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1.
The concentration of 210Po, an alpha emitter from the natural uranium series was measured in the soft tissues (total), shell, and different organs - digestive glands, gills, mantle and foot - of the freshwater mussel, Parreysia favidens (Benson), collected from the river Kaveri, at Tiruchirapalli in South India. the analyses were made in three size groups based on shell length (Group 1: 2-4 cm; Group 2: 4-5 cm; Group 3: 5-6 cm). the soft tissues of the mussel accumulated higher concentrations of 210Po (74.0-125.5 Bq kg-1 fresh) than the shell (2.9-3.9 Bq kg-1 fresh). Further, younger mussels (1 group) showed higher concentrations (125.5+2.0 Bq kg-1 fresh) in total soft tissues than older ones (III Group) (74.0+1.6 Bq kg-1 fresh); concentration factors were 1.59x 105 in I group and 9.37 × 104 in III group. the 210Po was observed to be non-uniformly distributed among the internal organs, which maintained the following descending order with reference to 210Po accumulation: digestive glands, ranging from 286.2+3.5 Bq kg-1 fresh to 43+1.3 Bq kg-1 fresh. the concentration of 210Po in the mussels was distinctly higher than that in the grass, Echinochloa colonum (J. Koenig), and carp, Cirrhinus cirrhosa (Bloch), from the same river. These data indicate that younger mussels could be used as an excellent biological indicator of 210Po and among soft tissues, digestive glands are preferable to other tissues to monitor the distribution of 210Po in the riverine system.  相似文献   

2.
As part of a joint USA/USSR Environmental Agreement to determine the distribution and concentration of Chernobyl radioactivity in the northwest Black Sea area, the sediment from eight stations was collected and analyzed to assess the ability of this material to adsorb radiocaesium. Batch tests were conducted in which Cs-137 tracer was added to mixtures of sediment and bottom water, with contact solutions ranging from 85 Bq ml-1 to 1,760 Bq ml-1. This work was done in an argon atmosphere at 9.5°C, which is the average temperature of the sediment. Isotherms were linear for all cores and distribution ratios (RD) calculated from the slopes of the isotherms ranged from 660 to 1,660 ml g-1. These isotherms fit a simplified Freundlich isotherm. Correlations of RD to a number of sediment parameters describing texture and mineralogy were determined. A close relationship was observed between RD for caesium and the percentage of illite contained in the samples.  相似文献   

3.
To assess the natural and anthropogenic radiocontamination, sediment samples were collected in the Tigullio Gulf (Ligurian Sea). the results presented here indicate a significant Cs-137 contamination (about 20 Bqkg-1 dry weight) while concentrations of “primordial” natural radioisotopes were similar to those detected in other coastal areas. Gross sedimentation rates, determined through measurements of Be-7 concentrations, were at about 4-5 cm in the last 6 months. Natural and artificial radioactivity concentrations have been compared with data obtained in other Mediterranean areas. Heavy metals (Cu, Cr, Mn, Ni, Zn, Pb, Cd, Hg) concentrations were also determined inside the bay. Most elements displayed quite constant concentrations through the sediment core, except for copper which had showed highest concentrations in the top 16 cm of the sediment.  相似文献   

4.
Deep-sea sediments collected in two areas of the Mediterranean Sea having different sedimentological characteristics have been analyzed to determine present concentrations and inventories of 239,240Pu and to study the main mechanisms controlling them. Plutonium distribution in the deepest part of a submarine canyon (Taranto Valley, Ionian Sea) is compared to that obtained in an abyssal plain (north Algerian Plain). in the latter case, sedimentation is mainly due to the sinking of biogenic particles, while in the former lateral transport of terrigenous material along the slope of the canyon can significantly contribute to sediment accumulation on the bottom.

