Investigating on water quality and radioactive elements in tracing the origin of pollutant at Gebeng Industrial area

Abstract

Extensive deterioration of water quality caused by the intensive land use activities in rivers and rapid response of pollutants from different sources may harm the aquatic organisms, human, and environment. This alarming occurrence has inspired the study to measure water quality parameters, the concentration of radioactive elements and heavy metals in surface water and sediment, and investigating the main sources of pollution in rivers. For achieving all these objectives, data collection was done for Balok and Tunggak Rivers in wet seasons for surface water while for sediment, only baseline data were collected. The data were compared and analyzed by using environmetric analysis (Cluster Analysis and Principal Component Analysis) based on different points at the selected rivers in Gebeng, Pahang. The physicochemical parameters such as temperature, specific conductivity, pH, turbidity, dissolved oxygen (DO), and salinity were measured by using the Hydrolab. The water and sediment samples were then collected for tracing the radioactive elements and heavy metals by using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Prior to analysis, the sediment samples were undergoing the full-digestion process. Both the Malaysian and International standards were used as a reference and it was found that water quality parameters were all within the permissible limit except for turbidity and specific conductivity. Besides, heavy metals and radioactive elements investigated in surface water showed that the concentration of Iron was exceeding the permissible limit at most of the sampling points and Thorium exceed the permissible limit at SB1 with value of 0.0005 ppm. While for sediment, the concentration of Iron was exceeding the permissible limit at the upstream area of both rivers and the concentration of Arsenic were exceeding at downstream area which recorded at 10.3713 ppm. Then, the finding from the environmetric analysis showed that the main pollutants loading in Balok and Tunggak River were Lead (first component), specific conductivity (second component), Thorium (third component), and pH (fourth component). The study outcomes showed that the presence of the pollutants in rivers were originated from both point and non-point sources.