Arsenic (As) contamination of soil and groundwater poses a huge threat to world health by polluting food systems and causing major health problems, such as cancer, cardiovascular disease,skin lesions,kidney damage and other serious health problems. In recent years, there has been a lot of effort into designing, synthesizing, and developing chemosensors for arsenic species. Chemosensors containing heteroatoms such as oxygen, nitrogen, and sulfur provide coordination sites for metal ion detection. This study investigates the study of organic compounds for the fluorimetric and colorimetric detection of As ions in biological, agricultural, and environmental samples. These chemosensors are based on the skeleton of Schiff bases, thiourea, and pyridine. By comparing their identification capabilities, we hope to guide the development of future arsenic chemosensors that are efficient, sensitive, and selective, leading to more accessible methods for arsenic monitoring in a variety of real-world applications.

Background: The detection of metal ions represents a critical analytical challenge due to their persistent environmental accumulation and severe toxic effects on ecosystems and human health. Even at trace concentrations, toxic metal ions can cause irreversible biological damage, necessitating the development of sensitive, selective, and rapid monitoring platforms. Advanced detection systems are urgently needed for environmental surveillance, industrial effluent control, and food/water safety applications where regulatory compliance and early warning capabilities are paramount. Results: This work presents an etching-based sensor array to identify and discriminate Pb2+, Hg2+, Cu2+, NO2-, Cr6+, and As3+ as hazardous ions. Au@Ag core@shell nanorods were utilized as sensing elements in different pH values in the presence of thiosulfate and thiourea as key elements in the oxidation of nanoparticles. Analytes' response patterns in the range of 1.0-30 mu M were analyzed via various methods, including heatmap, bar plot, and linear discriminant analysis (LDA), showing perfect discrimination. To ensure the sensor's applicability in real samples, we conducted meticulous testing on different sources, including tap water, well water, tilapia pond water, tomato soil extract, and urine samples. Significance: The sensor demonstrated excellent performance in classifying mixture samples and providing precise and accurate detection in real samples. This innovation offers a promising future for etching-based sensor arrays by utilizing core-shell nanoparticles as sensitive sensing elements and a significant contribution to global efforts in safeguarding public health and the environment from the threat of pollutants.

To address the growing and urgent need for quick and accurate food spoilage detection systems as well as to reduce food resource wastage, recent research has focused on intelligent bio-labels using pH indicators. Accordingly, we developed a dual-channel intelligent label with colorimetric and fluorescent capabilities using black lycium anthocyanin (BLA) and 9,10-bis(2,2-dipyridylvinyl) anthracene (DSA4P) as colorimetric and fluorescent indicators within a composite film consisting of chitosan (Cs), whey protein (Wp), and sodium tripolyphosphate (STPP). The addition of STPP as a cross-linking agent significantly improved the hydrophobicity, mechanical properties, and thermal stability of the Cs/Wp composite films under low pH conditions. After the incorporation of BLA and DSA4P, the resulting dual-channel intelligent label (Cs/Wp/STPP/BLA/DSA4P) exhibited superior hydrophobicity, as indicated by a water contact angle of 78.03(degrees). Additionally, it displayed enhanced mechanical properties, with a tensile strength (TS) of 3.04 MPa and an elongation at break (EAB) of 81.07 %, while maintaining a low transmittance of 28.48 % at 600 nm. After 25 days of burial in soil, the label was significantly degraded, which showcases its eco-friendly nature. Moreover, the label could visually detect color changes indicating volatile ammonia concentrations (25-25,000 ppm). The color of the label in daylight gradually shifted from brick-red to light-red, brownish-yellow, and finally light-green as the ammonia concentration increased. Correspondingly, its fluorescence transitioned from no fluorescence to green fluorescence with increasing ammonia concentration, gradually intensifying under 365-nm UV light. Furthermore, the label effectively monitored the freshness of shrimp stored at temperatures of 4 C-degrees, 25( degrees)C, and - 18(degrees) C. Thus, the label developed in this study exhibits significant potential for enhancing food safety monitoring.

Rivers play a vital role in our ecosystems, providing fresh water, supporting rich biodiversity, and contributing to human well-being. However, in the face of climate change and intensive human activities, the sediment load in rivers can reach critical levels, presenting a complex set of challenges that require immediate action. The increased sediment load can alter aquatic habitats, clog channels, reduce reservoir storage capacity, and increase the risk of flooding. These direct threats entail high costs in terms of material and ecological damage, loss of life, and expenditure on rebuilding damaged infrastructure. The quantification of bedload in watercourses is therefore crucial for maintaining water and soil resources, safeguarding riparian communities, and preserving ecological balance. The study reports the findings of a three-year monitoring of the bed load of Skhirate Wadi, a river that drains a part of the western Moroccan Meseta. The study used the colorimetric monitoring method, which quantifies the volumes of coarse sediment that were transported by monitoring topographic variations in the riverbed and measuring the distances covered by the sediment. The study showed the sediment was found to move around seven times annually on average. However, the frequency and magnitude of floods and the size of particles affect the variation in this displacement. It also showed sediments travel an average distance ranging from 649 to 883 meters per year, and that the average specific bedload at the watershed scale is 30 m3/ Km2/ year. Relationships between flood peaks mobilized sediment volumes, and average particle distances are established and discussed. These results are fundamental to understanding of coarse sediment transfer processes in the small rivers of the central plateau. They are also essential for assessing the impact on the aquatic ecosystem, on downstream dams, and on the various existing road and hydro-agricultural infrastructures. This assessment will enable the implementation of appropriate management strategies to anticipate changes and plan the planning of the river and its watershed.