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1.
Semi-batch seawater experiments were conducted to follow the uptake and release of selected PAHs (anthracene, fluorathene, pyrene and B[a]P) and organochlorine pesticides (α-HCH, aldrin, dieldrin, p,p′-DDT) in semi-permeable membrane devices (SPMDs) and green-lipped mussels (Perna viridis). Mathematical models were applied to describe the uptake and elimination curves of the contaminants for SPMDs, and kinetic parameters, such as uptake rate constants, and equilibrium triolein/water partitioning coefficients were calculated. SPMD data showed a good fit to estimate rate constant and partition coefficient equations, but only those contaminants which partitioned mainly in the dissolved phase (α-HCH and dieldrin) were well explained for mussels. Poor conformity of the other contaminants indicated mussels uptake by routes other than diffusion, such as ingestion of algae. An apparent equilibrium state was only noted for α-HCH in mussels. Aldrin was not detected in mussels in the first few days of exposure, indicating potential metabolism of this compound. B[a]P was not detected in the triolein of SPMDs, which suggests that the membrane may act as a reservoir. Loss of spiked B[a]P from the triolein was evident in a depuration experiment, which may indicate transfer to the membrane. Rate constants for mussels were higher than those for SPMDs, but the reverse was true for partition coefficients. Overall, mussels and SPMDs had similar uptake rates for all compounds in this study, excluding p,p′-DDT and dieldrin. Contaminant elimination took place more rapidly in mussels, implying that SPMDs are better candidates for detecting episodic discharge of organic contaminants.  相似文献   

2.
The outer layers of layflat, low density polyethylene plastic tubing (the principal component of semi-permeable membrane devices, SPMDs) were biofouled at a clean site in Hong Kong coastal waters for periods of 1–4 weeks. Following pre-fouling, triolein was added to the SPMDs and, along with control (unfouled) devices, they were exposed to a range of organochlorine pesticides (-HCH, aldrin, p,p′-DDT) and PAHs (anthracene, fluoranthene and benzo(a)pyrene) under laboratory conditions. Results showed that the uptake of contaminants by SPMDs was severely reduced by as much as 50% under fouling conditions in comparison to unfouled controls. The ultimate utility of SPMDs as passive monitors is thus reduced, although alternative measures, such as the use of permeability reference compounds may compensate, and allow for realistic evaluations of dissolved environmental concentrations in aquatic environments. However, due to the complexities involved in such procedures––especially as they need to be conducted on a case-by-case basis––the utility of SPMDs appears to be limited for estimates of bioavailability unless necessary calibrations are undertaken within each environment that the sampler is used.  相似文献   

3.
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   

4.
Results of mercury and organochlorine analyses in pooled muscle and blubber samples representing in all 417 long-finned pilot whales (Globicephala melas) sampled in 1997 in the Faroe Islands are presented. The 28 pooled muscle samples from (in all) 9 pods were analysed for total mercury and the same number of pooled blubber samples were analysed for PCB (IUPAC CBs no. 28, 52, 99, 101, 105, 118, 128, 138, 153, 170, 180, 183 and 187), p,p′-DDT and metabolites and o,p′-DDT and metabolites, cis () and trans (γ)-chlordane, cis- and trans-nonachlor, oxychlordane, mirex, hexachlorobenzene, β-HCH and toxaphene (Parlars no. 26 (T2), 32, 50 (T12), 62 (T20) and 69.  相似文献   

5.
PCBs, p,p′-DDT, p,p′-DDE and lindane (γ-hexachlorocyclohexane) were monitored in the lower atmosphere of Ross Island, in Antarctica for 2 yr. Geometrical means were 15.2 pg m−3 for PCBs, 2.0 pg m−3 for p,p′-DDT, 1.0 pg m−3 for p,p′-DDE and 25.8 pg m−3 for lindane. Atmospheric levels of lindane were positively correlated with temperature, and a significant difference was found between spring-summer and summer-winter concentrations. No season related differences were found for the other chlorinated hydrocarbons, possibly owing to their lower vapour pressure and the cold climate. Periods with increased atmospheric levels of PCBs and DDT compounds were recorded. Lindane, p,p′-DDE and PCBs were present in fish and zooplankton sampled close to Ross Island. Pollutant levels in the zooplankton (on an extractable fat basis) were highest during the Antarctic spring and autumn and were inversely correlated to their fat content.  相似文献   

