Direct on-filter assay of subtilisin-type proteolytic enzymes for rapid analysis of analyte captured from the workplace atmosphere

A simple assay for some proteolytic enzymes has been developed which can be performed directly on the surface of a cellulose nitrate filter used to capture the analyte during workplace monitoring for health and safety purposes. Following air sampling the analysis is performed on the filter which is retained within the air sampler. This involves two steps: first, a 15 min incubation in which the captured enzyme is dissolved and then digests an alkaline-phosphatase-labelled antibody immobilised as a small dot on the surface of the filter; and second, is a 10 min incubation with substrate solution, which follows an in situ wash under a vacuum. During the incubation colour develops on the spot at the location of the immobilised enzyme antibody conjugate. The intensity of the spot can be assessed visually within the sampler to ascertain the presence or absence of captured enzyme, or alternatively quantitative results can be obtained using an optical scanner. The limit of detection is 5 ng per filter for subtilisin (20 ng for visual discrimination between this standard and the zero). The assay is stable to the effects of ambient air sampling at 31 min(-1) for 18 h.     

A real-time monitoring system for Kerava river quality

The hygienic quality of the water of the Kerava river, southern Finland, deteriorates occasionally. The purpose of the study was to design a real-time monitoring system that would inform the public using the river for recreational purposes about the changes in water quality. The system was constrained to consist of on-line sensing of water quality and quantity, and adjacent forecasting models. Four different system alternatives were analyzed and compared. The first alternative observes river flow in real-time; the second alternative also monitors water temperature, turbidity, pH, conductivity and dissolved oxygen. The data collected in this way are used to forecast Streptococcus and E. coli concentrations, using canonical correlation and regression analysis. The third configuration is a two-step procedure, where river flow is first predicted by an ARMAX model and the hygienic state is then based on the flow estimate, as in the first assemblage. The most expensive monitoring system, which at present is the least well-known, is to apply the Lidar system, where the hygienic status of the river quality is observed directly using laser technology, placing less emphasis on modeling. In this paper, the alternatives are formulated and a preliminary comparison is made, using the criteria of operational feasibility, prediction uncertainty, investment and maintenance costs, and suitability for in-situ monitoring.     

Integrated real-time monitoring system to investigate the hypoxia in a shallow wind-driven bay

Corpus Christi Bay (Texas, USA) is a shallow wind-driven bay which experiences hypoxia (dissolved oxygen < 2 mg/L) during the summer. Since this bay is a very dynamic system, the processes that control the hypoxia can last on the order of hours to days. Monitoring systems installed on a single type of platform cannot fully capture these processes at the spatial and temporal scales of interest. Therefore, we have integrated monitoring systems installed on three different platform types: (1) fixed robotic, (2) mobile, and (3) remote. On the fixed robotic platform, an automated profiler system vertically moves a suite of water quality measuring sensors within the water column for continuous measurements. An integrated data acquisition, communication and control system has been configured on our mobile platform (research vessel) for synchronized measurements of hydrodynamic and water quality parameters at greater spatial resolution. In addition, a high-frequency radar system has been installed on remote platforms to generate surface current maps for the bay. With our integrated system, we were able to capture evidence of a hypoxic event in summer 2007; moreover, we detected low dissolved oxygen conditions in a part of the bay with no previously reported history of hypoxia.     

A method for monitoring ground water quality near waste storage facilities

A practical optimization approach developed in this paper derives effective monitoring configurations for detecting contaminants in ground water. The approach integrates numerical simulation of contaminant transport and mathematical programming. Well sites identified by the methodology can be monitored to establish the occurrence of a contaminant release before a plume migrates to a regulatory compliance boundary. Monitoring sites are established along several horizons located between the downgradient margin of a contaminant source and a compliance boundary. A horizon can form an effective line of defense against contaminant migration to the compliance boundary if it is spanned (covered) by a sufficient number of sites to yield a well spacing that is equal to or less than a maximum value established by numerical modeling. The objective function of the integer programming model formulation expresses the goals of: (1) covering a maximum number of siting horizons, and (2) allocating wells to the single most effective horizon. The latter is determined from well spacing requirements and the width of the zone of potential contaminant migration traversed by the horizon. The methodology employs a highly tractable linear programming model formulation, and the user is not required to predefine a set of potential well sites. These attributes can facilitate its implementation in practice.     

