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1.
Air pollution has been associated with adverse health effects. Difficulties in interpreting studies of health effects of exposure to air pollution arise in estimating exposure. Until recently, studies of effects of air pollution have relied on pollution exposure measurements obtained from fixed location air pollution stations monitoring outside air (to evaluate compliance with air quality standards, rather than to examine population exposure). However, recent evidence suggests that there are substantial differences between air pollution levels measured at such sites and levels to which people are actually exposed, i.e. personal exposure. The present study examines effects of ambient urban air pollution on persons suffering from asthma, healthy non-asthmatic subjects and school children (in 2 Canadian cities, Toronto and Hamilton). Air pollution exposure is being assessed by data obtained from: (1) conventional abatement oriented fixed location air pollution monitoring stations, (2) an extensive population oriented network, (3) inside and (4) outside structures (homes and schools) as well as (5) personal air pollution samplers. The data indicate variability in these different estimates of exposure which have implications on health effects assessment.  相似文献   

2.
考虑异质人群不同声功能需求和时空分布,对异质人群交通噪声暴露特征进行评估。通过集记人口高斯分解和噪声预测,获取特征人群分布数据和交通噪声数据;基于特征人群年龄和声功能需求,标定各年龄段人群噪声响应函数并进行归一化处理,构建异质人群噪声响应曲线;构建交通噪声暴露评估模型,结合获取数据及噪声响应曲线进行噪声暴露评估。结果表明,3类声功能区中人群噪声暴露与年龄变量均呈现类抛物线趋势,40岁左右人群暴露影响较儿童和老人低59.9%左右。人均噪声暴露在夜间明显偏高,尤其在声功能需求较高的第1类声功能区,其人均噪声超标值比昼间高7 d B。特征人群的空间分布对噪声暴露影响显著,工作时段学校区域适学人群集中,其总噪声暴露风险为同等状况住宅区的1.2倍。综合考虑人群特征和时空分布等因素,可更科学地进行区域交通噪声污染评估。  相似文献   

3.
To study whether the urinary 1-hydroxypyrene (1-OHP) could be the biomarker of atmospheric PAHs, a small-scale pilot study was carried out on the relation of 1-OHP vs PAHs with the traffic policemen in Beijing of smokers and nonsmokers to be subgroups in both the exposure and control groups. Both the PAHs and 1-OHP were analyzed with high performance liquid chromatography (HPLC). The ambient concentrations of PAHs were different at the different sites (the average sum of PAHs (TPAH) were 12.36, 16.27, 18.37 ng/m3 at the suburban residential, police station and high traffic area, respectively.), but considerably lower than the personal-exposure concentrations (the average TPAH were 65.84 and 47.28 ng/m3 for patrol cars and inspection station, respectively). Pyrene was correlated well with BaP and the summed PAHs (TPAH), with the correlation coefficients (R) of 0.79, 0.87 for ambient level and 0.92, 0.96 for personal exposure, respectively. The average of 1-hydroxypyrene of smokers and nonsmokers were 0.39, 0.15 μmol/mol creatinine in control group and 0.57, 0.33 μmol/mol creatinine in exposure group, respectively. The better correlation of pyrene to BaP and TPAH especially for personal exposure samples indicated that the probability of urinary 1-hydroxypyrene, the metabolite of pyrene, to be the biomarker of total PAH. Nonsmokers in the exposure and control groups had indistinguishable levels of 1-OHP, presumably because the ambient levels of pyrene were so similar (the average were 3.25, 3.20 ng/m3 at the police station and high traffic area, respectively.). Smokers in the control group had significantly higher 1-OHP than that of the nonsmokers, but showed indistinguishable differences in the exposure group. These results suggested that urinary 1-OHP could be a biomarker of PAHs only when the level of PAHs was at a relatively higher level. Smoking as an important influencing factor need to be controlled carefully.  相似文献   

4.
The purpose of this study was to develop a method for assessing generalised N leaching estimates from large areas of agricultural land. The system developed was based on calculating a number of N leaching estimates for different typical cropping situations. The estimates were normalised with respect to varying weather conditions and crop production. The different cropping situations were described by setting up a matrix consisting of crucial factors influencing leaching such as soils, crops and climate. Nitrogen leaching was then estimated for a number of combinations of these factors. Calculations were made for three different regions where all the major crops were cultivated on soils with seven different textures and four different organic-N classes and two fertilisation regimes. The three regions are representative of climates and agricultural practices in some of the major agricultural areas in Sweden. The model used was the SOILN model. Leaching of nitrogen from the root zone showed large variations. The range was from 1 to 50 kg ha−1 for different soils and crops when only fertiliser N was applied. Leaching varied both due to different climates and differences in cultivation practices between the regions. Leaching decreased in a south-north gradient. Leaching increased as a result of greater mineralisation when the organic matter content in the soils was increased, leaching was less from soils with a high clay content and was very small for the heavy clay soil. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