239,240Pu surface concentration in the canyon ranged from 0.2 to 1 Bq kg-1 (dry weight) and this was lower in the abyssal plain. in this area, plutonium was detectable only in the first 4 cm, while in the canyon it was present down to 11-15 cm. 239,240Pu inventories are 3 Bq m-2 in the plain and 45-60 Bq m-2 in the canyon, indicating considerable input of terrigenous material towards the final part of the Taranto Valley.  相似文献   

5.
污染源解析是城市大气环境精准防治的重要基础。为探究典型工业城市大气降尘中重金属污染分布特征和污染源解析,本研究在济南市域内采集了35个大气降尘样品,分析了样品中重金属浓度及其空间分布特征,采用正定矩阵因子分析模型(Positive Matrix Factorization,PMF)解析降尘中重金属来源。研究结果表明,降尘中Mn、Fe、Co、Ni、Cu、Zn、As和Pb浓度平均值分别为501.4、29884.6、8.2、24.8、44.3、153.9、12.5、40.1 mg·kg-1,其中Zn、Cu和Pb的地累积指数(Geoaccumulation Index,Igeo)分别为1.17、1.06和1.01,属于中度污染;钢铁冶炼较为发达的钢城区降尘中Mn、Fe、Co、Cu和As浓度显著高于其他区县,其浓度平均值分别为1172.4、73577.3、17.0、139.7、32.3 mg·kg-1,而Zn和Pb在历下区、槐荫区等人口密集区域最高浓度可达351.5 mg·kg-1和114.0 mg·kg-1;PMF分析结果表明,济南市降尘重金属主要存在4个贡献源,分别为土壤源、工业源、交通源和混合源,贡献率分别为46.8%、26.6%、15.2%和11.4%。其中,重金属Co、Cu、Fe主要来自土壤源,Mn主要来自于土壤源和工业源的贡献,Ni主要来自于土壤源和混合源,交通源对降尘中Pb和Zn的贡献率较高,As则主要来自于工业源。本研究结果可为济南市大气环境精准防控政策的制定提供理论依据。  相似文献   

6.
We studied Cs-137 contamination and radionuclide transfer in mountain forest ecosystems from Bulgaria. Here we show the first analyses of Cs-137 soil-to-plant transfer and we assess that it depends on the soil organic matter content and the specifics of the tree species. The forest litter is strong polluted with Cs-137 and is a barrier for its migration. In the upper 0-5 cm of the soil the Cs content ranges from 52 to 81 Bq kg–1 then decreases in deeper layers. The 1-year-old needles of spruce, fir, and Scots pine accumulate more cesium than the fine roots. The values of the needles transfer factor range between 0.3 and 0.58. The fine roots transfer factor varies between 0.1 and 0.32.  相似文献   

7.
137Cs in the marine environment mainly originates from fallout of atmospheric nuclear weapon tests, accidental releases from nuclear facilities, and from the Chernobyl accident. After the latter accident, many studies have been carried out in Turkey. The objective of this study is to assess the spatial distribution of 137Cs in the coastal marine environment of the Aegean Sea.

The concentrations of 137Cs in sediment, sea water, mussel (Mytilus galloprovincialis), and fish samples collected from the coast of the Aegean Sea at Izmir Bay and near Didim (Akbük) have been monitored for seasonal variability by the means of gamma spectroscopy: they vary between 0.10 ± 0.01 and 1.5 ± 0.3 Bq kg?1, 1.3 ± 0.1 and 4.3 ± 0.4 Bq m?3, <0.2 and 1.3 ± 0.3 Bq kg?1, and 0.20 ± 0.03 and 1.8 ± 0.3 Bq kg?1, respectively.  相似文献   

8.
三苯基锡(triphenyltin,TPT)和三丁基锡(tributyltin,TBT)在环境中经常同时存在,针对TBT对肥胖发生的影响已有较多研究,但TPT能否诱导肥胖的发生尚不明晰.本研究用环境水平的TPT(0.5、5和50 μg·kg-1)对青春期Sprague Dawley大鼠进行灌胃处理54 d后,测量大鼠体...  相似文献   

9.
建立了超高效液相色谱-串联质谱(UPLC-MS;MS)快速测定蔬菜中18种农药残留的方法.样品经乙腈提取后,经Oasis PRiME HLB固相萃取柱净化,采用ACQUITY UPLC HSS T3 C18(50 mm×2.1 mm,1.8μm)色谱柱进行分离,以0.1%甲酸水溶液和乙腈作为流动相进行梯度洗脱.采用电喷雾电离源、正离子模式下以多反应监测(MRM)进行定性和定量分析.结果表明,18种农药在0.5—50μg·L-1范围内线性关系良好(r2>0.995),方法最低检出限为0.4—1.5μg·kg-1,最低定量限为1.4—5.0μg·kg-1.在韭菜、芹菜、番茄、白菜基质中,5、10、50μg·kg-1添加水平下的加标回收率为60.2%—126.9%,相对标准偏差(RSD)为0.4%—21.6%(n=3).  相似文献   

