Search

The total concentrations of metal are seldom useful in determining its biological availability. A BCR sequential extraction procedure was applied for fractionation of heavy metals Cu, Ni, and Zn in sediment. Surface sediment samples were collected at 27 sites in Cirebon coastal waters, West Java, Indonesia in April 2017. The aim of this study to determine metal fractionation and to evaluate bioavailability in the sediments from Cirebon coastal waters. The result showed that 44.2% fraction of Cu, 35.7% fraction of Ni and 44.8% fraction of Zn were the non-residual fraction, this suggests that the metals Cu, Ni, and Zn were from anthropogenic. It is indicated that the metals are potentially available existence to exchange into the marine environment. The sediments showed a low and medium risk for Cu (1.85 to 6.71%) and Zn (4.14 - 13.1%) with RAC values of less than 10%, but the medium risk for Ni (7.45-16,7%). There is no any element in the selected samples in category very high-risk conditions.

Metals are bound to a different phase in sediment and that speciation reflects their bioavailability for an organism. The speciation of Cu and Ni in sediment in Benoa Bay, Bali was not well investigated. Thus, this study was aimed to determine Cu and Ni speciation in sediment from Benoa Bay, Bali and to assess their mobility. Sediment samples were collected from 11 observation points (stations) in Benoa Bay in March 2017. Modified BCR (Community Bureau of Reference) protocol was applied to extract different Cu and Ni species in the sediment namely metal associated with carbonate fraction (F1), iron/manganese oxide (F2), organic and sulfides (F3) and mineral (F4). The result revealed that Cu was dominantly associated with mineral (>50% of Cu in F4), therefore, Cu resembled the lithogenic origin. Opposite, Ni was associated with carbonate and iron/manganese oxide almost in all observation points indicating anthropogenic origin. Risk assessment code (RAC) was computed to determine the possibility of that Cu ...