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141.
The Bhopal disaster in India in 1984 has compelled manufacturing companies to review their operations in order to minimize their risk exposure. Much study has been done on the subject of risk assessment and in refining safety reviews of plant operations. However, little work has been done to address the broader needs of decision makers in the multinational environment. The corporate headquarters of multinational organizations are concerned with identifying vulnerable areas to assure that appropriate risk-minimization measures are in force or will be taken. But the task of screening global business units for safety prowess is complicated and time consuming. This article takes a step towards simplifying this process by presenting the decisional model developed by the authors. Beginning with an overview of key issues affecting global safety management, the focus shifts to the multinational vulnerability model developed by the authors, which reflects an integration of approaches. The article concludes with a discussion of areas for further research. While the global chemical industry and major incidents therein are used for illustration, the procedures and solutions suggested here are applicable to all manufacturing operations.  相似文献   
142.
Habitats or environmental factors that convey spatial and temporal resistance and/or resilience to biotic communities that have been impacted by biophysical disturbances may be called refugia. Most refugia in rivers are characterized by extensive coupling of the main channel with adjacent streamside forests, floodplain features, and groundwater. These habitats operate at different spatial scales, from localized particles, to channel units such as pools and riffles, to reaches and longer sections, and at the basin level. A spatial hierarchy of different physical components of a drainage network is proposed to provide a context for different refugia. Examples of refugia operating at different spatial scales, such as pools, large woody debris, floodplains, below dams, and catchment basins are discussed. We hope that the geomorphic context proposed for examining refugia habitats will assist in the conservation of pristine areas and attributes of river systems and also allow a better understanding of rehabilitation needs in rivers that have been extensively altered.  相似文献   
143.
This paper describes the use of a Fourier transfer infrared (FTIR) spectrometer, integrated with a sampling system and a control software, as a continuous emission monitor (CEM) for on-line measurement of most volatile organic and some inorganic compounds from various gas emissions. The time response of the system was tested experimentally, and can be approximated by a complete mixing model. In order to validate the measurement accuracy of the system, spiking tests are suggested. This paper discusses considerations in designing the spiking test and analyzing the spiking results. Field test results show that the FTIR-CEM has a stable performance and can be applied to stack emission monitoring, process monitoring, and unknown HAPs identification in many thermal treatment processes.  相似文献   
144.
Asthmatic and nonasthmatic families in a representative community population sample have been monitored over a 2-year period using daily diaries. Simultaneous micro-indoor and outdoor monitoring has been conducted in a representative sample of houses for air pollutants, pollen, fungi, algae, and climate. Macromonitoring of air pollutants and pollen was conducted simultaneously. The relationship of indoor to outdoor and micro to macro factors can be demonstrated. Acute symptoms were strongly related to age, weakly related to sex, and not related to smoking habits. The qualitative relationship of these micro and macro factors to symptoms in asthmatic and nonasthmatic families have been explored. Suspended particulate matter and pollen were related to symptoms in asthmatics and nonasthmatics. Fungi might be related to symptoms as well. The use of gas stoves is qualitatively related to symptoms. Algae and other contaminants of evaporative coolers do not appear to be important in producing symptoms. More complex statistical analyses are required to determine interactions of these factors. Distinction has to be drawn between infectious episodes, allergic episodes, nonallergic but similar episodes, and asthmatic attacks. This study demonstrates the need for further investigations in this area.  相似文献   
145.
The aim of this work was to report on imidacloprid [IUPAC name 1-(6-chloro-3-pyridylmethyl)-N-nitroimidazolidin-2-ylideneamine] residues in some vegetables, fruits, and water samples collected from the West Bank, Palestine, in 1998 and 1999. Imidacloprid and its derivatives in the study samples were extracted by methanol/water and oxidized into 6-chloronicotinic acid and subsequently derivatized into 6-chloronicotinic acid trimethylsilyl ester before being determined by GC/MS. Imidacloprid residues were detected in more than half of the analyzed samples. The highest and lowest imidacloprid concentrations were found in eggplant (0.46 mg/kg) and green beans (0.08 mg/kg), respectively. An increase of 11–120% in imidacloprid concentration in the 1999 samples was observed when compared with those of 1998. This may suggest imidacloprid accumulation in the soil and/or increased use by local farmers. The imidacloprid residue concentrations in several crops were found to exceed the CODEX maximum residue limit.  相似文献   
146.