10.
植物叶片汞浓度与大气气态单质汞(GEM/Hg0)浓度的线性关系表明叶片汞浓度大小可用于指示植物生长区内GEM浓度的高低水平.通过分析上海市绿地公园(25座)中常见落叶树木樱花、水杉、法桐叶片汞浓度的时空变化特征,探究区域内GEM含量水平及分布特征.2017年5-10月对7座公园中这3种树木叶汞浓度进行连续监测,结果显示...  相似文献   

11.
本文以不同Cd、Zn浓度胁迫下的长梗白菜为研究对象,采用盆栽实验,分析了Cd和Zn胁迫下长梗白菜形态参数(重量、长度、表面积、叶的分形维数)、生理性能的影响以及从土壤中提取Cd和Zn的能力.结果 表明,Cd、Zn胁迫对长梗白菜的生长具有"低促高抑"效应,且共同胁迫对生长的影响大于单一胁迫.在0.6 mg·kg-1 Cd...  相似文献   

12.
生物炭对土壤中阿特拉津吸附特征的影响   总被引:3,自引:0,他引:3  
为探究生物炭对土壤中阿特拉津的吸附特征及影响因素,采用批处理实验研究了灭菌(T1)、5%秸秆生物炭+灭菌(T2)、未灭菌(T3)和5%秸秆生物炭+未灭菌(T4)条件下对土壤中阿特拉津吸附特征及土壤理化性质的影响.结果表明,在最初0-12 h内,不同处理下阿特拉津吸附量均随时间的延长而快速增加,而在12-96 h内增加较...  相似文献   

13.
十溴联苯醚(BDE-209)对土壤跳虫的急、慢性毒性效应   总被引:1,自引:0,他引:1  
为揭示溴代阻燃剂对土壤生态系统的潜在危害,采用回避实验和繁殖实验评价了十溴联苯醚(BDE-209)对2种土壤跳虫Folsomia candida和Folsomia fimetaria的急/慢性毒性。48h的急性回避实验中,BDE-209对F.candida和F.fimetaria产生毒性效应的EC_(50)值分别为1.27和0.79mg·kg~(-1),LOEC值均小于0.5mg·kg~(-1)。慢性繁殖实验中,BDE-209对F.candida和F.fimetaria繁殖毒性的EC_(50)值分别为0.81和0.56mg·kg~(-1),LOEC值分别为<0.25和<0.5mg·kg~(-1)。研究表明,土壤BDE-209污染对跳虫的繁殖和环境行为有显著影响,且在较低暴露浓度下(0.25mg·kg~(-1))即对跳虫繁殖产生抑制效应;有性生殖的F.fimetaria比孤雌生殖的F.candida对BDE-209污染的毒性响应更为敏感。  相似文献   

14.
In spite of a worldwide reduction in the utilization of organochlorine pesticides (OCPs), they are still a problem for the aquatic environment and human health. The Black Sea is still being polluted with persistent chemicals, including OCPs. Aquatic organisms (sprat, scad, bluefish, shad, belted bonito, goby, and black mussel) with different feeding behaviours were sampled on a seasonal basis from the Bulgarian region of the Black Sea, and the concentrations of 13 OCP residues were determined. Although many of the OCPs were not detected in the samples, in all samples 1,1,1-trichloro-2,2-bis(4-chlorophenyl) ethane (DDT) was present mainly in the form of its metabolites 1,1-dichloro-2,2-bis(4-chlorophenyl) ethane (DDD) and 1,1-dichloro-2,2-bis(4-chlorophenyl) ethylene (DDE). Only about 12% of the total DDT was present as the parent compound pp-DDT, which suggests that it was not being used recently in the region. The total DDT concentrations were generally below 150 μg kg-1 fresh weight, but higher levels—up to 354 μg kg-1 fresh weight—were also measured for fish species with a high fat content. Between-species differences were observed, even when the concentrations were presented on a fat-level basis. DDT concentrations did not show any significant changes over the 2-yr sampling period. Fish sampled in the northern areas of the Bulgarian Black Sea coast seemed to contain higher DDT levels than those from the southern areas, suggesting a major (historical) influence of the Danube River. For permanent monitoring purposes, the utility of Black Sea gobies and scad should be considered.  相似文献   

15.
The Baltic Sea is, like the Mediterranean, a marginal sea, which with the Black Sea, were marine environments contaminated from the Chernobyl accident.