5.
Air pollution in the workplace environment due to industrial operation have been found to cause serious occupational health hazard. Similarly, heat stress is still most neglected occupational hazard in the tropical and subtropical countries like India. The hot climate augments the heat exposure close to sources like furnaces. In this study an attempt is made to assess air pollution and heat exposure levels to workers in the workplace environment in glass manufacturing unit located in the State of Gujarat, India. Samples for workplace air quality were collected for SPM, SO2, NO2 and CO2 at eight locations. Results of workplace air quality showed 8-hourly average concentrations of SPM: 165–9118 μg/m3, SO2: 6–9 μg/m3 and NO2: 5–42 μg/m3, which were below the threshold limit values of workplace environment. The level of CO2 in workplace air of the plant was found to be in the range 827–2886 μg/m3, which was below TLV but much higher than the normal concentration for CO2 in the air (585 mg/m3). Indoor heat exposure was studied near the furnace and at various locations in an industrial complex for glass manufacturing. The heat exposure parameters including the air temperature, the wet bulb temperature, and the globe parameters were measured. The Wet Bulb Globe Temperature (WBGT), an indicator of heat, exceeded ACGIH TLVs limits most of the time at all the locations in workplace areas. The recommended duration of work and rest have also been estimated.  相似文献   

6.
为掌握东营市化工聚集区地下水受有机污染的总体程度,对该市三县两区96个调查点位的地下水TOC进行了监测。结果表明:化工聚集区地下水TOC质量浓度分布范围为1.5~19.6 mg/L,87.5%的数据集中在2~10 mg/L区段,其中2~4 mg/L的区段数据最密集,数据分布呈对数正态分布。受区域内外部因素共同影响,地下水超标率和异常值比率分别达到62.5%和18.8%,且由南向北呈明显上升趋势;存在浓度均值超标和异常突变数据的化工聚集区数量分别占调查总量的75%和62.5%。地下水TOC受环境地质分布影响显著,黄泛平原区比山前平原区污染范围和程度更高;河口区和广饶井罐区分别是东营市和广饶县地下水污染最严重的地区,广饶县西北部是东营市地下水TOC水质最好的地区。  相似文献   

7.
通过对连云港市农业非点源氮磷污染对水环境影响的研究,掌握了连云港市农业非点源氮磷污染情况及氮磷在土壤中的转化机制,监测分析了水环境氮磷污染现状及氮磷对水环境的影响途径,提出了控制农业非点源氮磷对水体环境污染的措施。  相似文献   

8.
9.
新污染物环境监测涉及新污染物识别、环境风险评估与管控成效评估等多个目标,科学的环境调查监测有助于最大程度支撑新污染物治理。分析了环境暴露评估对新污染物监测介质、监测尺度、监测数据质量及代表性等方面的要求,借鉴发达国家对新污染物的环境监测实践经验,提出了我国新污染物环境监测总体要求,主要包括:从筛查监测、评估监测和监督性监测3个层次开展监测,以发现问题、评估风险、监督成效。评估监测应包含污水处理厂活性污泥,排放源周边地表水、沉积物、大气、土壤、环境生物等介质,应符合局部尺度环境暴露评估对监测数据的要求,监测报告应包含足够的信息。  相似文献   

10.
11.
南通地区地下水中砷的形态分布特征研究   总被引:1,自引:0,他引:1  
2012年开展南通市1∶50000水文地质调查,对监测网内地下水进行采样分析,建立了基于液相色谱-电感耦合等离子体质谱联用测定地下水中砷形态的方法,该方法检出限为0.1μg/L。样品分析表明,南通地区地下水中砷的形态以三价无机砷为主,有机砷以砷胆碱(AsB)和乙基砷(DMA)为主,样品中未检出五价无机砷。通过砷形态研究表明,南通近海地区地下水中砷的质量浓度较低(<0.5μg/L),主要以 As(Ⅲ)为主,不存在其他砷的形态;近长江地区地下水中砷的质量浓度较高(>1.0μg/L),砷形态以 As(Ⅲ)和 DMA为主。  相似文献   

