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1.
Six Norway spruce stands (Picea abies L.) in southern Sweden and six in the northeastern Czech Republic, 12 stands in total, were selected for short-term investigations during the summer and autumn of 1991. In each of the plots, an assessment of foliar damage and dendrometric measurement of the trees was made. Soil and leaf samples were collected and analyzed for their chemical composition. After statistical evaluation of the most important correlations, it was concluded that the main cause of tree damage in both countries was through the acidification of the soils. In both countries, but especially in the Czech Republic, heavy metal accumulation in the humus layer was observed. The main results of the study were the discovery of the similarity of damage processes in the two countries, despite the differences in their geographic location and ambient air pollution levels  相似文献   

2.
This paper presents the application of the Integrated Transport Effect Modelling System (ITEMS) in the city of Kaunas, Lithuania, taking into consideration some factors such as existing vehicle fleet, traffic flows, and ambient air quality monitoring data. The objective of this study is to estimate the exhausts of CO, NOx, and SO2 released by motor vehicles in relation to predictive traffic policy measures in Kaunas. The study analyses the extent to which some traffic policies and future trends may influence the ambient air pollution in urban environment. The comparative analysis of the influence of different traffic policies is presented.  相似文献   

3.
We use air mass back trajectory analysis of persistent organic pollutant (POP) levels monitored at a regional background site, Ko?etice, Czech Republic, as a tool to study the effectiveness of emission reduction measures taken in the last decade in the region. The representativity of the chosen trajectory starting height for air sampling near ground was ensured by excluding trajectories starting at time of inversions lower than their starting height. As the relevant pollutant sources are exclusively located in the atmospheric boundary layer, trajectory segments above this layer were also excluded from the analysis. We used a linear time weight to account for the influence of dispersion and deposition on trace components abundances and to quantify the ground source loading, a continuous measure for the influence of surface emissions. Hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), DDT, and two time periods, the years 1997–1999 and 2004–2006, were studied. The pollutant levels transported to Ko?etice decreased for all substances except HCB. Except for lindane seasonal emissions were insignificant. Increasing emissions of HCB were at least partly linked to the 2002 floods in the Danube basin. Major emissions of 1997–1999 which decreased significantly were in France (lindane), western Poland, Hungary and northern ex-Yugoslavia (technical HCH), and the Czech Republic (DDT). Emissions remaining in 2004–2006 include HCB and DDT in the northern Czech Republic, HCB and PCBs in Germany. Besides changes in emission strength meteorological factors influence the level of transported pollutant concentrations. The prevailing air flow pattern limits the geographic coverage of this analysis to central Europe and parts of western Europe. However, no POP monitoring stations exist in areas suitable for a possible extension of the study area.  相似文献   

4.
A comparison of the modelling results of persistent, bioaccumulative and toxic (PBT) chemicals is presented with measurements. Contribution will present mean annual concentrations calculated and observed at EMEP stations and their ratios. The comparison of the calculated results with older results indicates that the model modification improved the agreement with measurement data. PBT compounds in ambient air are monitored in the area of Kosetice observatory (professional observatory of the Czech Hydrometeorological Institute located in south Bohemia). Calculated and measured mean annual concentrations of PBTs in precipitation, soil, vegetation and their ratios are presented. It should be mentioned that the number of measurements in such compartments as seawater, soil and vegetation is insufficient for model verification at present. The agreement between results from MSC-East models and results from long-term regional air background monitoring in Central Europe is good.  相似文献   

5.
Air quality zones are used by regulatory authorities to implement ambient air standards in order to protect human health. Air quality measurements at discrete air monitoring stations are critical tools to determine whether an air quality zone complies with local air quality standards or is noncompliant. This study presents a novel approach for evaluation of air quality zone classification methods by breaking the concentration distribution of a pollutant measured at an air monitoring station into compliance and exceedance probability density functions (PDFs) and then using Monte Carlo analysis with the Central Limit Theorem to estimate long-term exposure. The purpose of this paper is to compare the risk associated with selecting one ambient air classification approach over another by testing the possible exposure an individual living within a zone may face. The chronic daily intake (CDI) is utilized to compare different pollutant exposures over the classification duration of 3 years between two classification methods. Historical data collected from air monitoring stations in Kuwait are used to build representative models of 1-hr NO2 and 8-hr O3 within a zone that meets the compliance requirements of each method. The first method, the “3 Strike” method, is a conservative approach based on a winner-take-all approach common with most compliance classification methods, while the second, the 99% Rule method, allows for more robust analyses and incorporates long-term trends. A Monte Carlo analysis is used to model the CDI for each pollutant and each method with the zone at a single station and with multiple stations. The model assumes that the zone is already in compliance with air quality standards over the 3 years under the different classification methodologies. The model shows that while the CDI of the two methods differs by 2.7% over the exposure period for the single station case, the large number of samples taken over the duration period impacts the sensitivity of the statistical tests, causing the null hypothesis to fail. Local air quality managers can use either methodology to classify the compliance of an air zone, but must accept that the 99% Rule method may cause exposures that are statistically more significant than the 3 Strike method.