Emission of mercury to the atmosphere from industrial sources in Poland

The emission factors of mercury and calculation of annual emission into the atmosphere from different industrial sources in Poland are presented. The emission factors in turn depend on mercury concentration in raw materials, as well as on the character of a technological process. The combustion of hard coal and lignite was found to be the major emission source of mercury into the atmosphere.     

Utilization of the solid sorbent media in monitoring of airborne cyclophosphamide concentrations and the implications for occupational hygiene

The main objective of the study was to evaluate the applicability of two solid sorbent media (Anasorb 708 and Strata X), the impinger filled with distilled water and PTFE filters for determination of airborne cyclophosphamide (CP) in the hospital working environment. For this purpose, air contamination of Masaryk Memorial Cancer Institute (Czech Republic) was monitored using the sampling apparatus containing the samplers described above. In addition, the surface contamination was also determined using the wipe sampling technique. During the monitoring, contamination of three different workplaces (storage room, preparation room and outpatient clinic) was studied. Using Strata X solid sorbent tubes, airborne CP was determined in all (n = 5) samples collected at the outpatient clinic over a 5 day monitoring period (concentration range: 0.3-4.3 ng m(-3)). Other samplers (including PTFE filters) did not collect any detectable amount of CP (the limit of detection, LOD ≤ 0.1 ng m(-3)). Negative results detected at filter samples indicate that CP determined at Strata X samples was most probably of gaseous origin. Surface contamination ranged from <2 to 19, <8 to 418 and 133-15,500 pg cm(-2) at the storage room, preparation room and outpatient clinic, respectively. The study showed that evaporation of antineoplastic drugs should not be neglected, albeit the concentrations determined in our study are relatively low. Therefore, proper monitoring of airborne contamination should involve simultaneous sampling of both particle-bonded and gaseous phases. In this way, Strata X sorbent tubes seem to be an effective tool for the sampling of gaseous CP in the indoor air.     

环境空气中二氧化硫的自动监测及问题研究

介绍了空气中 SO2 的测定方法脉冲荧光法 ,对有关的问题进行了初步探讨。为正确使用该方法及仪器提供了依据。     

The backend design of an environmental monitoring system upon real-time prediction of groundwater level fluctuation under the hillslope

The groundwater level represents a critical factor to evaluate hillside landslides. A monitoring system upon the real-time prediction platform with online analytical functions is important to forecast the groundwater level due to instantaneously monitored data when the heavy precipitation raises the groundwater level under the hillslope and causes instability. This study is to design the backend of an environmental monitoring system with efficient algorithms for machine learning and knowledge bank for the groundwater level fluctuation prediction. A Web-based platform upon the model-view controller-based architecture is established with technology of Web services and engineering data warehouse to support online analytical process and feedback risk assessment parameters for real-time prediction. The proposed system incorporates models of hydrological computation, machine learning, Web services, and online prediction to satisfy varieties of risk assessment requirements and approaches of hazard prevention. The rainfall data monitored from the potential landslide area at Lu-Shan, Nantou and Li-Shan, Taichung, in Taiwan, are applied to examine the system design.     

Evaluation of a real-time monitoring system for river quality — a trade-off between risk attitudes,costs, and uncertainty

Uncertainty is definitely one of the key topics in environmental assessment and management. Typically, attempts to reduce uncertainty are subject to expenses. But how to compare and trade-off expenses and the reduced uncertainty? They only seldom allow the use of a single unit. Instead, the whole analysis and decision procedure is very subjective. This paper presents one approach to handle such problems, namely the combined use of Bayesian influence diagrams, and probabilistic risk attitude analysis. The approach was used in the evaluation of three alternatives for a real time river water quality forecasting system. A trade-off analysis of risk attitudes, costs and uncertainty indicated the levels of socioeconomic utility required for investments in the respective systems, and accordingly illuminated the impact of the uncertainties involved on inference and decision-making with various risk attitudes and discount rates.     

