Spatial variation and subcellular binding of metals in oysters from a large estuary in China.
TL;DR: Investigation of the spatial variation of metal pollution as well as their subcellular handling in the oyster Crassostrea hongkongensis found that there were different sources of metals in the estuary associated with industrial activity.
About: This article is published in Marine Pollution Bulletin.The article was published on 2013-05-15. It has received 51 citations till now. The article focuses on the topics: Oyster.
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TL;DR: It is elucidated that marine oysters had high ability to accumulate, biotransform, and detoxify inorganic As.
71 citations
TL;DR: The results showed that the seasonal patterns of metal concentrations in oysters were largely controlled by the biological process, while the variation as well as the concentration were dependent on the contamination levels and bioaccumulation ability.
66 citations
TL;DR: The complexity of life history and metal chemistry of oysters coupled with emerging pollution and application of modern techniques represents an important and exciting research area in modern ecotoxicology.
Abstract: Oysters are important benthic bivalves in coastal and estuarine environments. They are widely farmed due to their rapid growth and taste; they are also widely applied in environmental monitoring of coastal pollution due to their accumulation of contaminants. Most importantly, oysters are among the few marine organisms that are considered to be hyper-accumulators of many toxic metals, such as cadmium, copper and zinc. As such, there is a tremendous call to study the interactions between metals and oysters, especially due to the increasing metal pollution in many coastal and estuarine waters. Over the past decades, many studies have focused on metal accumulation in oysters as well as the ecotoxicological effects of metals on oysters. In this review, we summarize the recent progress in our understanding of the molecular and cellular mechanisms of metal accumulation, sequestration and toxicity in oysters. Applications of modern technologies such as omics and nanoscale imaging have added significantly to our knowledge of metal biology in oysters. Variations between different metals also demonstrate the diversity of the interactions between oysters and metals. Despite this recent progress, however, there is a need for further study of the molecular mechanisms of metal uptake and toxicity as well as the joint effects of metal mixtures on oyster populations. Oysters have higher numbers of stress responsive genes than most animals, which may have been induced by gene duplication during the evolution of their intertidal environmental adaptations. The divergent expression of stress responsive genes may explain the different tolerances for metals among different species. These fundamental studies may eventually provide promising solutions for reducing toxic metal concentrations in oysters for safe consumption by humans. To conclude, the complexity of life history and metal chemistry of oysters coupled with emerging pollution and application of modern techniques represents an important and exciting research area in modern ecotoxicology.
55 citations
TL;DR: The complexity of biomarkers responses under field condition is demonstrated, therefore the time changes of biomarker responses to metals need to be considered in evaluating the biological impacts of metal pollution on estuarine organisms.
44 citations
Cites background from "Spatial variation and subcellular b..."
...After exposure, the Cu concentrations in tissues increased by up to 88–121 folds, and the Cu and Zn levels in oysters from Station 2 were much higher than most previously reported concentrations in ‘blue’ or ‘green’ colored oysters (Han and Hung, 1990; Wang et al., 2011; Yu et al., 2013; Luo et al., 2014; Weng and Wang, 2014a)....
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...In recent years, similar ‘colored’ oysterswere found in some Southern Chinese estuaries and aroused considerable public concerns on metal pollution in these areas (Wang et al., 2011, 2014; Liu and Wang, 2012; Yu et al., 2013;Weng andWang, 2014a)....
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...…in tissues increased by up to 88–121 folds, and the Cu and Zn levels in oysters from Station 2 were much higher than most previously reported concentrations in ‘blue’ or ‘green’ colored oysters (Han and Hung, 1990; Wang et al., 2011; Yu et al., 2013; Luo et al., 2014; Weng and Wang, 2014a)....
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...They are able to survive in seriouslymetal polluted environments and accumulatemetals especially copper (Cu) and zinc (Zn) to extremely high levels (Wang et al., 2011; Yu et al., 2013)....
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01 Jan 2017
TL;DR: This chapter reviews the concentrations of several major metal contaminants in bivalve mollusks collected from different regions of the world and proposes some possibilities to reduce the metal contamination in these bivalves based on the current kinetic understanding of metal accumulation.
