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1.
The objective of this paper is to synthesize results from seven published research papers employing different experimental approaches to evaluate the fate of metal-based nanoparticles (Ag NPs, Au NPs, CuO NPs, CdS NPs, ZnO NPs) in the marine environment and their effects on two marine endobenthic species, the bivalve Scrobicularia plana and the ragworm Hediste diversicolor. The experiments were carried out under laboratory (microcosms) conditions or under environmentally realistic conditions in outdoor mesocosms. Based on results from these seven papers, we addressed the following research questions: (1) How did the environment into which nanoparticles were released affect their physicochemical properties?, (2) How did the route of exposure (seawater, food, sediment) influence bioaccumulation and effects?, (3) Which biomarkers were the most responsive? and (4) Which tools were the most efficient to evaluate the fate and effects of NPs in the marine environment? The obtained results showed that metal‐based NPs in general were highly agglomerated/aggregated in seawater. DGT tools could be used to estimate the bioavailability of metals released from NPs under soluble form in the aquatic environment. Both metal forms (nanoparticulate, soluble) were generally bioaccumulated in both species. Among biochemical tools, GST and CAT were the most sensitive revealing the enhancement of anti-oxidant defenses in both species exposed to sub-lethal concentrations of metal-based NPs. Apoptosis and genotoxicity were frequently observed.  相似文献   

2.
采用Fenton氧化与生化组合技术处理生物难降解的采油废水的研究结果表明 ,Fenton氧化技术不但对采油废水中有机质有较好的去除率 ,而且大大地改善了废水的可生化性 ,在H2 O2 的投加浓度和Fe2 + 与H2 O2 的摩尔比分别为10mmol/L和 0 .1的条件下 ,经过 30min氧化后可使废水BOD值由原来的 5mg/L上升至 4 0mg/L ;同时随着氧化时间的延长 ,废水中残余的有机物分子量逐渐降低。 30min氧化后的废水经过生物处理 ,其出水COD值为 10 2mg/L ,可以满足国家综合污水外排标准 ,经济分析结果表明 ,该技术处理采油废水的运行成本为 1 4 7元 /t。这一技术在解决石油行业采油废水的外排达标方面具有很好的应用前景。  相似文献   

3.
Wind T  Werner U  Jacob M  Hauk A 《Chemosphere》2004,54(8):1135-1144
A computer simulation of the environmental concentrations of some typical consumer-product ingredients was performed using the geo-referenced exposure model GREAT-ER (Geo-referenced Regional Environmental Assessment Tool for European Rivers) in the river Itter. Boron and LAS were chosen as typical detergent ingredients along with EDTA, NTA and Triclosan as examples of household and cosmetic product ingredients. The simulations were based on consumption figures of the respective chemical in consumer products in the year 2000. For EDTA, the consumption figure used for the calculation had to be extended to commercial products since the EDTA-use in domestic products could not account for the measured concentrations alone. The resulting PEC (Predicted Environmental Concentration) for all investigated compounds showed very good accordance to the measured concentrations in the Itter which were monitored in the same year. The concentrations did not deviate more than by a factor of 3. GREAT-ER's calculated 90th-percentile was never exceeded by the monitoring result thus reflecting a reasonable accuracy.  相似文献   

4.
The photosystem II-herbicide diuron is widely used for weed control in Champagne's vineyards. Its important use and its relative persistence make it of particular interest for ecotoxicological studies. Toxicity of diuron was assessed on Lemna minor L., a representative aquatic macrophyte regularly used for toxicological studies. Toxicity assessments were based on inhibition of growth and total chlorophyll content of L. minor cultures after 7 days. Growth was inhibited and IC(50) and IC(90) were, respectively, 25 and 60 microg l(-1), but chlorophyll content of L. minor increased in response to the herbicide. When diuron was combined with copper, growth inhibition of L. minor depended on the concentrations of both chemicals. For some concentrations, combination of these chemicals resulted in a slight (but non-significant) antagonism. Additivity was observed for all other mixtures. When diuron was combined with folpet, growth and chlorophyll content of L. minor only depended on the concentration of the herbicide. Diuron was also found to prevent the copper-induced decrease of chlorophyll content when it was combined with this metal. A multifactorial model was found more appropriate to characterize interactions between pesticides than Abott's model.  相似文献   

5.
Growth of the Scots pine (Pinus sylvestris) suffered considerably in forests close to fur farms in western Finland, with the occurrence of winter time dieback in the youngest shoots and leading to a bush-like, flat crown canopy. One reason for this growth disturbance may be a serious imbalance in nitrogen metabolism caused by the extra N supply, emitted as NH3 from the dung of the animals. Total N and NH4+ concentrations in the needles and soluble nitrogen concentration in the soil increased considerably in the vicinity of the fur farms. The extra N in the needles was bound in the first place in arginine, the concentration of which increased 10(2)-10(3) fold compared with control trees, and to a lesser extent in glutamine and other amino acids. Alterations in the quantitative and qualitative protein patterns of the needles were obtained. The extra N increased the concentration of total soluble proteins, although it inhibited the formation of certain polypeptides (particularly in the areas of 30, 38, 50 and 65-90 kDa) which were possibly essential for the normal wintering processes. One reason for the winter time dieback in the high N area could thus be found in the altered protein profiles.  相似文献   

