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101.
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
102.
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
103.
PCBs in fish from the southern Baltic Sea: levels, bioaccumulation features, and temporal trends during the period from 1997 to 2006 总被引：1，自引：0，他引：1
Levels of seven marker polychlorinated biphenyls (PCBs) have been determined in five species of Baltic fish collected during 1997-2006. Downward time trends in the concentrations of heavier congeners of PCBs in different Baltic fish, with the exception of cod, have been observed between 1997 and 2001. In case of sprat and herring samples, the statistical significance of the time trends of the PCBs: 101, 118, 153, 138 and 180 concentrations has been proved. Species-specific bioaccumulation of PCBs has been indicated, and the lowest and highest levels of PCBs (expressed on the basis of lipid weight) have been observed in sprat and salmon samples, respectively. PCB profiles have been found to be similar in all the fish species tested. Sampling location has not been a crucial factor for the observed levels of various PCBs. In some fish species, PCB concentrations are negatively correlated with the fat content but have no relation with the fish length. 相似文献
104.
Recent declines in Chesapeake Bay oyster populations have been attributed to disease, and reduced water quality from pollution. The stress associated with pollutant exposure may reduce energy available for growth and reproduction. Polychlorinated biphenyls (PCBs) are lipophilic contaminants that may potentially affect mobilization of lipid reserves, increasing reliance on glycogen stores, which could otherwise be utilized to supply energy for gametogenesis. Thus, PCBs may indirectly affect glycogen stores in oysters in a deleterious manner. To test for this effect, reproductively inactive oysters were exposed to PCBs by feeding individuals 0.7 g of algal paste containing 0, 0.35, or 3.5 μg PCBs daily for 8 weeks. Additionally, a group of oysters was exposed to PCBs (0, 0.35, and 3.5 μg) plus 0.3 g of non-toxic artificial sediment to examine interactive effects of sediment particles and PCBs. Adductor muscle, mantle, and gonadal tissues were analyzed for glycogen content. Results suggest that glycogen content is reduced in the adductor muscle with increasing PCB exposure, but there are no effects of PCBs in the mantle and gonadal tissues. 相似文献
105.
《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
106.
Marine mussels, Perna viridis, were transplanted from a reference site to various polluted sites around Hong Kong. After 30 d of exposure, antioxidative responses in the gills and hepatopancreas and tissue concentrations of chlorinated hydrocarbons [polychlorinated biphenyls (PCBs) and chlorinated pesticides (CPs)] were determined for individual mussels. Glutathione S transferase (GST) and glutathione (GSH) were positively correlated with tissue PCB concentrations. Only one of the enzymatic antioxidants, glutathione peroxidase (GPx), showed significant response to tissue PCB. No significant correlation was found between tissue concentrations of chlorinated hydrocarbons and other enzymatic antioxidants (superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) and NADPH DT-diaphorase (DT-d). Oxidative stress, measured as thiobarbituric acid reactive substances, was correlated with chlorinated pesticide concentrations in tissues. This study demonstrated a correlation between GST/GSH and chlorinated hydrocarbons. The apparent lack of correlation between trace organic pollutants and some of the enzymatic antioxidants may be due to the inhibitory effects caused by these chemicals. The above results suggest that more investigations are needed before these enzymes can be used as biomarkers. 相似文献
107.
De Luca-Abbott SB Richardson BJ McClellan KE Zheng GJ Martin M Lam PK 《Marine pollution bulletin》2005,51(8-12):694-707
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
108.
加速溶剂提取/GC-MS同时测定动物组织中有机氯农药和多氯联苯 总被引：1，自引：1，他引：0
动物组织样品油脂含量大、干扰杂质多,对其中低含量有机氯农药及多氯联苯的分析会造成较大程度的影响。针对动物组织样品基质复杂的特点,本文以二氯甲烷-丙酮（体积比为1：1）的溶剂体系,采用加速溶剂萃取技术对样品进行提取,在提取过程中尽量减少脂肪的共提出,然后采用凝胶渗透色谱技术去除样品中的大部分油脂,再结合弗罗里硅土为填料的固相萃取方法对样品进一步净化,能够达到充分去除油脂和小分子杂质的目的。采用气相色谱-质谱分析17种有机氯农药及7种指示性多氯联苯,各化合物的回收率在81.6%~113.4%之间,检出限在1.02~3.59 ng/g之间,技术指标优于部分国家标准。本方法改进了动物样品的净化效果,建立了凝胶渗透色谱结合固相萃取技术的净化方法,达到了样品快速自动提取、溶剂用量少、基质净化彻底的目的,降低了方法检出限,能够满足快速、准确检测动物组织中低含量持久性有机污染物的要求。 相似文献
109.
