Geochemistry pollution status and contamination assessment of potentially toxic metals from the sediments of a tropical river of Kerala, India

Abstract

The contamination of heavy metals within the sediments of a tropical river basin of Kerala, India were studied using pollution indices thereby to examine the level of deterioration. Sediment samples were taken from 20 locations and the major investigations carried out in the sediment samples include geochemical analysis for the determination of major ions and minor (trace) elements by using X-Ray Fluorescence spectrometer (XRF) and textural analysis for the classification of sediment samples into different categories. To understand the pollution loads in the sediments of the study area, the heavy metal and major element contamination of the samples were assessed based on Crustal Enrichment Factor (EFc), geo accumulation index (Igeo), Contamination Factor (CF), Degree of contamination (Cdeg) and Pollution Load Index (PLI). From the analysis, it is seen that the coastal sediments of KRB were polluted mainly by Zirconium which exhibits high values in the pre monsoon season. Among the major elements, Titanium is the only one which manifests slightly higher values in the pre monsoon period. Based on the textural analysis, it is observed that these sediments predominantly come under sandy loam and loamy silt classifications during the three seasons of study. The unplanned urbanization and industrialization have detrimental effects on the quality of river sediments in the recent years. The current work is preferably applied to a river system and the findings will deliver productive evidence for analyzing the plenary catchment areas of Western Ghats.