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1.
Control of workplace exposure to beryllium is a growing issue in the United States and other nations. As the health risks associated with low-level exposure to beryllium are better understood, the need increases for improved analytical techniques both in the laboratory and in the field. These techniques also require a greater degree of standardization to permit reliable comparison of data obtained from different locations and at different times. Analysis of low-level beryllium samples, in the form of air filters or surface wipes, is frequently required for workplace monitoring or to provide data to support decision-making on implementation of exposure controls. In the United States and the United Kingdom, the current permissible exposure level is 2 microg m(-3) (air) and the United States Department of Energy has implemented an action level of 0.2 microg m(-3) (air) and 0.2 microg/100 cm(2) (surface). These low-level samples present a number of analytical challenges, including (1) a lack of suitable standard reference materials, (2) unknown robustness of sample preparation techniques, (3) interferences during analysis, (4) sensitivity (sufficiently low detection limits), (5) specificity (beryllium speciation) and (6) data comparability among laboratories. Additionally, there is a need for portable, real-time (or near real-time) equipment for beryllium air monitoring and surface wipe analysis that is both laboratory-validated and field-validated in a manner that would be accepted by national and/or international standards organizations. This paper provides a review of the current analytical requirements for trace-level beryllium analysis for worker protection and also addresses issues that may change those requirements. The current analytical state of the art and relevant challenges facing the analytical community will be presented, followed by suggested criteria for real-time monitoring equipment. Recognizing and addressing these challenges will present opportunities for laboratories, research and development organizations, instrument manufacturers and others.  相似文献   

2.
The Tsurumi, a class-one Japanese river, has a significant metal loading originating from urban environment. Water and sediment samples were collected from 20 sites in winter and summer, 2009 and were analyzed to determine and compare the extent of different trace element enrichment. A widely used five-step sequential extraction procedure was also employed for the fractionation of the trace elements. Concentrations of zinc, copper, lead, chromium, and cadmium were three to four times higher than that of reference values and downstream sediments are much more polluted than the upstream sites. Geochemical partitioning results suggest that the potential trace metal mobility in aquatic environment was in the order of: cadmium > zinc > lead > copper > cobalt > chromium > molybdenum > nickel. About 80.2% zinc, 77.9% molybdenum, 75.3% cobalt, 63.7% lead, 60.9% copper, 55.1% chromium, and 39.8% nickel in the sediment were contributed anthropogenically. According to intensity of pollution, Tsurumi river sediments are moderately to heavily contaminated by zinc, lead, and cobalt. Enrichment factor values demonstrated that zinc, lead, and molybdenum have minor enrichment in both the season. The pollution load index (PLI) has been used to access the pollution load of different sampling sites. The area load index and average PLI values of the river were 7.77 and 4.93 in winter and 7.72 and 4.89 in summer, respectively. If the magnitude of pollution with trace metal in the river system increases continuously, it may have a severe impact on the river’s aquatic ecology.  相似文献   

3.
Uses of pesticides and related agrochemicals have been regulated in the United States since 1948. The United States government has supported human and environmental monitoring for pesticides and selected toxic chemicals for the past 15 yr. The initial ambient monitoring systems were designed to determine average concentrations of pesticides and related chemicals in human and environmental media on a nationwide basis and determine changes in these concentrations over time. The results of these surveys showed that almost all of the general human population and various environmental components contained low concentrations of chlorinated pesticides. As the Environmental Protection Agency (EPA) restricted many uses of the chlorinated pesticides, the organophosphorous and carbamate pesticides which replaced them were not as easily monitored by ambient surveys. Special monitoring studies had to be done more frequently to produce data on these compounds which were not as persistent or accumulative in the environment. Currently, a re-evalution has begun to determine pesticide monitoring data needs for the next 5 to 10 yr, modify existing ambient surveys, and plan needed short-term studies to efficiently meet regulatory data needs. Ambient monitoring for trends in chemical levels in humans and the environment will continue in the United States at a reduced level, and many exposure data needs will be met with use-specific monitoring studies.Presented at the International Conference on Environmental Hazards of Agrochemicals in Developing Countries, 8–12 November, 1983 in Alexandria, Egypt.  相似文献   

4.
5.
我国环境污染治理投资的发展及存在问题   总被引:3,自引:2,他引:1  
环境污染治理投资对于改善我国环境状况,遏制环境污染发展趋势具有重要作用.在界定了环境污染治理投资统计范围之后对我国环境污染治理投资的发展历程、投资结构进行了具体分析,其中重点分析了我国工业污染源治理投资的发展过程和投资结构,总结了我国环境污染治理投资存在的问题,以供决策部门参考.  相似文献   

