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1.
Six organotin species – tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT), triphenyltin (TPT), diphenyltin (DPT) andmonophenyltin (MPT) – have been determined in seawater (255 samples), sediments (85 samples) and bivalves (558 samples) collected at seventeen locations in the southwest of Spain in five occasions between May 1992 and August 1994. No phenyltinspecies were found but butyltin species were present in all the stations. The TBT concentrations ranged between 23 and 1500 ng g-1 Sn in biota, from less than 0.6 to 160 ng g-1 Sn in sediments and from less than 0.5 to 31 ng L-1 Sn in water, with the highest values closely related with boating activity and decreasing according to the distance from the potential sources. For biota and water, a consistent seasonal pattern of fluctuation of TBT concentrations was evident, with the highest values found in spring and summer except for a fishing harbour. A slow decreaseof TBT concentration was observed between 1992 and 1994. Percentages of DBT and MBT in biota (22±7 and 13±6,respectively) were lower than those in water (33±10 and 31±15, respectively) and sediments (48±16 and 25±16, respectively). Sediment-water partition coefficients for TBT were 240–65 000 and bioconcentration factors 17 000–350 000. This article discusses the significance of the pollution in our study area in comparison with other world coastal areas.  相似文献   

2.
The extent of pollution with organotin compounds was investigated in water, sediment and bivalve mussels (Mytilus galloprovincialis) from the Northern Adriatic Sea. Butyl-, phenyl- and octyltin species were quantified after extraction and derivatisation by gas chromatography–mass spectrometry in a total of 99 samples from the period from 2000 to 2006. The accuracies of the analytical procedures were checked by spiking of unpolluted water samples and by the analysis of standard reference materials (harbour sediment PACS-2 and mussel tissue ERM-CE 477). Among organotin species analysed in samples butyltins were the predominant. Tributyltin was found to be present in the highest concentrations, suggesting its recent input into the marine environment. Butyltins were detected at all sites surveyed (sum of butyltins was up to 718 ng Sn L?1, 3,552 ng Sn g?1 d.w. and 9,991 ng Sn g?1 d.w. in water, sediment and mussel samples, respectively), phenytins in much lower concentrations (up to 31 ng Sn L?1, 326 ng Sn g?1 d.w. and 442 ng Sn g?1 d.w. in water, sediment and mussel samples) and to a much smaller extent, while octyltins were not detected at any location. The spatial distribution of tributyltin was closely related to boating, with the highest concentrations found in marinas (up to 586 ng Sn L?1 for water samples, 1,995 ng Sn g?1 d.w. for sediment and 6,434 ng Sn g?1 d.w. for mussel samples). The temporal distribution clearly indicates a decrease of organotin pollution at all sites.  相似文献   

3.
In order to elucidate the details of both the distribution and fate of organotin compounds (OTs) in the costal ecosystem, the concentrations of butyltin compounds (BTs) and phenyltin compounds (PTs) were determined in seawater, sediment and blue mussels Mytilus galloprovincialis collected in Maizuru Bay, Japan. The concentrations of tributyltin (TBT) in seawater, sediments and mussels ranged from 3.9 to 27 ng l?1, from 1.2 to 19 ng g?1 dry wt and from 0.77 to 11 ng g?1 wet wt, respectively. Although the levels of TBT in seawater, sediments and mussels from Maizuru Bay were lower than those reported previously at other sites in Japan, the levels can still be toxic to susceptible organisms. Trace amounts of PTs were also found in seawater, sediment and mussel samples, indicating that there is a slight input of triphenyltin (TPT) into the seawater in the bay at present. The highest TBT concentration in seawater among all sites measured in the bay was found near a glass factory, and the lowest concentrations were observed at the center of the bay. The highest concentration of TBT in sediment was detected near a shipyard. In mussels, a high concentration of TBT was detected near a cement plant and timberyard. These results indicate that the major sources of contamination of OTs in the bay are considered to be from those facilities and ships. The proportion of TBT in seawater and mussels showed that, of total BTs, it was the predominant compound at most sites. These results suggested that there is a continuous input of TBT into the seawater and thereafter an accumulation of TBT in mussels due to their low metabolic capacity to degrade TBT. In sediment, the proportion of monobutyltin (MBT) was the highest of BTs at most sites. This could reflect a previous contamination by TBT used before the regulation of its usage in the bay.  相似文献   

