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1.
Trends in total suspended particulates (TSP) emissioninventories were compared with ambient TSP concentrationsduring the period of 1993-1999 in the Czech Republic. TheTSP annual emission decreased within the period of observationfrom 441 300 to 67 000 of metric tonnes (by 85%). During thesame period a less pronounced downward trend from80.3 g m-3 to 31.5g m-3 (decrease by 61%)was noted also for the ambient TSP annual average. Differencebetween the two air quality indicators seems to indicate thatchanges in TSP emission inventories from year to year arebeing to some extent overestimated. Monthly ambientparticulate concentrations did not respond to overall drop inemissions proportionately but were closely associated withmonthly mean temperatures. While in the winter the correlationbetween ambient TSP and temperature was negative, in summerthe correlation between the two variables was positive. Inspring and autumn there was no clear correlation betweentemperature and ambient particulate pollution. The improvementof air quality in the Czech Republic since the economical andpolitical transformation in 1990s is substantial whendemonstrated by emission figures, however, true state ofparticulate pollution expressed by ambient levels requiresfurther attention.  相似文献   

2.
Cd, Zn, Cu, and metallothionein (MT) levels have been determined in the renal cortex and liver of 70 persons who died in Lodz and its surroundings in the years 1985–1989. The mean concentrations were: 44.9±28.6 µg Cd/g, 52.0±16.7 µg Zn/g, 2.4±1.0 µg Cu/g, 0.79±0.40 µmol Hg/g, and 3.5±1.8 µg Cd/g, 66.7±30.5 µg Zn/g, 4.9±2.1 µg Cu/g, 0.50±0.38 µmol Hg/g wet tissue in renal cortex and liver, respectively, with mean age 54.0±13.8. Smokers showed 2.4 times higher levels of Cd in the renal cortex than non-smokers. The mean body burden of Cd was 33.4±17.3 mg. Smoking increases it twofold from 22.0 mg in non-smokers to 41.8 mg in smokers.This work was supported by the grant CPBR 11.12(C-56/86) from the Institute of Rural Medicine, Lublin, Poland.Deceased.  相似文献   

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The extent of correlation in polycyclic aromatic hydrocarbon (PAH) concentration data obtained by the UK PAH Monitoring and Analysis Air Quality Network from March 2008 to November 2010 has been assessed. Application of principal component analysis (PCA) to the dataset has revealed that the concentrations of the vast majority of PAHs are very highly correlated. The use of diagnostic PAH ratios (including a new benzo[b]naph[2,1-d]thiophene/benzo[a]pyrene diagnostic ratio), and a novel 'combined diagnostic ratio - PCA' approach has revealed information about the main sources of PAH at individual Network sites, allowing the sites to be grouped in terms of those influenced by solid fuel use, industry and traffic, and those of an urban or rural nature. Solid fuel use has also been delineated from other fuel burning. Conclusions are drawn about a number of UK PAH Network sites - four sites are shown to be influenced significantly by solid fuel use, and the sites in South Wales and at London Marylebone Road are found to be located in distinct and unusual PAH pollution climates - the identification of a unique PAH pollution climate in South Wales is a key and novel conclusion of the work.  相似文献   

5.
Total gaseous mercury was collected at ten sites, which comprise part of the UK rural heavy metals monitoring network, between 2005 and 2008. Using the gold amalgam technique to capture total gaseous mercury, samples were analysed using a Tekran 2537A mercury vapour analyser. The data showed no upward or downward trend in atmospheric mercury concentrations over the period, with 4 year average concentrations between 1.3 and 1.9 ng m(-3), which are in line with other studies' observed northern hemispheric background concentrations of between 1.5 and 1.7 ng m(-3). Using data from nine of the sites, we were able to show seasonality within the data and through kriging we were able to interpolate the TGM concentrations over the UK, revealing a south-east to north-west declining concentration gradient. Using continuous speciated mercury measurements from one of the network sites, we show through wind sector analysis and air-mass back trajectories that this spatial trend is likely to be due to air masses moving over the UK from continental Europe on easterly winds. The levels of TGM recorded in the south-east of the UK also more closely match observed background TGM levels on the continent, which could indicate that the TGM concentrations from the north of the UK are a better reflection of the true North Atlantic atmospheric mercury background level.  相似文献   

6.
Large projects are often controversial projects, with wide ranging implications for host localities. Energy projects, including windfarms, nuclear power stations, and the more recent cases of fracking and nuclear waste geological disposal, provide particularly high profile cases. In response to concern there has been the emergence of a whole family of new procedures, processes and methods for their assessment and management, including the advent of Community Benefit Agreements (CBAs). This article examines some of the critical issues around the increasing use of such agreements, including: their justification, relationship to the planning process, scale of benefits (which can be very large), types of benefits, and their management and distribution. The focus is on emerging UK practice in relation to energy projects, but there will also be reference to some relevant practice elsewhere—especially in the EU and North America.  相似文献   

