Surface water samples were collected from 16 Lakes in and around Miri City to assess the electrochemical parameters includes pH, Electrical conductivity (EC), Total dissolved solid (TDS), redox potential (Eh), resistivity and salinity. Sampling locations for monitoring were selected in the vicinity of major roads, industries, settlements and agricultural region. Interpretation of data shows that the surface water in the central region of the study area is polluted by various anthropogenic activities, while in the southern part is within the limits of guideline values. This kind of investigation is essential in the study area to save the resources for future perspective. Further detailed studies are also needed to get a clear picture of the surface water quality in Miri city and for future sustainable management of this resource.
The composite nature of Ennore Creek, receiving polluted waters from Buckingham canal, River Kortalaiyar, and the presence of numerous industries rapidly degrade the coastal environment. In this study, multivariate statistical technique was used to assess the nature of pollution and to identify the factors responsible for the enrichment of trace metals in the creek sediments. Forty samples were collected during pre- and post-monsoon periods to evaluate the seasonal variations on the concentration of trace metals in the sediments. The results indicate that not much seasonal variation exists in the concentration of trace metals in the sediments of Ennore creek. Results of the cluster analysis illustrate that the enrichment of trace metals was mainly from anthropogenic sources. Meanwhile, correlation coefficient among the metals reveals that some of the metals (Fe and Al) derived were of natural origin. The complex data matrix of the sediment were interpreted after reduction to three factors and the results illustrate the extent of the influence of anthropogenic activities. The spatial distribution diagrams demonstrate and demarcate the region of enrichment of metals in the sediments of Ennore creek.
The concentrations of nine trace metals (Cr, Mn, Co, Ni, Cu, Zn, Rb, Cd, and Pb) were measured in different tissues of two pelagic and five demersal fish species collected from the Miri coast, Sarawak. The sequence of accumulation of trace metals in different tissues were: liver > gill > gonad > muscle. Zn (301.00 μg g-1) and Cd (0.10 μg g-1) was the maximum and minimum accumulated elements. According to the Hazard Index calculation, none of the elements will pose any adverse health effects to humans for both ingestion rates (normal and habitual fish consumers) proposed by USEPA, except for Pb and Cd in certain fish species. On the basis of the results, the level of elements in the edible muscle tissues of all the analyzed fish species from the Miri coast are below the maximum permissible limits of Malaysian and International seafood guideline values and safe for consumers.