Biological monitoring versus air monitoring strategies in assessing environmental-occupational exposure

Assessment of environmental and occupational exposure to chemicals can be performed with environmental monitoring (EM) and biological monitoring (BM). Biological monitoring was for a long time considered as a method complementary to environmental monitoring. At present this attitude is changing and in certain areas biological monitoring is applied as the method of choice for exposure and health-risk assessment. This paper examines advantages and disadvantages of those two approaches. In occupational settings environmental monitoring of exposure to VOCs seems to be superior to biological monitoring (possibility of simultaneous determination of components of mixtures, simple interpretation, possibility of evaluation of short-term exposure to local irritants). In the case of this group of compounds BM can be useful in selected cases such as evaluation of dermal absorption or efficiency of protective measures. In the case of metals both forms of monitoring can be used depending on the available methods for interpretation of results. BM of exposure may be considered as superior for evaluating the effects of exposure to lead, cadmium and mercury. However, quantitative evaluation of cancer risk after exposure to arsenic or chromium is possible only on the basis of determination in the air and the use of unit risk values. Both environmental and biological monitoring are useful for evaluation of occupational and environmental exposure to polycyclic aromatic hydrocarbons (PAHs). In certain areas such as evaluation of exposure to external tobacco smoking, cytostatic drugs, and pesticides, biological monitoring is the method of choice used for individual exposure assessment or tracing the trends of environmental exposure.     

环境空气质量自动监测系统管理

针对目前我国监测站环境空气自动监测的发展和管理现状,建立健全城市环境空气自动监测的管理制度和相应的技术档案十分必要。     

Multi-objective optimization of air quality monitoring

A new method for multi-objective optimization of air quality monitoring systems based on satellite remote sensing of the troposphere is described in this work. The technique uses atmospheric turbidity as surrogate for air pollution loading. Through inverse chemical modeling and ancillary information the respective patterns of primary gaseous and particle pollutants are inferred. The optimization algorithm uses the resulting maps of ambient air pollution as input. It focuses on the gain of information with regard to human exposure to high pollution, potential impact on cultural heritage, compliance to ambient air quality standards, monitoring key point and area source emissions, as well as on the associated cost. Application of the method in Brescia, Italy showed its significant potential for improving the cost-effectiveness of air quality monitoring networks at the urban and regional scales.     

Microsoft Word for Windows在环境质量报告书中的应用

叙述了ＭｉｃｒｏｓｏｆｔＷｏｒｄｆｏｒＷｉｎｄｏｗｓ软件在编写环境质量报告书中的应用内容。     

Calibration of two passive air sampler configurations for monitoring concentrations of hexabromocyclododecanes in indoor air

While polyurethane foam (PUF) disk passive air samplers are employed increasingly to monitor persistent organic pollutants in indoor air, they essentially sample only the vapour phase. As a previous investigation of the vapour : particle phase partitioning of hexabromocyclododecanes HBCDs in (outdoor) air reported them to be present largely in the particulate phase, we monitored three offices using active air samplers. In each, approximately 65% of HBCDs were present in the vapour phase, suggesting PUF disk passive samplers are suitable for monitoring HBCDs in indoor air. Concentrations in the three offices (239-359 pg Sigma HBCD m(-3)) exceed substantially those reported in outdoor air from the United States (2.1-11 pg Sigma HBCD m(-3)), but are in line with outdoor air from Stockholm. The relative abundance of the three principal diastereomers in office air was closer to that found in technical HBCD formulations (i.e. predominantly gamma-HBCD) than in most US outdoor air samples. Time integrated air concentrations of alpha-, beta-, and gamma-HBCD were obtained for an office using a low volume sampler operated over a 50 d period alongside PUF disk samplers. This calibration exercise yielded the following passive air sampling rates for both a fully- and part-sheltered PUF disk sampler design: for alpha-, beta-, and gamma-HBCD, 0.87, 0.89, and 0.91 m3 d(-1) respectively (fully-sheltered) and 1.38, 1.54, and 1.55 m3 d(-1) respectively (part-sheltered). Deployment of the part-sheltered configuration yielded concentrations approximately 35% lower than those obtained using a high volume sampler, consistent with PUF disk samplers measuring primarily the vapour phase.     