Implications: A novel method using the Central Limit Theorem and Monte Carlo analysis is used to directly compare different air standard compliance classification methods by estimating the chronic daily intake of pollutants. This method allows air quality managers to rapidly see how individual classification methods may impact individual population groups, as well as to evaluate different pollutants based on dosage and exposure when complete health impacts are not known.  相似文献   


6.
Eye irritation measurements are available from smog chamber solar Irradiations of selected hydrocarbon-nitrogen oxide mixtures. These results have been used to compute eye irritation intensity parameters for formaldehyde, acrolein, peroxyacetyl nitrate, and peroxypropionyl nitrate. Peroxypropionyl nitrate is the most irritating of these four substances. The relative contribution of various pairs of eye Irritants in ambient air mixtures to eye irritation has been calculated from the ambient air concentrations and the eye irritation intensity parameters. The relative contribution of the four eye irritants to a "typical" ambient air mixture has been computed. Formaldehyde appears to be the single most significant eye irritant. Other potential ambient air eye irritants are discussed. The relationships between the hydrocarbon control strategies and eye irritation are considered.  相似文献   

7.

Background, aim and scope

The breast milk has been recommended to carry out as a monitoring tool for effectiveness evaluation of the Stockholm Convention on Persistent Organic Pollutants (POPs). Polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloro-ethane (DDT) and its metabolites (DDX), hexachlorbenzene (HCB) and isomers of hexachlocyklohexane (HCHs) have been monitored in the breast milk of nursing mothers in the Czech Republic since 1994 as a part of The Environmental Health Monitoring System. Knowledge about long-term POPs distribution and accumulation in the human body is crucial to understanding uptake, degradation and subsequent effects as well as to conduct risk assessments. The main aim of this study is to evaluate 15-years long-term trends of selected POPs in human milk in the Czech Republic and to elucidate the questionnaire information about the age, parity and social habits, to the final concentrations. This effectiveness evaluation of POPs restriction is quite precisely after 15-years monitoring campaigns.

Materials, methods and results

The human milk samples (4,753 samples) were analysed for a number of chlorinated organic chemicals including PCBs and selected chlorinated pesticides (OCPs, HCB, HCHs, DDX). The relative change of concentration per year for all chemicals was analysed. The remaining percentages of POPs in breast milk in comparison to 1994 are also expressed. Czech population half-lives of POPs in breast milk, derived from either linear or exponential models were computed.

Conclusions and perspectives

The long-term data indicates a continuation of a decreasing trend of POPs concentrations on breast milk. Our study did not confirm lactation and parity as an important outflux resulting in the decrease in concentrations in mothers, which is in the antagonism with most of the studies. The higher BMI was associated with higher amounts of HCB and lower amounts of higher chlorinated PCBs. The results confirm the effectiveness of restrictions of POPs usage in the Czech Republic. This ongoing long-term study is very useful tool for parametric effectiveness evaluation of Stockholm Convention.  相似文献   

8.
裸土风蚀型开放源起尘机制研究进展   总被引:3,自引:0,他引:3  
中国北方多个城市空气颗粒物来源解析结果表明,开放源是空气颗粒物污染的主要来源,裸土风蚀型开放源是主要的排放源类.对裸土风蚀型开放源起尘机制进行了诠释,提出了裸土风蚀型开放源、裸土风蚀起尘、裸土风蚀尘的概念,并对裸土风蚀型开放源的风蚀影响因素进行了研究,为城市空气质量达标及空气颗粒物污染防治提供科学参考.  相似文献   

