Pollution Research Paper

ASSESSMENT OF SURFACE WATER METAL POLLUTION BASED ON POLLUTION LOAD INDEX (PLI) SUPPORTED BY MULTIVARIATE STATISTICAL ANALYSIS

MOHD ZAHARI ABDULLAH, NUR RASHIDAH ABD MANAP, AHMAD SAAT AND ZAINI HAMZAH

Abstract

This study was conducted to assess the distribution of selected metal concentrations in surface river water, which indirectly indicate the quality of studied river. Ten (10) stations were selected along the river and water samples in duplicates were collected using polyethylene bottle sampled during the pre-monsoon (October, 2013). The water samples were digested according to the standard method and were analyzed for Cd, Co, Cr, Cu, Li, Ni, Pb, and Zn using ICP-MS. The mean concentrations (ppb) of the respective metals were 0.11 ± 0.06, 8.67 ± 8.19, 4.80 ± 1.96, 31.26 ± 17.98, 64.11 ± 42.42, 17.99 ± 10.10, 4.81 ± 3.59, and 20.58 ± 16.07. The variation of heavy metals levels was very significant with the relative standard deviation measured were within 40.19 % (Cr) and 94.46 % (Co). Cd was found at the lowest concentration range while Li was the highest. The metals’ pollution was evaluated by contamination factor (CF) followed by pollution load index (PLI). The mean of CF clearly indicated that the river was extremely contaminated with Li but not with Pb. The high values of PLI index at all study stations strongly suggest that the river was polluted with the studied metals at a certain level. Cluster analysis (CA) and principal component analysis (PCA) were used to treat the data set. The results of CA and PCA clearly indicated that the metals were emitted by two different sources.