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1.
Polychlorinated biphenyls (PCBs) are an important group of environmental pollutants, there being a total of 209 theoretical congeners. Residue analysis of the adipose tissue of five species of fish-eating sea birds from British and Irish coastal waters revealed the presence of up to 60 different congeners. By GC-MS, GC-MSD and high resolution capillary GC-ECD using authentic standards, it was possible to identify and quantify 40 different congeners. Despite the large number of PCB congeners identified only 10 accounted for > 80% of the total PCBs. A PCB congener was identified accounting for 5% of the total PCBs (2,3′,4,4′,5′,6-hexachlorobiphenyl) [168] not usually reported in biological samples. Comparison of the molecular structure for the persistent PCB congeners revealed the lack of meta-para unsubstituted adjacent carbon atoms. It has been shown that meta-para unsubstituted adjacent carbon atoms facilitate the metabolism of PCBs and it is hypothesised that the formation of hydroxy derivatives may depend upon such a requirement. 相似文献
2.
R.J. Norstrom D.C.G. Muir C.A. Ford M. Simon C.R. Macdonald P. Bland 《Marine environmental research》1992,34(1-4)
Selective accumulation of PCDDs, PCDFs and PCB congeners was investigated in beluga (Delphinapterus leucas), narwhal (Monodon monoceros) and several species at the same trophic level in two areas of Canada. There was a much higher relative abundance of meta-para-unsubstituted PCBs in the cetaceans compared with other species. This suggests that activity of cytochrome P450 monooxygenase enzymes causing CYP2B-type metabolism was relatively low in beluga and narwhal. Lower relative levels of 2,3,7,8-TCDD occurred in beluga from both areas, and selective reduction of toxic non-ortho PCBs occurred in the highly PCB-contaminated St Lawrence beluga. These compounds are potent inducers of cytochrome P450 CYP 1A-type enzymes, suggesting that such an enzyme with the capability of metabolizing TCDD-like substrates is present in beluga and narwhal. SIMCA principal components analysis of PCB congener patterns showed that the two cetaceans were in a statistically significant different class than the other species. Variables (congeners) with the greatest separation power between classes were mainly those defined by the selective metabolism rules. 相似文献
3.
Spatial Distribution of Polychlorinated Biphenyls （PCBs） Contaminants in the Tidal-flat Sediments of Yangtze Estuary 总被引：1，自引：0，他引：1
1 IntroductionYangtze River estuary is the biggest one in China, and there are domestic and manufactural rubbish disposal sites for Shanghai city in this tidal-flat. The Shanghai city, the whole Yangtze delta, or even all the Yangtze basin, will be PCBs contaminant sources of Yangtze estuary tidal-flat[1]. According to literatures so far, only two investigations for waters have included PCBs in the Yangtze estuary[2, 3]. No PCBs pollution of the tidal-flat sediments has been reported… 相似文献
4.
Polychlorinated biphenyls(PCBs) were measured in atmospheric samples collected from the North Pacific to the Arctic Ocean between July and September 2012 to study the atmospheric concentration characteristics of PCBs and their gas/particle partitioning. The mean concentration of 26 ∑PCBs(vapor plus particulate phase)(∑PCBs) was 19.116 pg/m3 with a standard deviation of 13.833 pg/m3. Three most abundant congeners were CB-28,-52 and-77, accounting for 43.0% to ∑PCBs. The predominance of vapor PCBs(79.0% to ∑PCBs) in the atmosphere was observed. PCBs were negative correlated with the latitudes and inverse of the absolute temperature(1/T). The significant correlation for most congeners was also observed between the logarithm of gas/particle partition coefficient(log KP) and 1/T. Shallower slopes(from-0.15 to-0.46, average-0.27) were measured from the regression of the logarithm of sub-cooled liquid vapor pressures(logpo L) and log KP for all samples. The difference of the slopes and intercepts among samples was insignificant(p0.1), implying adsorption and/or absorption processes and the aerosol composition did not differ significantly among different samples. By comparing three models, the J-P adsorption model, the octanol/air partition coefficient(KOA) based model and the soot-air model, the gas/particle partitioning of PCBs in the Arctic atmosphere was simulated more precisely by the soot-air model, and the adsorption onto elemental carbon is more sensitive than the absorption into organic matters of aerosols, especially for lowchlorinated PCB congeners. 相似文献
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6.