To distinguish between adsorbed and absorbed PCBs in seawater microorganisms, 2,2′,4,4′,5,5′-hexachlorobiphenyl (IUPAC #153; HCB) was added to a pure culture of Chrysochromulina apheles Moestrup et H.A. Thomsen. After the addition of the HCB, the cells were immediately harvested onto 2 μm polycarbonate filters and rinsed with a gradient of ethanol concentrations. Rinsing with 40% ethanol (v/v) was found to remove 80% of the HCB, which was loosely adsorbed to the cell surfaces, but did not extract the interior of the cells, as tested by chlorophyll a analysis. This method was used in a time course experiment which estimated PCBs adsorption and absorption to different groups of plankton organisms. Three different 14C-PCBs, 4-chlorobiphenyl (IUPAC #3; MCB), 2,2′,5,5′-tetrachlorobiphenyl (IUPAC #52; TCB), and 2,2′,4,4′,5,5′-hexachlorobiphenyl (IUPAC #153, HCB), were incubated in seawater from the northern Baltic Sea during a spring bloom. Samples were taken every third day and separated by filtration into three fractions; 0.2–2 μm (bacteria), 2–10 μm (flagellates), and >10 μm (microplankton; phytoplankton and protozoa). Two subsamples were retained from each size fraction. One of the subsamples was left untreated, to obtain adsorbed plus absorbed PCB, while the other subsample was rinsed with 40% of ethanol, to obtain the absorbed PCB. The sorption was found to vary depending on the hydrophobicity of the compounds, the structure of the cell membranes, and the lipid content and composition of the cells. The absorption increased for the TCB and the HCB in the largest size fraction over time, which coincided with an increase of the neutral and non-polar lipids. 相似文献
110.
The long term systematic investigations of ion composition components (bicarbonates, chlorides, sulphates, magnesium, calcium, sodium, potassium) and trophic status components (suspension, chlorophyll-a, mineral and organic forms phosphorus and nitrogen, carbon, silica) of water from the lake proper, its tributaries and atmospheric precipitation, which make up the main share of substance supply in to the lake, as well as the Angara river, being the source of substance discharge allowed the lake recent state to be evaluated in terms of both chemical pollution and possible eutrophication of its water. The similar (in terms of river runojf) periods of 50-ies and 80-ies have been compared. It was revealed that as a result of industrial activity 409 thousand tons of mineral substances (27.2 thousand tons of chlorides, 162 thousand tons of sulphates and over 200 thousand tons of organic substances) are supplied in the lake annually. The supply of substances of the anthropogenic origin is higher for the South Baikal than that for the North and Middle Baikal (the sum of mineral substances in 3.6 times; sulphates in 5 times, organic substances, including hydrocarbons in 7 times).The absence of abundant phytoplankton in the period studied when the ratio of silica to phosphorus is optimum (over 100), as well as a revers correlation between winter nitrogen content and spring of chlorophyll-a concentration in the Baikal water and revers dependence between the suspension and chlorophyll-a along the Selenga river valley lead to the conclusion that Baikal water contains toxicants. It is verified by the presence of polychlorbiphenyls (PCB), poly-chlordibenzo-p-dioxins (PCDD) and dibenzofurans (PCDF) for the whole food web with the maximum PCDD/PCDF (TEQ to 175 P g · g-1) concentration in the seal blubber. The levels are comparable with those reported for ringed seal (phoca hispida), living in the Baltic sea and Bar-row Strait Inlet in the Canadian Arctic. 相似文献