Organic matter (OM) remineralization may be considered a key function of the benthic compartment of marine ecosystems and in this study we investigated if the input of labile organic carbon alters mineralization of indigenous sediment OM (OM priming). Using 13C-enriched diatoms as labile tracer carbon, we examined shallow-water sediments (surface and subsurface layers) containing organic carbon of different reactivity under oxic versus anoxic conditions. The background OM decomposition rates of the sediment used ranged from 0.08 to 0.44 μmol C mlws−1 day−1. Algal OM additions induced enhanced levels of background remineralization (priming) up to 31% and these measured excess fluxes were similar to mineralization of the added highly degradable tracer algal carbon. This suggests that OM priming may be important in marine sediments.  相似文献   
147.
The radiation doses to humans resulting from a potential release of radionuclides from a geological repository for long-lived waste are assessed over tens or even hundreds of thousands of years. Ingestion is expected to be the major exposure pathway, and the group with the highest exposures will be those that consume the most contaminated food. In this paper, we characterize the group of individuals with the highest exposures by considering the physical and biological characteristics of the contaminated area and human requirements for energy and nutrients. We then calculate intake rates based on land-use scenarios drawn from self-sustained communities spanning prehistoric times to an industrial-age agrarian culture. The approach is illustrated by simulating groundwater release of four radionuclides to an expected discharge area. We argue that the derived intake rates may serve as credible bounding cases when projected doses are evaluated for compliance with regulatory criteria.  相似文献   
148.
Previous studies have evaluated associated health risks and human exposure pathways at mining sites. Others have provided estimates of the scale of the issue based in part on surveys. However, a global census of mining-related hazardous waste sites has been lacking. The Toxic Sites Identification Program (TSIP) implemented by Blacksmith Institute (New York, NY, USA) since 2009 is an ongoing effort to catalogue a wide range of chemically contaminated sites with a potential human health risk (Ericson et al., Environ Monit Assess doi:10.1007/s 10661-012-2665-2, 2012). The TSIP utilizes a rapid assessment instrument, the Initial Site Screening (ISS), to quickly and affordably identify key site criteria including human exposure pathways, estimated populations at risk, and sampling information. The resulting ISS allows for comparison between sites exhibiting different contaminants and pollution sources. This paper explores the results of a subset of ISSs completed at 131 artisanal and small-scale gold mining areas and 275 industrial mining and ore processing sites in 45 countries. The authors show that the ISS captures key data points, allowing for prioritization of sites for further investigation or remedial activity.  相似文献   
149.
Panel Discussion     
A stack design procedure is developed which accounts for the effect of plume interception by downwind buildings, and which provides information on effluent concentrations in a form useful to planning authorities. The information presented in this paper is directed to engineers carrying out stack designs for locations where downwind buildings are of comparable height to the stack. A wind tunnel investigation using tracer gas techniques indicates that, for a plume at building height, downwash on the upwind face of a building causes the high concentrations observed near the roof to be transported to ground level. The effect of a plume on elevated points is determined by the concept of the minimum descent height of the maximum allowable ambient concentration isopleth. This minimum descent height, computed using Gaussian plume dispersion theory, defines a building height below which pollutant concentrations will always lie within safe limits. A case study is presented for the use of the design procedure for a small thermal power plant in an urban area.  相似文献   
150.
Title I of the Clean Air Act Amendments of 1990 calls for “enhanced monitoring” of ozone, which is planned to include measurements of atmospheric non-methane organic compounds (NMOCs). NMOC concentration data gathered by two methods in Atlanta, Georgia during July and August 1990 are compared in order to assess the reliability of such measurements in an operational setting. During that period, automated gas chromatography (GO) systems (Field systems) were used to collect NMOC continuously as one-hour averages. In addition, canister samples of ambient air were collected on an intermittent schedule for quality control purposes and analyzed by laboratory GC (the Lab system). Data from the six-site network included concentrations of nitrogen oxides (NOX), carbon monoxide (CO), ozone, total NMOC (TNMOC), and 47 identified NMOCs. Regression analysis indicates that the average TNMOC concentration from the Lab system is about 50 percent higher than that from the Field system, and that the bulk of the difference is due to unidentified NMOCs recorded by the Lab system. Also, there are substantial uncertainties in predicting a single Field TNMOC concentration from a measured Lab concentration. Considering individual identified NMOCs, agreement between the systems is poor for many olefins that occur at low concentrations but may be photochemically important. Regressions of TNMOC against CO and NOX lead to the conclusion that the larger unidentified component being reported by the Lab system is not closely related to local combustion or automotive sources.  相似文献   
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