4.
Concentrations of organotin compounds in sediments from four sites in the Göta älv estuary, SW Sweden, rangefrom 17 to 366 ng/g dw for tributyltin (TBT) and from1.5 to 71 ng/g dw for triphenyltin (TPT), similar toresults from other harbours and marinas and from an earlier study in the Göteborg Harbour, which is located in the estuary. Also dibutyltin, monobutyltin, diphenyltin and monophenyltin, the degradation products of TBT and TPT, werefound. TBT concentrations are the highest in the inner harbour and in the upper sediment layer of ca. 10 cm, indicating the risk for mobilisation of TBT bound in surface sediments in thefrequently disturbed harbour environment.  相似文献   

5.
The stored nitrogen in perennial plants plays an important role in their regrowth in spring. Free L-arginine is one of the major forms of stored nitrogen (6, 9) .. LArginine is metabolized via the urea cycle in animal and plant tissues. In animal tissues, L-arginine is also metabolized via r-guanidinobutyramide, r-guanidinobutyric acid, and r-aminobutyric acid to the TCA cycle. In plant tissues, few attempts have been made to study arginine-metabolic routes other than the urea cycle. In white spruce tissues (3), L-arginine is metabolized via r-guanidinobutyric acid. Also in citrus tissues (4, 5), the operation of the same metabolic route has been reported. In these experiments, it was observed that various guanidino compounds reacted with the Sakaguchi reagent.

To obtain more information about the guanidino compounds involved in the arginine metabolism, the analytical system was evaluated and the presence of these compounds in several plant species was examined.  相似文献   

6.
In a partly urbanized catchment to the south of Trier, Germany, short term variations in river sediment compounds as well as the bioaccumulation of pollutants on surface associated microbial coatings (biofilms) were investigated weekly during a period of six months. Concentrations of selected heavy metals (Cu, Zn, Pb), polycyclic aromatic hydrocarbons (PAH), polychlorinated biphenyls (PCB) and for microbial characterisation protein, carbohydrate and uronic acid were analyzed. Sorption processes on biofilms were determined by temporal variations in pollutants and microbial parameters and through the comparison of sorbed substances in biofilms and sediments. The results show, that sorption events on biofilms play an important and dynamic role in spring and summer for transport and accumulation of the investigated pollutants in the aquatic environment. The amount of pollutants sorbed on sediment particles is not only dependent on the particulate bound or solved pollutants in the river water, but is strongly controlled by the changing conditions of the biofilms.  相似文献   

7.
以水培试验为基础,比较了3种挺水植物在抑菌和不抑菌条件下对培养液中毒死蜱的降解作用。结果表明,植物处理系统中毒死蜱的去除率显著高于无植物对照,不抑菌条件下的显著高于抑菌条件下(P〈0.05);不同植物处理系统,植物和微生物对毒死蜱的降解贡献差异较大。水生鸢尾、水葱和菖蒲的去除贡献分别为39.98%、62.37%和65.29%,微生物的去除贡献分别为41.28%、17.92%和13.79%,植物的贡献起主导作用。抑菌条件下植物生物量增量低于不抑菌条件下的,微生物对植物生长有促进作用。  相似文献   

8.
A wide variety of veterinary antibiotics (VAs) has been detected in environmental water samples, and this is of potential environmental concern due to their adverse effects. In particular, the potential for development of antibiotic-resistant bacteria has raised social concerns leading to intensive investigation regarding the influence of antibiotics on human and ecosystem health. One of the main sources of antibiotic effluence to the environment is livestock manures that often contain elevated levels of VAs that survive normal digestive procedures following medication in animal husbandry because unlike human waste, waste generated on farms does not undergo tertiary wastewater treatment, and consequently, the concentration of antibiotics entering the environment is expected to be larger from farming practices. Animal feed is often supplemented with VAs to promote growth and parasite resistance in the medicated animals, and this practice typically resulted in higher use of VAs and consequential excretion from livestock through urine and feces. The excretion rate varied depending on the type of VA used with around 75, 90, and 50?C100% being excreted for chlortetracycline, sulfamethazine, and tyolsin, respectively. The excreted VAs that initially present in livestock manures were degraded more than 90% when proper composting practice was used, and hence, this can be employed as a management strategy to decrease VA environmental loads. The reduction of VA concentrations during composting was mainly attributed to abiotic processes rather than biotic degradation. The VAs released to soils by the application of manure and manure-based composts can be degraded or inactivated to various degrees through abiotic process such as adsorption to soil components. Depending on the antibiotic species and soil properties, residues can be transferred to groundwater and surface water through leaching and runoff and can potentially be taken up by plants.  相似文献   