12.
A correct characterization of the status and trend of forest condition is essential to support reporting processes at national and international level. An international forest condition monitoring has been implemented in Europe since 1987 under the auspices of the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests). The monitoring is based on harmonized methodologies, with individual countries being responsible for its implementation. Due to inconsistencies and problems in sampling design, however, the ICP Forests network is not able to produce reliable quantitative estimates of forest condition at European and sometimes at country level. This paper proposes (1) a set of requirements for status and change assessment and (2) a harmonized sampling strategy able to provide unbiased and consistent estimators of forest condition parameters and of their changes at both country and European level. Under the assumption that a common definition of forest holds among European countries, monitoring objectives, parameters of concern and accuracy indexes are stated. On the basis of fixed-area plot sampling performed independently in each country, an unbiased and consistent estimator of forest defoliation indexes is obtained at both country and European level, together with conservative estimators of their sampling variance and power in the detection of changes. The strategy adopts a probabilistic sampling scheme based on fixed-area plots selected by means of systematic or stratified schemes. Operative guidelines for its application are provided.  相似文献   

13.
典型城市工业区TSP中重金属污染研究   总被引:1,自引:2,他引:1  
以徐州市北郊工业区作为研究对象,探讨工业型城市大气总悬浮颗粒物中重金属元素的时空分布特征。监测结果表明,该区大气TSP中重金属污染较为严重,单个样品中重金属铅、锌、镉、铬、铜和锰的最高含量分别达350.9、1037.9、5.5、16.3、17.8、238.5mg/kg;元素浓度呈秋冬季偏高,夏秋季偏低的趋势;空间分布充分体现了与污染源地域分布的一致性。  相似文献   

14.
以国家重点生态功能区县域环境监测质量评价为目标,综合应用德尔菲法、层次分析法和模糊综合评价法,构建了国家重点生态功能区县域环境监测质量评价方法,并确定了评价因子、权重系数、计算方法。该方法评价指标共分为三层:第一层为目标层,即国家重点生态功能区县域环境监测质量;第二层为准则层,包括人员及资质、现场监测、实验室管理、报告编制及数据上报;第三层为方案层,包括人员操作、持证上岗、资质认定、人员培训、水质布点采样流转情况、空气自动站运维情况、现场质控实施情况、实验室环境条件、样品试剂的保存与管理、仪器检定与校准、实验室质量控制实施情况、数据填报软件运行情况、监测报告规范性等13个评价要素。经矩阵一致性检验确定了各评价要素的权重,将该权重与各要素得分运算后得到县域环境监测质量评价结果。在此基础上,选取广东、山西、陕西、四川和青海等5个省份的15个国家重点生态功能区县域作为典型区开展了实地调研,并应用评价体系对其进行了监测质量等级评价。结果表明,15个典型县域中,环境监测质量等级为优的县域占13.3%,一般、较差的县域分别占66.7%、20%。县域环境监测承担单位在资质、报告编制及数据上报方面表现较好,在现场监测、人员操作方面问题突出,在实验室管理方面有待提升。  相似文献   

15.
As part of the European Community Respiratory Health Survey (ECRHS) PM2.5 (particles collected with an upper 50% cut point of 2.5 μm aerodynamic diameter) was measured using an EPA-WINS (Environmetal Protection Agency Well Impactor Ninety-six) sampler. The monitoring schedule was restricted to 7 days per month for one year. Simultaneously, during this one year study period a collocated Harvard Impactor (HI) was run on a daily basis in Erfurt, Germany. Here we validated the reliability of annual, seasonal and monthly means estimated using the ECRHS scheme (measurements taken less than 25% of the whole study period) with the ‘true’ long-term averages, which were estimated using all available daily means.The daily PM2.5 means, obtained by both instruments operated in parallel, were only slightly different (the mean difference between EPA-WINS and HI was 1.8 μg m−3 and 2.8 μg m−3 for the winter means). The values obtained by the two instruments were highly correlated (r = 0.95).In view of that negligible difference, no additional bias was seen with respect to the annual and the winter means estimated by the two different sampling strategies (the difference was 1.7 μg m−3 and 2.7 μg m−3, respectively). Monthly means, however, can only be considered to be a crude estimate that may substantially under- or overestimate the true monthly mean value.  相似文献   