9.
The capability of passive air sampling to be employed in the evaluation of direct genotoxicity of ambient air samples was assessed. Genotoxic effects of the total extracts from the polyurethane foam filters exposed for 28 days during a regional passive air sampling campaign were investigated. Twenty sampling sites were selected in Brno city on the area of approximately 20x20 km in October and November 2004. Brno is the second largest city of the Czech Republic, highly industrialized with approximately 370,000 of permanent inhabitants. The levels of PAHs, PCBs, and chlorinated pesticides were determined in all samples. Fraction of each extract was also assayed in the bacterial genotoxicity test using Escherichia coli sulA::lacZ. Complete dose-response relationships of the air extracts were determined. The statistical analysis showed significant correlation between observed biological effects and PAHs concentrations in samples.  相似文献   

10.
Good quality data apt for an assessment of temporal trends of polychlorinated dibenzo-p-dioxins and furans (PCDDs/Fs) in soils are difficult to obtain since there is a general lack of information on their residues in soils. Variability of soil profiles, non-homogeneity of samples, and often also inconsistency of applied sampling procedures further complicate this problem. To assess spatial and temporal trends of contamination, three soil sampling campaigns have been performed over the period of 12 years at the mountain forest sites in the Czech Republic. Relation between the air, needle and soil contaminations was addressed in addition to time-related variability of soil. It has been confirmed that soil is a good matrix for evaluation of spatial distribution of persistent organic pollutants (POPs) but difficult for establishment of temporal trends. A slow rate of the soil-forming processes and their site-specificity was generally the major source of uncertainties.  相似文献   

11.
Environmental Science and Pollution Research - The Moravian-Silesian region of the Czech Republic with its capital city Ostrava is a European air pollution hot spot for airborne particulate matter...  相似文献   

12.
We investigated lichen diversity in temperate oak forests using standardized protocols. Forty-eight sites were sampled in the Czech Republic, Slovakia and Hungary. The effects of natural environmental predictors and human influences on lichen diversity (lichen diversity value, species richness) were analysed by means of correlation tests. We found that lichen diversity responded differently to environmental predictors between two regions with different human impact. In the industrial region, air pollution was the strongest factor. In the agricultural to highly forested regions, lichen diversity was strongly influenced by forest age and forest fragmentation. We found that several natural factors can in some cases obscure the effect of human influences. Thus, factors of naturality gradient must be considered (both statistically and interpretively) when studying human impact on lichen diversity.  相似文献   

13.
Abstract

The use of sorbents has been proposed to remove volatile organic compounds (VOCs) present in ambient air at concentrations in the parts-per-billion (ppb) range, which is typical of indoor air quality applications. Sorbent materials, such as granular activated carbon and molecular sieves, are used to remove VOCs from gas streams in industrial applications, where VOC concentrations are typically in the parts-per-million range. A method for evaluating the VOC removal performance of sorbent materials using toluene concentrations in the ppb range is described. Breakthrough times for toluene at concentrations from 2 to 7500 ppb are presented for a hydrophobic molecular sieve at 25% relative humidity. By increasing the ratio of challenge gas flow rate to the mass of the sorbent bed and decreasing both the mass of sorbent in the bed and the sorbent particle size, this method reduces the required experimental times by a factor of up to several hundred compared with the proposed American Society of Heating, Refrigerating, and Air-Conditioning Engineers method, ASHRAE 145P, making sorbent performance evaluation for ppb-range VOC removal more convenient. The method can be applied to screen sorbent materials for application in the removal of VOCs from indoor air.  相似文献   

