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1.
Fu CT  Wu SC 《Marine pollution bulletin》2005,51(8-12):932-939
This study investigated the bioaccumulation of polychlorinated biphenyls (PCBs) toward mullet fish (Liza macrolepis) living in former PCB contaminated areas, the Ann-Ping harbour and the Er-Jen estuary, and fish farms located near the above two areas in 2003. The PCB body burdens of collected fish samples are proportional to the contamination level of their locations with the following rank order (greatest to least) from the Er-Jen estuary, the Ann-Ping harbour to the fish farms. Concentration of PCBs of the estuarine mullet has been approximately decreased to one-half of the peak concentration of the 1990s. Although the concentration of PCBs in farmed fish inhabiting near the two contaminated areas was greater than the average of those of fish from local fish markets in Taiwan, no particularly great contamination level was observed in their bodies. Using the less chlorinated PCB fraction (triCB + tetraCB)/total PCBs as the indicator of the origins of PCBs, fish near former contaminated areas had greater body burdens of the more chlorinated PCB congeners, while the farmed fish exhibited a PCB pattern more like that known to originate from air–water exchange with less chlorinated PCBs predominating. Although the PCB contamination has been stopped for a decade, the residual contaminants, supposedly existing in soil and sediments, still contribute to the body burden of fish residing in the estuary and the harbour.  相似文献   

2.
Patterns of bioaccumulation of polychlorinated biphenyls (PCBs) by chironomid larvae (Chironomus riparius Meigen) were studied under laboratory conditions. Larvae were maintained for 20 days, separately in two batches of natural bottom sediments sampled from Rybinsk Reservoir (Russia), each differing in PCB content (425.6 μg / kg or 24.8 μg / kg dry weight, respectively). The study revealed that chironomid larvae accumulated PCBs at levels comparable to the PCB content measured in sediments from each exposure. The bioaccumulation coefficient (1.11 and 1.59, respectively, as per dry weight for compared sediment batches) depended directly on the sum PCB content in sediments. At high sediment PCB content, the ratios of homologous groups of PCBs in larvae and sediment were identical and corresponded to the Aroclor 1254 congeners profile; at lower PCB content, pronounced differences were revealed. In larvae, the ratios of 3, 4, 5, and 6CB homologues were evenly distributed at levels of 20–34 %, while the 4CB homologues prevailed (47 %) in sediments. The content of the latter compounds in larvae was lower than in sediments, and higher for the other homologous groups. The study indicates selective bioaccumulation of various homologous groups of PCBs under conditions of low sediment PCB content.  相似文献   

3.
Carcinus maenas is an important and exploited natural resource in temperate estuaries, being consumed by local populations and also used as fish bait. Through bioaccumulation and bioamplification processes occurring in polluted estuarine ecosystems, this species may directly or indirectly represent a major pathway for Human contamination. No information is available on the overall lifespan bioaccumulation pattern of mercury for this species, which would be an invaluable tool for assessing the risks associated with C. maenas harvest in contaminated areas. Taking that in mind, the main objectives of this work were to clarify the lifespan bioaccumulation pattern of mercury for this species. A consistent lifespan accumulation pattern was found for this species, both for total and organic mercury, and coherent differences were found between genders, suggesting different physiological responses to contamination. From our results two scenarios emerge: (a) for low mercury contamination areas where the diet is the major pathway for metal uptake, with higher levels in muscle and hepatopancreas (twice as high as in gills) and higher organic mercury fractions (as high as 80-90% in muscle), crabs bioaccumulate with age and (b) on high contaminated areas, environmental exposure is predominant, with higher levels found in gills (reaching 0.8 mg kg(-1)), lower organic fractions and no mercury increment with age. Detoxification strategies, dietary differences and species mobility may account for these two accumulation patterns.  相似文献   

4.
The bioaccumulation of PCB and DDT compounds by mussels, Mytilus spp., from ambient seawater was determined by measuring concentrations of these chlorinated hydrocarbons in both mussels and seawater at four sites on the Mediterranean coast of France and two sites in California. Bioaccumulation factors were found to vary over an order of magnitude. Ratios of the concentrations of PCB in mussels, consisting predominantly of pentachloro-and hexachlorobiphenyls, to concentrations in ambient seawater ranged between 69 000 and 690 000; the corresponding ratios of concentrations of p,p′-DDE or p,p′-DDT ranged from 40 000 to 690 000. Although mussels appear to be appropriate and convenient indicator organisms of local chlorinated hydrocarbon contamination levels, the factors contributing to this variance must be determined before mussels are widely used in global monitoring programmes.  相似文献   