Blubber samples, taken through the entire blubber column, were collected from three different anatomical locations on ringed seals (Phoca hispida). The outer and inner layers of these samples were analysed for concentrations of sigma PCBs (sum of the analysed congeners, polychlorinated biphenyls) and p,p'-DDE (4,4'-dichlorodiphenyldichloroethylene). No significant differences were found in blubber thickness or in per cent extractable lipid when comparing age- and sex-groups, or in extractable lipid content when comparing anatomical locations of the blubber or blubber depth. No significant differences were found between the three different anatomical locations with respect to the concentrations of sigma PCBs or p,p'-DDE. However, the concentrations of both sigma PCB and p,p'-DDE were significantly higher in the outer blubber layer compared to the inner. Higher levels of both sigma PCB and p,p'-DDE were found in males compared to females and juveniles in both the inner and outer parts of the blubber column. The most commonly used blubber sampling devices are biopsy tools that penetrate only the outer layer of the blubber. Analyses of such samples will not reflect the real body burden of organochlorines. Standard methods for sampling blubber of marine mammals should be developed so that comparative studies and longitudinal monitoring programs of pollutants in marine mammals can be conducted in a meaningful way. 相似文献
7.
Polychlorinated biphenyls (PCBs) are relict contaminants, while polybrominated diphenyl ethers (PBDEs) are in increasing use. Using sediment cores collected in the Strait of Georgia, we demonstrate that the surface sediment concentration of PCBs is largely determined by environmental processes, such as sediment accumulation and mixing rates, while that of PBDEs is strongly influenced by proximity to source. The Iona Island wastewater outfall appears to be a primary pathway for PBDEs. As well, Vancouver Harbour is highly contaminated with both classes of chemical. BDE-209, the main component of deca-BDE, is the dominant PBDE congener. Environmental debromination is not evident. Currently, the ranges of the surface concentration of PCBs and PBDEs are similar to one another, but that will change in the future, as the concentration of PBDEs continues to rise. The experience with PCBs suggests that if PBDEs were banned today, it would take decades for inorganic sediment to bury them. 相似文献
8.
中华白海豚(Sousa chinensis)组织中多氯联苯的研究 总被引：1，自引：0，他引：1
以珠江口海域的两头中华白海豚为研究对象,采用气相色谱法分析了海豚组织中多氯联苯（PCBs）的含量分布特征和毒性水平。结果表明,PCBs在海豚10种不同组织中的含量范围为25．1—85567．3ng／g,PCBs含量最高的组织为额隆和皮肤,其次为肝脏、肌肉、心脏、睾丸和脑,最低的为肺、胃和肾脏;PCBs同系物和同族物在海豚不同组织中的分布特征相似,同系物中以PCB101＋113和PCB153所占总量的百分比最大,在10．25％-51．70％之间;在同族物中以含在同族物中以5个氯原子和6个氯原子的PCBs为主,所占百分比均在23．53％-60．06％之间;运用二蛞哄毒性当量（TEQ）评价了中华白海豚不同组织中PCBs的毒性,其TEQs范围为55．9—68191．0pg／g,其中皮肤TEQs含量最高。TEQs主要来自非邻位取代的PCBs,占总量的74．15％-99．62％,其中来自PCB126的占34．11％-96．5I％。与世界其他海域海豚的PCBs污染水平相比,成年中华白海豚受PCBs污染严重,其体内的PCBs含量和毒性当量均已超出安全浓度范围,对其健康已造成威胁。 相似文献
9.