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Review on the annual PM10 concentrations over a 10-year period shows that Macau is subjected to severe fine particulate pollution. Investigations of its variation in monthly and daily time scales with the local meteorological records reveal further details. It is found that a distinct feature of the Asian monsoon climates, the changes of wind direction, mainly controls the general trend of PM10 concentration in a year. The monsoon driven winter north-easterly winds bring upon Macau dry and particle enriched air masses leading to a higher concentration in that period while the summer south-westerly winds transport humid and cleaner air to the region leading to a lower PM10 value. This distinct seasonal feature is further enhanced by the lower rainfall volume and frequency as well as mixing height in winter and their higher counterparts in summer. It is also found that the development of tropical cyclones near Macau could also impose episode like PM10 concentration spikes due to the pre-typhoon induced stagnant air motion followed by the swing of wind direction to the northerly.  相似文献   

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This paper examines how cumulative effects assessment (CEA) has been considered in Strategic Environmental Assessments (SEA) of regional and local plans in a number of case studies in the UK. Initially, the paper presents the legislative and regulatory requirements for assessing cumulative effects in plans and programmes in the UK. The two approaches for assessing plans in the UK, Sustainability Appraisal (SA) and SEA are discussed and in most cases, a combined SA and SEA process is undertaken by Regional and Local Planning Authorities. The strengths and weaknesses of this approach are explored, as well as their usefulness in decision making. There are problems relating to baseline, establishing trends and predicting cumulative effects at the strategic level. The issues in assessing cumulative effects within this SA/SEA framework are discussed and recommendations for improvements are made.  相似文献   

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A large series of data on dissolved antimony concentrations (900 values) from the hydrological network of Canton Geneva, Switzerland, has been statistically analysed. Data were collected from 90 sampling sites over 12 years. The watercourses surveyed (178 km) accounted for 73% of the total network. Previous studies have classified these rivers as belonging to three clearly-differentiated lithogenic zones: Alps (rivers draining crystalline regions), Jura (rivers draining carbonate-rich zones) and Plain (rivers draining molasses derived from the Alps). Antimony concentrations in the different river waters have been found to be significantly dependent on the geological characteristics of the drainage basins (median values: 0.13, 0.08 and 0.16 microg L(-1) for Alps, Jura and Plain, respectively). For antimony, it is thus possible to define background levels of the element adapted to the lithogenic characteristics for a system of interest. Since establishing background levels is an unavoidable preliminary step in any study aiming to identify and evaluate the various sources of pollution, the behaviour described here has undeniable implications for environmental surveys.  相似文献   

13.
The concentrations of organochlorine pesticides (OCPs) in fish, shrimps, cattle fat and human serum samples from the Sene-Gambian region were measured using validated analytical methodologies. The results obtained were compared with those of other existing African studies and with data from other developing countries. In fish samples, p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and HCB were detected with a frequency of 100%, whereas p,p'-dichlorodiphenyltrichloroethane (p,p'-DDT) was detected in eight, heptachlorepoxide in six and endosulfansulfate in five of the nine fish samples. Relatively low concentrations of OCPs were found in cattle and shrimp fat samples. p,p'-DDE and alpha-hexachlorocyclohexane (alpha-HCH) were the most frequently identified. The sum of HCHs ranged from undetected to 13.3 ng g-1 fat, the sum of DDTs from 11.1 to 199.2 ng g-1 fat and the sum of endosulfans from not detected to 49.7 ng g-1 fat in fish and shrimps. In serum samples, alpha-HCH, p,p'-DDE, o,p'-DDT and p,p'-DDT were detected in all 16 pooled serum samples, whereas endosulfansulfate, methoxychlor, mirex, heptachlorepoxide and endrin were detected in 15 samples with most of the concentrations below 10 ng mL-1. The concentrations of OCPs in human serum were given on a serum lipid and whole serum volume basis. The implications for the human diet of these OCP concentrations in serum were investigated by means of biomagnification factors related to the log Kow values of the targeted compounds. The current use of HCH mixtures was suggested to explain the unusually high alpha-HCH concentration. The distribution pattern of these OCPs in humans was also discussed and compared with that in other studies.  相似文献   

14.
The aim of this study has been to use a global index to measure the air quality in the city, apart from individual assessment of the values of the concentrations of the different pollutants. We calculated the ORAQI with the data obtained at four air-pollution monitoring stations located in the city of Salamanca over the period between 1993 and 2001. For the calculations, SO2, PM10, NO2, CO and O3 were used as the most significant pollutants for the surroundings of the monitoring stations. The evolution of this index over 9 years is reported, and the repercussion of the most characteristic pollutants of each season of the year on the ORAQI along the whole period analysed is studied. The importance of the summer pollution in the characterisation of the least polluted surroundings was observed. At the most polluted sites, a decrease in the values corresponding to winter occurs, leading the ORAQI to take similar values along the whole year. In general, taking into account the surroundings of all the monitoring stations, the quality of the air to which the inhabitants of the city of Salamanca are exposed to can be said to be good.  相似文献   

