Efficient and resilient techniques for handling samples are essential for detecting pharmaceutical compounds in the environment. This study explores a method for preserving water samples during transport before quantitative analysis. The study investigates the stability of 17α-ethynylestradiol (EE2), acetaminophen (ACM), oxytetracycline (OTC), sulfamethoxazole (SMX), and trimethoprim (TMP) after preconcentration within solid-phase extraction (SPE) cartridges. Through various experiments involving different holding times and storage temperatures, it was determined that four pharmaceutical compounds remained stable when stored for a month at 4C and for six months when stored at 18C in darkness. Storing these compounds in SPE cartridges at 18C seemed effective in preserving them for extended periods. In addition, ACM, TMP, OTC, EE2, and SMX remained stable for three days at room temperature. These findings establish guidelines for appropriate storage and handling practices of pharmaceutical compounds preconcentrated from aqueous environmental samples using SPE.

Many approaches have been investigated to eliminate pharmaceuticals in wastewater treatment plants during the last decades. However, a lack of sustainable and efficient solutions exists for the removal of hormones by advanced oxidation processes. The aim of this study was to synthesize and test new photoactive bio composites for the elimination of these molecules in wastewater effluents. The new materials were obtained from the activated carbon (AC) of Arganian spinosa tree nutshells and titanium tetrachloride by the sol gel method. SEM analysis allowed one to confirm the formation of TiO₂ particles homogeneously dispersed at the surface of AC with a controlled titanium dioxide mass ratio, a specific TiO₂ anatase structure, and a highly specific surface area, evidenced by ATG, XRD, and BET analysis, respectively. The obtained composites were revealed to quantitatively absorb carbamazepine (CBZ), which is used as a referred pharmaceutical, and leading to its total elimination after 40 min under irradiation with the most effective material. TiO₂ high content disfavors CBZ adsorption but improves its degradation. In the presence of the composite, three hormones (17α-ethinylestradiol, estrone, and β-estradiol) are partially adsorbed onto the composite and totally degraded after 60 min under UV light exposure. This study constitutes a promising solution for the efficient treatment of wastewater contaminated by hormones.

Small Island Developing States (SIDS) face unique challenges for microplastics (MPs) monitoring due to limited infrastructure and resources. In this context, we propose and test innovative approaches toward a standardized, low-cost methodology for quantifying MPs in SIDS. We evaluate the giant clam T. maxima as a bio-integrator, combining Nile red (NR) fluorescence staining with automated machine-learning detection. We optimized a digestion protocol using KOH and HNO ₃ for T. maxima viscera, and developed a DAPI-guided multi-spectra composite imaging approach based on triband fluorescence (DAPI, FITC, TRITC), to enhance polymer detection while reducing blooming artifacts. A semi-automated annotation pipeline using Labkit interactive segmentation with CLIP/UMAP clustering efficiently generated training data from 6711 fluorescence images. A U-Net model was trained on composite images to segment fluorescent particles. The workflow was applied to giant clams from three French Polynesian islands (Makemo, Hao, Tubuai), and NR-based estimates were validated against µFTIR spectroscopy. The model achieved F1-scores of 0.741 for giant clam samples and 0.657 for controls, comparable to human annotation (F1 = 0.680). MPs were detected across all islands, with highest concentrations in gills (16.9–52.7 particles·g ⁻¹ wet weight) compared to viscera (2.5–11.0 particles·g ⁻¹ ww). µFTIR validation revealed that NR overestimates MP counts (µFTIR: 0.80 ± 0.16 particles·g ⁻¹ ww at Tubuai), primarily due to false positives from proteins, cellulose, and stearates. In Tubuai, polyamide (28.9%), PVC (12.6%), and polystyrene (10.7%) were the dominant polymers, suggesting contributions from fishing gear, agriculture, and household waste. While NR-based quantification overestimates absolute MP counts, the automated pipeline demonstrates potential for high-throughput image processing, reproducible sample analysis, and methodological standardization. This workflow represents a first step toward scalable, low-cost approaches for MPs monitoring in insular systems, highlighting areas for further calibration and optimization. Future work should refine fluorescence thresholds and expand validation across species and locations.