Radiocaesium and plutonium isotopes were studied in water, sediment and macroalgae in the Baltic Sea since 1982. the inventory of 137Cs in the Baltic increased from 0.65 PBq to 5.85 PBq following the Chernobyl accident. the corresponding increase for 239 + 240Pu was less significant and yielded 1.5 TBq to a total value of 16.5 TBq.

For plutonium, 98% is trapped in the sediment and the net-exchange of this element through the Baltic straits is very small (1 GBq/year), while for radiocaesium, 45% is in the water phase and there is a net-loss of 60 000 GBq annually into the adjacent water (Kattegatt).  相似文献   

16.
Endocrine disrupting compounds (EDCs), pharmaceuticals and personal care products (PPCPs) have attracted much attention due to widespread contamination in aquatic environment. In this study, we determined 13 EDCs and PPCPs in fish blood, bile and muscle by using gas chromatography-mass spectrometry (GC-MS). The limits of quantitation (LOQ) were in the ranges of 0.23–2.54, 0.22–2.36 ng·mL−1, and 0.24–2.57 ng·g−1 dry weight (dw) for fish blood, bile and muscle, respectively. Recoveries of target compounds spiked into sample matrices and passed through the entire analytical procedure ranged from 65% to 95%, from 60% to 92% and from 62% to 91% for blood, bile and muscle, respectively. The methods were applied to the analysis of fish from a lake in California. Target compounds were relatively low in bile, and only bisphenol A (BPA) and diclofenac were measurable near the LOQ. Seven of 13 compounds were detected in blood, with total concentrations up to 39 ng·mL−1. Only BPA was frequently found in muscle, with mean concentration of 7.26 ng·g−1 dw. The estimated daily intake of BPA through fish consumption for U.S. resident was significantly lower than the tolerable daily intake recommended by the European Food Safety Authority. This study showed that the exposure to the bisphenol A from fish diet is unlikely to pose a health risk.  相似文献   

17.
Adsorption and desorption of 137Cs by acid sulphate soils from the Nakhon Nayok province, South Central Plain of Thailand located near the Ongkarak Nuclear Research Center (ONRC) were investigated using a batch equilibration technique. The influence of added limestone (12 and 18 tons ha-1) on 137Cs adsorption-desorption was studied. Based on Freundlich isotherms, both adsorption and desorption of 137Cs were nonlinear. A large portion (98.26-99.97%) of added 137Cs (3.7 × 103-7.03 × 105 Bq l-1) was sorbed by the soils with or without added lime. The higher lime treatments, however, favoured stronger adsorption of 137Cs as compared with soil with no lime, which was supported by higher Kads values. The addition of lime, the cation exchange capacity and pH of the soil increased and hence favoured the stronger adsorption of 137Cs. Acid sulphate soils with a high clay content, medium to high organic matter, high CEC, and predominant clay types consisting of a mixture of illite, kaolinite, and montmorillonite were the main soil factors contributing to the high 137Cs adsorption capacity. Competing cations such as NH4+, K+, Na+, Ca2+, and Mg2+ had little influence on 137Cs adsorption as compared with liming, where a significant positive correlation between Kads and soil pH was observed. The 137Cs adsorption-desorption characteristics of the acid sulphate soils studied exhibited a very strong irreversible sorption pattern. Only a small portion (0.09-0.58%) of 137Cs adsorbed at the highest added initial 137Cs concentration was desorbed by four successive soil extractions. Results clearly demonstrated that Nakhon Nayok province acid sulphate soils have a high 137Cs adsorption capacity, which limits the 137Cs bioavailability.  相似文献   