Solvent-free sampling with di-n-butylamine for monitoring of isocyanates in air

The solvent-free sampler for airborne isocyanates consisted of a polypropylene tube with an inner wall coated with a glass fibre filter, coupled in series with a 13 mm glass fibre filter. The filters were impregnated with reagent solution containing equimolar amounts of di-n-butylamine (DBA) and acetic acid. Air sampling was performed with an air flow of 0.2 l min(-1). The formed isocyanate-DBA derivatives were determined using liquid chromatography and tandem mass spectrometry. The sampler was investigated in regard to collection principle and extraction of the formed derivatives with good results. The possibility to store the sampler before sampling and to perform long-term sampling was demonstrated. Field extraction of the sampler was not necessary, as there was no difference between immediately extracted samples and stored ones (2 days). In comparative studies, the sampler was evaluated against a reference method, impinger-filter sampling with DBA as reagent. The ratios between the results obtained with the sampler and the reference in a test chamber at a relative humidity (RH) of 45% was in the range of 83-109% for isocyanates formed during thermal decomposition of PUR. At RH 95%, the range was 72-101% with the exception of isocyanic acid. In two field evaluations, the ratios for fast curing 2,4'- and 4,4'-methylene bisphenyl diisocyanate (MDI) was in the range 81-113% and for the 3-ring MDI the range was 54-70%. For the slower curing 1,6-hexamethylene diisocyanate (HDI) and HDI isocyanurate, the ratios were in the range 78-145%. In conclusion, the solvent-free sampler is a convenient alternative in most applications to the more cumbersome impinger-filter sampler.     

Preliminary air pollution monitoring in San Miguel, Buenos Aires

Passive diffusion samplers were employed in San Miguel(Buenos Aires Metropolitan Area) for a preliminary airpollution monitoring. The highest loads were observedin downtown, compared with an urban background site.Total suspended particulate matter (TSPM) varied from0.257 to 0.033 mg cm^-2 month^-1; dust was examinedfor particle nature and size distribution. A similartrend was observed for nitrogen dioxide (NO₂) andTSPM spatial distribution, suggesting that traffic isthe major pollution source. Sulphur dioxide (SO₂)values were low and rather homogeneous. Levels for theinvestigated pollutants are below EPA's guide linevalues. Geographic (flat area, near to Rio de LaPlata) and climatologic factors (rainfalls andvariable wind directions) contribute to disperse pollutants.     

Long-term phenol, cresols and BTEX monitoring in urban air

This paper reports the results of a long-term monitoring of benzene, toluene, ethylbenzene, xylenes (BTEX), phenol and cresols in the air of Padua during a wide period of the year 2007 using two radial passive samplers (Radiello system) equipped with BTEX- and phenol-specific cartridges. Two sites were monitored, one in the industrial area and one close to the town centre. Relevant pollution episodes have been observed during both the winter and summer periods. Benzene, together with toluene, ethylbenzene and xylenes showed their maximum concentrations during the winter season, but the secondary pollutant phenol was higher than benzene for a large period of the year when the meteorological conditions blocked the pollutants in the lower layers of the atmosphere and solar radiation increased the benzene photo-oxidation process.     

区域空气监测网络建设策略与实践

根据区域空气质量管理的发展形势,提出建设区域空气自动监测网络的思路和建设内容,探索建立区域空气监测QA/QC技术体系的策略与解决方案。     

The design of cost-effective air quality monitoring networks

A statistical measure of information content is used as a means for assessing the effectiveness of a particular monitoring network configuration. This measure is directly related to the precision with which the network can estimate the level of air quality in the region. Each potential site in the network can contribute to an increase in the overall precision of the estimate. The amount of increase is determined by the degree of dependence, displayed by observed pollutant concentrations, between potential sites.A statistical procedure is used to combine the observed pollution dynamics and the measurement network in order to assess network effectiveness. An iterative application of this procedure leads to the design of the most effective network subject to a specified budget constraint.     

中国环境空气质量监测现状与发展

中国的环境空气质量监测经过20多年的发展,已经进入到自动监测阶段。完善城市空气自动监测系统、区域监测系统、质量保证、质量控制和监测项目,以及实现地级以上城市空气质量预报等是下一阶段的主要发展目标。     

长光程大气自动监测中异常数据的分析及处置

长光程大气自动监测系统部件较多,结构复杂,中心站对子站监控通过在线方式完成,因此对系统中故障的判断和排除有一定难度。通过对中心站调出的异常数据进行诊断和分析,帮助操作者提升对系统的了解和对异常数据处理的技能。     