Abstract: This chapter reviews the concentrations of several major metal contaminants in bivalve mollusks collected from different regions of the world. Bivalve mollusks considered in this chapter include oysters, mussels, scallops, and clams, all of which are the major seafood products in the world. Oysters are the hyperaccumulators of copper and zinc, whereas scallops are the hyperaccumulator of cadmium. Reviews of the data suggested that Cd can be a potential safety problem for oysters and scallops. A few areas that displayed high metal contamination were identified. In addition, different seafood limits proposed by different countries are also reviewed and summarized. Finally, the chapter proposes some possibilities to reduce the metal contamination in these bivalve mollusks based on our current kinetic understanding of metal accumulation. It is critical to understand the species difference of metal bioaccumulation.
43 citations
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TL;DR: The significance of accumulated metal concentrations is discussed in terms of the biological significance, including the attempted recognition of a high or low concentration, and of the applied use of aquatic invertebrates in biomonitoring programmes assessing geographical and temporal variation in trace metal bioavailabilities in aquatic systems.
1,025 citations
TL;DR: Elevated levels of metal contamination along China's coastal environment can increase the risk of metal exposure to humans by seafood consumption, raising the alarm for more stringent control of discharge of metals into environment.
652 citations
Journal Article•
501 citations
TL;DR: It is hypothesized that progressive retention of metal as BDM (i.e. MRG) with age may lead to size dependency of metal concentrations often observed in some populations of M. balthica.
Abstract: Many aspects of metal accumulation in aquatic invertebrates (i.e. toxicity, tolerance and trophic transfer) can be understood by examining the subcellular partitioning of accumulated metal. In this paper, we use a compartmentalization approach to interpret the significance of metal, species and size dependence in the subcellular partitioning of Cd and Zn in the bivalves Macoma balthica and Potamocorbula amurensis. Of special interest is the compartmentalization of metal as metal- sensitive fractions (MSF) (i.e. organelles and heat-sensitive proteins, termed 'enzymes' hereafter) and biologically detoxified metal (BDM) (i.e. metallothioneins (MT) and metal-rich granules (MRG)). Clams from San Francisco Bay, CA, were exposed for 14 d to seawater (20 ‰ salinity) containing 3.5 µg l -1 Cd and 20.5 µg l -1 Zn, including 109 Cd and 65 Zn as radiotracers. Uptake was followed by 21 d of depuration. The subcellular partitioning of metal within clams was examined following exposure and loss. P. amurensis accumulated ~22 × more Cd and ~2 × more Zn than M. balthica. MT played an important role in the storage of Cd in P. amurensis, while organelles were the major site of Zn accu- mulation. In M. balthica, Cd and Zn partitioned similarly, although the pathway of detoxification was metal-specific (MRG for Cd; MRG and MT for Zn). Upon loss, M. balthica depurated ~40% of Cd with Zn being retained; P. amurensis retained Cd and depurated Zn (~40%). During efflux, Cd and Zn concentrations in the MSF compartment of both clams declined with metal either being lost from the animal or being transferred to the BDM compartment. Subcellular compartmentalization was also size-dependent, with the importance of BDM increasing with clam size; MSF decreased accordingly. We hypothesized that progressive retention of metal as BDM (i.e. MRG) with age may lead to size dependency of metal concentrations often observed in some populations of M. balthica.
490 citations
"Spatial variation and subcellular b..." refers background or result in this paper
...Consistent with these data, Wang et al. (2011) also reported that MTLP increased their importance in binding with Zn but decreased in binding with Cu as tissue concentrations of the metals increased....
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...It has been assumed that metals in the MTLP and MRG fractions can be considered as the biologically detoxified metals (BDMs), and metals in HSP and organelles can be considered as the metal-sensitive fraction (MSF) (Wallace and Luoma, 2003; Wallace et al., 2003)....
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TL;DR: The similar Pb isotopic signatures of the sediments offered strong evidence that the PRE was a major source of trace metals to the adjacent coastal area, and slightly lower Pb/Pb ratios in the coastal sediments may indicate other inputs of Pb in addition to the PRE sources, including the inputs from Hong Kong and other parts of the region.
465 citations
"Spatial variation and subcellular b..." refers background in this paper
...Cu containing herbicides) in the PRE region (Ip et al., 2004; Ip et al., 2007; Chen et al., 2012)....
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