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91.
JIANG Jinhua 《海洋学报(英文版)》2009,28(6):111-117
The bioaccumulation of ten polychlorinated biphenyl (PCB) congeners was investigated within different tissues in three prawns (Penaeusorientalis Kishinouce, Laomedia astacina de Haan and Penaeus vannamei Boone) and one mud crab (Scylla serrata Forsskal) from mixed-aquaculture ponds in Taizhou in April 2007. The average concentrations (wet mass) of Σ PCBs in muscle, head, and rind tissues for mean among these prawn species were 7.04, 21.16, and 11.47 ng/g, respectively. The average concentrations of Σ PCBs in muscle, branchia, and spawn in Scylla serrata were 6.49, 21.13, and 19.76 ng/g, respectively. The concentrations of CB28 were the highest in prawn tissues (2.40 ng/g), and accounted for 18.60% of Σ PCBs. The concentration of CB52 was the lowest. The application of principal component analysis (PCA) for the estimation of PCB sources of contamination resulted in first component main contributions of CB101, CB153 and CB28 in the muscle, head, and rind in combined prawn samples, respectively. The enrichment level of Σ PCBs for different tissues varied greatly. The accumulation coefficient of Σ PCBs in prawn muscle, head, and rind tissues were 396.35, 1 191.79, and 645.91, respectively. For the Scylla serrata, the accumulation coefficients were 365.81, 1 190.50, and 1 113.31 for muscle, branchia, and spawn tissues, respectively. For prawns, the accumulation coefficient of CB153 was the highest in muscle tissues, while CB155 had the highest coefficients in the head and rind tissues. The CB155 coefficient was the highest in spawn tissues of the mud crab. 相似文献
92.
We have shown previously that exposure of Atlantic croaker to a PCB mixture (Aroclor 1254) results in impaired reproductive neuroendocrine function. In addition, we have identified hypothalamic tryptophan hydroxylase (TPH), the rate-limiting enzyme in serotonin (5-hydroxytryptamine) synthesis, as a target of PCB neuroendocrine toxicity. In order to further elucidate the mechanisms of PCB neurotoxicity, the present study investigated whether PCB-induced decrease in hypothalamic TPH activity resulted from degradation of the enzyme protein. Fish were exposed to Aroclor 1254 in the diet (0.1 mg/100 g body weight (BW)/day) for 30 days. The PCB exposure elicited a significant decrease in hypothalamic TPH protein content, which could be at least partially responsible for the reduced TPH activity. To test whether a similar PCB exposure could cause oxidative damage in croaker hypothalamic tissues, we examined the formation of malondialdehyde (MDA) protein adducts as a marker of lipid peroxidation (LPO). The same dose of PCB increased the MDA-protein adduct formation in the hypothalamus. In a separate experiment, the role of vitamin E, an antioxidant, to prevent or decrease the effect of PCB on hypothalamic TPH activity and gonadal growth was examined. The vitamin E co-treatments (1 and 10 mg/100 g BW/day) with PCB significantly reduced the effects of PCB on TPH activity and gonadal growth. These results suggest possible involvement of oxidative processes in PCB neurotoxicity. 相似文献
93.
Margaret O. James Kevin M. Kleinow Youbo Zhang Ran Zheng Liquan Wang Laura R. Faux 《Marine environmental research》2004,58(2-5):343
Benzo(a)pyrene (BaP) and polychlorinated biphenyls (PCBs) often co-exist in contaminated environments. Polychlorobiphenylols (OH-PCBs), formed by CYP-dependent monooxygenation of PCBs, are potent inhibitors of the glucuronidation of hydroxylated BaP metabolites. We hypothesized that OH-PCBs could drive the biotransformation of (−)BaP-7,8-dihydrodiol (BaP-7, 8-D) away from detoxication and towards formation of the reactive metabolite. A mixture of five OH-PCBs with 4–6 Cl atoms was infused into isolated, perfused, biliary intact livers (n=3 fish) removed from 3-methylcholanthrene-induced channel catfish. Controls (n=3) were infused with vehicle. Subsequently, [3H]-BaP-7, 8-D was infused into each liver and bile was collected for 1 h. The livers were taken for analysis of metabolites and DNA adducts. Induction status was confirmed by EROD assay. Bile was analyzed for metabolites. It was found that preinfusion of the mixture of OH-PCBs reduced the extent of glucuronidation of BaP-7, 8-D and increased the formation of DNA adducts 5-fold over controls. GSH conjugates, tetrols and triols were increased in the OH-PCB-infused fish, providing further support for our hypothesis that if the glucuronidation were inhibited, CYP-dependent activation would increase. These studies suggest a mechanism for synergy of toxicity of PAH and PCBs. 相似文献
94.
翡翠贻贝对多氯联苯吸收不同途径的比较研究 总被引：5，自引：0，他引：5
定量分析和比较翡翠贻贝Perna viridis对多氯联苯(PCBs)吸收的4种不同途径。结果表明，翡翠贻贝通过食物途径富集PCBs比从海水吸收的途径具更高效率；而通过底泥或悬浮颗粒积累PCBs的途径较为次要。翡翠贻贝对5—7个氯原子数的PCBs异构体富集率高，分别占PCBs总量的53．25％-77．41％。结果还表明，贻贝经沉积物途径和经滤食悬浮颗粒途径比经水途径和食物途径对含2—4个氯原子数和8—10个氯原子数的PCBs异构体富集率较高。 相似文献
95.