14.
Background, Aim and Scope A series of severe air pollution episodes in Europe and North America prior to 1960 have focused scientific and regulatory attention on the adverse effects of air pollution on human health. As a consequence of significant reductions in ambient air pollution levels in the intervening years, scientists and public health officials have become more concerned with the potential health effects of exposure to routine concentrations of air pollution. Several recent time series studies conducted world-wide have found relatively low levels of air pollutants that are below national standards were associated with adverse effects on mortality and morbidity. This study examined the effects of ambient air pollution indicators on the daily rate of pediatric hospital admissions for asthma in the Oklahoma City Metropolitan area from 2001-2003. Results: Negative binomial regression analysis revealed significant relationships between the total number of hospitalizations per day and the one-hour maximum NO2 level, the proportion of susceptible children < 5 years old, and the ratio of temperature to humidity. Discussion: This study of the total number of children aged ≤ 14 years old experiencing hospitalizations on a daily basis in the Oklahoma City area from 2001-2003 underscores factors other than ambient air pollution, especially when concentrations are low, affect hospitalizations for pediatric asthma. For example, information related to indoor air quality, health care, family history, and exposure to environmental tobacco smoke and other irritants are not obtainable. Yet, those factors are risk drivers for asthma. Similarly, health privacy requirements prevented obtaining data on physiological factors specific to each child such as differentials in airways functional capacity or other impairments influenced asthma exacerbation. This makes calculating relative risk inappropriate. Conclusions: Although ambient air pollution concentrations and meteorological conditions influence pediatric asthma hospitalizations, they are not the major predictors in the Oklahoma City metropolitan area. This is consistent with other research that finds limited effects associated with low levels for concentrations of the criteria pollutants.  相似文献   

15.
The use of sorbents has been proposed to remove volatile organic compounds (VOCs) present in ambient air at concentrations in the parts-per-billion (ppb) range, which is typical of indoor air quality applications. Sorbent materials, such as granular activated carbon and molecular sieves, are used to remove VOCs from gas streams in industrial applications, where VOC concentrations are typically in the parts-per-million range. A method for evaluating the VOC removal performance of sorbent materials using toluene concentrations in the ppb range is described. Breakthrough times for toluene at concentrations from 2 to 7500 ppb are presented for a hydrophobic molecular sieve at 25%) relative humidity. By increasing the ratio of challenge gas flow rate to the mass of the sorbent bed and decreasing both the mass of sorbent in the bed and the sorbent particle size, this method reduces the required experimental times by a factor of up to several hundred compared with the proposed American Society of Heating, Refrigerating, and Air-Conditioning Engineers method, ASHRAE 145P, making sorbent performance evaluation for ppb-range VOC removal more convenient. The method can be applied to screen sorbent materials for application in the removal of VOCs from indoor air.  相似文献   

16.
The Federal Clean Air Act (FCAA) framework envisions a federal-state partnership whereby the development of regulations may be at the federal level or state level with federal oversight. The U.S. Environmental Protection Agency (EPA) establishes National Ambient Air Quality Standards to describe “safe” ambient levels of criteria pollutants. For air toxics, the EPA establishes control technology standards for the 187 listed hazardous air pollutants (HAPs) but does not establish ambient standards for HAPs or other air toxics. Thus, states must ensure that ambient concentrations are not at harmful levels. The Texas Clean Air Act authorizes the Texas Commission on Environmental Quality (TCEQ), the Texas state environmental agency, to control air pollution and protect public health and welfare. The TCEQ employs three interactive programs to ensure that concentrations of air toxics do not exceed levels of potential health concern (LOCs): air permitting, ambient air monitoring, and the Air Pollutant Watch List (APWL). Comprehensive air permit reviews involve the application of best available control technology for new and modified equipment and ensure that permits protect public health and welfare. Protectiveness may be demonstrated by a number of means, including a demonstration that the predicted ground-level concentrations for the permitted emissions, evaluated on a case-by-case and chemical-by-chemical basis, do not cause or contribute to a LOC. The TCEQ's ambient air monitoring program is extensive and provides data to help assess the potential for adverse effects from all operational equipment in an area. If air toxics are persistently monitored at a LOC, an APWL area is established. The purpose of the APWL is to reduce ambient air toxic concentrations below LOCs by focusing TCEQ resources and heightening awareness. This paper will discuss examples of decreases in air toxic levels in Houston and Corpus Christi, Texas, resulting from the interactive nature of these programs.