9.
10.
水系物质迁移过程示踪及其在环境中的应用   总被引:1,自引:0,他引:1  
水是环境中污染物迁移的重要介质,水系污染物也可以直接作用于生物体。本文概述了对水系物质迁移过程示踪的各种方法,包括人工示踪剂方法、生物标志法、微量元素及同位素示踪方法等,指出了它们的环境应用价值。在人工示踪法中叙述了中子活化示踪沙技术和稀土元素-DTPA螯合物示踪法。生物标志物主要叙述了木质素、正构烷烃、脂肪酸的指示意义。微量元素示踪主要涉及到Sr、Ca、Mg和REE的示踪。同位素示踪法着重阐述了较先进的碳、氮、氧和铅同位素的示踪。最后展示了水系物质示踪的应用前景。  相似文献   

11.
The use of solid phase extraction and capillary GLC provides thebasis for the selective determination of phthalate ester plasticizers in rivers and marine water samples. Of the severalsolvent ratios (methanol in dichloromethane) used for selective elution of phthalate esters from the C18 solid phase glass catridge, the 50/50 ratio, CH3OH in CH2Cl2 (v/v)gave the best result. The method was tested on river and marinewater samples that receive effluent from industries that use phthalate esters. The rivers and marine water samples were grossly polluted as several phthalate esters, for example, dimethyl (DMP), diethyl (DEP), dibutyl (DBP) and diethylhexyl (DEHP)were present at 0.03–2306±9.4 μg L-1. A study on uncontaminated water was done to establish background levels.  相似文献   

12.
13.
创造适宜河溪生物栖息环境是河溪生态恢复的主要目标之一。总结了近年来国内外在该领域的研究成果,指出人工化的河溪或平缓顺直的、激流的河溪通常不能为河溪生物提供良好的栖息环境。从构建河道内生物栖息地的措施出发,论述了创造深潭-浅滩结构、改变河床底质以及一些直接提供生物栖息环境等生态河溪建筑物的特点、作用、功能和可行性。最后提出在中国开展创造河溪生物栖息环境生态工程研究应注意的问题和发展方向,以期对我国河道的生态治理有所裨益。  相似文献   

14.
The levels of radioactive contamination by artificial radiocesium (137Cs) were evaluated in sediments and the commonest species of water plants. Specimens were collected from a range of biotopes along the Pinios River and its tributaries, during the years 1998 and 2010. The 137Cs concentrations within the above period clearly indicate that this radionuclide still decrease in the River Pinios. A marked decrease is also observed in comparison to our previous results in 1993. 137Cs concentration activities in the sediment are higher than in the plant material. In general, roots showed greater 137Cs concentration than leaves, while stems showed the lowest concentration. Significant differences in 137Cs concentrations were found among different species growing under similar environmental conditions. 137Cs content in collected aquatic plants was in the descending order: Ceratophyllum demersum L. > Myriophyllum spicatum L. > Paspalum pasalodes Scribner > Cladophora glomerata L. > Cyperus longus L. > Potamogeton nodosus Poiret. A comparison of the studied stations indicated that the southwest side of Thessalia plain, where the first two initial sampling stations of the Pinios River and the tributaries Enipeas and Kalentzis are situated, was highly contaminated. Low 137Cs concentrations were observed in the Titarisios tributary, originated from the northeast part of Thessalia plain, behind Mt. Olympus and the last sampling stations of the Pinios River.  相似文献   

15.
郁家成  王胜 《中国农业气象》2004,25(2):62-64,F003
在分析国内外工厂化养殖现状的基础上,论述了水产设施环境和生产管理方面存在的问题。明确指出了养殖设施中的温度、光照和水质等环境小气候要素是影响工厂化养殖发展的关键环境因素,提出了温室环境小气候调控的途径和措施。  相似文献   

