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The concentrations of fifteen PAH compounds in samples of sediment and blue mussel tissue (Mytilus trossulus) were measured. In addition, the biliary polycyclic aromatic hydrocarbon metabolites present in flounder (Platichthys flesus) were analysed. Two methods were used in the analysis of PAH metabolites; high performance liquid chromatography (HPLC) and fixed wavelength fluorescence (FF). The major PAH metabolite which could be measured using the HPLC method was 1-OH pyrene. It was possible to detect 1-OH Phe and 3-OH B[a]P in 70 and 24 samples respectively, of the 87 samples analysed. However, the concentrations of 1-OH Phe and 3-OH B[a]P were below or near to the LOQ (0.002 μg ml(-1) bile). The bile of flounder samples from the Gulf of Gdańsk had 1-OH Pyr concentrations which ranged from 0.019 to 0.066 μg ml(-1) bile. The high linear correlation observed between the quantity of 1-OH pyrene determined by the HPLC-F method and the content of the sum of pyrene-type PAHs obtained by the FF method indicated the FF method of determination of pyrene-type PAH metabolites can be used as a screening method. The content of ∑(15)PAHs in sediments collected in the Gulf of Gdansk, in 2008, ranged from 29.3 to 103 μg kg(-1) dw. In mussel tissue ∑(15)PAHs concentrations were between 173.2 μg kg(-1) dw and 237.7 μg kg(-1) dw. All concentrations measured in the current study, in mussel tissue, were below the OSPAR toxicity threshold values.  相似文献   

3.
Using existing monitoring data, the present study attempts to characterize spatial patterns of surface water nutrients in the Baltic Sea. The analysis was made for two different spatial scales, differences between and within sub-basins.Non-parametric methods were chosen to reduce problems with the distributional properties of the data. By dividing the data into four seasons care was taken as to seasonality. To avoid bias due to different laboratory analysis, only data from Nordic countries were used, whose results did not apparently depart from each other. Bias due to different sampling frequency was another problem. This was reduced by using only the last observation in each season for every station and year.The results suggested differences in the nutrient concentrations between basins. The two northernmost basins (Bothnian Bay and Bothnian Sea) had lower phosphate concentrations and higher silicate concentrations compared to the rest of the Sea. Bothnian Bay and the Gulf of Finland had higher nitrate concentrations.The concentration structure within basins was studied using transects in both latitudinal and longitudinal direction. A gradient for phosphate and nitrate was found in the Gulf of Finland, with lower concentrations at the mouth. The Bothnian Sea showed lower concentrations in the middle of the basin compared to the coasts. The highest concentrations of phosphate were found close to the Finnish coast and for silicate the highest concentrations were located near the Swedish coast. It was not possible to study variation in the west-east direction within the Baltic proper, due to data shortage. For the transects in the north-south direction no differences were detected for nitrate and silicate. Phosphate gave one significant result during autumn for the transect in the eastern part of the Baltic proper.This study revealed several problems associated with the data available. Uneven sampling in space and time put severe constraints on the study. A better design of the monitoring program is suggested, where spatial properties are considered explicitly. Revision of the program in this direction is needed for reasonable calculation of total amounts and concentrations representative for a basin.  相似文献   

4.
The Baltic Sea runoff events during 1970–2000 were analysed with non-linear estimation in order to find potential stability and time-varying (non-constancy) properties of time series parameters. In the Baltic Sea area, the wintertime rainfall is expected to increase, especially in the northern parts of the watershed; furthermore, seasonality is expected to decrease, i.e. the runoffs will become more evenly distributed over seasons, mainly by decreasing springtime peaks. We found a general increase in runoffs over the time period studied that consisted of a level shift upwards during the early 1980s. The runoffs considerably resulted from inputs in the months of April to June (which points to the significance of winter precipitation) and are biased to northern parts of the catchment. Our results suggest that this is connected with snow and ice melting in the northern areas of the watershed, especially in the subarctic catchment area of the Neva River (the area includes, for example, three of the four biggest lakes in Europe, Lake Ladoga, Lake Onega and Lake Saimaa, which are annually covered by ice). The yearly variation in runoff is significantly stabilised by large N–S extension of the watersheds of these lakes. The results are generally in accordance with the presented climatic expectations; however, decreasing seasonality was not obvious in the series yet. However, we found potential implications of system change towards decreased seasonality. By better understanding of ongoing processes in the sea, the results can give us an opportunity to better evaluate the system control, predicted areal consequences and ecosystem effects of the climate change. The analysis proved to be a sensitive tool for studying climatic variation in a relatively small area and over a short time span.  相似文献   