6.
A greenhouse pot experiment was conducted to evaluate the effect of sewage sludge (SS), of sugar beet sludge (SBS), or of a combination of both, in the remediation of a highly acidic (pH 3.6) metal-contaminated soil, affected by mining activities. The SS was applied at 100 and 200 Mg ha(-1) (dry weight basis), and the SBS at 7 Mg ha(-1). All pots were sown with Italian ryegrass (Lolium multiflorum Lam.). After 60 d of growth, shoot biomass was quantified and analysed for Cu, Pb and Zn. The pseudo-total and bioavailable contents of Cu, Pb and Zn and the enzymatic activities of beta-glucosidase, acid phosphatase, cellulase, protease and urease were determined in the soil mixtures. Two indirect acute bioassays with leachates from the soil (luminescent inhibition of Vibrio fischeri and Daphnia magna immobilization) were also used. The SS, in particular when in combination with SBS, corrected soil acidity, while increasing the total organic matter content and the cation exchange capacity. The application of SS led to a decrease in the level of effective bioavailable metals (extracted by 0.01 M CaCl(2), pH 5.7, without buffer), but caused an increase in their potential bioavailability (extracted by a solution of 0.5M NH(4)CH(3)COO, 0.5 M CH(3)COOH and 0.01 M EDTA, pH 4.7). Plant biomass increased more than 10 times in the presence of 100 Mg SS ha(-1), and more than five times with the combined use of 100 Mg SS ha(-1) and SBS, but a considerable phytotoxic effect was observed for the application rate of 200 Mg SS ha(-1). Copper, Pb and Zn concentrations in the shoots of L. multiflorum decreased significantly when using 100 Mg SS ha(-1) or SBS. The activities of beta-glucosidase, urease and protease increased with increasing SS applications rates, but cellulase had a reduced activity when using 200 Mg ha(-1)SS. Both amendments were able to suppress soil toxicity to levels that did not affect D. magna, but increased the soil leachate toxicity towards V. fischeri, especially with the application of 200 Mg SS ha(-1). This study showed that for this type of mine soils, and when using SS of similar composition, the maximum SS application rate should be 100 Mg ha(-1), and that liming the SS amended soil with SBS did not contribute to a further improvement in soil quality.  相似文献   

7.
Recent monitoring studies showed measurable levels of the 3,4-methylenedioxymethamphetamine (MDMA) in aquatic environments. However, no information is currently available on its potential hazard to aquatic non-target organisms. The aim of this study was to investigate the potential sub-lethal effects induced by 14-day exposures to low MDMA concentrations (0.05 and 0.5 μg/L) to zebra mussel (Dreissena polymorpha) specimens through the application of a biomarker suite. The trypan blue exclusion method and the neutral red retention assay (NRRA) were used to assess MDMA cytotoxicity. The activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione S-transferase (GST), as well as the lipid peroxidation (LPO) and protein carbonyl content (PCC), were measured as oxidative stress indexes. The single cell gel electrophoresis (SCGE) assay, the DNA diffusion assay, and the micronucleus test (MN test) were applied to investigate DNA damage, while filtration rate was measured as physiological parameter. Despite significant decrease in lysosome membrane stability, hemocyte viability and imbalances in CAT and GST activities pointed out at the end of the exposure to 0.5 μg/L, no significant variations for the other end points were noticed at both the treatments, suggesting that environmentally relevant MDMA concentrations did not induce deleterious effects to the zebra mussel.  相似文献   

8.
Organic compounds that can be thermally desorbed from airborne particles change cohesively with time, providing information about sources, photochemical transformations and transport of aerosols. In the spring of 1985, 138 airborne particulate samples were collected at an urban site in Boulder, Colorado. Samples were collected by drawing approximately 300 ℓ of air, for 58 min, through a small glass tube containing a quartz fiber filter. Particles were subsequently analyzed by direct thermal desorption of volatile organic compounds into a gas Chromatographic column followed by separation and detection of compounds with flame ionization or mass spectrometry. Factor analysis on the concentrations of 42 organic compounds in 138 1-h samples with time and meteorology revealed characteristic chromatograms for photochemical activity, biological sources and motor vehicle sources. Organic compounds desorbed from particles include terpenoids from biogenic sources, alkanes from vehicular and biological sources and aldehydes, ketones, carboxylic acids, lactones and furans from photochemical transformations and other sources. Concentrations of oxygenated species increased on sunny days relative to cloudy days or nights. Terpenoid concentrations increased when the wind direction was from a forested region west of the sampling site. Odd carbon number n-alkanes increased as temperature increased with the progression of springtime.  相似文献   

