Heavy metal distribution in sediments around the offshore tin mining area of Central Bangka Regency, Indonesia

Vary heavy metals scattered in suspension loads and re-sedimentation from the tailing of the offshore-alluvial tin mining at Tanah Merah and its surroundings, Central Bangka Regency. Research is needed to determine the type, composition, spatial distribution of heavy metals, and potential pollution. The active surface-sediments were taken from shallow marine systematically around the offshore tin mining area in the east season. Geochemical analysis of sediment using x-ray fluorescence, coupled with minerals and sieve analysis, and support by spatial analysis. These sediments have dominant the sand-size (range very-fine sand to coarse sand) and silt, contained predominantly large quantities of quartz minerals and shell fragments of marine animals. The metals are in the following decreasing order: Cr>Zn>Pb>Ni>Cu>As>Co>Cd. The spatial distribution of heavy metals generally has a relatively south, east, and north position, with concentrations occurring along the coastline and showing the degradation composition towards the open sea. The marine sediments are uncontaminated to moderately contaminated by Cd and Pb, indicate both natural and anthropogenic enrichment, low the pollution load index (PLI), and have various potential ecological risks index (RI) (low to very high RI).