6.
A distinct lack of historical and current data on the status of organic pollutant contaminants within the South African marine environment is evident. This has highlighted the need for more current organic pollutant assessments. Reference mussels and SPMDs were transplanted at five South African harbour sites to assess organic bioaccumulation in brown mussels (Perna perna) and semi-permeable membrane devices (SPMDs). Spatial patterns of PAH and PCB contaminants were determined by GC-MS and GC-ECD after appropriate sample preparation. Significant (p<0.05) spatial differences were observed between the sites. Results indicate no correlations between the passive device and the transplanted mussels; however the SPMDs provided complementary information on the presence of dioxin-like PCBs within the environment not detected by the mussel. The results indicate that information provided by both the mussels and SPMDs allow for a more in depth scrutiny of environmental conditions as a result of anthropogenic influence.  相似文献   

7.
The lysosomal membrane destabilization and the metallothionein content in the digestive gland cells of mussels (Mytilus galloprovincialis Lam.), collected along the east coast of the North Adriatic (Istrian and Kvarnerine coast, Croatia), were examined over a period of four years (1996–1999). The lysosomal membrane stability, as a biomarker of general stress, showed that the membrane labilization period in mussels from polluted, urban- and industrial-related areas was significantly decreased (p<0.05) when compared to mussels from control, clean sea water sites. In the harbour of Rijeka, the most contaminated site, the lysosomal membrane stability was reduced by more than 70% compared to the control. This method also proved to be a useful biomarker for detection of additional stress caused by short-term hypoxia that occurred once during this study inside the polluted and periodically quite eutrophic Pula Harbour. The concentration of metallothioneins in the mussel digestive gland, as a specific biomarker of exposure to heavy metals, did not reveal significant differences (p<0.05) between sites covered by this study.  相似文献   

8.
Sediment and biota samples were collected from Msimbazi and Kizinga rivers and from the coastal marine environment of Dar es Salaam during both dry and wet seasons. The samples were analyzed for various organochlorine pesticide residues using GC-ECD and GC-MS. Dieldrin, p,p′-DDT, p,p′-DDE, p,p′-DDD, o,p′-DDT and γ-HCH were detected at significantly greater concentrations above the method detection limits. Recoveries of pesticide residues ranged 86.5–120% in sediments and 62–102% in biota. The average concentrations of total DDT in sediments for the two seasons were almost the same. Biota samples showed significant difference in levels of residues depending on mode of feeding and age of analyzed biota. p,p′-DDT to total DDT ratios in all matrices indicated recent use of DDT. The levels of residues in sediments suggest possible adverse effects to humans consuming biota that are directly exposed to the sediments. This effect, which is associated with bio-concentration of residues in the tissues of edible aquatic biota, should not affect wildlife. In spite of concern on the adverse effect to humans posed by pesticide residues in sediments, edible biota from the examined water bodies were found to be safe for human consumption.  相似文献   

9.
The contamination of organochlorine pesticides (OCPs) in sediments from the Wu-Shi River estuary was investigated to evaluate the pollution potentials and distribution of OCPs in central Taiwan. A total of 19 sediment samples were collected at five sampling stations along the River estuary. The concentrations of OCPs were in the range of 0.99–14.5 ng/g-dry weight (dw) for ΣHCH (-, β-, γ-, δ-HCH), 0.46–13.4 ng/g-dw for Σcyclodiene and 0.53–11.4 ng/g-dw for ΣDDT (p,p′-DDD, p,p′-DDE, p,p′-DDT). The mean concentrations of ΣHCH, Σcyclodiene and ΣDDT were 3.79, 4.87 and 2.51 ng/g-dw, respectively. The total concentrations of OCPs correspond to 1.73–71.9 μg/g-OC when normalized to TOC contents. Among the organochlorine pesticides, endosulfan sulfate, β-HCH, and p,p′-DDD were the most dominant compounds in the sediments with the average concentrations of 1.97, 3.43 and 2.08 ng/g, respectively. Also, different contamination patterns among sampling seasons were observed. The measured concentrations of OCPs collected in spring were higher than those in autumn and winter. A linear relationship between sediment characteristics and OCP residues was also demonstrated. The results obtained in this study show that there still exist a variety of organochlorine pesticide residues in the sediments from the near shore of central Taiwan.  相似文献   