R J Pruell B K Taplin D G McGovern R McKinney S B Norton 《Marine environmental research》2000,49(1):19-36
A laboratory experiment was conducted to investigate the transfer of organic contaminants from an environmentally contaminated marine sediment through a simple marine food chain. The infaunal polychaete, Nereis virens, was exposed to contaminated sediment collected from the Passaic River, NJ, USA, for 70 days. These polychaetes were then fed to the American lobster, Homarus americanus, for up to 112 days. Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), 2,4,6,8-tetrachlorodibenzothiophene (TCDT), polychlorinated biphenyls (PCBs), and several chlorinated pesticides were accumulated by polychaetes following exposure to the contaminated sediment. Some of these contaminants were also accumulated by lobsters which were exposed to the contaminated sediment and/or fed contaminated polychaetes. Only the lesser chlorinated PCDDs and PCDFs (mostly tetra- and pentachlorinated congeners) and 2,4,6,8-TCDT were detected in the polychaetes and lobster. Significant alterations were noted in the PCB patterns found in both species, particularly the lobster. The non-ortho-substituted PCBs (such as congeners 77 and 126) became enriched in the PCB mixtures of the polychaetes and especially the lobsters relative to the sediment, probably because these congeners were not metabolized. These congeners and the 2,3,7,8-tetrachlorodibenzo-p-dioxin toxicity equivalents of the PCB mixtures were enriched by a factor of about six in the lobsters relative to the sediment. Elimination of PCB congeners containing vicinal hydrogens in the meta-para region is consistent with cytochrome P450IIB-type metabolism. Based on the concentration trends for some PCB congeners and chlorinated pesticide ratios measured in the lobsters during this experiment, it appears that this metabolic system is inducible in the American lobster. 相似文献
10.
Impact of polychlorinated biphenyls (PCBs) on the immune function of fish: age as a variable in determining adverse outcome 总被引：3，自引：0，他引：3
Polychlorinated biphenyls (PCBs) are a major contaminant of global extent in water resources and aquatic biota. Due to its high lipid solubility, PCBs fail to be degraded and, therefore, continue to bioaccumulate throughout the environment and food chain. To determine the impact of PCBs on the immune system of aged and juvenile Japanese medaka (Oryzias latipes), fish were injected with the coplanar PCB congener 126 and examined after 3 and 14 days. PCB 126 produced oxidative stress in both age groups of fish 14 days post-injection; however, juvenile medaka appeared more susceptible than aged fish. Humoral immunity, as determined by antibody forming cell (AFC) numbers, was significantly depressed for up to 14 days post-injection in both age groups. These results demonstrate the sensitivity of the fish immune response for predicting PCB-induced immunotoxicity and identify age as a variable in determining adverse outcome. 相似文献
11.
Field concentrations of polychlorinated biphenyls (PCBs) were measured in sediment and nine marine soft bottom invertebrate species. Lipid- and organic carbon normalised biota-sediment accumulation factors (BSAFs) were determined for 29 nonplanar and 11 coplanar congeners. To investigate whether the bioaccumulation was in thermodynamic equilibrium with the sediment, the determined BSAFs were compared to theoretically calculated ones to obtain a BSAFdet./BSAFtheor-ratio. Large interspecific variations were found: one suspension feeding and one deposit feeding species of brittle stars (Amphiura filiformis and A. chiajei), and one predatory polychaete (Glycera rouxii) had ratios>1 for congeners with logKow>6.5. In these species there was also a linear relationship between logKow and BSAF, both for coplanar and for planar congeners but with lower values for coplanar ones. For other species the pattern was more scattered. Only the deposit feeding polychaete Melinna cristata had BSAFdet./BSAFtheor-ratios<1 for all congeners. Thus, the interspecific variations in bioaccumulation did not correlate with differences in feeding strategies, but may be caused by differences in biotransformation, and in age and size of the analysed specimens. 相似文献
12.