6.
Regional branches of the Czech Agricultural and Food Inspection participated in the data collection of contaminant agents in processed food and plant raw materials. The project was managed within the framework of the Governmental programme for environmental care in the Czech Republic. The data have been collected since 1984. PC data computering started in 1992 and was used to determine places of occurrence in map form.  相似文献   

7.
通过在西安市三环内6个功能区布设62个采样点,采样分析其表层土壤中邻苯二甲酸酯(PAEs)质量比及其构成特征。结果表明,西安市表层土壤中DMP、DEP、BBP、DnBP、DEHP和DnOP平均值分别为0.188 mg/kg、0.187 mg/kg、0.091 mg/kg、4.174 mg/kg、6.122 mg/kg和0.188 mg/kg,6种PAEs总质量比(∑6PAEs)范围为1.54 mg/kg^153.17 mg/kg,平均值为10.95 mg/kg。6个功能区∑6PAEs从高到低为交通区>工业区>混合区>公园>文教区>住宅区。与其他城市表层土壤中PAEs值比较发现,DMP处于高水平,DEP、DnBP、DEHP和∑6 PAEs处于较高水平,BBP和DnOP处于中等水平。  相似文献   

8.
利用单因子指数法和综合污染指数法,对乌鲁木齐市水磨河4个监测断面水质情况进行了评价。结果表明:搪瓷厂泉为超标水体;七纺桥为Ⅴ类水体,达到农业灌溉用水要求;联丰桥断面、米泉桥断面为劣Ⅴ类水体,没有达到农业灌溉用水要求。生活源和工业源化学需氧量、氨氮等污染物的排入对水体产生了严重影响,造成水体重污染。  相似文献   

9.
The purpose of this study was to investigate the occurrence ofhigh levels of pesticides in groundwater and rainwater in TheProvince of Limburg in The Netherlands. In groundwater samplesin particular the presence of triazines – atrazine, simazine and propazine – was observed; besides these pesticides, dieldrin has also been observed. Atrazine and simazine were found to exceed the groundwater standard of 100 ng L-1. In the rainwater samples, the presence of 13 of 23 different analyzed pesticides was observed. A number of pesticides werefound in high concentrations; e.g. atrazine (>200 ng L-1). Two pesticides detected in rainwater (+-HCH and atrazine) were found to exceed the groundwater standard. Seven pesticides in rainwater were found to exceed the target value and three pesticides the maximum tolerable risk value (DDT, heptachlor and heptachlorepoxide A), which are used as ecotoxicological standards in The Netherlands.Nitrate in 15 of 16 analyzed natural springs was found toexceed the guideline value for nitrate in drinking waterof 50 mg L-1, up to levels of about 200 mg L-1. Nitrate concentrations in rainwater samples were observed up to 4.5 mg L-1. A risk analysis of exposure to high pesticide levels in groundwater or rainwater has been performed using the model HESP. For atrazine levels due todeposition of rainwater in two different locations, exceedance of the T.D.I. level of 0.5 g kg-1 day-1 based on WHO criteria was observed for children using both an urban and a rural scenario and use of groundwater as drinking water.  相似文献   

10.
环境执法难、难执法的现象在我国普遍存在,本文结合乌鲁木齐市环境行政执法的现状,总结和分析了环境执法中所存在的问题及影响执法难的原因,并提出了进一步强化环境执法的对策和建议。  相似文献   

11.
Monte Carlo simulations were performed using the GEANT4 code for the investigation of γ-ray absorption in water in different spherical geometries and of the efficiency of a NaI(Tl) detector for different radionuclides in the aquatic environment. In order to test the reliability of these simulations, experimental values of the NaI(Tl) detector efficiency were deduced and seem to be in good agreement with the simulated ones. In addition, using the simulated efficiency, an algorithm was developed to determine the minimum detectable activity in becquerels per cubic meter in situ as a function of energy for typical freshwater and seawater spectra.  相似文献   

12.
为研究于桥水库浮游植物群落结构及其与环境因子的关系,于2014年春夏季进行采样分析。两季共鉴定出浮游植物6门99种,其中绿藻门(Chlorophyta)62种,硅藻门(Diatoms)21种,蓝藻门(Cyanophyta)7种,裸藻门(Euglenophyta)4种,甲藻门(Pyrrophyta)2种,隐藻门(Cryptophyta)2种。春季浮游植物6门86种,第一优势种为绿藻门的四尾栅藻(Scenedesmus quadricauda);夏季浮游植物5门62种,第一优势种为蓝藻门的铜绿微囊藻(Microcystis aeruginosa)。春季浮游植物密度低于夏季,于桥水库浮游植物群落结构具有明显的季节变化规律。RDA分析结果表明,春季采样点的相似性高于夏季,透明度、水温、溶解氧和营养盐是影响于桥水库浮游植物群落组成的关键环境因子。  相似文献   

