ISSN 2375-088X
African Journal of Soil Science ISSN 2375-088X Vol. 7 (2), pp. 001-014, February, 2019. © International Scholars Journals
Full Length Research Paper
Fractionation profile and mobility pattern of trace metals in sediments of Nomi River, Tokyo, Japan
Shaila Sharmin1*, H. M. Zakir2 and Naotatsu Shikazono1
1Laboratory of Geochemistry, School of Science for Open and Environmental Systems, Faculty of Science and Technology, Keio University, Hiyoshi 3-14-1, Yokohama 223-8522, Japan.
2Department of Agricultural Chemistry, Faculty of Agriculture, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh.
Accepted 14 December, 2018
Abstract
This study provides a geochemical partitioning and mobility pattern of Iron (Fe), Manganese (Mn), Cadmium (Cd), Copper (Cu), Chromium (Cr) and Nickel (Ni) in sediment samples collected from Nomi River, Tokyo, Japan. For the partitioning of particulating trace metals, a widely used 5-step sequential extraction procedure was employed and the concentrations were measured in the liquid extracts by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Atomic Absorption Spectroscopy (AAS) to understand enrichment and metal availability in five geochemical phases. The association of Cd (39.8-89.7%) was found highest with adsorbed, exchangeable and carbonate (AEC) fraction, Fe (25 - 44.1%), Mn (11.8 - 76.7%), Cr (12.6 - 46.9%) and Ni (9.8 - 41.8%) were in residual phase and the maximum association of Cu was recorded with amorphous Fe Oxyhydroxide phase (24.7 - 51.3%). The order of potential trace metals mobility in the aquatic environment of Nomi River was- Cd > Cu > Cr > Ni > Fe > Mn. According to the risk assessment code applied in the present study Cu, Ni and Cr were under medium and Cd was under high risk category. The X-ray diffraction (XRD) study detected the presence of several clay minerals; those are likely to be the major host of trace metals in sediments.
Key words: Trace metal, fractionation, mobility, pollution, sediments, Nomi River, Tokyo.