16.
Medicines and their metabolites have been found as water contaminants at very low concentrations; moreover, there is no extensive toxicological data to determine the risks associated with their occurrence in water resources. The ibuprofen genotoxicity potential to the Oreochromis niloticus fish (Tilapia), due to nanograms per liter exposure, was evaluated using the micronucleus test. Acute (48 h) and sub-chronic assays (10 days) were carried out at 300 ng/L ibuprofen aquatic concentration comparing with the negative control group (without treatment), with eight animals per group. The results were assessed from the average of triplicate analyses. The micronucleus frequency in peripheral blood of fish was determined using a sample size of 3,000 erythrocytes per animal. Significance was defined using t test (p????0.05). The bioassay results showed a statistically significant increase in the frequency of micronuclei for both exposure times in comparison to the negative control. The micronucleus frequency observed for the sub-chronic tests was higher than the one identified in the acute assays. The observed ibuprofen genotoxic effects demonstrated an aquatic environmental risk of this pharmaceutical, which occurs for the used fish experimental model in lower concentration than previously described for other aquatic organisms.  相似文献   

17.
During May–September 1999, several aquatic environmental samples were collected from the village of Caimito, in the San Jorge River basin area, state of Sucre (Colombia), and analyzed for total mercury (T-Hg). Mean T-Hg concentration in sediments from surrounded marshes was 0.155 ± 0.016 g Hg/g. Low Hg concentrations were found in the phytoplanktivorous fish species Prochilodus magdalenae (0.087 ± 0.01 g Hg/g), while four-fold greater concentrations were found in all the carnivorous species. In average, T-Hg concentrations for fish samples did not exceed the limit consumption level (0.5 g Hg/g). However, risk assessment based on the hazard index suggested that the consumption of 0.1 kg per day of carnivorous fish could increase the risk of mercury poisoning in local population.  相似文献   

18.
19.
Li  Jinhui  Tang  Hongxiao  Bai  Qingzhong  Nie  Yongfeng  Luan  Zhaokum 《Water, air, and soil pollution》2000,117(1-4):251-261
With the aggravation of acid rain pollution and the enlarging of the acid rain regions in China, the sensitivity evaluation of natural waters to acidification on a regional scale become increasingly important. Acidification models based on a single indicator cannot give much information on aquatic acidification because of their simplicity; yet acidification models based on physical, chemical, hydrological and/or biological processes are not suitable for large scale regional research because of their exceptional complexity. In this paper, a multi-indicator comprehensive model for aquatic acidification sensitivity is proposed and applied. This model comprises some of the most important factors that are considered to influence water acidification, in particular: acid neutralization capacity, acidification capacity, acidification sensitive index, cation exchange capacity of soil, pH of soil, and weathering shuck types of soil-forming. It highlights the key stages of aquatic acidification by acid neutralization capacity, acidification capacity, and acidification sensitivity index. The model thereby estimates the acidification sensitivity of natural waters by using these indicators according to a weighting system. Equal-weight and non-equal-weight approaches are separately used to combine the six indicators into an overall sensitivity index of aquatic acidification. The result derived from an application to China on a national scale indicates the practicability of this approach. In China, the sensitive natural waters emerge in Southern China, which is already a heavy acid rain region, and in Northeastern China where the rainwater is beginning to become much acidic.  相似文献   

20.
Nonylphenol (NP), nonylphenol mono- and di-ethoxylate (NP1EO, NP2EO) and bisphenol A (BPA) were determined in water, suspended particulate matter (s.p.m.) and bed sediment collected from the most polluted stretch of Tiber river (Italy) in the neighbourhood of Rome. Analytes were recovered from water samples by solid-phase extraction (SPE) on Si–C18 cartridges and analysed by HPLC with fluorescence detection. Solid samples were extracted by using an aqueous solution of the non-ionic surfactant Tween 80. Results indicated that 2–42% of NP, 9–45% of NP1EO, 11–18% of NP2EO and 4–62% of BPA respectively occurred in the suspended phase. In general, for all compounds a higher affinity for s.p.m. than for bed sediments was observed, reflecting differences in the nature of particles and in their sorption capacity for organic micro-pollutants. The partition of target compounds in river compartments was affected by differences in hydrological conditions between the two sampling campaigns. Run-off from the basin or resuspension/redissolution from sediments was an important source of nonylphenol and bisphenol A during high discharge regimes. Partition coefficients of compounds (log K oc ) between water and s.p.m. were calculated under stable flow condition. K oc values, experimentally measured in the river, were higher than those predicted by K ow , implying that specific chemical interaction could occur in the sorption mechanisms for these group of compounds.  相似文献   

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