《Marine environmental research》1999,47(1):1-15
Brain, liver and muscle samples from seven male beluga whales, Delphinapterus leucas, from Hendrickson Island in the Canadian Arctic (n=3) and the St. Lawrence River estuary (n=4), were analyzed for polychlorinated biphenyls (PCBs) and other organochlorine (OC) compounds to determine whether there are differences in the distribution of these contaminants in beluga tissues and between geographic locations. Wet weight concentrations of ΣPCB, ΣDDT, Σchlordane and mirex were significantly higher (p<0.05) in St. Lawrence samples. Principal component analysis (PCA) of the PCB and OC data indicated that contaminant profiles in belugas from the St. Lawrence reflect point-source inputs of these compounds while Arctic samples appear to be dominated by PCB congeners and OC compounds subject to long-range transport and deposition. Discriminant functions analysis of the contaminant data for the brain, liver and muscle tissues indicated that the distributions of OC compounds in the liver and muscle tissues were very similar, while brain samples could be distinguished from other tissues by differences in PCB congener patterns and higher concentrations of Σhexachlorocyclohexane (ΣHCH), primarily αHCH. 相似文献
13.
Comparison of sampling devices for the determination of polychlorinated biphenyls in the sea surface microlayer 总被引：1，自引：0，他引：1
García-Flor N Guitart C Bodineau L Dachs J Bayona JM Albaigés J 《Marine environmental research》2005,59(3):255-275
Over 30 sea surface microlayer (SML) samples from two contrasting sites in the North Western Mediterranean -- Barcelona (Spain) and Banyuls-sur-Mer (France) -- were collected using three different sampling devices, namely, glass plate, metal screen (MS) and a surface slick sampler (SS), and compared with the corresponding underlying water (16 samples). The distributions of 41 polychlorinated biphenyl congeners (PCBs) were determined in the different phases: particulate (1.17-10.8 SigmaPCB ng L(-1)), truly dissolved (0.080-16.7 SigmaPCB ng L(-1)) and colloidal matter (1.17-43.0 SigmaPCB ng L(-1)), being the last two estimated from the analysis of the apparently dissolved phase. Concentrations of PCBs in the SML were higher than those in the underlying water (ULW), giving rise to enrichment factors (EF=[C](SML)/[C](ULW)) up to first-order of magnitude. The ANOVA statistical approach was used to assess differences of bulk data (e.g. dissolved organic carbon, DOC; particulate organic carbon, POC; suspended particulate matter, SPM) among sampling devices, whilst p-tailed t paired tests were used in order to compare the enrichments obtained for each sampling date. In this respect, no significantly different enrichment factors were found among sampling devices (p < 0.05), although the surface SS showed lower enrichments, probably due to the dilution of the SML with the ULW during sampling. The MS seemed to be the most suitable device for the determination of PCBs in the SML in terms of sampling efficiency under a variety of meteorological conditions. 相似文献
14.
June-Soo Park Olga Ioanna Kalantzi Dianne Kopec Myrto Petreas 《Marine environmental research》2009,67(3):129-135
Bioaccumulation of endocrine disruptors in marine mammals positioned at the top of the food chain is of toxicological concern. Livers from four pups and ten adult harbor seals (Phoca vitulina) stranded in San Francisco Bay (SFB) and the Gulf of Maine (GOM) were analyzed for polychlorinated biphenyls (PCBs) and their hydroxylated metabolites (OH-PCBs). We used GC–ECD and GC–NCI/MS to investigate the presence of 28 PCBs and 8 OH-PCB metabolites, respectively. Σ28PCB concentrations (di- to octa-CBs) ranged from 1.81 to 35.9 μg/g lipid with a median of 6.53 for the seal pups and 2.31 to 249 μg/g lipid with a median of 28.9 for the adult seals. Σ8OH-PCB concentrations (penta- to hepta-OH-PCBs) ranged from 0.02 to 0.69 μg/g lipid with a median of 0.04 for the adult seals, i.e., at much lower concentrations than those for PCBs. Ratios of OH-PCBs to PCBs (0.24% on average) were comparable to those in beluga whale, but were lower than ratios in human livers. The OH-PCB profiles were slightly different between SFB and GOM seal livers, although similar PCB congener patterns were observed. Generally, 4-OH-CB107 was found predominantly in seal livers and was the only OH-PCB detectable in most of seal pup livers. This study provides information on OH-PCBs in seals, adding to the scarce exposure data for these chemicals. 相似文献
15.