18.
Samples of Mugil cephalus, Liza ramada, Siganus luridus, Siganus rivulatus, Epinephelus alexandrinus, Epinephelus areolatus, Epinephelus fasciatus, Epinephelus chlorostigma, Cephalopholis argus and Cephalopholis sonnerati were collected from the Mediterranean and Red Seas and their muscle and bone analyzed by AAS for some trace metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, Pb). the results showed that these metals accumulate in the bones to a greater extent than in the muscle. the highest accumulated element is cobalt (4.7-20.8 times), while the lowest is lead (1.1-2.5 times). the accumulation is more pronounced in Red Sea species than in Mediterranean species. the elevated levels of lead in Mugil cephalus (2.6-3.0 mg kg-1) and Epinephelus alexandrinus (3.0-3.9 mg kg-1) were attributed to the intake in food in the polluted environment of Alexandria coastal water. the relationship between body size and concentration of trace metals using a standard linear regression technique gives a significant positive correlation for cobalt, manganese, iron and lead in the muscle, as well as for lead in the bones of Mugil species from the Red Sea, while the Mediterranean species showed little correlation.

There is a tendency for increased concentrations of the essential metals manganese, iron and copper with increasing trophic level of the fish, while the opposite is true for the toxic metals chromium and lead. Our results indicate that there is no risk from toxic metal concentrations in muscle of fish from the Mediterranean and Red Seas consumed by man even in contaminated areas.  相似文献   

19.
Heavy metals are increasingly being released into natural waters from geological and anthropogenic sources. The distribution of several heavy metals (Cr, Cu, Cd, Pb, Zn, and Hg) was investigated in muscle, gill, and liver in two different fish species seasonally collected in El-Mex Bay (autumn 2004-summer 2005). In order to evaluate the pollution status of the Bay, the concentrations of the selected metals in the labile and total fractions were analysed in sediment samples collected from eight sites in El-Mex Bay during autumn 2004. Also, the Index of Geoaccumulation (Igeo) for the sediment was estimated. The total and labile fractions of the selected metals in sediment samples were 15.2 and 62.8 μg g-1 dw for Cu, 1.8 and 5.0 μg g-1 dw for Cd, 79.1 and 130.3 μg g-1 dw for Zn, 0.2 and 1.2 μg g-1 dw for Hg, 35.8 and 93.0 μg g-1 dw for Pb, and 13.9 and 31.0 μg g-1 dw for Cr. The concentrations of all metals were lower in flesh than those recorded in liver and gill due to their physiological roles. The metal pollution index for fish was calculated. Health hazard calculations for the contaminated sediments and fish consumption were calculated to evaluate the effect of pollution on health.  相似文献   

20.
Precise and sensitive methods for the simultaneous determination of different classes of antibiotics, including sulphonamides, fluoroquinolones, macrolides, tetracyclines, and trimethoprim in surface water, sediments, and fish muscles were developed. In water samples, drugs were extracted with solid-phase extraction (SPE) by passing 1000 mL of water through hydrophilic lipophilic balanced (HLB) SPE cartridges. Sediment samples were solvent-extracted, followed by tandem SPE (strong anion exchange (SAX) + HLB) clean-ups. Fish muscles were extracted by a mixture of acetonitrile and citric buffer (80:20, v/v) solution, and cleaned by SPE. Liquid chromatography–tandem mass spectrometry (LC-MS/MS) with multiple reaction monitoring (MRM) detection was employed to quantify all compounds. The recoveries for the antibiotics in the spiked water, sediment, and fish samples were 60.2%–95.8%, 48.1%–105.3%, and 59.8%–103.4%, respectively. The methods were applied to samples taken from Dianchi Lake, China. It showed that concentrations of the detected antibiotics ranged from limits of quantification (LOQ) to 713.6 ng·L-1 (ofloxacin) in surface water and from less than LOQ to 344.8 μg·kg-1 (sulphamethoxazole) in sediments. The number of detected antibiotics and the overall antibiotic concentrations were higher in the urban area than the rural area, indicating the probable role of livestock and human activities as important sources of antibiotic contamination. In fish muscles, the concentration of norfloxacin was the highest (up to 38.5 μg·kg-1), but tetracyclines and macrolides were relatively low. Results showed that the methods were rapid and sensitive, and capable of determining several classes of antibiotics from each of the water, sediment, and fish matrices in a single run.  相似文献   

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