15.
The characteristics of Hg wet deposition were investigated in a rural area of Korea from August 2006 to July 2008. The volume weighted mean (VWM) Hg(T) concentration and cumulative Hg(T) flux were 8.8 ng L(-1) and 9.4 μg m(-2) per year, respectively. The VWM Hg(T) concentration varied seasonally, similar to the seasonal pattern in atmospheric Hg(p) concentration. The enhancement of both VWM Hg(T) and atmospheric Hg(p) concentrations in spring and winter was likely caused by the long-range transport of Hg from China. Monthly VWM Hg(T) and atmospheric Hg(p) concentrations were well correlated (R(2) = 0.36); however, there was no correlation between VWM Hg(T) and RGM (reactive gaseous mercury) concentrations, suggesting that Hg(p) was responsible for the majority of the Hg in wet deposition at this site. The VWM Hg(T) concentration in snow was statistically higher than in rain. In addition, the atmospheric Hg(p) concentration appeared to be elevated for snow events as well. This suggests that both elevated Hg(p) concentrations and the enhanced scavenging efficiency of snow for Hg(p) were responsible for the elevated VWM Hg(T) concentrations measured during snow events.  相似文献   

16.
Atmospheric deposition may be an important source of persistent organic compounds (POP) and pesticides for the Dutch coastal and inland waters. Current estimates of the atmospheric input have been made using atmospheric dispersion models. The uncertainty is however large. A project was defined with the aim to assess the input on the basis of measurements. For a period of two years (1999-2001) a monitoring network was operated. At eighteen stations, located across the whole country, air and precipitation samples were taken on a weekly and monthly basis. In these samples the concentrations of pesticides, PCB's and PAH's were determined. Up to 50 different pesticides were observed in precipitation and air. The concentration of 17 of these in precipitation exceeded the maximum permissible level for surface water and 22 exceeded the standard for drinking water of 100 ng l(-1). The input from the atmosphere to Dutch inland waters appeared to be as large as the input of pesticides by other sources such as spray drift. Model calculations were also carried out to identify the sources of these compounds. The occurrence of atrazine could be related to emissions outside the Netherlands.  相似文献   

17.
Industrial and weathering inputs of Cd and Zn to the Sepetiba Bay and basin were assessed, based on production parameters obtained from local environment and industry authorities, and literature data. The results are compared with similar evaluations from other coastal regions and field data obtained in measuring Zn and Cd transport by rivers, direct run-off and atmospheric deposition in the region. Cadmium and zinc inputs to the bay increased by three orders of magnitude relative to pre-industrial fluxes and presently reach up to 1.6 and 180 tonnes per year for Cd and Zn, respectively, which represents a large input-to-area ratio, and explains the high concentration of these metals previously reported in the estuarine biota and sediments of Sepetiba Bay. Industrial activities, mainly metallurgical and chemical, comprise 94% and 84% of the total Cd and Zn inputs to the Bay. This figure identifies the point sources as being responsible for the environmental contamination and for regional poisoning risks.  相似文献   

18.
Tehran is one of the megacities of the world with a population of over eight million. Its air is highly polluted mainly due to the suspended particulate matters, which encompasses a wide spectrum of chemical elements. These elements based on their type, size, and impact on the life cycle have various environmental and heath risks. In this research, the neutron activation method is used to determine the concentration levels of Al, Ba, Fe, Mg, and V in the urban air. Thus, two districts of Tehran with different characteristics are selected. District 21 includes much of the industries located in Tehran metropolitan and is considered as an industrial area. In contrast, district 22 lacks any significant industrial activity. It is a newly established and expanding district adjacent to district 21 with a great deal of constructional activities. For the measurement of the suspended particulate matters in the air, the various sections of the aforesaid districts with industrial, residential, heavily congested traffic, residential/commercial, residential/heavily congested traffic, and residential/industrial classifications were identified. Subsequently, 24 sampling stations were selected. The sampling of the suspended particulate matters was conducted with the aid of a high volume pump containing 125 mm cellulose filters in two different time intervals. After completion of the sampling process, the samples were prepared and sent to the research reactor of the Iran Nuclear Energy Organization for Neutron Activation. During the next steps, the radiations emitted from the samples were registered, the radiation curves were plotted, and the amounts of the trace elements were determined. As a result, the average concentration levels of Al, Ba, Fe, Mg, and V were identified to be 3.301140, 2.273658 × 10, 4.0681696 × 10???1, 3.5525475 × 10???1, and 3.04075 × 10???2 μg/m3, respectively. Moreover, the emission sources of the aforesaid elements into the air were identified. The concentration levels of these elements in the industrial and heavily congested traffic sections were higher. Finally, it was concluded that the statistical analysis of these elements presents a meaningful correlation among them.  相似文献   

19.
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   

20.
We analyzed cadmium and lead levels in feathers of mated pairs of common terns (Sterna hirundo) and in their eggs to determine if metal levels in eggs correlated with female levels, and whether there were intrapair and intermetal correlations. Eggs had significantly lower lead levels (89 ng g-1) and cadmium levels (4.0 ng g-1) than adult feathers (500 and 50 ng g-1 respectively). Adult females had higher metal levels than males. Cadmium and lead levels were correlated across families for females, males and eggs. Lead, but not cadmium, levels were correlated in females and their eggs.  相似文献   

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