Mercury bioaccumulation in crab and fish at Kayeli Bay, Buru Island

Abstract

In November 2011 gold was found in large quantities in Mount Botak, Buru Island, Moluccas Province. More recently mercury has been used in the trommel method to extract gold from ores. This method requires large volumes of water for flushing and results in the deposition of mercury into the upper catchment of the Wamsait river system, which flows to Kayeli Bay. Mercury and its derivatives have long been known to be very toxic so that its presence in the aquatic environment may have adverse effects on humans because it is easily soluble and bound in the body tissues of aquatic organisms. This study was conducted to analyze the levels of mercury in Giant mud crab (Scylla serrata) and Goldband goatfish (UpenusmoluccensisBlkr) in the Kayeli Bay. Samples of Giant mud crab and Goldband Goatfish mercury levels were then analyzed using a mercury analyzer to determine the amount of mercury. The analysis showed that mercury levels in Giant mud crab samples were 0.02 mg/Kg while mercury levels in Goldband goatfish seeds sample were 0.01 mg/Kg. Standard Nasional Indonesia (INS) or Indonesia National Standard stipulates that the threshold level of mercury in fishery products and processed products should be no higher than 0.5 mg/Kg. Although the mercury level found in Giant mud crab (Scylla serrata) and Goldband goatfish (UpenusmoluccensisBlkr) in the Kayeli is considerably low, it is quite alarming. The results of this study indicate that mercury has been concentrated in the body of Giant mud crab and Goldband goatfish.