Quality indicators of metals pollution in the coastal sediments in Sangihe Islands Regency, North Sulawesi Province, Indonesia

Abstract

Metal pollution in coastal areas is one of the focused environmental concerns. Sediment quality in the coastal zone reflects the long-term environmental status because it keeps a record of the development in the area. Quality indicators for metals in surface sediments were evaluated at 18 points of sediment sampling sites of these three bays using the Enrichment factor (EF) and the geo accumulation index (Igeo). Research locations in the coastal areas of Sangihe Island, Talengan Bay, Manalu, and Dagho Bay have values below the metal concentration at the background value. The Igeo category at the three research sites can generally be divided into two criteria, namely: Background concentration and unpolluted. For the types of Cr and Mg metals that are categorized as experiencing enrichment Minimum enrichment (Less), with an EF value <2, Moderate enrichment (Moderate), with a value of 2≤EF <5, and Enough enrichment (significant), with a value of 5≤EF <20. Whereas Co metal experiences enrichment of Very High enrichment (Very High), with a value of 20≤ EF < 40, and Extremely High (extremely high), with an EF value of ≥40, but still has an igeo value <1 which indicates that the metal Co is still in the category of no pollution.