多氯联苯(PCBs)是一种具有亲脂性、低水溶性、高稳定性和高生物富集性等特性的持久性有机污染物(POPs),而沉积物作为疏水性有机污染物(HOCs)的重要地质宿体,PCBs在POPs中发生的环境过程是研究的热点。本文综述国内外近几年来沉积物中PCBs分析测定以及迁移转化的研究动态,并对今后PCBs污染的生物修复研究提出了自己的见解。 相似文献
96.
Polychlorinated biphenyls (PCBs) as Σ21 congeners, were investigated in atmospheric bulk deposition over one year, along a northern transect of France, including 5 sites from the Atlantic coast to the east of Paris. Evidence was obtained for an easterly rise of the PCB concentrations, from 3 to 76 ng L−1. The PCB patterns were depleted in low chlorinated congeners in rural areas whereas at urban sites, the profiles were typical of local sources. The seasonal variations of concentrations were mainly controlled by the temperature. Next, at Paris, PCB distribution between the gaseous and the particulate phases was studied, considering seasonal parameters and different fate processes. Their distribution showed a prevalence of congeners in the gaseous phase (0.15–1.17 ng m−3) which occurrence decreased from 93 to 68% with the rise of congener chlorination level. In the particulate phase, they ranged from 0.01 to 0.27 ng m−3, only. Rainwater concentrations ranged from 3.1 to 13.1 ng L−1. A total rain water/air washout ratio was determined and showed a negative correlation with those reported in the literature. That might be attributed to the importance of particle scavenging. The annual bulk deposition ranged from 8 to 29 μg m−2. A decreasing trend of PCB atmospheric levels over the last fifteen years was confirmed in the studied area. 相似文献
97.
1 INTRODUCTION While wastewater discharge regulations have significantly reduced water column pollution, historical and accidental releases of organic pollutants and heavy metals continue to pose an ecological threat as these contaminants have become 搃n-place?sediment pollutants. It had been previously assumed that natural attenuation processes, such as burial or biodegradation, would decrease the contamination levels in surface sediments and, thus, diminish the environmental impact of t… 相似文献
98.
《Marine pollution bulletin》2014,78(1-2):77-84
The distributions of 41 polychlorinated biphenyls (PCBs) were determined in the aqueous phase, suspended particulate matter (SPM), and sediment of the Daliao River estuary in Liaodong Bay, Bohai Sea (China). The total PCB concentrations ranged from 5.51 to 40.28 ng L−1 in the surface water, from 6.78 to 66.55 ng L−1 dry weight in the SPM, and from 0.83 to 7.29 ng g−1 dry weight in the sediment. The PCB concentrations in water, SPM, and sediment were moderate relative to those reported for other estuary and marine systems around the world. Sedimentary PCB concentrations decreased offshore due to the active deposition of laterally transported river-borne particles. The predominance of the highly chlorinated congeners for the water, SPM, and sediment samples are an indication of either a lack of degradation or the presence of nearby or recent releases into the environment. 相似文献
99.
A separation procedure was developed for analysis of polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) in urban air, while simultaneously eliminating the interfering compounds. This was carried out by optimization of a column chromatograph with regard to the eluent type (n‐hexane and n‐pentane), volume of eluent, type of sorbent material (silica gel and florisil) and activation level of the sorbent material. The determination of the level of PCBs and PAHs was carried out using gas chromatography (GC) equipped with a mass selective detector (MSD), while determination of the OCPs was carried out by GC equipped with an electron capture detector (μ‐ECD). The use of a silica gel column (10 g, 5% deactivated with H2O) with 70 mL of n‐hexane gave satisfactory separation of PCBs from PAHs and OCPs. After collecting the PCBs with 70 mL of n‐hexane, 3·20 mL of n‐hexane:ethyl acetate, (1:1, v:v) was adequate for elution of the PAHs and OCPs from the column. The primary aim of this study was to develop a multimethod for analyses of PCBs, PAHs, and OCPs in urban air as well as reducing solvent and sorbent consumption and analysis time during the clean‐up procedure compared to the US EPA standard methods (EPA methods TO‐13A for PAHs and TO‐4A for both PCBs and OCPs). 相似文献
100.
Ichiro Takeuchi Kaoruko Mizukawa Tokutaka Ikemoto Kotaro Tsuchiya 《Marine pollution bulletin》2009,58(5):663-9029
Biomagnification profiles of polycyclic aromatic hydrocarbons (PAHs), alkylphenols, and polychlorinated biphenyls (PCBs) from the innermost part of Tokyo Bay, Japan were analyzed using stable carbon (δ13C) and nitrogen (δ15N) isotope ratios as guides to trophic web structure. δ15N analysis indicated that all species of mollusks tested were primary consumers, while decapods and fish were secondary consumers. Higher concentrations of PCBs occurred in decapods and fish than in mollusks. In contrast, concentrations of PAHs and alkylphenols were lower in decapods and fish than in mollusks. Unlike PCBs, whose concentrations largely increased with increasing δ15N (i.e. increasing trophic level), all PAHs and alkylphenols analyzed followed a reverse trend. Molecular weights of PAHs are lower than those of PCBs, therefore low membrane permeability caused by large molecular size is an unlikely factor in the “biodilution” of PAHs. Organisms at higher trophic levels may rapidly metabolize PAHs or they may assimilate less of them. 相似文献