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1.
Phthalate esters have been extracted from water, sediment and biota samples using a single solvent system, dichloromethane, and clean up by alumina column chromato-graphy. Analysis for dimethyl, diethyl, di-iso-butyl, di-n-butyl, di-n-heptyl, di-(2-ethylhexyl) and di-n-nonyl phthalates was carried out by gas chromatography and mass spectrometry. Phthalate esters were quantified using multiple ion detection, focussed on m/z 163 and m/z 149.

The procedure was tested on samples of water, sediment, bivalves and fish from the estuary of the River Crouch. The method gave satisfactory sensitivity for the determination of phthalate ester levels above the commonly found blank values of 1 to 20 nanograms per gram of solid or litre of water.

Comparative samples of fish from the heavily industrialised Tees Bay area did not show greatly elevated levels of phthalate esters.  相似文献   

2.
邻苯二甲酸酯类(PAEs)增塑剂被普遍用于塑料制品中,在大气、水等环境中广泛存在,其潜在危害受到关注。水环境中的PAEs,从藻类等初级生产者吸收,到浮游动物、游泳动物等通过鳃和皮肤直接接触或捕食摄取,在水生生物之间转化和传递。笔者总结了PAEs在水生食物链中不同营养级生物体的含量,分析了PAEs在食物链中富集和转化的影响因素(辛醇-水分配系数Kow、代谢转化、生长阶段等)。目前的研究表明PAEs可能在食物链中传递,最终在较高营养级生物体中富集。同时总结了5种PAEs(邻苯二甲酸二丁酯、邻苯二甲酸二乙酯、邻苯二甲酯丁苄酯、邻苯二甲酸二(2-乙基)己酯和邻苯二甲酸二甲酯)对水生生物的毒性效应的研究进展,已有研究表明PAEs对藻类的细胞器和抗氧化体系,对鱼类的生殖系统、内分泌系统和抗氧化体系都有一定程度损伤。PAEs在食物链中传递和富集现象的存在会对高营养级水生生物产生潜在危害。针对目前PAEs在食物链中传递的研究数量较少、结构简单等问题,对未来研究方向做了简要分析和展望。  相似文献   

3.
A new material with high content of fly ash named 'Ashcrete' has been developed. to examine the applicability of Ashcrete to marine structures, strength characteristics, resistance to sea water attack, and safety in the marine environment have been studied. the following results have been obtained:

1) the strength characteristics of high-volume fly ash concrete depend upon the type and proportions of chemical activators as well as curing conditions.

2) Ashcrete using sodium chloride (NaCI) as a chemical activator shows high initial strength and good strength development with age.

3) Ashcrete containing NaCI activator shows good resistance to sea water from the viewpoint of its strength characteristics, volume changes and microstructurcs.

4) Since 1980 many types of large-scale artificial reefs made of Ashcrete have been installed in the sea. As a result of long-term studies and underwater observations, the Japanese Government has demonstrated the durability of the material, safety in the marine environment and attractiveness to fish.

5) It is therefore proposed that Ashcrete might be used in constructing large-scale sea mounts in deep water for the purpose of generating upwelling.  相似文献   

4.
Lake Edku is one of the Nile Delta shallow brackish water coastal lagoons with communications with the southeastern Mediterranean.

Sediment samples were recovered from the top 10 cm of the lake bottom to study principally their total, inorganic and organic phosphorus. Related sediment parameters such as particle size, organic carbon, carbonate and iron contents were also studied in detail.

It is shown that the lake sediments are generally a sand-silt-clay mud enriched with carbonate (11.4-42%), organic carbon (0.9-11.4%) and iron (1.6-5.6%).