A proposed coast-wide reference monitoring system for evaluating wetland restoration trajectories in Louisiana

Wetland restoration efforts conducted in Louisiana under the Coastal Wetlands Planning, Protection and Restoration Act require monitoring the effectiveness of individual projects as well as monitoring the cumulative effects of all projects in restoring, creating, enhancing, and protecting the coastal landscape. The effectiveness of the traditional paired-reference monitoring approach in Louisiana has been limited because of difficulty in finding comparable reference sites. A multiple reference approach is proposed that uses aspects of hydrogeomorphic functional assessments and probabilistic sampling. This approach includes a suite of sites that encompass the range of ecological condition for each stratum, with projects placed on a continuum of conditions found for that stratum. Trajectories in reference sites through time are then compared with project trajectories through time. Plant community zonation complicated selection of indicators, strata, and sample size. The approach proposed could serve as a model for evaluating wetland ecosystems.     

Comparison of the suitability of two lichen species and one higher plant for monitoring airborne heavy metals

We compared the capacity to accumulate airborne heavy metals of two lichens (Flavoparmelia caperata and Parmotrema chinense) and one higher plant (Nerium oleander) at a very densely populated urban site near Naples. After 15, 45, 75, and 120 days of exposure at four sites with different levels of air pollution, equal portions of thalli and 20 leaves were collected, and four environmentally significant elements, Fe, Cu, Zn, and Pb, were measured by inductively coupled plasma analysis. To compare the accumulation rates of lichens and the vascular plant, we determined an index of relative accumulation rate of pollutants during time and the ratio between the concentrations of each element in exposed samples to that of control samples (exposed-to-control ratio). Our data indicate F. caperata as being the most suitable bioaccumulator, followed by P. chinense. N. oleander was also found to be a useful heavy metal biomonitor though not suitable as a bioaccumulator.     

A multiresidue method for the analysis of phenols and nitrophenols in the atmosphere

A method using GC-MS and derivatization with N-(t-butyldimethylsilyl)-N-methyltrifluoroacetamide (MTBSTFA) was developed for the analysis of 20 phenolic compounds in atmospheric samples (gas and particles). Air sampling was carried out using a Hi-Vol sampler with glass fibre filter and XAD-2 resin at a flow rate of 60 m(3) h(-1). The particle and gas phases were collected separately over a period of 4 h. Samples were Soxhlet extracted, evaporated to dryness under nitrogen and refilled with acetonitrile. 100 microl of these extracts were derivatized with 100 microl of MTBSTFA at 80 degrees C for 1 h under strong stirring. Phenolic compounds were injected into a GC-MS in splitless mode and quantified as their TBDMS derivatives in the SIM mode. Mass spectral analysis of the derivatives of the 20 compounds studied indicates that the spectra are highly specific showing an ion at [M - 57]+ which is useful for structure confirmation or analysis at low levels using selected ion monitoring. Quantification limits varied between 5 microg l(-1) and 10 microg l(-1) which correspond to 20 pg m(-3) and 40 pg m(-3) for 250 m(3) of air sampled. This method was successfully applied to atmospheric samples.     

A simple method for the extraction of mutagens from airborne particles

Organic materials were extracted with acetone from filters of airborne particles by soaking, shaking, soxhletion, and sonication. These extracts were tested with and without S9 for mutagenicity using Ames assay and arabinose-resistant assay of Salmonella typhimurium. Among the extraction methods, soaking extract had the highest mutagenic activity followed by sonication, shaking, and soxhletion in both the assays. With the samples studied, it was concluded that soaking with acetone for 1/2 hr is the simplest and an efficient procedure for the extraction of mutagens from airborne particles.Results of cooperative investigation of NIOSH and West Virginia Agricultural and Forstry Experimental Station. Published with the approval of the Director of the West Virginia Agricultural and Forestry Experiment Station as Scientific Paper No. 1822.     

