Distribution of mercury in the Sungai Paka, Dungun, Terengganu

Abstract

Total mercury concentrations were determined in environmental samples such as sediment, water and biota from the river areas, and some contaminated sources common to the Paka ruver of Terengganu. Water, sediment, fishes, mangrove crab, river prawn were collected during pre and post monsoon from targeted areas affected by point and non-point source contaminants. Mean concentrations in water were 0.032 ± 0.015 µg C 1 during pre monsoon and were 0.013 ± 0.006 µg 1- during post monsoon season. Mean 1 concentrations in sediment were 0.338 µg g- 1 during pre monsoon and were 0.244 µg g- during post monsoon season. Mean total mercury concentrations in fish, mangrove crab, and river prawn were significantly lower than those in sediment. Mean concentrations 1 1 (µg g- dry wt) were 0.048 ± 0.027 µg g- 1 during pre monsoon and 0.030 ± 0.013 µg g- during post monsoon for all the biota samples. Spatial, intraspecific and interspecific variability in the results limited most generalizations concerning the relative mercury contributions of different stressor types. All residues of seafood were less than the US 1 Federal Drug Administration action limit of 1.0 µg g- for all biota samples.