10.
The influence of intertidal crab beds on the concentrations of organochlorine (OC) pesticides in sediment was studied in two different coastal environments in Argentina. Samples of male burrowing crabs (Chasmagnathus granulatus) were collected for this study. Our field data showed lower bioaccumulation of OC pesticides in crabs from sediments with a higher total organic carbon (TOC) and higher clay content. Thus, concentrations in crabs depend on the physico-chemical characteristics of the sediment where they live more than on the OC pesticide concentrations in the environment. The distribution patterns in sediment from inside and outside crab burrows were similar for both coastal areas being HCHs  γ-chlordane > p,p′-DDE for San Antonio Bay (SAO), and HCHs > p,p′-DDE  γ-chlordane for Mar Chiquita (MCh) coastal lagoon. OC pesticide concentrations in sediment were significantly lower inside than outside crab burrows, irrespective of the sediment physico-chemical characteristics due to the bioturbation activity of C. granulatus.  相似文献   

11.
Polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCs) are generally present in the marine environment in complex mixtures. The ecotoxicological nature of contaminant interactions, however, is poorly understood, with most scientific observations derived from single contaminant exposure experiments. The objective of this experiment was to examine dose-response relationships between antioxidant parameters and body contaminant levels in mussels exposed to different exposure regimes under laboratory conditions. Accordingly, the green-lipped mussel, Perna viridis, was challenged with a mixture of PAHs (anthracene, fluoranthene, pyrene, benzo[a]pyrene) and OC pesticides (α-HCH, aldrin, dieldrin, p,p′-DDT) over a 4 week period. Contaminants were delivered under four different dosing regimes, with all treatments receiving the same total contaminant load by the end of the exposure period. Antioxidant biomarkers were measured after 1, 2, 3 and 4 weeks, including glutathione (GSH), gluathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and lipid peroxidase (LPO). GST and CAT were induced in hepatic tissues in most of the exposure regimes, with the majority of significant induction occurring in a constant exposure regime and a two-step alternate exposure regime. Significant differences among exposure regimes were detected in the body burden of contaminants after 28 days. Hepatic CAT and GSH are proposed as potentially useful biomarkers as they showed good correlation with target contaminants and were not readily affected by different dosing patterns.  相似文献   

12.
Side-by-side comparisons of polycyclic aromatic hydrocarbon (PAH) concentrations in resident blue mussels (Mytilus trossulus) and in semi-permeable membrane devices (SPMDs) were made at four sites in Prince William Sound, Alaska. SPMDs were deployed for approximately 30 days on the surface of the beach sediment at three tidal elevations on each shore and in 0.5 m deep open pits in the middle intertidal zone. Total PAH (TPAH) concentrations in mussels and in SPMDs were correlated, but the PAH compositions were different. The lower molecular weight PAH were relatively more abundant in the SPMDs than in the mussels at oiled and HA sites. TPAH concentrations in SPMDs deployed in pits and mussels collected adjacent to those pits at oiled sites were higher than in SPMDs and mussels from non-pitted SPMD locations approximately 3-15 m from the pits. Pitting released buried oil making its PAH bioavailable. SPMDs deployed in the supratidal zone (+4.0 m tidal elevation) were exposed to atmospheric contaminants for a large fraction of the deployment time and accumulated primarily pyrogenic (combustion-sourced) PAH from the atmosphere. The SPMD strips supplied by the manufacturer contained significant amounts (approximately 125 ng/strip) of primarily alkylated 2-3 ring PAH. These blank levels make SPMDs unsuitable for shoreline assessments when environmental PAH concentrations are low. Consequently, where available, mussels are recommended for use in assessments of the bioavailability of buried oil residues sequestered in intertidal sediments following an oil spill. Mussels are the preferred monitoring tool when the assessments involve food-chain effects. At locations where the absence of mussels necessitates the use of SPMDs or other passive sampling devices, their limitations need to be carefully considered in the interpretation of results.  相似文献   

13.
Green-lipped mussels, Perna viridis, and Manila clams, Ruditapes philippinarum were sourced from “clean” sites in the Hong Kong region, depurated in a laboratory using uncontaminated filtered seawater for 8 days, and transplanted to a suspected gradient of chemically polluted sites in Hong Kong. After 14- and 28-days of field exposure, several antioxidant parameters including glutathione S transferase (GST), catalase (CAT), glutathione peroxidase (GPx), and glutathione (GSH) were quantified in gill and hepatopancreas tissues. Whole body tissue concentrations of polycyclic aromatic hydrocarbons (PAHs), petroleum hydrocarbons (PHCs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCs) were determined in pooled site samples. Chemical analyses indicated that: (a) clams had higher levels of PAHs, PHCs, DDTs and PCBs, whereas mussels had higher hexachlorocyclohexane (HCHs) and there was no difference between species for dieldrin and remaining OCs; (b) Kat O should not be continued as a “clean” reference site for Hong Kong, because of the levels of contaminants measured and (c) PAH concentrations in the current survey were similar to those previously measured. Toxicological conclusions were: (a) antioxidant responses were different between species; (b) CAT and GST have highest utility in clams for field use in Hong Kong, whereas CAT in both gill and hepatopancreas tissue showed most potential in mussels; (c) significant induction of antioxidant responses over day 0 (excluding GPx in both tissues, and GST in mussel hepatic tissue); (d) groups of contaminants do not consistently induce antioxidant responses and (e) organochlorines and PCBs correlated significantly with CAT and GST in clam hepatopancreas and with CAT in mussel gill and hepatic tissue. Multivariate statistical techniques indicated little relationship between the site patterns for antioxidant responses and the contaminant gradients identified in body burden analysis.  相似文献   

