Some selected heavy metal concentrations in water, sediment, and oysters in the Er-Ren estuary, Taiwan: chemical fractions and the implications for biomonitoring

Abstract

Studies of heavy metal contamination and ecological risk in estuaries are an important emerging area of environmental science. However, there have been few detailed studies of heavy metal contamination that concern the spatial variation of heavy metal levels in water, sediment, and oyster tissue. Because of the effective uptake of heavy metals, cultured oysters are a cheap and effective subject for study. This study, conducts an experiment in the Er-Ren river to examine the biological uptake of heavy metals in farmed, cultured oysters. The distribution of copper, zinc, lead, cadmium, and arsenic concentrations in water, sediment, and oysters from the Er-Ren river is also evaluated. By sequential extraction of the sediments, the following order of mobilities is found for heavy metals Pb > Cd > As > Zn > Cu. The highest percentages of heavy metals are found in the residual phase. The mean uptake rates for young oysters are 7.24 mg kg(-1) day(-1) for Cu and 94.52 mg kg(-1) day(-1) for Zn, but that for adult oyster is 10.79 mg kg(-1) day(-1) for Cu and 137.24 mg kg(-1) day(-1) for Zn. With good policies and management, the establishment of cultured oyster frames in these contaminated tributaries and near shore environments is a potential method for removing Cu and Zn and protecting the coast.

Continental-scale spatial distribution, sources, and health risks of heavy metals in seafood: challenge for the water-food-energy nexus sustainability in coastal regions?

“…Coastal regions are undergoing various issues including extraordinarily rapid development of marine resource exploitation, sharp increase in populations, and the extensive impact of anthropogenic activities (Backer et al 2019;Lu et al 2018;Lu et al 2019) industry and oceanographic engineering in the coastal regions have been damaging the offshore ecosystem due to discharge of industrial effluent and domestic sewage (Bertocci et al 2019;Lu et al 2020;Zhang et al 2020). Heavy metals, stable in the aquatic environments, can be assimilated and accumulated in organisms to cause potential hazard so as to attract global attention (Chen et al 2014;Huang et al 2018). Heavy metals have been frequently detected in various regular food and seafood (Copat et al 2013;Liao and Yang 2020;Rai et al 2019;Varol et al 2017).…”

“…The coastal environments have been polluted by various pollutants with high ecological-health risks due to the rapid industrialization and urbanization in coastal regions. The risks of consuming seafood obtained from a bay or a coastal city in terms of heavy metals were evaluated (Chen et al 2014;Fakhri et al 2018;Li and Gao 2014). However, no comprehensive information is available to answer whether it is safe to frequently consume seafood in the coastal regions at national or continental scale.…”

Sediment Properties and Benthic Fauna Associated with Stock Enhancement and Farming of Marine Bivalve Populations in Xiangshan Bay, China

“…Heavy metals are highly persistent and toxic to humans due to the potential for bioaccumulation throughout the food chain. Many molluscs have been employed as contamination indicators due to their ability to accumulate heavy metals [61,62]. Te common mussel Mytilus edulis has been found to have heavy metal concentrations from 10 3 to 10 6 times higher than the concentrations in the surrounding water [63].…”

Bioaccumulation of Trace Metals in Oyster (Crassostrea gasar) from the Milliardaires Bay (Ebrié Lagoon, Côte d’Ivoire)

“…Marine organisms are able to accumulate trace metals and finally impose health hazard to consumers 2 . Thus, due to the potentials for human exposure, trace metal concentrations in aquatic organism has been identified as a concern in coastal environment [3][4][5] . Zinc, copper, and iron are essential in trace amounts for biological functioning of organisms.…”