Midlittoral polychaete communities in the Eastern Mediterranean Sea: new information from the implementation of the Natural Geography in Shore Areas (NaGISA) protocol and comparisons at local and regional scales 
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下载免费PDF全文 Georgios Chatzigeorgiou Kleoniki Keklikoglou Sarah Faulwetter Fabio Badalamenti Miltiadis‐Spyridon Kitsos Christos Arvanitidis 《Marine Ecology》2017,38(1)
The aim of this study was to attempt to fill current knowledge gaps on midlittoral Mediterranean biodiversity at local and regional scales, by using benthic polychaetes as a model taxon. Two different data sets were analysed: (i) a quantitative data set from the two Natural Geography in Shore Areas (NaGISA) study sites in Crete and (ii) a qualitative data set from multiple sites across the Mediterranean. At the local scale, the results provide evidence that (i) discrete species communities are formed in midlittoral Mediterranean habitats, which vary by geographical location and year, depending on the scale of observation; (ii) macrophyte coverage and Chl‐a are the only environmental variables associated, albeit weakly, with the above pattern; (iii) although naturally disturbed, the Cretan NaGISA sites do not seem to experience any anthropogenic stress; (iv) environmental heterogeneity and history seem to be much less important in shaping the polychaete communities than inter‐specific interactions; however, it is not possible to specify at this stage whether local or regional processes or even their interactions may shape the polychaete communities. At the regional scale, the results indicate that (i) the only factor that seems to be involved in the regional pattern is the identity of the study providing the data sets, which implies variability and bias in how research projects are carried out, from the sampling design through to data collection and analysis; (ii) the Cretan NaGISA sites may be considered as representative of the habitat in the Mediterranean, under certain conditions. 相似文献
16.
Magnusson K Magnusson M Ostberg P Granberg M Tiselius P 《Marine environmental research》2007,63(1):67-81
Bioaccumulation factors (BAFs) were determined for (14)C-PCB 101 and (14)C-PBDE 99 in the pelagic copepod Calanus finmarchicus after exposure to either contaminated water or after being fed contaminated phytoplankton (the dinoflagellate Prorocentrum minimum or the diatom Thalassiosira weissflogii). BAFs in algae range from 7.6 to 8.0 for PCB 101 and from 8.5 to 8.6 for PBDE 99. BAFs in copepods were significantly lower, 6.3-6.8 for PCB 101 and 7.6 for PBDE 99. For each compound, the BAFs in copepods were independent of what algal species they had consumed, even though the bioaccumulation of both compounds were higher in P. minimum than in T. weissflogii. The ratios between BAF and the K(ow) for PCB 101 and PBDE 99 were similar within each of the three species, but varied between species. For copepods the ratios were 2-4, for T. weissfloggii 15-22 and for P. minimum 32-40. The data strongly suggest that the two compounds bioaccumulate in a similar manner and that there is no biomagnification in the transfer between phytoplankton and herbivorous copepods. 相似文献
17.