5.
Concentrations of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), and polybrominated diphenyl ethers (PBDEs) were measured in 32 species inhabiting the Yellow Sea to assess their bioaccumulation potentials. The concentrations in these samples were lower than those reported for other countries or locations. Relatively high levels of BDE 209 in biota suggest an ongoing source of deca-BDE technical mixing within the Yellow Sea. The accumulation profiles of PCBs were uniform between species, but the concentrations of OCPs and PBDEs varied widely. Pelagic and benthic food-chain components were separated by their δ13C values. Significant positive correlations between δ15N and PCB 153, PCB 138, p,p′-DDE, oxy-chlordane, and trans-nonachlordane were found only for pelagic consumers, indicating that the pelagic food chain is an important bioaccumulation pathway for selected PCB and OCP compounds. The other compounds did not show any biomagnification through benthic and pelagic food chains, suggesting the lower bioaccumulation potentials of these contaminants.  相似文献   

6.
In the present work, we built a mathematical model of polychlorinated biphenyl (PCB) bioaccumulation in Perna viridis, namely, a one-compartment model with a time dependent incorporation rate R (μg g−1 lipid per ppb water per day), with positive substrate cooperativity as the underlying physical mechanism. The temporal change of the PCB concentration Q (μg g−1 lipid) in the soft tissues of the mussel depends on the competition of the input rate RW and the output rate kQ, where W is the concentration of PCB in water (ppb water) and k is the elimination rate (per day). From our experimental data, k=0.181±0.017 d−1. The critical concentration in water Wc for positive substrate cooperativity was found to be 2.4 ppb. Below Wc, R is a constant. For a water concentration of 0.5 ppb Aroclor 1254, R=24.0±2.4 μg g−1 lipid ppb−1 d−1. Above Wc, positive substrate cooperativity comes into effect and R becomes a function of time and dependent on the concentration Q in a form R=γQ/(Q+δ). This is the case for a water concentration of 5 ppb Aroclor 1254, where γ=15.1 μg g−1 lipid ppb−1 d1 and δ≈200 μg g−1 lipid. From this model, the uptake is exponentially increasing when the PCB concentration in the mussel is small compared to 200 μg g−1 lipid, and hyperbolically increasing when the concentration is large compared to 200 μg g−1 lipid, which are consistent with the experimental data. The model is useful for understanding the true processes taking place during the bioaccumulation and for risk assessment with higher confidence. Future experimental data which challenge the present model are anticipated and in fact desirable for improvement and perfection of the model.  相似文献   

7.
Ye R  Zou E 《Marine pollution bulletin》2008,57(6-12):307-312
Since increased ventilation is known to be a common strategy used by aquatic animals to cope with hypoxia, we tested in present study the hypothesis that hypoxia can promote the bioaccumulation of naphthalene, a representative polycyclic aromatic hydrocarbon (PAH), in Penaeus aztecus, a penaeid shrimp subject to hypoxia and PAH contamination in the northern Gulf of Mexico. For each of the two naphthalene concentrations, five groups of shrimps were, respectively, subjected to five different conditions, namely, clean seawater under normoxia, seawater containing acetone under normoxia and hypoxia, and seawater containing 10 or 250 microg/L naphthalene under normoxia and hypoxia. Our results suggest that hypoxia does not significantly alter naphthalene bioaccumulation in either the gills or the hepatopancreas of P. aztecus. The absence of a promoting effect of hypoxia on naphthalene bioaccumulation is attributed to the increased disposition of naphthalene when the shrimps are subjected to hypoxia.  相似文献   

8.
To investigate the influence of mangrove reforestation on the accumulation of PCBs, the concentrations and homologue patterns of polychlorinated biphenyls in surface sediments from different mangrove forests and their adjacent mud flats in Guangdong Province were determined. The total PCB concentrations in the sediments ranged from 3.03 to 46.62 ng g?1 (dry weight). Differences in the accumulation and distribution of PCBs were found between the mangrove sites and the mud flats. Furthermore, the natural forests and restored mangrove forests of native species showed slight PCB contamination, whereas the exotic species Sonneratia apetala exacerbated the PCB pollution at certain sites. It was suggested that the native mangrove species Kandelia candel and Aegiceras corniculatum could represent good choices for the phytoremediation of PCB contamination.  相似文献   