The total phosphorus content in these sediments is 503-1329 μg/g, inorganic phosphorus, 468-954 μg/g and organic phosphorus, 35-526 μg/g.  相似文献   

5.
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   

6.
Phthalate esters in the topsoil samples collected from Beijing were determined by derivatization and gas chromatography–mass spectrometry techniques. The results showed that diethyl phthalate (DEP), diisobutyl phthalate ester (DIBP), dibutyl phthalate ester (DBP), dibutyl (2-ethyl hexyl) phthalate (DEHP), and dimethyl phthalate (DMP) were found in the topsoils. The total concentrations of the five phthalate esters varied from 2.30 to 24.71 μg g?1. According to phthalate esters (PAEs) control standards in soil of the USA, the standard exceeding rates of DMP, DBP, and DEHP were 100 %, 100 %, and 4.84 % in soils of Beijing, respectively. The rate of DBP exceeding soil remediation standard was 12.9 %. Overall, concentrations of PAEs in Beijing were at a high level in China. The concentrations of DBP, DEHP, and DIBP were high, and the total concentrations of all the phthalate esters were higher in the areas with intensive human activities than in the other areas, which may be related to the use of phthalate compounds (such as the use of plastic products). The total and individual concentrations of phthalate compounds were relatively low in the areas that used plastic films compared with other samples due to the diffusion of atmospheric motion, categories, and amounts of plastic products and other factors. The greatest contributor may be the usage amount of plastic products in people’s daily lives.  相似文献   

7.
In recent years there has been an increase in the intensity and frequency of environmental monitoring surveys at UK sewage sludge disposal sites. These have been carried out by the regulatory authorities and by the licensees. in order to ensure maximum efficiency, a coordinated and harmonised programme of monitoring has been developed. the programme concentrates on sediment chemical and biological quality but also includes assessments of water and fish quality

In England and Wales the Ministry of Agriculture, Fisheries and Food is the regulatory authority and the Water Authorities are the licensees. the Ministry's first priority is the collection of samples for temporal trend analysis but in addition, infrequent surveys are made to check the status of the disposal site and surrounding areas. in the periods between status surveys, regular spatial surveys designed to define the area of impact are carried out by the Water Authorities.  相似文献   

8.
At the start of the Loch Fleet Project in 1984, the Loch and the upper 7 km of its efferent stream were found to be devoid of trout (Salmo trutta) as a result of acidification. Following the liming treatments applied to the catchment, from 1986 the formerly toxic water quality conditions (pH ∼ 4.5, calcium ∼ 1 mgl-1, elevated aluminium and heavy metal levels) were eliminated, and trout were reintroduced on two occasions, in 1987 and 1988. A total of 520 fish were stocked, at a combined density equivalent to 5.5 kg ha-1. Surveys of the loch and stream populations were carried out annually until 1993 to monitor their development, using a range of techniques, including electrofishing, gill-netting, seine-netting, spawner trapping and mark-release recapture methods. Length and scale- analysis were used to investigate fish growth.

The trout population in Loch Fleet expanded rapidly as a result of natural spawning in the loch's main feeder stream, augmented by the use of an artificial spawning bed which was constructed at the loch outlet in 1990. in mid-1983 the stock density, estimated by mark-recapture census methods, had increased to 24.9 kg ha-1. Poor recruitment in the years 1991-93, however, reduced the rate of expansion and resulted in a population comprising mainly older individuals. the poor recruitment in these years was not fully explained but was not caused by water quality and was most likely a result of fry washout by spring spates.

Fish growth rates were high initially and were estimated on the basis of the Elliott trout growth model to be optimal for the prevailing water temperature regime of the loch. By 1991, growth rates had fallen, probably as a result of competition for food, but showed signs of recovery towards the end of the study period in 1993, following the period of lower population densities of young fish.

Trout rapidly repopulated the loch's outlet stream after 1987 but have remained sparse and have shown no signs of spawning within most of the stream. Water analyses have shown that the liming of the Loch Fleet catchment has minimal impact on downstream waters when flows are high, so that potentially toxic acid episodes have not been prevented.  相似文献   

9.
Sea urchins (Paracentrotus lividus) were collected from the Mediterranean coast off Alexandria, Egypt and the Atlantic coast of Ireland to the west of Galway. Samples of another urchin species, Psammechinus miliaris, were collected from the entrance to Southampton Water, U.K. Both the Alexandria coast and Southampton Water receive domestic and industrial waste water inputs whilst the western Irish coast is relatively unpolluted.

