Environmental Risks Assessment Of Total Mercury Accumulation At Sentani Lake Papua Indonesia

Abstract This study aimed to investigate the environmental risks of Total Mercury THg accumulation in Sentani Lake Papua Indonesia. THg was assessed around the Sentani Lake. Sampling survey for Water column sediment bivalve pelagic and benthic fishes samples were collected in one time collection. Furthermore and potential environmental and health risks were determined using hazard quotient HQ and target hazard quotient THQ equation. Results revealed the concentration of Hg in water column sediment bivalve pelagic and benthic fishes were ranged from 0.002 to 0.076 g L-1 115 to 184 g kg-1 dw 0.024 to 1.678 g kg-1 ww 0.017 to 1.265 g kg-1ww and 0.139 to 1.845 g kg-1ww respectively. The elevated values of Mercury concentrations were observed in sediment and benthic fish at the maximum concentrations of 1.678 g kg-1dw and 1.845 g kg-1ww respectively. The magnitude of environmental Hazard Quotient for water and sediment showed that 0.001 0.038 and 0.66 1.06 respectively. In addition the high values of target hazard quotient THQ for water column bivalve pelagic and benthic fishes were in the range of 0.004 to 0.252 0.005 to 0.190 and 0.024 to 0.277 respectively. All those levels have not exceeded the limit standard or 1 for potential health risks which mean safe for consumption. This study suggested that the magnitude of Hg concentration in Sentani Lake is generated primarily by the atmospheric fall down from some industries and amalgamation process where some people burn the gold ore. This area is surrounded by major number of Hg from industry and home scale industry directly emitted their waste to Sentani Lake. In case of health risks assessment by comparing with PTWIs and THQ based on the bivalve and fish consumption for 70 years life span of 60 kg body weight it indicated that people who consumed bivalve and fish from Sentani Lake were not at risk however they might be posed a risk due to the long and continual period of consumption.