Implications: Texas recognized through the collection of ambient monitoring data that additional measures beyond federal regulations must be taken to ensure that public health is protected. Texas integrates comprehensive air permitting, extensive ambient air monitoring, and the Air Pollutant Watch List (APWL) to protect the public from hazardous air toxics. Texas issues air permits that are protective of public health and also assesses ambient air to verify that concentrations remain below levels of concern in heavily industrialized areas. Texas developed the APWL to improve air quality in those areas where monitoring indicates a potential concern. This paper illustrates how Texas engaged its three interactive programs to successfully address elevated air toxic levels in Houston and Corpus Christi.  相似文献   

17.
Total mercury concentrations (as a sum of vapor and particulate mercury) were measured in 24-h samples of ambient air in 20 different localities of the Slovak Republic eight times during the period 1996-1997. Vapor mercury was analyzed on site by atomic fluorescence with amalgamation technique. Particulate mercury was determined by vapor hydride atomic absorption spectrometry after wet digestion of filters with particulate air samples. The results showed that 34% of the 160 individual total mercury concentrations exceeded 5 ng/m3--the ambient air quality guideline value recommended by the WHO. The range of total mercury concentrations in the ambient air of Slovakia was: 1.13-3.98 ng/m3 (geom. mean 2.63) in the background area; 2.25-5.27 ng/m3 (geom. mean 3.64) in the agricultural areas; 1.73-20.53 ng/m3 (geom. mean 4.57) in the urban areas; and 1.53-39.85 ng/m3 (geom. mean 5.28) in the industrial areas. The highest mercury levels occurred in areas with metallurgical industry and coal combustion. The predominant form of mercury present in air was vapor mercury. The particulate fraction of mercury in ambient air (as a percentage of total mercury) varied widely from 0.4% to 42.1% (geom. mean = 4.4%). This fraction was lower in agricultural areas (2.3%) than in urban areas (5.3%). Although the atmospheric vapor mercury concentrations were slightly higher in summer than in winter, a direct correlation of vapor mercury concentrations and ambient air temperature was not found. Furthermore, the particulate mercury concentrations did not correlate with total particulate levels.  相似文献   

18.
Abstract

The ambient air quality standards (AAQS) of twenty-one nations for eight commonly regulated substances are presented. Many countries are adding a receptor-based component to their air quality management, which traditionally have been emission oriented. Automation of air quality monitoring stations has meant that local air quality evaluation can now be more easily achieved. However, a majority of countries have no active air quality standards (emission or receptor-based) or ambient air quality monitoring. One possible monitoring procedure is outlined and the variation in international standards is discussed.  相似文献   

19.
Weather condition is one of the most important factors affecting spatial and temporal distributions of air pollutants, especially for short-term air dispersion. Abnormal weather conditions might lead to higher or lower ambient air concentrations than they would be under normal weather conditions. Therefore, testing for normality of weather conditions during the air monitoring period is an essential step for evaluating ambient air monitoring results. In this paper, a distance method was used to select a most representative weather station from the available candidates. An array of meteorological elements were identified that affect air dispersion and transportation. A statistical method was used to determine whether the weather conditions during the air monitoring period were significantly different from that of previous years. Using methyl bromide ambient air monitoring as a case study, this paper documents the methods, procedures, and results of weather analysis for Monterey, Santa Cruz, and Kern Counties during ambient air monitoring periods for methyl bromide in the year 2000. With a few exceptions, the meteorological elements and atmospheric stability factors, such as wind speeds, wind directions, and stability classes, during the monitoring period were in the normal range. Although there were higher frequencies of stable atmospheric conditions in Monterey/Santa Cruz Counties than in Kern County, weather conditions during the monitoring period were not significantly different from normal local weather conditions of previous years. Consequently, the subchronic air concentrations observed during the ambient air monitoring periods for methyl bromide in the year 2000 was taken under typical weather conditions of those areas at that time of the year.  相似文献   

20.
杭州市空气颗粒物污染特征及变化规律研究   总被引:3,自引:0,他引:3  
根据2006—2010年杭州市空气颗粒物的监测数据及2002、2006、2008年空气颗粒物来源解析结果,对杭州市空气颗粒物浓度、化学组分与污染来源等特征的变化规律进行分析,以期为空气颗粒物污染控制提供决策依据。结果表明,近年来杭州市PM10浓度有所下降,但一类功能区PM10仍超出《环境空气质量标准》(GB 3095—1996)的要求(≤0.04mg/m3),杭州市空气颗粒物污染以细颗粒物为主,空气颗粒物的二次转化、机动车尾气尘等产生的二次粒子污染相对严重;煤烟尘对杭州市PM10的贡献率下降明显,城市扬尘、二次粒子和机动车尾气尘对PM10的贡献率有所增加,是杭州市PM10的主要来源。  相似文献   

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