DOI: https://doi.org/10.55373/mjchem.v26i5.165

Keywords: Heavy metals; Heavy Metal Pollution Index (HPI); river water quality; water quality

Abstract

A study was carried out on water quality and heavy metal concentration in the Tengi River near Tanjong Karang, Selangor. Tanjong Karang is known for its fishing industry, agriculture and economic activities. Therefore, due to the human activities in this area, monitoring the water quality and heavy metal concentration is crucial. The samples were collected using water sampler, which was then acidified until pH 2 and filtered using cellulose acetate 0.45 µm. The concentration of heavy metals was determined using inductively coupled plasma optical emission spectroscopy (ICP-OES). The water quality parameters mean values for DO (5.8 mg/L), pH (8.4), TDS (287.4 mg/L), salinity (32.0 mg/L), and temperature (30.7℃) was obtained. While, the mean values for COD, BOD, TSS, and NH3-N were, 27.09 mg/L, 1.10 mg/L, 61.42 mg/L, and 2.32 mg/L, respectively. According to the results, all sites were categorized as CLASS IV except Site 3 and 14. A lower WQI number indicates that the river is more polluted. All sample locations are classified as contaminated ranges in the range of 0 to 59 by the DOE Water Quality Index Classification. The mean concentrations of Pb, Zn, and As were significantly lower than the Malaysian National Water Standard, with a mean value of 36.07 µg/L, 5, 211.47 µg/L, and 10.87 µg/L, respectively. In general, the concentration of heavy metals in river water was found to decrease in the following order: Zn > Pb > As. All the HPI values in fifteen sampling locations exceed 100. All the HPI values in fifteen sampling cites exceeded 100, indicating that the water HPI was above the critical limit (HPI > 100), hence unfit for drinking. This study may serve as a template for future research in terms of methodology and assist in the identification of the sources, water quality, and effects on the waterways of the Tengi River.