Distributions of Chromium, Copper, and Cadmium in the estuary-coastal surface sediment of Tin-Rich Island

Abstract

Belitung Island known as one of the tin producer in the world, as it lied in the South East Asian tin belt. The study was conducted in the North Belitung Island to investigate some metal elements concentration of sediment along the estuary river and coastal area near to carbonate reef environment system. Thirteen sediment samples were collected from estuarine riverbed, shoreline, and offshore of North Belitung. The concentrations of metal elements were analysed to assess the environmental pollution characteristics by using flame AAS (Atomic Absorption Spectrophotometry) method. The result indicated that the average concentrations of chromium (Cr), copper (Cu), and cadmium (Cd) were 1.62-18.26, 5.72-80.07, and 1.4-4.59 mg/kg dry weight, respectively. The calculation of geo-accumulation index (Igeo) was adopted in this study to evaluate the heavy metal pollution. The Igeo values revealed that this research area has been moderately polluted by Cr and Cu, and unpolluted-moderately polluted by Cd. Based on the contamination level to adverse biological effect, the heavy metals concentration in this research area has the low potential to adverse biological effect by Cr and Cu, and low-moderately potential by Cd. This information is important to lead the study about any other elements and heavy metals to evaluate the risk assessment in the tropical area.