14.
This study was undertaken to examine the use of imposex in the tropical neogastropod whelk Morula granulata as bioindicator of tributyltin (TBT) contamination. Samples were collected from sites throughout the Dampier Archipelago; both impact sites close to intensive shipping activity and remote control sites. TBT in this area originates mainly from commercial vessels using the Port of Dampier that are >25 m in length and exempt from legislation controlling the use of TBT in antifouling paints. A field survey was undertaken in July 1997; 100 M. granulata were taken at each of 18 sites with varying vessel activity, and examined for imposex. The level of TBT contamination in the Archipelago was low; ranging from <0.3 to 25 ng Sn l−1 in water,<0.3 to 80 ng Sn g−1 in oyster tissue (Saccostrea cuccullata – prey of M. granulata), and <0.3 to 33 ng Sn g−1 in whelks. Percentage of imposex in M. granulata ranged from 0% to 57%, and was correlated with distance to vessel activity (r=0.646, p<0.05). The only significant relationship of imposex with butyltin concentrations was with TBT in oysters (r=0.826, p<0.05), and dibutyltin (DBT) in whelks (r=0.783, p<0.05). It is postulated that this is because of interspecies variation in ability to metabolize TBT to DBT and MBT (monobutyltin), as well as induction of imposex in earlier life stages, so that imposex in adults could be a reflection of prior contamination. M. granulata is a suitable bioindicator of TBT contamination in the Dampier Archipelago, which could be used throughout the Indo-Pacific given its abundance in the region.  相似文献   

15.
The impact and recovery from exposure to the herbicide diuron [DCMU; 3-(3′,4′-dichlorophenyl)-1,1-dimethylurea] was assessed for three tropical seagrasses, maintained in outdoor aquaria over a 10-day period. Photosynthetic stress was detected using chlorophyll a fluorescence, measured with a Diving-PAM (pulse amplitude modulated fluorometer). Exposure to 10 and 100 μg l−1 diuron resulted in a decline in effective quantum yield (ΔF/Fm′) within 2 h of herbicide exposure in Cymodocea serrulata, Halophila ovalis and Zostera capricorni. Effective quantum yield also declined over the first 24 h of exposure in H. ovalis at even lower diuron concentrations (0.1 and 1.0 μg l−1). Effective quantum yield in H. ovalis and Z. capricorni was significantly depressed at all diuron concentrations (0.1–100 μg l−1) after 5 days exposure, whereas effective quantum yield in C. serrulata was only significantly lower in plants exposed to highest diuron concentrations (10 and 100 μg l−1). Effective quantum yield depression was present 5 days after plants exposed to 10 and 100 μg l−1 diuron were returned to fresh seawater. These results indicate that exposure to herbicide concentrations present in nearshore Queensland sediments present a potential risk to seagrass functioning.  相似文献   

16.
《Marine pollution bulletin》2009,58(6-12):503-514
Polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCs) are generally present in the marine environment in complex mixtures. The ecotoxicological nature of contaminant interactions, however, is poorly understood, with most scientific observations derived from single contaminant exposure experiments. The objective of this experiment was to examine dose-response relationships between antioxidant parameters and body contaminant levels in mussels exposed to different exposure regimes under laboratory conditions. Accordingly, the green-lipped mussel, Perna viridis, was challenged with a mixture of PAHs (anthracene, fluoranthene, pyrene, benzo[a]pyrene) and OC pesticides (α-HCH, aldrin, dieldrin, p,p′-DDT) over a 4 week period. Contaminants were delivered under four different dosing regimes, with all treatments receiving the same total contaminant load by the end of the exposure period. Antioxidant biomarkers were measured after 1, 2, 3 and 4 weeks, including glutathione (GSH), gluathione-S-transferase (GST), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and lipid peroxidase (LPO). GST and CAT were induced in hepatic tissues in most of the exposure regimes, with the majority of significant induction occurring in a constant exposure regime and a two-step alternate exposure regime. Significant differences among exposure regimes were detected in the body burden of contaminants after 28 days. Hepatic CAT and GSH are proposed as potentially useful biomarkers as they showed good correlation with target contaminants and were not readily affected by different dosing patterns.  相似文献   