Sampled animals were dissected to separate coelomic fluids, Aristotle's lantern, gonads and tissue (digestive tract plus connective tissue). the concentrations of heavy metals (cadmium, copper, lead, nickel and zinc) in the different parts were measured using flame atomic absorption spectroscopy.

Many levels of heavy metals in the different parts were similar in specimens taken across the wide range of sites and the two species. A notable exception was the high level of copper (33 μg g-1 dry wt.) and zinc 328 μg g-1- dry wt.) in urchin tissue from Southampton Water.

The metal concentrations in the gonads of Paracentrotus lividus are of particular interest because of human consumption of this species. the highest levels of copper (3.3-5.2 g-1- dry wt.) and zinc (74-181 μ g-1- dry wt.) dry wt.) in gonads were found in the samples from Egypt. Data from this study are compared with other results reported from the Mediterranean.

A simple, short term, elevated water column copper uptake experiment was undertaken with Paracentrotus lividus which showed an increase in gonad concentrations of this element.  相似文献   

10.
Waste tyres pose a major disposal problem on land creating a fire hazard and, in warmer climates, providing breeding pools for mosquitoes. the void space in tyres makes them unsuitable for land burial. Schemes to use shredded tyres for road bases and asphalt filler are being pursued in the USA. Tyre combustion for electricity production is being investigated in the UK.

The widespread availability and durability of tyres has led to their use in the marine environment for breakwaters/coastal defence structures and as artificial reefs for promoting fisheries.

Tyres have a low density and have been used in floating breakwaters. Schemes have been proposed to protect and strengthen shorelines with tyre structures.

The void space in tyres facilitates the construction of artificial reefs to attract fish. the most intensive use is in the south west Pacific and Australia. Tyre surfaces are colonised by algae and a wide range of faunal species, including corals and shellfish. the wide acceptance of tyres as a suitable reef construction material appears to be based largely on these observations. Experience of initial poor deployment practices in the USA led to tyres washing ashore after storms and resulted in the banning or restriction of their use in coastal states of the USA. A review of the scientific literature has yielded limited information on the environmental impact of tyres and in particular the leaching of heavy metals and organic compounds from tyres into sea water.

Preliminary results of tyre dust/sea water leaching studies are presented. These identify zinc as the major leachate (totalling 10mg/tyre after 3 months). Diluted leachates have not shown significant effects of the growth of the phytoplankton Phaeodactylum and Isocrysis.

Further work to characterise the sea water leaching of tyre compounds is recommended.  相似文献   

11.
The Axios (Vardar) River originates from the south west part of Yugoslavia, transverses Greece, and discharges into the Thermaikos bay in the north Aegean Sea.

The proton induced X-ray emission (PIXE) method with external beam was used for the elemental analysis of water and sediment samples, while measurements of water temperature, dissolved oxygen content, conductivity, pH, and the water flow were made in situ. Water samples were also analysed for total phosphates, nitrates, chlorophyll, and BOD. The data collected for a 16-month period indicate that the Axios River is polluted as far as the metal content is concerned; its primary productivity is low and it is slightly enriched during its course into the Greek territory.  相似文献   

12.
Trace metals (Cd, Cr, Cu, Mn, Pb and Zn) and Fe were analyzed in two sediment reference samples (NBS 1646, MESS-1) with AAS fitted with graphite furnace, using five different (three total and two selective) extraction procedures.

The comparison of the total digestion methods (hot strong acids) with reference materials gave good results for almost all of them, and the “teflon bomb” was preferred for its rapidity and ease of operation. Some non-referenced data on total and organic carbon, total nitrogen and minerals are given. The two selective leaching extractions (nitric and cold hydrochloric) were also compared with reference values.