5.
Ambient particles vary greatly in their ability to affect visibility, climate and human health. The fine fraction of aerosol is responsible for greater and wider effects on human health; thus, investigation of this fraction is very important. Continuous measurements of PM2.5 (particulate matter below 2.5 μm in size) concentrations at the Preila monitoring station started in 2003. During a period of 2 years, the episodes of high daily and semi-hourly concentrations of PM2.5 were measured. These episodes did not depend on the season or time of day. The substantial role of long-range transport of pollutants to these increases in concentration was shown using chemical and statistical analysis. It was found that most of the severe episodes occurred when air masses came from a specific site besides it was established that air masses of different origin were characterized by different mixing layer depth. Lower mixing depth was observed in air masses characterized by higher observed concentrations at the measuring site and vice versa. PM2.5 concentrations showed diurnal and seasonal variations whose pattern reflected the regional origin of the aerosol. The regional pollution level was evaluated by the statistical analysis of PM2.5 concentrations. The background annual average of PM2.5 mass concentration for the eastern coast of the Baltic Sea was 15.1 ± 0.8 μg m−3.  相似文献   

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Environmental genotoxicity and cytotoxicity effects in the gills of mussels Mytilus edulis, from the Baltic Sea areas close to the Būtingė oil terminal (Lithuania) before and after accidental oil spill in 31 January 2008 were studied. Mussels from the oil spillage zones were collected in 12 days, in 3 and 6 months after the spill to determine the effects of the spill. Mussels sampled in 2006–2007 were used for the assessment of the background levels of genotoxicity and cytotoxicity in the Būtingė oil terminal area. Comparison of the responses in M. edulis before and after the oil spill revealed significant elevation of frequencies of micronuclei (MN), nuclear buds (NB) and fragmented-apoptotic (FA) cells. Environmental genotoxicity and cytotoxicity levels in mussels from the Palanga site before the accident (in June 2007) served as a reference. Six months after the accident, in July 2008, 5.6-fold increase of MN, 2.9-fold elevation of NB, and 8.8-fold elevation of FA cells were observed in mussels from the same site.  相似文献   

8.
Impact of thermal discharge from a coastal power station (Madras Atomic Power Station, southeast coast of India) on the spatial variability of Donax cuneatus abundance was assessed to determine the impact boundary. Totally, 20 sites were selected both on south and north side in increasing spatial scale from mixing zone, 12 locations were selected toward south side at a distance from 0 (near mixing point) to 2,000 m and eight location were selected toward north from the effluent mixing zone. Mean water temperature along the coast ranged from 29.1 ±0.15°C to 31.2 ± 0.15°C. Total organic carbon content in the sediment ranged from 0.27% to 0.70%. D. cuneatus population on the swash zone was ranged between 1.3 ± 1.5 and 88.3 ± 9.6 m???2. Meager population of wedge clam was observed up to 100 m (S100) south from mixing point and abundance gradually increased in different spatial scale. Comparatively high abundance was observed from S400 and reached maximum at S1000 (64.0 ± 3.6 m???2). Similar pattern was observed on north side too but less abundance was observed only up to 80 m (N80). Maximum abundance was observed at control location C3-N500 (88.3 ± 9.6 m???2). Forty meters on either side of discharge point was highly impacted, 80 to 100 m toward plume flow (south) was moderately impacted, and 80 m north of mixing point also witnessed moderate impact. After 100 m (N100), north was not affected by effluents, whereas between 100 and 400 m, south was influenced slightly. Multivariate clustering pattern on the environmental variables of all sampling locations and population trend of D. cuneatus at those stations showed similarity. Present investigation unambiguously showed that the abundance pattern of D. cuneatus on the sandy beach of east coast of Kalpakkam is not governed by single major factor but due to the result of multiple interacting factors. The population size of the wedge clam with reference to the effect of power plant effluents and other features of habitats of the beach ecosystem are also discussed.  相似文献   