环境空气自动监测故障与维修特例

介绍了空气自动监测系统氮氧化物分析仪工作原理 ,对光电倍增管室温度控制系统故障产生的原因及解决方法进行了详细阐述     

Urgent problems of improving background air pollution monitoring systems

For more than 12 years, systematic observations of background air pollution have been carried out in accordance with the WMO Programme using the network of USSR stations located in sparsely populated settlements and in a number of neighbouring cities. The parameters involved include spectral radiation measurements, determination of chemical composition of precipitation and the concentrations of a number of atmospheric pollutants. Analysis of the data obtained allows conclusions to be drawn on the capabilities of the current system and to evaluate methods of improving it.In order to further improve the monitoring system, it is recommended that the system should perform the same observations on air pollution and precipitation as carried out by other international and national programs, and also to create centralized laboratories to deal with the analysis of samples from these monitoring stations. Additionally, solid sorbents are emerging as an effective means of sampling certain air pollutants. They may be sent by post, they increase the accuracy of measurements and allow air sampling intervals of up to 7–10 days, thus synchronizing this period with the interval of precipitation sampling.     

Air pollution exposure monitoring and estimating. Part I. Integrated air quality monitoring system

This paper presents an integrated exposure monitoring system, based on an expansion of existing air quality monitoring systems using dispersion modelling. The system allows: (1) identifying geographical areas whose inhabitants are most exposed to ambient pollution; (2) identifying how many people in an area are exposed to concentrations of pollution exceeding air quality guidelines; (3) describing the exposure of population subgroups (e.g. children); (4) planning pollution abatement measures and quantifying their effects; (5) establishing risk assessment and management programs, and (6) investigating the short- and long-term effects of both pollutants and pollution sources on public health. The effect of pollution is rarely very large and in order to discover it, exposure estimation must provide data that reflects both spatial and temporal variations. Estimates of pollution exposure are obtained using an integrated approach that combines results of measurements from monitoring programs with dispersion calculations. These values can serve as estimates for individual short-term or long-term exposure. The grouped data allows the expression of ambient pollution concentrations as the spatial distribution of estimates such as the mean or 98th percentile of such compounds as SO2, O3, NO2, PM10 and PM2.5. This integrated approach has been combined into a single software package, AirQUIS.     

An automatic monitor of formaldehyde in air by a monitoring tape method

An automatic monitor has been developed for measuring formaldehyde in air using a sensitive tape for formaldehyde. It is based on the color change of the tape on reaction with formaldehyde. The porous cellulose tape, containing silica gel as an absorbent and impregnated with the processing solution containing hydroxylamine sulfate, Methyl Yellow (pH indicator; pH 2.9-4.0, red-yellow), glycerin and methanol, was found to be a highly sensitive means of detecting formaldehyde and maintains a stable sensitivity. When the tape was exposed to a sample of air containing formaldehyde, the color of the tape changed from yellow to red. The degree of color change was proportional to the concentration of formaldehyde at a constant sampling time and flow rate, and it could be recorded by measuring the intensity of reflected light (555 nm). The tape could be used to detect down to 0.08 ppm (World Health Organization standard) of formaldehyde with a sampling time of 30 min and a flow rate of 100 mL min-1. Reproducibility tests showed that the relative standard deviation of response (n = 10) was 3.8% for 0.1 ppm formaldehyde. The monitor is simple, specific, capable of unattended operation and is recommended for both laboratory and field operation.     

环境空气中多环芳烃的采样与分析技术

文章对环境空气中多环芳烃的采样与分析方法进行了概述,侧重介绍了样品的采集、净化、采样效率的评估方法和采样分析全过程的质量控制.     

Locating air quality monitoring station using wind impact area diagram

In this study a new methodology is suggested to approximate the impact area downwind of an air pollution source, where air quality monitoring can be carried out to capture the maximum pollutant concentration. Hourly wind speed for a given month is grouped in to different wind speed ranges and the distance of pollutant travel is approximated from the average wind speed of that wind speed range. Since change in wind direction causes the impact distance to rotate, its rotation is approximated by the SD of wind direction change. Using this approach, area or region down wind of a source is determined and plotted. The pattern of monthly change of wind is better represented by the new type of diagram as compared to the wind rose diagram.     

相似分析在空气连续监测缺测资料插补处理中的应用

空气连续自动监测中缺测资料的插补处理是环境监测与科研的一项基础性的技术工作,文章应用数理统计中的相似分析原理进行探讨,取得了较理想的结果.该方法对解决和处理因采样时间不足而造成的污染物浓度日均值缺失问题是十分有效的,对目前我国开展的城市空气质量日报工作有一定的实际意义.