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The level of metallic (Cd, Ni, Fe, Pb, Cu) contamination in the sampled sediments of five stations (S1, S2, S3, S4 and S5) from Woji creek bed between August and October 2019 was appraised using pollution load index (PLI), contamination factor (CF) and geoaccumulation index (Igeo). Results from the sediment analysis showed that Cd was not detected in stations 1, 3 and 5 in September, however, there was a high concentration of Cd in station 3 in October (43.590 ± 2.013 mg/kg). The concentration of Ni was highest in station 4 in August (247.682 ± 6.026 mg/kg). The mean spatial concentration of Pb ranged from 57.774 ± 75.647 mg/kg in October to 344.153 ± 112.184 mg/kg in August. Spatially, the highest concentration of Fe was measured in August (23.945 ± 17.828 mg/kg). Station 2 had the lowest concentration of Fe in the sediment temporally (5.667 ± 6.381 mg/kg) while station 3 had the highest concentration (19.496 ± 24.090 mg/kg); 37.188 ± 27.821 mg/kg (station 3) was the highest mean temporal concentration Cu, while station 2 had the lowest mean concentration of Cu (0.471 ± 0.358 mg/kg).The PLI values were in the trend: S3 (2.58 x 1015) >S4 (5.29 x 1014) > S1 (3.52 x 1014) > S5 (3.71 x 1013) > S2 (4.64 x 1012).These results indicated that the highest concentration of studied metals was found in S3 (except for Ni in S4), which emphasised the possible input of metallic matter into the sediment from the various operations along the creek connected with the disposal of metallic particulate wastes. All the metals present in the sampled sediments (except for Cu in S2) had concentrations between threshold effect level (TEL) and probable effect levels (PEL), which suggests the influence of unfavourable biological processes taking place from time to time. [ABSTRACT FROM AUTHOR]

As one of the most important margin seas around the west Pacific, the eastern China seas are important sink for terrigenous materials and forms multiple geology structures. So research the composition and spatial distribution of sediments could help us to understand the dynamics mechanism of the marine sedimentary environment, further to comprehend the land-sea interaction process. Based on high spatial resolution sediment survey in the eastern China seas, the distribution diagram of the sediment types was compiled to reveal the space regularities of sediment. In this study, the Principal Component Analysis (PCA) method was used to identify the controlling factors that are the main controls of the sediment distribution in the study area, which revealed three factors (F1, F2 and –F1) representing grain size categories of >5.75φ, 4.25–5.75φ and 1.50–3.00φ, respectively. F1 represents fine sediments (>5.75φ), -F1 represents coarse sediments (1.50–3.00φ), and F2 represents intermediate-sized sediments (4.25–5.75φ). The sediment transport patterns of the different grain size categories in the eastern China seas are discussed in the context of a comprehensive analysis of sediment grain size composition, material sources, flow patterns, and other factors. The results show that fine-grained sediments represent a "distant" sink of terrigenous material that formed in a stable and low-energy sedimentary environment. The coarse sediment deposits were formed in the late Pleistocene when the hydrodynamic conditions were relatively strong, and the intermediate-sized sediments were distributed in an area with a high concentration of suspension representative of mid-strength hydrodynamic conditions. [Display omitted] [ABSTRACT FROM AUTHOR]

Heterocyclic aromatic compounds are organic contaminants present in low concentrations in sediments and include compounds containing N, S, and O atoms within a ring (NSO-HET). NSO-HETs have received increased scientific interest in the environmental pollution field because of their toxicity to ecosystems and towards humans. The lack of certified reference materials, the few authentic standards available, and the high number of potential isomers present challenges in the separation, identification, and quantitation these more polar polycyclic aromatic compounds analogue compounds. In this study, the sample preparation and instrumental methods to assess NSO-HET in sediments are reviewed, and the main advances and challenges are examined. The advantages and disadvantages of different analytical techniques, including classical and innovative approaches used to quantify and characterize NSO-HET in sediments, as well as the analytical quality control and availability of certified reference materials, are examined. Finally, future tendencies and challenges to be overcome are discussed. [Display omitted] • Properties and sources of major NSO-HET in sediment. • Extraction techniques for NSO-HET analysis in sediment. • Analytical methods for the determination of NSO-HET in sediment. • Future trends in the analysis of NSO-HET in sediment. [ABSTRACT FROM AUTHOR]

Atmospheric nuclear testing has occurred worldwide resulting in trace amounts of plutonium (Pu) isotopes in soils and sediments across the globe. Soils and sediments can vary greatly in both physical and chemical properties within close geographic regions presenting a major challenge for sample preparation in the analysis of fallout radionuclides. It is vital to have a rapid, agile method for the complete digestion of samples containing refractory Pu particles to address this challenge. A radioanalytical procedure for the analysis of Pu isotopes in soils/sediments has been developed improving sample preparation using fusion. This is done by eliminating the need for pre-dissolution combustion to remove organic material and providing greater application to a diverse range of samples including those of metal-bearing mineralogy. The integration of borate and peroxide flux materials creates a sample dissolution procedure that is greater than the sum of its parts. This method is applicable to the analysis of 239/240Pu in soil/sediment samples with a sample mass of 3 g, ranging from 0.05 to 5000 mBq/g achieving 242Pu tracer recoveries between 50 and 94%, with a trace-level detection limit of 0.04 mBq/g and measurement uncertainties down to 19%; adjustable to measurement priorities with variation in count time, background counts, chemical recovery and total activity of the sample. This sample preparation technique can be utilized with complementary analysis of alpha spectrometry or ICP-MS. Achieving these parameters provides a highly adaptable standard method for 239/240Pu in soil/sediment analysis applicable to samples from radioecological research at trace environmental levels to emergency response scenarios with 48-h turn-around producing highly repeatable, succinct and high-quality analysis. • An agile method for the analysis of refractory Pu particles in soils/sediments removing the need for pre-dissolution combustion. • Applicable to a diverse range of samples including metal-bearing mineralogy. • Validated for a range of 239/240Pu contamination (0.1–5000 mBq/g) achieving tracer recoveries between 50 and 94%, and a detection limit of 0.107 mBq/g using a combination of certified reference materials and real samples. • Highly adaptable method of analysis applicable to radioecological research at trace environmental levels and emergency response scenarios with 48-h turn-around producing highly repeatable, succinct and high-quality analysis. [ABSTRACT FROM AUTHOR]