9.
Evidently increased environmental pollution as a consequence of the 25-year manufacture of polychlorinated biphenyls (PCBs) in eastern Slovakia was observed. PCB levels determined in ambient air, soil, surface water, bottom sediment, wildlife (fish and game) samples collected in a potentially contaminated area of about 250 km2 (a part of the Michalovce district) were compared with those determined in a control area (Stropkov district). Up to 1700 ng/m3 were found in ambient air in a village close to a manufacturer's dumping site and a highly contaminated manufacturer's effluent canal whereas PCB concentrations in ambient air samples taken in villages in the control area were about 80 ng/m3 only. While soil samples taken from the agricultural fields of the polluted area contained PCBs at levels comparable with soil samples from the control area (about 0.008 mg/kg) much higher values (from 0.4 to 53,000 mg/kg) were determined in soil taken in the vicinity of manufacturer's landfill and storage sites and especially plants preparing asphalted gravel using formerly PCBs in their heat-exchanging systems. The contamination of the Laborec river and large Zemplinska Sirava reservoir is caused by the manufacturer's effluent canal since PCB levels in the canal sediment are still to be found about 3000 mg/kg. While PCB levels in sediment samples from Michalovce watercourses ranged between 1.7 and 6 mg/kg, sediment samples from the control Stropkov district ranged between 0.007 and 0.052 mg/kg only. Fish living in contaminated Michalovce waters contained about hundred times higher PCB levels than those caught in Stropkov ones. Similarly, game animals shot in Michalovce forests contained several times higher levels than those shot in Stropkov ones.  相似文献   

10.
11.
The cockle Cerastoderma edule was exposed to sediments variously comprised of pulverised fuel ash (PFA) for two consecutive periods of 3 and 9 months. Chronic effects of PFA on this filter feeding bivalve were studied by examining changes in cellular and tissue pathology with the aid of a screening procedure developed for analysing histopathology conditional. The mortality rate was high, up 43% for the 100% PFA sediment and growth of the individual bivalves was low. The accumulation of metals appeared to be low at 1-10 times background tissue levels. Signs of cellular stress were seen in the digestive gland after the first 3 months. However, after 9 months, this same organ was in fairly good condition. Reproduction was delayed due to slow oocyte maturation.  相似文献   

12.
首次探索了一种破坏式造孔与有机复合相结合的新方法以制备介孔复合水环境净化材料,使最终产品成为一种具有广谱孔结构分布的复合环境材料。详细介绍了该方法的第二步工艺即添加剂升温烧蚀法,在优化后的最佳条件下,产品的孔径得到了进一步扩大,其中部分孔道直径可达至介孔级,同时材料的表面得到了进一步活化。经此步工艺后,所制备的中间产品染料吸附量是原材料的194倍,是酸洗刻蚀后产品的122倍;24h吸湿率是原材料的38倍,是酸洗刻蚀后产品的19倍。  相似文献   

13.
A statistical investigation of the connection between wind direction and wind speed and concentrations of airborne particulate matter at different places in Denmark is briefly described. The results show that the mean concentration levels over the whole country are highest in case of southerly to southeasterly winds. In general, the mean concentrations are decreasing with increasing wind speed for most wind directions, but in southeasterly winds the mean concentrations are higher for high wind speeds than for low wind speeds.  相似文献   

14.
Peter Gode 《Chemosphere》1984,13(8):933-938
The loss of chemicals in static fish tests due to biodegradation has been studied with eight model surfactants whose biodegradabilities in the OECD Screening Test range from 0 to 99 % BiAS removal. There was a good correlation between biodegradation in the fish test and in the OECD Screening Test. Only surfactants with a very high BiAS removal of above 93 % were also degraded quickly in the fish test. Surfactants with less than 80 % BiAS removal incurred losses of less than 20 % in the fish test. These results indicate that those substances which are not lost by volatility or adsorption will be maintained to at least 80 % of their nominal concentration during a 96 hour static fish test.  相似文献   

15.
An environmental risk assessment has been carried out for musk ketone and musk xylene according to the EU Technical Guidance Document for Environmental Risk Assessment for New and Existing Substances [1]. Musk ketone and musk xylene are used in fragrances for cosmetics and household products. For the fragrance industry these are important fragrance ingredients because of their excellent substantivity as well as for their unique smell, which determines largely the odor of a product.

