Abstract
On 22 and 28 July 2007 we took samples from Lake Tilap, in the Rakumpit subdistrict of Central Kalimantan, Indonesia, to investigate the concentrations of mercury in water, sediment, phytoplankton, zooplankton, and fish species. Mercury concentrations in the samples were measured by heating evaporation mercury measurement equipment. Mercury was not detectable in surface water sample (≤ 0.002 μg/L), and level in sediment sample was 0.030 μg /g. Phytoplankton at depths of 7.5, 3.5, and 0.5 m contained 0.008 μg /g, 0.008 μg /g, and 0.051 μg /g, respectively. Overall, zooplankton had the highest concentrations of mercury (0.016-0.079 μg /g). Nine fish species were sampled. The total mercury concentration in fish muscle tissues ranged from 0.034 to 0.426 μg /g, and the juah (Luciosoma trinema) had the highest concentration.
