface alteration, which may occur under environmental conditions. In addition, according to the thermodynamic investigations the adsorption of U-232 by PET-MPs (both non-treated and modified), the adsorption is an endothermic and entropy-driven reaction. A similar behavior has been also observed using seawater solutions and assumes that surface alteration is expected to enhance the radionuclide, stability, mobility and bioavailability in environmental water systems. [Display omitted] • Radionuclide (U-232) adsorption by surface-altered PET. • Surface-modification included: oxidation, MnO2-coating and Biofilm formation. • Enhanced adsorption efficiency by the surface-altered PET. • Supreme adsorption efficiency by the biofilm-coated PET. • Radionuclide adsorption by PET is an endothermic and entropy-driven process. [ABSTRACT FROM AUTHOR]

Plastic products have gained global popularity due to their lightweight, excellent ductility, high durability, and portability. However, out of the 8.3 billion tons of plastic waste generated by human activities, 80% of plastic waste is discarded due to improper disposal, and then transformed into microplastic pollution under the combined influence of environmental factors and microorganisms. In this comprehensive study, we present a thorough review of recent advancements in research on the source, distribution, and effect of microplastics. More importantly, we conducted deep research on the catalytic degradation technologies of microplastics in water, including advanced oxidation and photocatalytic technologies, and elaborated on the mechanisms of microplastics degradation in water. Besides, various strategies for mitigating microplastic pollution in aquatic ecosystems are discussed, ranging from policy interventions, the initiative for plastic recycling, the development of efficient catalytic materials, and the integration of multiple technological approaches. This review serves as a valuable resource for addressing the challenge of removing microplastic contaminants from water bodies, offering insights into effective and sustainable solutions. Environmental problems caused by plastic pollution in water bodies are among the most pressing issues of our time. This review introduces and discusses the source, distribution, and ecological impact of microplastics. Finally, the study on degradation of microplastic by advanced oxidation processes are discussed. [Display omitted] • The source, distribution, and impact of MPs has been discussed. • Research on MPs removal based on AOPs has been summarized and discussed. • Multiple treatment processes should be combined to removal MPs in water. • Perspectives in the MPs pollution control in water were pointed out. [ABSTRACT FROM AUTHOR]

This study presents the mineralogy and strontium isotope ratio (87Sr/86Sr) of 21 pathological biominerals (bladder and kidney stones) collected from patients admitted between 2018 and 2020 at the Department of Urology of the San Pio Hospital (Benevento, southern Italy). Urinary stones belong to the calcium oxalate, purine or calcium phosphate mineralogy types. Their corresponding 87Sr/86Sr range from 0.707607 for an uricite sample to 0.709970 for a weddellite one, and seem to be partly discriminated based on the mineralogy. The comparison with the isotope characteristics of 38 representative Italian bottled and tap drinking waters show a general overlap in 87Sr/86Sr with the biominerals. However, on a smaller geographic area (Campania Region), we observe small 87Sr/86Sr differences between the biominerals and local waters. This may be explained by external Sr inputs for example from agriculture practices, inhaled aerosols (i.e., particulate matter), animal manure and sewage, non-regional foods. Nevertheless, biominerals of patients that stated to drink and eat local water/wines and foods every day exhibited a narrower 87Sr/86Sr range roughly matching the typical isotope ratios of local geological materials and waters, as well as those of archaeological biominerals from the same area. Finally, we conclude that the strontium isotope signature of urinary stones may reflect that of the environmental matrices surrounding patients, but future investigations are recommended to ultimately establish the potential for pathological biominerals as reliable biomonitoring proxies, taking into the account the contribution of the external sources of Sr. [Display omitted] • 87Sr/86Sr ratios of Italian drinking waters and uroliths have been determined. • A general overlap between examined biominerals and drinking waters can be observed. • Slight discrepancies can be explained by additional external Sr inputs. • Patients stating to drink and eat local products delimited narrower 87Sr/86Sr range. • Uroliths could be promising proxies for a reliable biomonitoring purpose. [ABSTRACT FROM AUTHOR]