The initial environmental risk assessment is based on information provided by the fragrance industry as represented in the Netherlands by its association NEA, by the Research Institute for Fragrance Materials (RIFM) and data reported in the international open literature. The risk assessment includes an evaluation of the risks for aquatic organisms in surface water and sediment and for soil organisms in soil after application of sewage sludge. Secondary poisoning of fish-eating birds and mammals is considered as well. For each compartment the Predicted Environmental Concentration (PEC) is compared to the Predicted No Effect Concentration (PNEC) to obtain PEC/PNEC ratios. Since monitoring data are available in water, sediment and fish, similar ratios are obtained with measured concentrations instead of the predicted ones.

For both substances, PEC/PNEC ratios are at or below 0.1 for organisms in the aquatic environment, including sediment organisms. PEC/PNEC ratios for fish-eating predators are 0.01. Ratios based on monitoring data are below 0.01 for all of these organisms. For soil organisms the PEC/PNEC ratio is 0.5 for musk ketone and 1.3 for musk xylene. Although in the Netherlands (as well as in some other European countries), sewage sludge presently finds no application as fertilizer on agricultural soil, the aim of environmental policy is to upgrade the sludge quality to enable future applications on agricultural and grassland. The reliability of the predicted soil concentrations can be greatly improved by obtaining experimental data on fate and behaviour of musk ketone and musk xylene in digested sludge and soil.

The risk assessment provides reassurance for the aquatic compartment while pointing the way for obtaining aditional data for the soil compartment.  相似文献   


16.
Under aquarium conditions, treatment with the herbicide paraquat (PQ) and with the insecticide methidation (MD) caused cell damage and stress in carp (Cyprinus carpio L.), as shown by increases in glutamate-dehydrogenase (GIDH, EC 1.4.1.2), glutamate-oxalacetate transaminase (GOT, EC 2.6.1.1) and lactate dehydrogenase (LDH, EC 1.1.1.27) activities and in blood sugar levels. PQ proved synergistic with MD in certain cases as regards the harmful effect exerted. On combined treatment, dilated extracellular spaces were visible by light microscope in the liver, while electronmicroscopic studies revealed signs indicative of cell autolysis in the same organ.  相似文献   

17.
The aim of this paper is to develop the technique for mapping the air pollution in cities using measured and computed concentrations. It is based on the combined use of deterministic and stochastic modelling. Two different approaches are applied to extrapolate the measurements to the regular grid points covering the city. The first uses the method of the principal components, and the second is based on optimal interpolation or 'kriging' of meteorological fields. The results of the application of this model for the mapping of air pollution in the city of Pskov, Russia, are given.  相似文献   

18.
西湖北里湖沉积物磷形态分布及其与间隙水磷的关系   总被引:1,自引:0,他引:1  
杭州西湖是典型的富营养化浅水湖泊。经过环湖截污等工程措施,影响西湖的外污染源得到有效的治理,但西湖仍处于富营养化状态。在外污染源得到控制后,富含营养盐的沉积物成为西湖水质改善的主要限制因子。通过研究西湖北里湖沉积物中磷的赋存形态和丰度、间隙水磷含量垂向时空分布特征,分析沉积物磷形态与间隙水磷含量的相关性,探讨内源磷对西湖北里湖营养盐的贡献作用。结果表明,北里湖沉积物中活性磷含量较低,不同磷形态及其含量在垂向上呈现一定的波动,没有表现出明显的规律。间隙水总可溶性磷(TDP)和PO34-含量随沉积物深度的变化不明显,但其含量总体在垂向上都有先升高后降低的趋势,与沉积物中各形态磷均具有一定的正相关性。因此,沉积物磷对水体富营养化具有一定的贡献。  相似文献   

19.
针对垃圾渗滤液膜浓缩液中有机物成分复杂、难以降解的特点,采用UV-Fenton催化氧化+EM菌(有效微生物菌群)高效生物脱氮组合工艺开展连续120 d的中试实验,考察了组合工艺中各处理单元对浓缩液中COD、TN和NH3-N的去除效果。结果表明,组合工艺运行稳定,对COD、TN和NH3-N的去除率分别达到95.2%、90%和95%,出水各项指标均能满足《生活垃圾填埋场污染控制标准》(GB 16889-2008)排放要求。结合紫外可见光谱、三维激发-发射光谱和气相色谱-质谱实验结果,UV-Fenton催化氧化可使浓缩液中含有共轭键有机物的芳香结构在较大程度上被破坏,分子质量聚合度大幅降低,从而将腐殖质以及可见光区富里酸等难降解的大分子有机物降解为小分子,从而提高可生化性。后续的EM菌高效生物脱氮单元基于硝化反硝化,可以进一步高效去除NH3-N和TN。  相似文献   

20.
通过对宿迁市近两年来的环境质量综合指数现状及原因分析,结合“十一五”的社会经济发展规划,指出了提高宿迁环境质量综合指数存在的压力及原因,并提出了对策及建议。  相似文献   

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