Distribution of mercury in sediment and oyster of Setiu Lagoon, Terengganu

Abstract

This study was conducted in order to determine the concentration of mercury in sediment and oyster from the Setiu Lagoon. Mercury was anaJyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). The mean concentration of mercury in the sediment during the dry season ranged from 0.024 ppm to 0.086 ppm and from 0.037 ppm to 0.337 ppm for the wet season. Sediment mercury concentrations were generaJly higher than the average of earth crust vaJue (0.08 ppm) at four of the six sampling sites in the lagoon. For the first sampling, the mercury concentration in oyster ranged from 0.074 ppm d.wt to 0.037 ppm d.wt and from 0.160 ppm d.wt to 0.075 ppm d.wt for the second sampling. There was no relationship in mercury concentration between sediment and oyster sample as r=0.141. While p>0.05 indicate that there is no significant difference in mercury content in sediment and oyster. ln addition to that, Setiu oyster mercury content was compared with permissible levels of the Malaysia Food Act. The samples were collected in the dry (August) and wet (November) seasons. The mercury concentration of oyster tissue in wet weight basis was still below the permissible levels of the MaJaysia Food Act (0.5 ppm) which was 0.012 ppm and 0.019 ppm for the dry and wet season respectively.