13.
While many government policies stimulating deforestation have been reversed, private sector lobbies for uncontrolled logging and soybean export corridors threaten the Amazon. Under a favorable scenario (macroeconomic stabilization, controlled logging and road building, sustainable technologies, global environmental markets) reconversion of natural habitat could be 30% lower than under unfavorable policies and technologies, without sacrificing production.  相似文献   

14.
The occurrence of organotins in the Yangtze River and the Jialing River in the urban section of Chongqing, China and their impact on drinking water waterworks are reported in this study. Water samples were extracted by solid-phase microextraction and measured using a gas chromatograph with mass spectrometer. The results showed that the rivers studied were polluted by both butyltins and phenyltins and that the butyltin species was the dominant pollutant. Butyltins, especially monobutyltin, were detected in all 18 sampling stations, and phenyltins were detected only in 11 sampling stations. Majority of the organotins were MBTs with concentrations varying from 27.3 to 1,145.8 ng Sn L?1. Diphenyltin and dibutyltin were the second most common with the highest levels of 113.7 and 202.5 ng Sn L?1, respectively. Monophenyltin, tributyltin, and triphenyltin had the lowest detection rates with concentration levels of 9.7, 161.8, and 37.2 ng Sn L?1, respectively. Some of the organotins were also detected in drinking water waterworks, which posed a threat to the water quality of Chongqing.  相似文献   

15.
Environmental pollution is one of the major problems being facedtoday due to the advent of extensive industrialization. Heavy metals are the most important contaminants in wastewater that are present in abundance and are toxic. Heavy metal contentsof sewage in the industrial estate of Aligarh (U.P.) have beendetermined by atomic absorption spectrophotometry. The analysisof samples collected from six different locations revealedsignificantly high levels of Fe, Zn, Cu, Cr and Ni. Certainbacteriological (Total bacterial count, Total coliform, Fecal coliform, and Fecal Streptococci) parameters of domestic and industrial sewage as well as soils were monitored from March1990 to January 1993. Total bacterial count, total coliform,fecal coliform and fecal streptococci were found to be lowestin all the samples of industrial wastewater compared to thosein domestic sewage and soil systems. The soil however, contained highest total culturable bacterial population. In view of the common practice of the application of sewage to agricultural land in the neighbouring area, the discharge ofindustrial wastewater without proper treatment into public sewers should be strictly prohibited.  相似文献   

16.
2022年春季,受新一轮新冠疫情影响,长三角各城市采取了一系列管控措施,使得大气污染物排放水平降低。对2022年春季(3—5月)南京及长三角地区的六项污染物尤其是臭氧(O3)的变化特征进行了分析,从气象因素和O3前体物方面,同时利用基于观测的模型(OBM)对南京O3污染变化原因进行了研究,并分析了南京挥发性有机物(VOCs)的关键活性组分和来源。结果表明:2022年春季,南京PM2.5、PM10、NO2和CO均值浓度均同比下降,但O3日最大8 h滑动平均质量浓度(O3-8 h)同比上升19.8%,O3-8 h超标时间同比增加9 d;长三角区域O3-8 h同比上升17.9%,O3-8 h超标天数为2021年同期的2.5倍。南京O3浓度上升的原因:一方面是由于不利的气象条件,另一方面是由于南京O3生成处于VOCs控制区,但氮氧化物(NOx)降幅大于VOCs降幅,同时结合O3前体物削减方案的分析结果发现,VOCs和NOx不当的削减比例会导致O3浓度不降反升。南京O3生成的关键VOC活性物种依次为乙醛、丙烯、间/对二甲苯、丙烯醛和乙烯;正定矩阵因子分解(PMF)解析结果显示,机动车尾气是南京城区VOCs的主要来源,其次为液化石油气/天然气使用和石油化工。  相似文献   