The measurement procedure in the SEMONT monitoring system

The measurement procedure of the open area in situ electric field strength is presented, acquiring the real field data for testing of the Serbian electromagnetic field monitoring network (SEMONT) and its Internet portal. The SEMONT monitoring system introduces an advanced approach of wireless sensor network utilization for the continuous supervision of overall and cumulative level of electromagnetic field over the observed area. The aim of the SEMONT system is to become a useful tool for the national and municipal agencies for the environmental protection, regarding the electromagnetic pollution monitoring and the exposure assessment of the general population. Considering the public concern on the potentially harmful effects of the long-term exposure to electromagnetic radiation, as well as the public transparency principle that is incorporated into the Serbian law on non-ionizing radiation protection, the SEMONT monitoring system is designed for the long-term continuous monitoring, presenting real-time measurement results, and corresponding exposure assessment over the public Internet network.     

论中国环境监测技术体系建设

论述了建设和完善环境监测技术体系的重要意义,分析了我国环境监测技术体系的发展现状及问题,提出了建设我国环境监测技术体系的构想。     

大辽河入海口水质在线自动监测系统取样工程的建设与维护

介绍一个以自吸喷射泵为取样泵的水质自动监测系统取样工程建设方案及其日常维护措施。适用于河口和四季分明水域建设水质自动监测站需要,更可在其他类型水域建站时借鉴使用。     

试论环境空气质量自动监测系统的设计

目前 ,我国重点城市都在开展环境空气质量日报或预报工作 ,开展这一工作的基本条件之一是必须建立环境空气质量自动监测系统。由于我国目前的研制水平有限 ,空气质量自动监测系统基本上是靠引进国外技术及设备来完成的。而引进设备往往与我国的具体实际结合不够 ,尤其是在系统结构、数据采集、远程控制与诊断方面同我们的实际要求相去甚远。为此本文将围绕国内环境监测共同关注的环境空气质量自动监测系统及其设计的问题展开讨论 ,内容包括目前国内自动监测系统的现状 ;国外发展情况及趋势 ;自动监测系统结构与要求     

Seasonal characteristics of haze observed by continuous visibility monitoring in the urban atmosphere of Kwangju, Korea

Continuous visibility monitoring has been carried out inKwangju, Korea since May 1999. The total light extinctioncoefficient b _ext measured by a transmissometer andreveals seasonal trends in urban visual air quality,especially under hazy conditions with a visual range of lessthan 15 km. Seasonal atmospheric visibility under lowrelative humidity during the winter was observed to be betterthan during any other seasons. Summertime visibility wasseverely degraded due to highly increased light scattering byhygroscopic particles under high humidity atmosphericconditions. Visibility during spring and fall was alsomoderate. However, yellow sand in spring caused the lowestvisibility conditions over the measurement area for a fewdays. With continuous monitoring using the transmissometer,the daily average seasonal visual range was measured to be13.1, 9.2, 11.0, and 13.9 km in spring, summer, falland winter, respectively. Under the atmospheric humiditycondition less than 60%, visual range was observed tobe 16.1, 13.9, 15.1, and 16.6 km in spring, summer,fall, and winter, respectively. The mean light extinctionbudget by sulfate and nitrate aerosols was determined to bethe highest value of 63.71% during the summer and thelowest value of 27.08% during spring. During the `yellow sand dust' period, a mean light extinction budget by soil particles was estimated to be at an unusually high value of 44.22%.     

A new protease assay system using gelatin thin film for monitoring indoor air quality

Airborne particulates have a major influence on the quality of indoor environments, which in turn affects human health. Both allergens and proteases are major etiological factors in allergic disease. Thus, the monitoring of environmental protease particulates is very important for the management of allergic disease. Protease-monitoring systems have been introduced in industry, but have not been applied to domestic settings, probably because of the high cost and many complex steps involved in these systems. In this study, we developed an indoor protease-monitoring system which can easily detect protease particulates without need for pre-treatment of dust samples or complex measuring instruments such as fluorescent plate reader. As a protease substrate, gelatin thin film (GTF) was adopted to evaluate small amounts of house dust particulates. The principle of this assay is based on the hydrolysis of GTF. Protease molecules spread from a particulate to GTF can hydrolyze the gelatin, thereby producing a spot on the GTF. This hydrolyzed spot visualized by staining was much larger than the particulate size, making visible to naked eye. The GTF method facilitated the observation of a subtle increase in protease particulates fallen on the GTF after the turnover of a used bed-quilt. The newly developed GTF method seems to be a suitable tool for protease monitoring at home.