Author(s): Yang Li
Email (s): email@example.com
Institution or organization of origin: University Putra Malaysia
Ex-mining lake have been linked with issues of poor water quality and elevated levels of heavy metal, but they are widely used by the local people for various activities including fisheries. This study was conducted to determine the physico-chemical parameters and the levels of iron (Fe), lead (Pb) and zinc (Zn) from an ex-mining lake. Triplicates lake water samples were collected from ten sampling points, covering both the littoral and limnetic zones of the lake. In-situ water quality parameters including dissolved oxygen, pH, salinity, electrical conductivity, temperature and turbidity were measured using a single or multi-probe meter, while water samples were collected in acid-washed bottles and preserved for further lab analyses.
Metal levels were determined using ICP-MS. The results obtained were compared with the National Lake Water Quality Standards (NLWQS) and National Water Quality Standards (NWQS) of Malaysia. In general, water quality at sampling point one (inlet) differed from other points (p<0.05). All physico-chemical water quality properties measured were within permissible limits of the standards except for dissolved oxygen and pH that exceeded the limit of NLWQS. The sequence for heavy metal levels were found to be in the trend of Fe > Zn > Pb with mean value of 0.372 mg/L, 0.005 mg/L and 0.038 mg/L, respectively. The concentration for all metals were found to be within the standard limit. Overall, the quality of the ex-mining lake was still within the safe limit. Further comprehensive studies incorporating more water quality parameters and metals are needed to complement the study.