The use of certified reference materials (CRM) for environmental chemistry is recommended, together with the determination of organic matter and fundamental mineralogical composition.  相似文献   

13.
25 food samples, 5 mother’s milk specimens, 4 dust samples, and 16 textiles were analysed for phthalic acid esters. Phthalic acid esters were detected in all samples, with di (2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DBP) being the most abundant phthalates. Raw milk samples revealed average concentrations of total phthalate of 0.1 mg/kg. Retail milk did not contain higher loads than raw milk, even storing samples until their “best-before” date did not result in elevated levels. Skimmed milk was less contaminated than whole milk. The higher concentrations of DEHP and total phthalates in cream samples are due to their higher fat content. With concentrations up to 1.54 mg/kg, ground hazelnuts, almonds, and nutmeg in plastic packagings showed relatively high levels. In infant food, only traces of DEHP and DBP could be found while other phthalic acid esters were not detectable. The mother’s milk samples also exhibited only low amounts of approx. 0.1 mg/kg, thus indicating that there is no accumulation of phthalate esters in the human body. Extraordinarily high concentrations were found in dust samples; with the levels ranging from 300 to 5370 mg/kg and DEHP being the major compound. This leads to the conclusion that the air path must play a considerable role in the transfer of phthalic acid esters. As dust contains considerable amounts of textile fibres, textiles were also included in the investigation. The phthalic ester levels in the textile samples ranged from 3.42 to 34.44 mg/kg. Therefore, the high phthalate contaminations of dust cannot be explained by textile fibres.  相似文献   

14.
The near shore coastal and marine environment of several Caribbean islands is their most biologically productive and economically important zone. However, almost all landbased activities possess the real potential of degrading the quality of near shore waters and ultimately diminishing the utility of the marine resource. This condition is largely attributed to the individual smallness of the islands and their geographic proximity to each other.

Available sanitary water quality data from across the region indicated that while recreational areas are in general safe for water contact activities, bacterial densities in excess of several international criteria are consistently recorded in harbours. Organochlorine pesticide residues were generally in the 5 ng l-1 range in unfiltered sea water but were significantly higher (1-100) ng g-1 in limited samples of sediment and biota. Additional data requirements to gain further insight into the current state of the Caribbean environment are also identified.

A summary of the major land based sources of marine pollution (including sewage, industrial effluents and agricultural run-off) in the insular Caribbean is presented.  相似文献   

15.
氟乐灵对土壤微生物和蚯蚓的影响   总被引:1,自引:0,他引:1  
本文探讨了除草剂氟乐灵对土壤微生物的影响。结果表明:低浓度的氟乐灵对土壤细菌、放线菌和霉菌的生长有刺激作用,不仅数量增加,而且菌落明显增大,但对微生物种无明显选择性;氟乐灵能促进大豆根瘤菌和圆褐固氮菌的生长;在培养液中同时加入氟乐灵和圆褐固氮菌,可抑制固氮菌的乙炔还原活性;在生长良好的固氮菌培养液中,再加入氟乐灵,可明显刺激固氮菌的乙炔还原活性;土壤微生物可以氟乐灵为唯一碳源和氮源,加速氟乐灵降解;2.0ppm以上浓度的氟乐灵对蚯蚓有毒害作用。  相似文献   

16.
The aim of this study is to estimate the distribution of heavy metals in water and in suspended particulates in relation to the observations made on hydrology, concentrations of oxygen, nutrients and chlorophylls in different coastal areas of the Ligurian Sea.

The superficial water samples were collected during the cruise of the R/V “Bannock” in 25 stations placed at different distances from the coast at Alassio, Savona, Genova, Chiavari and Corniglia (between 0.5 and 6.1 nautical miles from the coast). Furthermore water samples were collected at a depth of 10, 20, 30, 50, 75 and 100m, on offshore stations of every transect.  相似文献   

17.
Dissolved Cu, Fe and Ni were determined in sea water samples from 9 stations in the Ligurian Sea located along the two traverses Imperia-Capo Corso and Nice-Calvi and at depths between 0 and 200 m. The samples were preconcentrated from small volumes of sea water by complexation with ammonium pyrrolidine-dithiocarbammate (APDC), extraction with CCl4 and determination by AAS with electrothermal atomisation. The geographical distribution shows that in the central part of the inner traverse there is a maximum of Cu and Fe concentration; the vertical distribution shows no significant depletion of the dissolved elements in the epithalassa.

