The long term tsunami impact: Evolution of iron speciation and major elements concentration in tsunami deposits from Thailand

A Fast and Efficient Procedure of Iron Species Determination Based on HPLC with a Short Column and Detection in High Resolution ICP OES

The optimization and application of a new hyphenated procedure for iron ionic speciation, i.e., high performance liquid chromatography (HPLC) with short cation-exchange column (50 mm × 4 mm) coupled to high resolution inductively coupled plasma optical emission spectrometry (ICP hrOES), is presented in this paper. Fe(III) and Fe(II) species were separated on the column with the mobile phase containing pyridine-2,6-dicarboxylic acid (PDCA). The total time of the analysis was approx. 5 min, with a significantly low eluent flow rate (0.5 mL min^-1) compared to the literature. Additionally, a long cation-exchange column (250 mm × 4.0 mm) was used as reference. Depending on the total iron content in the sample, two plasma views were chosen, e.g., an attenuated axial (<2 g kg^-1) and an attenuated radial. The standard addition method was performed for the method's accuracy studies, and the applicability was presented on three types of samples: sediments, soils, and archaeological pottery. This study introduces a fast, efficient, and green method for leachable iron speciation in both geological and pottery samples.

Distribution of plastic litter in beach sediments of Silver beach, Cuddalore, during Nivar Cyclone - A first report

The present study was conducted to assess the distribution of plastic debris in pre- and post-cyclonic beach sediments in Silver beach, Cuddalore, southeast coast of India. The total amount of macroplastic in pre-cyclonic beach sediments was higher than that in the post-cyclonic coastal sediments (pre-cyclonic 16.1%; post-cyclonic 5.4%). The polymer varieties in pre- and post-cyclonic sediments were present in the following descending order: Pre-cyclonic sediments: polyvinyl chloride (79.06%) > polyethylene (13.9%) > nylon (6.9%); post cyclonic sediments: polypropylene (31.4%) > polyethylene (30.5%) > polystyrene (16.0) > nylon (15.5%) > polyvinyl chloride (5.1%). The different varieties of polymers with irregular shapes in the sediments are most probably introduced into the coastal environment by cyclonic floods. Wind and cyclone-induced rainfall were the driving forces for the transportation and deposition of plastic debris. The results of this study will be useful to formulate effective beach litter management policies in an attempt to develop long-term solutions.

Post-depositional changes in elemental leaching from recovered soils separated from disaster waste and tsunami deposits generated by the Great East Japan Earthquake and tsunami

The Great East Japan Earthquake and subsequent tsunami in 2011 generated massive amounts of disaster waste and tsunami deposits, one-third of which comprised soil and sediment, which are expected to be re-used; however, there has been no previous experience or knowledge of recovered soil. In this study, up-flow column leaching tests were conducted to investigate the elemental leaching behavior in this soil and sediment following its separation and treatment (hereafter termed "recovered soil") to assess whether it can be safely re-used without posing any environmental risk. The pH of the leaching water was slightly alkaline throughout the test period, regardless of the source of the recovered soil. Concentrations of calcium and sulfate ions in the leaching water varied in a similar way to the electrical conductivity (EC), with a stable state being observed initially followed by a rapid decrease until typical concentrations were reached, whereas sodium and chloride ions derived from seawater made a relatively small contribution to the EC. In terms of toxic elements, zinc and copper concentrations decreased as the volume of leaching water increased, whereas lead, fluoride, and arsenic concentrations increased as the concentration of calcium and sulfate ions decreased, indicating that the dissolution of large quantities of compounds such as calcium sulfate controlled the toxic element behavior in the recovered soils. Consequently, there is a need for continuous and careful monitoring of areas where recovered soil is re-used or treatment of the recovered soil prior to its re-use.