Mercury (Hg) contamination in river water, well water, sediment and fish in Kuantan River, Riau

Illegal gold mining activities still frequently occur in the Kuantan River, which is one of the main rivers in the district of Kuantan Singingi, Riau. This activity causes environmental contamination of mercury (Hg). The objective of this research was to determine the contamination of Hg in river water, well water, sediment and fish (baung and kapiek) in the Kuantan River, Riau. Samples were taken at up, middle and downstreams of the Kuantan River. Mercury was analized by following APHA and Indonesian National Standard (SNI) methods. The results were compared with the quality standard of pollution. The results showed that average of Hg concentration in river water, well water, sediment and fish were 0,0325 mg/l, 0,0202 – 0,0231 mg/l, 0,2083 mg/kg, 0,1141 - 0,1224 mg/kg. Statistical analysis indicated that the concentration of Hg in river water, well water (middle and downstream) and sediment were above the quality standard, while in the samples of baung and kapiek were below the quality standard. Hg concentrations significantly increased from up to downstream locations in river water and sediment, Hg concentrations significantly increased in 2 community wells in middle and downstream locations, significant Hg concentration was found in kapiek caught in midstream locations, while there was no significantly at the Hg concentration of baung in the research location.   &nbsp