17.
  1. Scientific grounds and the concept of monitoring as the system for observations, assessment and prediction of man-induced changes in the state of natural environment, the program and aims of the background monitoring were developed by the author in 1972–1980. These questions were discussed in detail at the International Symposium on Global Integrated Monitoring (Riga, U.S.S.R., December, 1978). It should be stressed that along with significant anthropogenic loading on large cities and industrial areas, natural ecosystems covering most of the Earth's territory are also exposed to quite extended, though insignificant anthropogenic effects. This paper proposes to consider the ways of the background information use for the biosphere state assessment and prediction.
  2. Classification of objects for monitoring from the point of view of the consequences of the man-made impact, pollution in the first hand, is as follows:
  3. population (public health);
  4. ecosystem elements employed by man whose production is used by population (soil, water bodies, forest, etc.);
  5. biotic elements of ecosystems (without the immediate consumed production);
  6. abiotic constituents of natural ecosystems, considerable components of the biosphere, climatic system.
  7. Historically, monitoring in all countries involves the first two spheres. The background monitoring also extends on the next two spheres. It should differentially take into account physical, chemical and biological factors of impacts. Indentification of biological effects is most complex and vital. Human impact at the background level proceeds indirectly through a general (global or regional) deterioration of the state of the biosphere.
  8. Gradually the background monitoring is being practiced on a larger and larger scale. It is shown that the long-range atmospheric transport of pollutants in various regions leads to a gradual general increase of all the natural media pollution and to perceptible biological effects (soil and water acidification and resulting disturbances in the composition of soil and water organisms). The levels of the background impact differ. Thus, the background concentrations of a number of anthropogenic pollutants in Central Europe is 10–20 times higher than in Central Asia.
  9. The area of priority in the background monitoring of the biosphere pollution has become evident: compounds of sulphur, mercury and their derivatives, organochloride pesticides, some radioactive substances (e.g., krypton-85 in the atmosphere).
  10. The World Ocean is practically all contaminated on a global scale. Biological effects of the World Ocean pollution cause special concern. Particularly important consequences, including climate impact, may be caused by disturbances in energy and matter transfer between environmental media (water-air, water-bottom, etc.). The priority of the impact factors can be allocated here as well: oil products, metals, organochloride compounds, polycyclic aromatic hydrocarbons.
  11. One of the most effective possibilities of environmental quality control is standardization which consists in elaboration of permissible ecological loadings upon ecosystems and natural media. The approach to ecological standardization differs from that of hygienic control in principle. The objective of ecological standardization is to ensure the integrity of the given ecosystem and natural environment on the whole.
  12. Ecological standardization in its turn requires knowledge related to the damage from this or another impact because in such a case there is a possibility to compare ecological standards for the same ecosystem in the case when impacts are of different origin (e.g., different pollutants).
  相似文献   

18.
调查了2009年枯水期和丰水期胶州湾河流入海口和污水处理厂排污口壬基酚污染状况,并初步估算了胶州湾陆源壬基酚的入海通量。结果显示,入胶州湾各河流水体中壬基酚浓度差异较大,枯水期和丰水期分别为0.11~3.17 μg/L和0.09~10.8 μg/L,其中墨水河污染最为严重,其次为娄山河、海泊河、跃进河、李村河、大沽河、镰湾河和白沙河,而洋河污染则相对较轻;各污水处理厂出水口壬基酚浓度相对稳定,枯水期和丰水期为0.11~0.17 μg/L和0.15~0.29 μg/L。枯水期和丰水期胶州湾壬基酚入海通量分别为6.5 kg/d和11.8 kg/d。  相似文献   

19.
Fishers’ local ecological knowledge (LEK) is an additional tool to obtain information about cetaceans, regarding their local particularities, fishing interactions, and behavior. However, this knowledge could vary in depth of detail according to the level of interaction that fishers have with a specific species. This study investigated differences in small-scale fishers’ LEK regarding the estuarine dolphin (Sotalia guianensis) in three Brazilian northeast coastal communities where fishing is practiced in estuarine lagoons and/or coastal waters and where dolphin-watching tourism varies from incipient to important. The fishers (N?=?116) were asked about general characteristics of S. guianensis and their interactions with this dolphin during fishing activities. Compared to lagoon fishers, coastal fishers showed greater knowledge about the species but had more negative interactions with the dolphin during fishing activities. Coastal fishing not only offered the opportunity for fishers to observe a wider variety of the dolphin’s behavior, but also implied direct contact with the dolphins, as they are bycaught in coastal gillnets. Besides complementing information that could be used for the management of cetaceans, this study shows that the type of environment most used by fishers also affects the accuracy of the information they provide. When designing studies to gather information on species and/or populations with the support of fishers, special consideration should be given to local particularities such as gear and habitats used within the fishing community.  相似文献   

20.
综述了美国核电厂辐射环境监测管理体系和环境信息公开制度及法制化管理模式,对比分析了我国辐射环境监测与信息发布实际开展情况及存在问题,提出需借鉴美国核管理委员会(NRC,以下简称NRC)的管理经验,进一步完善我国辐射环境监测标准体系,建立辐射环境监测数据公开制度,加强公众参与制度建设,明确核电厂辐射环境监测管理边界等建议。  相似文献   

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