Geogenic versus Anthropogenic Sources of Hazardous Elements Pollution in Marine Sediment Samples: Case of Lampung Bay, Indonesia

Hazardous elements in the marine environment potentially affect the safety of seafood production in the area. Some elements are considered as essential elements for humans in a low concentration, but some others are toxic and believed to induce cancer even though at a trace level. This paper has studied the source of hazardous elements contamination in Lampung Bay, Indonesia, whether anthropogenic or geogenic. Sampling was conducted at a one-mile distance from the shore. Some stations were also located in the river mouth to investigate how much inland pollution affects the bay. The mean enrichment factor (EF) for each hazardous element are 0.62, 3.09, 2.79, 4.18, 2.03, 6.10, and 2.05 for Cr, Ni, Cu, Zn, Cd, As and Pb, respectively, showing that all elements influenced by anthropogenic source except Cr. This result is proven by the lower geo-accumulation index (Igeo) normalisation, meaning the influence of geogenic sources is limited. Further statistical analysis using principal component analysis (PCA) showed that the river mouth sampling stations influenced the concentration of hazardous elements in the bay. Although the concentration of the elements is below the maximum level of the quality standard for marine sediment in almost all sampling stations, continuing monitoring of the environmental healthiness of the bay is encouraged to ensure the sustainability of fisheries production in this area.