9.
The impact of seasonal fluctuations in forcing factors such as atmospheric concentration, temperature, and biological productivity on the concentration of polychlorinated biphenyls (PCBs) in the surface water of the southern part of the Baltic Sea was investigated. Water samples were collected on eight cruises over 2 years. A clear seasonal variability in dissolved PCB concentrations was observed with higher levels in summer than in winter and spring. This was attributed to changes in atmospheric concentrations and water temperature, based on measurements showing the PCB levels in the atmosphere and surface water to be close to a partitioning equilibrium. Concentrations in the suspended particulate material (SPM) fraction were also variable, and when the quotient of the organic carbon normalised concentration in SPM and the dissolved concentration was calculated (i.e., the bioaccumulation factor (BAF)), a seasonal pattern was observed which was consistent with kinetic limitations on partitioning into particles caused by plankton growth. However, seasonal variability in the partitioning properties of the SPM may also contribute to this variability.  相似文献   

10.
PCB (polychlorinated biphenyls) contamination and its relationship to SPM (suspended particulate material) have been studied in the Seine Estuary, which is heavily polluted by these persistent and hydrophobic man-made chemicals. Two sampling cruises have been performed during different freshwater discharge conditions. PCB and SPM concentrations, as well as grain-size distributions in the particulate material have been determined. Water samples have been collected at fixed positions during a tidal cycle, and along transects within the estuary.PCB concentrations vary from 2 ng 1−1 in the marine zone to 250 ng 1−1 within the estuary, and reach 1.3 × 103 ng 1−1 in the turbidity maximum zone. During a tidal cycle, low PCB concentrations are observed at high water, and are in the same range in February as in July. High PCB contamination is observed at low water, but PCB concentrations are about five times higher in February. SPM and PCB variations are well correlated in both periods of observations. Higher PCB contamination during February is explained by higher SPM inputs, mainly due to particles of riverine origin. The transport of PCB within the estuary depends on the quantity and the grainsize composition of suspended material, which varies according to freshwater discharge and tidal amplitude.  相似文献   

11.
The Hudson River estuary has enormous spatial variation in polychlorinated biphenyl (PCB) contamination due in large part to historical point source discharges above Troy Dam. The Delaware River estuary has accumulated significant levels of PCBs through decades of industrial, municipal, and non-point source inputs. The overall goal of this research was to use existing data sets to compare and contrast the patterns of accumulated PCB congeners in sub-populations of American eels and striped bass inhabiting these two estuaries and surrounding coastal waters. Using principal component analysis and analysis of covariance (ANCOVA), inter- and intra-estuarine differences in accumulated congeneric patterns were denoted for both species. Results from our study support the idea that migratory behaviors of striped bass hamper the use of accumulated congener-specific PCB patterns in providing information on localized contamination, although major regional differences were seen between upriver Hudson River fish, downriver Hudson River fish and fish from other areas within this study. This study provides additional evidence for the use of the American eel as a biomonitoring tool, since its limited home range provides finer resolution of regional contamination.  相似文献   

12.
Since increased ventilation is known to be a common strategy used by aquatic animals to cope with hypoxia, we tested in present study the hypothesis that hypoxia can promote the bioaccumulation of naphthalene, a representative polycyclic aromatic hydrocarbon (PAH), in Penaeus aztecus, a penaeid shrimp subject to hypoxia and PAH contamination in the northern Gulf of Mexico. For each of the two naphthalene concentrations, five groups of shrimps were, respectively, subjected to five different conditions, namely, clean seawater under normoxia, seawater containing acetone under normoxia and hypoxia, and seawater containing 10 or 250 μg/L naphthalene under normoxia and hypoxia. Our results suggest that hypoxia does not significantly alter naphthalene bioaccumulation in either the gills or the hepatopancreas of P. aztecus. The absence of a promoting effect of hypoxia on naphthalene bioaccumulation is attributed to the increased disposition of naphthalene when the shrimps are subjected to hypoxia.  相似文献   