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An ongoing biomonitoring program using oysters (Crassostrea virginica) was implemented in 1978 to monitor radionuclide releases from the Calvert Cliffs Nuclear Power Plant located on Chesapeake Bay. The program involves quarterly removal and replenishment of oysters located in a tray about 0.2 km from the effluent discharge. Radiosilver (Ag-110m) concentrations in tray oysters (pCi/kg ww) were analyzed using ANCOVA-like models with plant releases of Ag-110m in the present and immediately preceding quarters and season of exposure as explanatory variables. Hypothesis testing based on the estimated models and comparison among model predictions under hypothetical release scenarios showed that season of exposure was important in influencing Ag-110m concentrations, with exposure during the Fall and Summer seasons resulting in significantly higher Ag-110m concentrations in tray oysters than exposure during the Winter and Spring seasons. From a management perspective of minimizing Ag-110m concentrations in oysters located near the plant, Winter and Spring are the preferred seasons for plant releases.  相似文献   

11.
Using the reproductive capacity of fish appears to be a suitable approach for risk assessment in the aquatic environment since fish are a typical representative thereof and in addition they are of considerable societal value. Generally the early embryonic stages are considered to be one of the most sensitive parts of a fish's life cycle. A method has been developed to use the state of health of live, naturally spawned fish embryos from plankton samples for biological effects monitoring. During the years 1985–1987 in the southern North Sea and in 1991–1992 in the whole of the North Sea fish eggs were sampled from surface waters and examined for developmental abnormalities. Elevated embryo malformation rates were detected in the plume of the major rivers Elbe and Rhine as well as along the eastern coast of England. Occurring malformations are thought to be pollution-related and may be used to define areas of environmental deterioration. The method is discussed in view of its suitability for biological effects monitoring using malformations in fish embryos as biomarkers.  相似文献   

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The purpose of the current study was to investigate spatial and seasonal variation of dioxin and dioxin-like PCB (dl-PCB) content in herring sampled along the northern Baltic Sea coast and map out risk zones for dioxins and dl-PCBs. We further aimed to investigate relationships between congener distribution (pattern) and sampling location and season. The results showed that there were distinct geographical differences in concentrations of dioxins, dibenzofurans and dl-PCBs along the Swedish coast, from the Bothnian Bay to north Baltic Proper, with the highest levels detected in the southern Bothnian Sea. The majority of the locations showed concentrations above the prescribed maximum for dioxin residues (4 TEQ pg g(-1) wet weight [w.w.]). If all the edible parts of the fish (muscle, subcutaneous fat and skin) are considered, the estimated concentrations exceeded the prescribed maximum level in the whole study area for herring collected during spring-summer. Concentrations in herring caught during spring-summer compared to concentrations in herring sampled in the autumn indicated seasonal variation. The pattern analysis showed a variation in relative congener concentration at the different sampling locations (spring-summer). Pattern differences were also noticed between seasons.  相似文献   

14.
Environmental Modeling & Assessment - To build a forecasting tool for the state of eutrophication in the Archipelago Sea, we fitted a Generalized Additive Mixed Model (GAMM) to marine...  相似文献   

15.
This paper presents and discusses the levels and temporal trends of concentrations of Cd, Pb, Hg, Cu, Zn, and As in livers and Hg in the muscle tissues of cod (Gadus morhua L) from the Baltic Sea during the period 1994–2010. Concentrations of Pb, Hg, and Cd exhibited significant downward trends. Cu and Zn concentrations exhibited upward trends in the period 1994 to 2010. No trends were detected for concentrations of As. The temporal trends identified in heavy metal concentrations in cod livers corresponded to the directions of changes in concentrations of these elements introduced into the Baltic Sea via river runoff and atmospheric emission, and those in surface and deep waters of the Baltic. Downward trends in the concentrations of toxic metals in cod livers suggest that advantageous changes are occurring in concentrations of heavy metals in the environment of the southern Baltic Sea.  相似文献   

