Extraction of heavy metals characteristics of the 2011 Tohoku tsunami deposits using multiple classification analysis

Kengo Nakamura, Tatsu Kuwatani, Yoshishige Kawabe, Takeshi Komai

Research output: Contribution to journalArticlepeer-review

17 Citations (Scopus)

Abstract

Tsunami deposits accumulated on the Tohoku coastal area in Japan due to the impact of the Tohoku-oki earthquake. In the study reported in this paper, we applied principal component analysis (PCA) and cluster analysis (CA) to determine the concentrations of heavy metals in tsunami deposits that had been diluted with water or digested using 1 M HCl. The results suggest that the environmental risk is relatively low, evidenced by the following geometric mean concentrations: Pb, 16 mg kg-1 and 0.003 ml L-1; As, 1.8 mg kg-1 and 0.004 ml L-1; and Cd, 0.17 mg kg-1 and 0.0001 ml L-1. CA was performed after outliers were excluded using PCA. The analysis grouped the concentrations of heavy metals for leaching in water and acid. For the acid case, the first cluster contained Ni, Fe, Cd, Cu, Al, Cr, Zn, and Mn; while the second contained Pb, Sb, As, and Mo. For water, the first cluster contained Ni, Fe, Al, and Cr; and the second cluster contained Mo, Sb, As, Cu, Zn, Pb, and Mn. Statistical analysis revealed that the typical toxic elements, As, Pb, and Cd have steady correlations for acid leaching but are relatively sparse for water leaching. Pb and As from the tsunami deposits seemed to reveal a kind of redox elution mechanism using 1 M HCl.

Original languageEnglish
Pages (from-to)1241-1248
Number of pages8
JournalChemosphere
Volume144
DOIs
Publication statusPublished - 2016 Feb 1

Keywords

  • Cluster analysis
  • Heavy metal
  • Principal component analysis
  • Tohoku-oki tsunami deposit

ASJC Scopus subject areas

  • Environmental Engineering
  • Environmental Chemistry
  • Chemistry(all)
  • Pollution
  • Health, Toxicology and Mutagenesis

Fingerprint

Dive into the research topics of 'Extraction of heavy metals characteristics of the 2011 Tohoku tsunami deposits using multiple classification analysis'. Together they form a unique fingerprint.

Cite this