13.
《Marine pollution bulletin》2009,58(6-12):307-312
Since increased ventilation is known to be a common strategy used by aquatic animals to cope with hypoxia, we tested in present study the hypothesis that hypoxia can promote the bioaccumulation of naphthalene, a representative polycyclic aromatic hydrocarbon (PAH), in Penaeus aztecus, a penaeid shrimp subject to hypoxia and PAH contamination in the northern Gulf of Mexico. For each of the two naphthalene concentrations, five groups of shrimps were, respectively, subjected to five different conditions, namely, clean seawater under normoxia, seawater containing acetone under normoxia and hypoxia, and seawater containing 10 or 250 μg/L naphthalene under normoxia and hypoxia. Our results suggest that hypoxia does not significantly alter naphthalene bioaccumulation in either the gills or the hepatopancreas of P. aztecus. The absence of a promoting effect of hypoxia on naphthalene bioaccumulation is attributed to the increased disposition of naphthalene when the shrimps are subjected to hypoxia.  相似文献   

14.
In the last few decades, several integrated methods for marine sediment quality evaluation have been developed and applied to many coastal sites. This paper describes the development of a general integrated method based on the determination of organic and inorganic sediment contamination, lethal and sublethal toxicity assessments, in situ benthonic community structure alteration and bioaccumulation of contaminants. The proposed method was applied to sediments from Southern Spain's Atlantic coast where six rivers (Guadiana, Carreras, Piedras, Tinto, Odiel and Guadalquivir) drain pollutants from various anthropogenic sources. A series of experiments was conducted to determine the characteristics of the sediments: granulometry, organic matter content, etc. (1); metal contamination of sediments and Chamelea gallina (bivalves widely distributed in the area studied) (2); lethal and sublethal toxicity by a series of biological tests (3); and macrofauna distribution at the 16 stations included in the study (4). Ratio-to-reference values (RTR) calculated for each parameter were used to determine the organic and inorganic contamination indices, the lethal and sublethal toxicity indices, the index of bioavailability of metals in the organisms analyzed and the macrobenthic alteration index. The data were plotted on six-axis plots to describe better the relations between the physical, chemical and biological properties studied. A general integrated sediment quality index (ISQI) was determined and used as an indicator of pollution-induced degradation. The ISQI values summarize the main characteristics of the environmental situation at each sampling point and can be used for purposes of comparison.  相似文献   

15.
《Marine pollution bulletin》2013,77(1-2):170-177
The main objective of this paper was to evaluate the impact of mercury on the zooplankton communities’ structure and functioning and their bioaccumulation patterns along a contamination gradient in a temperate coastal lagoon. Our results demonstrated that total abundance was not negatively affected by Hg contamination, since the most contaminated areas presented the highest values, being the copepod Acartia tonsa the dominant species, which means that it is a very well adapted and tolerant species to mercury. Nevertheless, negative effects were observed in terms of species diversity, since the most contaminated areas presented the lowest values of species richness, evenness and heterogeneity. Moreover, the spatial mercury gradient was reflected on the bioaccumulation patterns of the zooplankton communities. This reinforces the idea that zooplankton can be considered as an important vehicle of mercury transfer through the food pelagic web since it constitutes a primordial food resource for several commercial fish species.  相似文献   

16.
PCBs were analysed in surficial sediments and selected sediment cores collected between 2002 and 2008 in Central Vietnam coastal lagoons. The aim was to determine contamination levels and trends, and to evaluate the effects of anthropogenic pressures and natural events. Samples were mostly fine-grained with low total PCB concentrations (0.367-44.7 μg kg−1). Atmospheric transport and post depositional processes modify to some degree the fingerprint of PCB inputs to the environment favouring the predominance of 3, 4 and 5 chlorinated congeners. The similarity of congener distributions in contemporary surficial samples also suggests the presence of a unique source over the entire study area, probably connected to mobilisation and long range transports from land-based stocks. The removal of consistent sediment layers is hypothesised based on repeated samplings of the same area. Natural meteorological events (such as typhoons) are suspected to be responsible for these sediment losses.  相似文献   