16.
石油化工园区周边土壤中多环芳烃的分布研究   总被引:2,自引:1,他引:2  
采集锦州市石油六厂工业区、交通运输区及农业区土壤,采用高效液相色谱/质谱联用仪分析测定土样中16种PAHs的总含量(∑PAHs):工业区均值为386.19μg/kg、交通运输区均值为328.54μg/kg、农业区均值为192.64μg/kg;致癌性PAHs的总含量(∑PAHscare):工业区均值为147.97μg/kg、交通运输区均值为131.52μg/kg、农业区均值为73.83μg/kg;不同功能区PAHs成分组成规律基本一致,PAHs以3环和4环为主,土壤中PAHs成分比例规律为4环>3环>2环>5环>6环;无论是土壤中∑PAHs还是∑PAHscare含量规律,都为工业区>交通运输区>农业区。工业区石油类污染较为严重,交通运输区及农业区土壤中PAHs污染主要来源于化石燃料的燃烧及农业用品的施用。  相似文献   

17.
上海市工业区大气污染预警监测信息平台研究与设计   总被引:1,自引:0,他引:1  
根据上海市工业区大气污染排放特征,在构建大气特征污染监控网络的基础上,搭建了工业区大气污染预警监测信息平台,并研究了适用于大气特征污染自动站的通信传输规范,确保数据联网和应用。平台设置了大气质量监控、大气数据管理、污染源一厂一档、大气质量分析评价、污染源溯源分析、应急监测数据管理、智能移动终端查询等7个子系统,可为上海市工业区大气污染预警和管控提供实时监测数据。  相似文献   

18.
在暴露情景假设和评估模型的确定下,有必要对污染场地的风险计算结果有影响的模型参数开展敏感性分析,以便在开展土壤健康风险评估工作时,提高评估的准确性和科学性,节约修复成本。以上海市某污染场地为例,对模型参数敏感性开展敏感性分析。贡献率结果显示,经口摄入土壤和皮肤接触土壤为场地表层污染土壤的主要致癌风险暴露途径。敏感性分析结果显示,致癌风险与体重呈反向变化,当体重参数减小时,暴露风险将向不利的方向移动。当体重参数在大范围减小时,敏感程度较高。致癌风险与暴露周期、暴露频率、每日摄入土壤量、暴露皮肤表面积、皮肤表面土壤粘附系数呈同向变化,当这些参数增大时,暴露风险将向不利的方向移动;其中暴露周期和暴露频率的敏感程度中等。上海市敏感用地下苯并(a)蒽、苯并(b)荧蒽、茚并(1,2,3-c,d)芘、苯并(a)芘、二苯并(a,h)蒽风险控制值分别为0.726、0.726、0.726、0.072 6、0.072 6 mg/kg。  相似文献   

19.
为控制湖西区入湖营养盐量,需要对太湖湖西区河网进行N、P营养盐监测与输移路径模拟.结果显示,宜溧地区营养盐输移规律基本表现为径流输移;常州、金坛地区京杭运河以南河网区虽然日输移路径较为复杂,但是洪期、年输移路径却一致;而京杭运河以北河网营养盐输移规律最为复杂,不仅表现为日输移路径的规律性差,而且洪期、年净输移路径相反....  相似文献   

20.
Defining “forest land” is a complex issue and has been discussed for decades. Today, a confusing multitude of definitions of forest land are in use making comparison of forest area figures difficult. But currently, comparability is receiving much attention when it comes to install market mechanisms for ecosystem services. Minimum crown cover is among the most frequently employed criteria of forest definitions. However, the size of the reference area on which the crown cover percent is to be measured is usually not defined. But how does a change of the size of the reference area affect the derived forest cover? In this study, we analyze the interactions of the crown cover threshold and the size of the reference area. We start with analyzing the interactions using a simple geometric model of the forest edge. Then, we extend the analysis by simulating artificial landscapes where we study how the interaction is affected by different degrees of forest fragmentation, crown cover proportion, and spatial resolution of the data source used. The simulation showed that large differences in forest cover (>50 %) may result for a fixed crown cover threshold value, just by changing the size of the reference area, where the magnitude of this effect is a function of the chosen threshold value and the spatial configuration of the crowns. As a consequence of the findings, we see an urgent need to complete forest definitions by defining a reference area in order to reduce uncertainties of forest cover estimates.  相似文献   

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