The results allow for a first approach to the more general problem of the distribution of the trace elements in the Ligurian Sea.  相似文献   

18.
UV-fluorescence spectroscopy method with synchronous mode of scanning was used to characterize the types of aromatic hydrocarbons in surface sediments. the sampling stations were located on two transverses between Yugoslavian and the Italian coasts in the middle of the Adriatic Sea. the preparation of sediment samples was made according to IOC/UNESCO (1982). Synchronous excitation/emission scanning were done at wavelengths from 236/260 to 516/540 nm. Since the wavelength of maximum emission is a function of fused aromatic rings in a molecule, the fluorescence spectra of each sample were divided into three intervals: 300-340, 340-400, over 400 nm, corresponding to compounds with 2, 3 and 4,5 and more rings respectively.

Large qualitative differences were established between sediment samples. PAH with 5 and more rings are more prevalent near the Italian coast.  相似文献   

19.
Estrogenic Effects of Effluents from Sewage Treatment Works   总被引:39,自引:0,他引:39  
The occurrence of hermaphrodite fish in the lagoons of sewage treatment works led us to hypothesize that sewage effluent might contain a substance, or substances, estrogenic to fish. to test this hypothesis, we placed cages containing rainbow trout in the effluent from sewage-treatment works, and one to three weeks later measured the vitellogenin concentration in the plasma of the fish. Vitellogenin is a protein synthesized by the liver of oviparous fish in response to estradiol stimulation; it is then conveyed by the blood to the ovary, where it is sequestered by oocytes to form the yolk. Thus, the presence of vitellogenin in the plasma is indicative of estrogenic stimulation of the liver. an initial study, at a sewage-treatment works, showed that plasma vitellogenin concentrations rose rapidly and very markedly (over 1000-fold in three weeks) when trout were maintained in the effluent. an extensive nationwide survey was then conducted. Results were obtained from fifteen sewage-treatment works distributed throughout England. in all cases, exposure of trout to effluent resulted in a very pronounced increase (500 to 100,000-fold, depending on site) in the plasma vitellogenin concentration. Induction of vitellogenesis was also observed in carp, but to a much lesser extent than in trout.

The identity of the estrogenic substance is unknown. It is suggested that the two most likely possibilities are ethynylestradiol, originating from pharmaceutical use, or alkylphenol-ethoxylates (APE), originating from the biodegradation of surfactants and detergents during sewage treatment.

Laboratory studies on the potency of ethynylestradiol demonstrated that levels as low as 1 to 10 ng 1-1 could generate the response shown by the caged fish and that positive responses may arise at 0.1 to 0.5 ng 1-1. Further work is in progress on the potency of APE.  相似文献   

20.
The effects of nitrate additions on the physics, chemistry and biology of lake water were studied in 5 × 10 m polyethylene enclosures installed in Lake Kastoria, a shallow eutrophic lake in Northern Greece. The water physics, chemistry, chlorophyll a and nitrogenase activity were monitored from July 10 till October 17 1985 at 2 week intervals. The experiment included a control enclosure.

Water confinement in the control enclosure resulted in ammonia accumulation, a slight decrease in chlorophyll a, a significant reduction of nitrogenase activity and an increase in phosphorus release from the sediments at the end of the experimental period.

The addition of KNO3 resulted in higher than the control accumulation of NH3, chlorophyll reduction, increase in water transparency and reduction of nitrogenase activity. Large losses of nitrogen added were measured which were attributed to denitrification, organic matter sedimentation and ammonia volatilization. Anaerobic but not aerobic phosphorus release from sediments was inhibited at the end of the period. The reduction of nitrogenase activity and of chlorophyll a concentration are attributed to changes in phytoplankton composition from blue-greens to small-sized species grazed by zooplankters.  相似文献   

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