Pollution sources and ecological risks of potentially toxic metals in sediments from a multi-functional Hsingda Harbor in southwestern Taiwan

Sediment metal pollution was assessed in a multi-functional harbor in southwestern Taiwan, Hsingda Harbor, which was developed from a traditional fishing port. Contamination level and ecological risks were identified using multiple sediment pollution indices referenced from the total metal contents (Cu, Zn, Pb, Cr, Ni, Hg, and Ag) and their chemical partitioning factions. This study used local background, normalization with Fe content, and correlation with total organic carbon to differentiate between natural and anthropogenic sources. Results showed that fisheries-related activities and the nearby coal-fired power plant primarily contributed to potentially toxic metal pollution. Remarkably, Cu, Zn, Pb, Cr, and Hg contents in the sediments along the nearshore fishing port (77.7, 270, 50.4, 99.1, and 0.31 mg/kg) were up to 2.1-9.5 times higher the background site. Significant Cu and Pb enrichment (EF: 5.4-6.6) may be attributed to antifouling paints and coal ashes. The adjacent oyster farm sediments were enriched with Cu and Zn (EF: 2.5-4.5), potentially threatening the oyster quality and public health. Moderate-high and low ecological risks were obtained from the assessments of total metal contents (PERI: 116-340) and extractable fractions (GRI: 9.0-28.6), respectively. Using total metals and chemical partitioning data provides a better understanding of potential ecological risks in sediments. Our results provide valuable information for environmental pollution control and mitigation during harbor development and management.(c) 2022 Elsevier B.V. All rights reserved.

Automated summary

This study evaluated sediment metal pollution in Hsingda Harbor, a multi-functional harbor in southwestern Taiwan. The contamination level and ecological risks were determined using multiple sediment pollution indices based on total metal contents and their chemical partitioning fractions. The results identified fisheries-related activities and a nearby coal-fired power plant as the primary sources of potentially toxic metal pollution. The findings provide valuable information for environmental pollution control and mitigation during harbor development and management.