17.
Persistent organochlorines such as polychlorinated biphenyls including coplanar congeners, DDT compounds and HCB were measured in different tissues (muscle, liver and eggs) of two Mediterranean shark species: namely Centrophorus granulosus and Squalus blainvillei. The concentrations of organochlorines in the tissues and organs of both species were in the order DDTs>PCBs>HCB. The highest values of DDTs, PCBs and HCB were found in liver followed by eggs and muscle. Among DDTs the compound found in greatest concentration was p,p′-DDE. The PCB profiles were dominated by congeners 138, 153, and 180. The isomers with higher TEQs values were non- and mono-ortho congeners than di-ortho ones in muscle, liver and eggs of both species. Among the non-ortho, PCB 126 was the major contributing individual to the total TEQs in both species.  相似文献   

18.
Responses of the green-lipped mussel Perna viridis (L.) to suspended solids   总被引：1，自引：0，他引：1  
Laboratory experiments were conducted to investigate the lethal and sublethal effects of suspended solids on the survival and physiological, behavourial and morphological changes of the green-lipped mussel Perna viridis collected from Tolo Harbour, Hong Kong. Results showed that P. viridis survived in all test conditions of suspended solids from 0 to 1200 mg/l over a period of 96 h. Physiological responses of the green-lipped mussel under 14-d exposure of suspended solids from 0 to 600 mg/l, followed by 14-d recovery in natural seawater, revealed no significant changes (p>0.05) in oxygen consumption and dry gonosomatic index for treatments in different concentrations of suspended solids and exposure time. Changes in clearance rate were only found to be significant (p<0.001) with exposure time. Responses in behavourial and morphological changes of the green-lipped mussel were also studied under similar experimental treatments and exposure time. Byssus production was significantly (p<0.001) related to exposure time. Gill damage, however, was significantly greater in treatments (p<0.001). Present findings suggested that P. viridis could tolerate a high level of suspended solids in the laboratory. There were dose-dependent effects of suspended solids on morphology of gill filaments. Implications of survival and responses of the green-lipped mussel to suspended solids in the marine environment are discussed.  相似文献   

19.
The paper presents the results of monitoring trace organic contaminants (17 PCBs and 7 OCPs) and 6 trace metals (Cd, Cr, Cu, Hg, Pb and Zn) in the coastal waters of the eastern Adriatic in 2006 using Mytilus galloprovincialis as indicator species. OCPs were found in all samples (0.07-14.3 ng g−1 d.wt.), while in positive samples concentrations of PCBs ranged between 0.16 and 20.5 ng g−1 d.wt. The α-HCH/γ-HCH and DDE/DDT ratios indicated recent input of γ-HCH and DDT. Spatial distributions of HCB, PCBs, DDTs and Hg were significantly correlated with population density. Although elevated concentrations of all trace metals and organic contaminants were recorded in the densely populated and industrialized areas, overall data point to relatively low level of contamination of the eastern Adriatic coast. Evaluation of the risks to human health associated with consumption of the mussels suggested that there is no health risk for moderate shellfish consumers.  相似文献   

20.
This in situ study used photosynthetic activity (measured as chlorophyll a fluorescence) and photosynthetic pigment concentrations to assess the effect of copper, cadmium, lead and zinc on the seagrass Zostera capricorni. Custom-made portable in situ exposure (PIE) chambers were developed so seagrasses could be dosed within the meadow. Z. capricorni was exposed to 0.1 and 1 mg l−1 of metal solutions for 10 h. During this time and for the subsequent four-day recovery period, the effective quantum yield of photosystem II (PS II) (ΔF/Fm′) was measured. While the results were variable, copper and zinc exposed samples had a depressed ΔF/Fm′ during the exposure period. Samples exposed to zinc recovered to pre-exposure levels but those exposed to copper did not. Cadmium and lead did not impact on the chlorophyll a fluorescence and the chlorophyll pigment data supported these findings. This study presents an innovative new application of chlorophyll a fluorescence stress assessment.  相似文献   

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