Keywords: Heavy metal; pollution index; ICP-OES; Selangor river; WQI

Abstract

From a practical and strategic point of view, the Selangor River is crucial to Malaysia's water supply. The nature of the principal pollutant sources may change from rural to industrial, causing a wide range of environmental problems and competing priorities among water users. The Water Quality Index (WQI) is a numerical metric used to evaluate and describe the overall quality of water in a given water body such as river, lake, or ocean. It is calculated by taking into account on several physical, chemical, and biological parameters/factors (turbidity, pH, total nitrogen, COD, BOD) that are known to impact the suitability of water for various uses, such as consumption/ drinking, household chores, irrigation, recreation, and aquatic life. This study was conducted to determine the water quality status of Selangor River. Water sampling was conducted at ten (10) different locations during October 2022. Heavy metals such as Nickel (Ni), Lead (Pb), and Zinc (Zn) were analysed using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). This study found that the water quality index of Selangor River was classified as Class III, which was considered slightly polluted according to the classification of WQI. The mean concentrations of Ni, Pb, and Zn in Selangor River were 1.4±0.07 µg/L, 17.50±0.66 µg/L, and 5.67±0.13 µg/L, respectively. Moreover, a positive and robust significant correlation was identified between temperature and COD, BOD5 with TSS, and Ni, as well as between Ni and Ammoniacal Nitrogen (AN). The results of this study could be useful to the authorities and government in carrying out continuous environmental assessments so that our pollution levels can be monitored.