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This study assesses the spatial distribution and contamination level of heavy metals in Safi Bay surface sediments. In this order, 28 surface sediment samples were retrieved from the study area and analyzed using the x-fluorescence method. To assess the contamination of the examined sediment, we used geo-ecological indices such as contamination factor (CF), degree of contamination (DC), geo accumulation index, and pollution load index (PLI). The results show that only Pb and Cd present moderate and considerable contamination in some sampling sites, while other elements (Cr, Cu, Zn, and Ni) indicate no contamination and low contamination by these elements. The inhomogeneous distribution of metal concentrations along the bay suggests different heavy metal sources. Given the ecological and socioeconomic importance of the study area, there is a need for a further analysis of both sediments and biological samples for a better understanding of the contamination levels and origin of metals, in addition to the sustainability of Safi Bay. [ABSTRACT FROM AUTHOR]

Phytoliths are essential palaeoecological proxies that play an immensely important role in palaeoclimatic studies. Their inert composition and general hardiness allow phytoliths to be preserved in geological settings, even when other plant fossils perish. This partially explains their utility for investigating plant communities and plant-human interactions on short and long timescales. Phytoliths also happen to be the most reliable source of fossil evidence for tracking the evolutionary history of grasses, arguably among the most crucial extant plant families. In the last two decades, the number of studies and publications in all fields of phytolith analysis has grown exponentially, mainly due to a diversification of research topics. Although significant progress has been made in applying phytolith analysis to answer archaeological, palaeoenvironmental, palaeoclimatological, evolutionary, and taxonomic questions, phytolith assemblages can be subject to pre- and post-depositional processes that might affect their preservation and thus could bias interpretation. This article reviews the importance of phytolith research in palaeoecology, discusses the constraints and taphonomic processes affecting phytolith analysis, and highlights the challenges in phytolith studies across various sediments. It emphasizes the significance of identifying phytolith transportation modes and understanding the impacts of taphonomic processes. Specific sampling strategies, such as targeting environments protected from surface weather conditions and selecting sediments with lower translocation rates or little horizon development, are suggested to preserve a diverse range of phytolith morphotypes. Caves and deltas are proposed as suitable alternatives to neritic marine sediments and carbonate-rich sites. This review also emphasizes the importance of sediment analysis, including grain size, sediment transport trend analysis, and micromorphology, complemented by analytical techniques and multi-proxy approaches. The inclusion of thin section studies, micromorphology, SEM, EDS, FT-IR, XRD, AAS/AES, XRF, and ICP-MS/AES is recommended to minimize depositional biases and help understand biases related to phytolith formation. Using mathematical models and correlation measurements to assess the impact of taphonomy on phytolith assemblages is also valuable. To conclude, we discuss some analytical considerations and suggest a methodological framework that integrates phytolith analysis with a sedimentological perspective. This approach aims to minimize the biases in phytolith analysis and enhance our understanding of palaeoecology. [ABSTRACT FROM AUTHOR]

The sustainable management of dredged sediment from contaminated sites needs to consider the end-use of the treated sediment. In this regard, modifying conventional sediment treatment techniques to generate a product that is suitable for a range of terrestrial uses is necessary. In the present study, we evaluated the product quality of treated sediment as a potential plant-growth medium following the thermal treatment of marine sediment contaminated by petroleum. The contaminated sediment was subject to thermal treatment at temperatures of 300, 400, or 500 °C, and no, low, or moderate oxygen availability, and the resulting treated sediment was analyzed in terms of its bulk properties, spectroscopic properties, organic contaminants, water-soluble salts and organic matter, and the leachability and extractability of heavy metals. All operational combinations for the treatment process reduced the total petroleum hydrocarbon content of the sediment from 4922 mg kg−1 to lower than 50 mg kg−1. The thermal treatment process stabilized the heavy metals in the sediment, reducing the zinc and copper concentration by up to 58.9% and 89.6%, respectively, in the leachate from the toxicity characteristic leaching procedure. The hydrophilic organic and/or sulfate salt byproducts of the treatment were phytotoxic, but these can easily be removed by washing the sediment with water. By combining the sediment analysis results with experimental data from barley germination and early-growth tests, the end product was found to be of higher quality when higher temperatures and lower oxygen availability were employed in the treatment process. These findings demonstrate that it is possible to retain the natural organic resources of the original sediment by optimizing the thermal treatment, thus ensuring a suitably high product quality for use as a plant-growth medium. [Display omitted] • Quality of thermally treated marine sediment was comprehensively evaluated. • Oxygen availability and temperature strongly affect the treated sediment quality. • Thermal treatment stabilizes metals while producing water-soluble toxicants. • Water-washing post-treatment enables producing high-quality media for plant growth. • For product quality pyrolytic conditions are superior to oxidative conditions. [ABSTRACT FROM AUTHOR]

Radioecological studies have been carried out in area of Gela Phosphate Industry. As a part of the project, some achievements have been described in the paper, including: (1) determination of the activity concentrations of 210Po, 210Pb, uranium, and radium isotopes in phosphogypsum, phosphoric acid, soil, and marine sediment, (2) inventory estimation of the NORM in the residual product and by-product, and (3) the radioecological investigation and evaluation on the NORM contamination in the sea area of Gela. The obtained data showed that the 210Po, 210Pb, uranium, and radium isotope contamination due to discharge of phosphogypsum from 1960s to 1990s is not observable through sediment analyses. • The concentrations of 210Po, 210Pb, 212Pb, uranium and thorium isotopes in phosphogypsum and sediment were determination. • The inventory of the NORM in the residual phosphoric acid and by-product was estimated. • The radioecological impacts of the NORM contamination on the sea area of Gela were assessed. [ABSTRACT FROM AUTHOR]

Currently, there are many contaminants of concern that need to be accurately determined to help assess their potential environmental hazard. Despite their increasing interest, yet few environmental occurrence data exist, likely because they are present at low levels and in very complex matrices. Therefore, multiresidue analytical methods for their determination need to be highly sensitive, selective, and robust. Particularly, due to the trace levels of these chemicals in the environment, an extensive extraction procedure is required before determination. This work details the development of a fast and cheap vortex-assisted matrix solid-phase dispersion-high performance liquid chromatography tandem-mass spectrometry (VA-MSPD-HPLC-MS/MS) method for multiresidue determination of 59 contaminants of emerging concern (CECs) including pharmaceuticals, personal care products, and booster biocides, in sediment. The validated method provided high sensitivity (0.42–36.8 ngg−1 dw quantification limits), wide and good linearity (r2 > 0.999), satisfactory accuracy (60–140%), and precision below 20% for most target analytes. In comparison with previous methods, relying on traditional techniques, the proposed method demonstrated to be more environmentally friendly, cheaper, simpler, and faster. The method was applied to monitor the occurrence of these compounds in sediments collected in Brazil, using only 2 g dw sediment samples, free-solid support, and 5 mL methanol as extraction solvent. The UV filter avobenzone, the UV stabilizer and antifreeze methylbenzotriazole, the preservative methylparaben, the fluoroquinolone antibiotic ciprofloxacin, and the biocides irgarol and 4,5-dichloro-2-octyl-4-isothiazolin-3-one were determined at concentrations in the range 1.44–69.7 ngg−1 dw. Image 1 • A method for 59 emerging organic contaminants analysis in sediments was developed. • Matrix solid phase dispersion allowed limits of quantification of 0.42 ngg−1dw. • The validated method was applied to analyze marine sediments from Brazil. • Detected analytes were measured at concentrations between 1.44 and 69.69 ng g−1dw. [ABSTRACT FROM AUTHOR]