17.
In the present work, we built a mathematical model of polychlorinated biphenyl (PCB) bioaccumulation in Perna viridis, namely, a one-compartment model with a time dependent incorporation rate R (μg g−1 lipid per ppb water per day), with positive substrate cooperativity as the underlying physical mechanism. The temporal change of the PCB concentration Q (μg g−1 lipid) in the soft tissues of the mussel depends on the competition of the input rate RW and the output rate kQ, where W is the concentration of PCB in water (ppb water) and k is the elimination rate (per day). From our experimental data, k=0.181±0.017 d−1. The critical concentration in water Wc for positive substrate cooperativity was found to be 2.4 ppb. Below Wc, R is a constant. For a water concentration of 0.5 ppb Aroclor 1254, R=24.0±2.4 μg g−1 lipid ppb−1 d−1. Above Wc, positive substrate cooperativity comes into effect and R becomes a function of time and dependent on the concentration Q in a form R=γQ/(Q+δ). This is the case for a water concentration of 5 ppb Aroclor 1254, where γ=15.1 μg g−1 lipid ppb−1 d1 and δ≈200 μg g−1 lipid. From this model, the uptake is exponentially increasing when the PCB concentration in the mussel is small compared to 200 μg g−1 lipid, and hyperbolically increasing when the concentration is large compared to 200 μg g−1 lipid, which are consistent with the experimental data. The model is useful for understanding the true processes taking place during the bioaccumulation and for risk assessment with higher confidence. Future experimental data which challenge the present model are anticipated and in fact desirable for improvement and perfection of the model.  相似文献   

18.
Management of coastal ecosystems necessitates the evaluation of pollutant loading based on adequate source discrimination. Monitoring of sediments and fish on the shelf off San Diego has shown that some areas on the shelf are contaminated with polychlorinated biphenyls (PCBs). Here, we present an analysis of PCB contamination in fish on the shelf off San Diego designed to discriminate possible sources. The analysis was complicated by the variability of species available for analysis across the shelf, variable affinities of PCBs among species, and non-detects in the data. We utilized survival regression analysis to account for these complications. We also examined spatial patterns of PCBs in bay and offshore sediments and reviewed more than 20 years of influent and effluent data for local wastewater treatment facilities. We conclude that most PCB contamination in shelf sediments and fish is due to the ongoing practice of dumping contaminated sediments dredged from San Diego Bay.  相似文献   

19.
This project was carried out to assess the levels and spatial distribution of organochlorine compounds in the coastal marine environment, using mussels as bioindicators to evaluate the coastal water quality. Levels of polychlorobiphenils (PCB), chlorinated pesticides (DDT isomers, HCH isomers, Aldrin, Dieldrin, alfa-Endosulfan, Hexachlorobenzene, Pentachlorobenzene) and polybrominated diphenyl ethers (PBDEs) were determined in tissues from mussels (Mytilus galloprovincialis) collected along the Apulia Region coasts (Mediterranean Sea). Results indicate that contamination by organochlorine compounds is higher in mussels sampled in the Ionian Sea than in those from the Adriatic Sea, with PCB levels up to seven times higher in mussels from Ionian than from the Adriatic Sea. Although PCB levels were above the maximum values indicated by both European Community (EC) and National regulation in several sample sites, the PCB concentrations were particularly high in some stations, suggesting that these locations require a much specific attention. Conversely, results on the mussel contamination by PBDEs highlight their ubiquitous environmental distribution, and underline the need to establish the maximum level for these compounds in foodstuff, according to European Regulations.  相似文献   

20.
The distribution and bioaccumulation features of PCBs, DDTs, and HCHs were investigated in the sediments and Manila clams collected from along the Mid-Western coast of Korea. The measured concentrations of ΣPCBs, ΣDDTs and ΣHCHs were 1.08–3.5, 0.12–0.35 and 0.090–0.30 ng g−1 dw in sediment, and 33–390, 7.4–46 and 6.3–27 ng g−1 lipid in Manila clam, respectively. Their levels were found to be relatively lower than those of other contaminated areas and the consumption of Manila clam from these areas seems to be safe for human health according to calculated lifetime cancer risk and hazard indices. The ΣPCBs and ΣDDTs concentrations in sediments showed a significant relationship to those in clams. The significant correlation was observed between BSAF in clams and Kow for each PCB congeners and DDT metabolites. These findings support that the PCBs and DDTs levels, which are highly hydrophobic chemicals, in clam reflect the sediment pollution through bioaccumulation.  相似文献   

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