N. García-Flor C. Guitart M. balos J. Dachs J.M. Bayona J. Albaigs 《Marine Chemistry》2005,96(3-4):331-345
Over 50 seawater samples from two different sites—Barcelona (Spain) and Banyuls-sur-Mer (France)—were analyzed in order to study the extent and postulate the processes driving the enrichment of hydrophobic organic pollutants in the sea surface microlayer (SML). A number of individual polychlorinated biphenyl (PCB) congeners (41) were measured to study their partitioning between the particulate (fraction > 0.7 μm) and the dissolved + colloidal phases (fraction < 0.7 μm), with the latter being differentiated into estimated dissolved and colloidal phases. In addition, several organochlorine pesticides were also measured, namely, HCB, α-HCH, γ-HCH, 4,4′-DDE, 4,4′-DDD and 4,4′-DDT. The presence of PCB congener profiles found in the SML suggests a dynamic coupling with the atmosphere in Banyuls sampling site, whereas offshore Barcelona the presence of highly chlorinated congeners was due to persistent sediment resuspension. The average PCB concentration in the SML dissolved + colloidal phase were higher in Banyuls (7.8 ng L− 1) than in Barcelona (3.6 ng L− 1) samples, but in the particulate phase concentrations were higher in Barcelona (3.2 ng L− 1) to that of Banyuls (1.4 ng L− 1). However, PCB concentrations in the SML generally also showed large variability. Enrichment factors of PCBs and other organochlorine compounds in the SML with respect to the underlying water column ranged from 0.2 to 7.4. This may be explained for both the dissolved + colloidal and particulate phases by the enrichment in the SML of organic carbon (OC) as discerned from particle–water and colloid–water partitioning. 相似文献
18.
SYLVIE LABROUE PHILIPPE GASPAR JOEL DORANDEU OZ ZANIFé F. MERTZ PATRICK VINCENT 《Marine Geodesy》2013,36(3-4):453-481
The Jason-1 sea state bias (SSB) is analyzed in depth from the first year of GDR products. Compared to previous missions, this work benefits from two aspects of the empirical determination of the SSB from the altimetric data themselves. First, from a methodological point of view, a nonparametric technique (NP) has been developed and largely tested on TOPEX/Poseidon 1, GFO and Envisat data. The NP estimator has proven to be a useful tool in the SSB estimation, and it is now mature enough to be used for a refined analysis. On the other hand, the SSB can be extracted from three different data sets (crossovers, collinear data, and residuals) with different characteristics. It is then possible to cross calibrate various estimations of the SSB models and to determine the most accurate one. A systematic comparison is made between these different estimates for the Jason-1 altimeter. The collinear and crossover data sets yield very similar estimates despite their difference of spatial and temporal distributions. These SSB models assure consistency with the TOPEX mission when comparing Jason-1 and TOPEX residuals during the tandem phase. Thanks to the present work, the impact of the short wavelengths filtering on the SSB estimation is evidenced. More generally, our understanding of potential errors affecting the sea surface height and their impact onto the SSB estimation is also improved. 相似文献
19.
Sylvie Labroue Philippe Gaspar Joel Dorandeu Oz Zanif F. Mertz Patrick Vincent Denis Choquet 《Marine Geodesy》2004,27(3):453-481
The Jason-1 sea state bias (SSB) is analyzed in depth from the first year of GDR products. Compared to previous missions, this work benefits from two aspects of the empirical determination of the SSB from the altimetric data themselves. First, from a methodological point of view, a nonparametric technique (NP) has been developed and largely tested on TOPEX/Poseidon 1, GFO and Envisat data. The NP estimator has proven to be a useful tool in the SSB estimation, and it is now mature enough to be used for a refined analysis. On the other hand, the SSB can be extracted from three different data sets (crossovers, collinear data, and residuals) with different characteristics. It is then possible to cross calibrate various estimations of the SSB models and to determine the most accurate one. A systematic comparison is made between these different estimates for the Jason-1 altimeter. The collinear and crossover data sets yield very similar estimates despite their difference of spatial and temporal distributions. These SSB models assure consistency with the TOPEX mission when comparing Jason-1 and TOPEX residuals during the tandem phase. Thanks to the present work, the impact of the short wavelengths filtering on the SSB estimation is evidenced. More generally, our understanding of potential errors affecting the sea surface height and their impact onto the SSB estimation is also improved. 相似文献