16.
Red tide of dinoflagellate was observed in brackish water fish ponds of Terengganu along the coast of the South China Sea during the study period between January 1992 to December 1992. The nearby coastal moat water facing the South China Sea is the source of water for fish pond culture activities of sea bass during the study period. An examination of water quality in fish ponds during the study period indicated that both the organic nutrients were high during the pre-wet monsoon period. The source of the nutrients in coastal water was believed to be derived from the agro-based industrial effluents, fertilizers from paddy fields and untreated animal wastes. This coincided with the peak production of dinoflagellate in the water column in October 1992. The cell count ranges from 8.3 to 60.4×10.4×104/l during the bloom peak period and the bloom species were compared entirely of non-toxic dinoflagellates with Protoperidinium quinquecorne occurring >90% of the total cell count. However, both cultured and indigenous fish species were seen to suffer from oxygen asphyxiation (suffocation due to lack of oxygen). The bloom lasted for a short period (4–5 days) with a massive cell collapse from subsurface to bottom water on the sixth day. The productivity values ranged from 5–25 C g/ l / h with a subsurface maximum value in October 1992. Two species of Ciliophora, Tintinnopsis and Favella, were observed to graze on these dinoflagellates at the end of the bloom period.  相似文献   

17.
In the present study the spatial and the vertical distributions of 210Pb were investigated in the soils around a uranifereous coal fired power plant (CPP) in Yatagan Basin, in Western Turkey. The variation of 226Ra activity along the soil profiles was studied to assess the unsupported 210Pb distribution in the same samples. 226Ra was measured by gamma spectroscopy and 210Pb activities were determined from 210Po activities using radiochemical deposition and alpha spectroscopy. The total 210Pb activity concentrations in bulk core samples varied in the range of 38-250 Bq kg(-1) in the study sites and of 22-78 Bq kg(-1) in reference site. In the sectioned cores sampled from the study areas the ranges for activity concentrations of 226Ra, total 210Pb and unsupported 210Pb are 24-77; 39-344 and 4-313 Bq kg(-1), respectively. Corresponding ranges for reference site are 37-39; 39-122 and 1-83 Bq kg(-1).  相似文献   

18.
Most of the building materials contain naturally occurring radioactive elements, the most important of which are potassium 40K and the members of two natural radioactive series, which can be represented by the isotopes of thorium 232Th and Uranium 238U. The presence of these radioisotopes in the materials causes external exposure to the people who live in the building. In addition, the disintegration of Uranium 238U increases the concentration of radon gas 222Rn and of its daughters in the house. So a systematic indoor gamma dose measurement has been performed in the dwellings of Agastheeswaram Taluk of Kanyakumari district, which is lying within the 30 km radius from the upcoming Kudankulam nuclear power plant site. The geometric mean of annual absorbed dose from gamma radiation in dwellings has been found to be 278 nGyh−1. The seasonal variation of indoor gamma dose measurements has also been studied. Significant differences have been observed in dwellings built of different materials such as concrete, tiled, etc.  相似文献   

19.
Airborne particles in fugitive emissions have been measured at a slagging fixed-bed coal-gasification pilot plant using lignite. Sampling was conducted during shutdown operations and opening of the gasifier following an aborted startup. Aerosol collected with a Sierra high-volume impactor was subjected to analysis by gas chromatography, mass spectrometry, and scanning electron microscopy; aerosol collected with an Andersen low-volume impactor was subjected to flameless atomic absorption analysis. The data show that the bulk of the trace organic material is associated with small particles: these data are similar to data on ambient air reported in the literature. Particle morphologies resemble those of fly ash from coal combustion, including smooth spheres, vesicular spheres, and crystalline material. Trace element size distributions are bimodal and resemble data for ambient air. Pb-containing particles are generally submicron, while particles containing Al, Fe, and other crustal species are mostly of supermicron size. Aluminum-based aerosol enrichment factors calculated from the lignite composition show that the composition of the aerosol resembles that of the coal, with the exception of modest enrichments of Mg, Na, As, and Pb in the submicron size range. Aerosol enrichment factors based on the earth's crustal composition are somewhat greater than those based on coal composition for several elements, suggesting potential errors in using crustal enrichment data to investigate chemical fractionation during aerosol formation.  相似文献   

20.
陆丰22-1是中国第一个正式弃置的海上油田,处于南海330m深水区.分析开发前期、中期及末期油田附近海域表层海水、表层沉积物和底栖甲壳类体内石油烃含量数据,结果表明油田附近海域环境质量较好,油田开发对环境的主要污染影响是表层海水和底栖生物体内石油类污染物质含量有所升高,尚未见生活污水和食品废弃物的排放对环境造成影响的迹...  相似文献   

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