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251.
In this research, a risk assessment was undertaken in order to develop the remediation and management strategy of a contaminated gunnery site, where a nearby flood controlling reservoir is under construction. Six chemicals, including explosives and heavy metals, posing potential risk to environmental and human health, were targeted in this study. A site-specific conceptual site model was constructed, based on effective, reasonable exposure pathways, to avoid any overestimation of the risk. Also, conservative default values were adapted to prevent underestimation of the risk when site-specific values were not available. The risks posed by the six contaminants were calculated using the API’s Decision Support System for Exposure and Risk Assessment, with several assumptions. In the crater-formed-area (Ac), the non-carcinogenic risks (i.e., HI values) of tri-nitro-toluene (TNT) and Cd were slightly larger than 1, but for RDX (Royal Demolition Explosives) was over 50. The total non-carcinogenic risk of the whole gunnery range was calculated to be 62.5, which was a significantly high value. The carcinogenicity of Cd was estimated to be about 10−3, while that for Pb was about 5 × 10−4, which greatly exceeded the generally acceptable carcinogenic risk level of 10−4–10−6. It was concluded from the risk assessment that there is an immediate need for remediation of both carcinogens and non-carcinogens before construction of the reservoir. However, for a more accurate risk assessment, further specific estimations of the changes in environmental conditions due to the construction of the reservoir will be required; and more over, the effects of the pollutants to the ecosystem will also need to be evaluated.  相似文献   
252.

Background

Globally, every year several hundred million tons of problematic, e.g. chemical, wastes are generated stemming to more than 90% from the 25 OECD countries. Due to their partly considerable toxicity special and often expensive measures are required for their disposal. According to the Secretary of the ‘Basel Convention on the Control of Transboundary Movements of Hazardous Waste and Their Disposal’ annually at least 8.5 million tons of wastes are transboundarily traded. Although the ‘Basel Convention’ has set up rules how to handle international waste streams, certain waste amounts are illegally transported from the OECD countries to developing countries — basically for reasons of expenses. Often an environmental safe treatment of toxic waste is not ensured or even not possible in the receiving countries. As set forth in a report of the European Network for the Implementation and Enforcement of Environmental Law (IMPEL) published in 2006, the illegal trade with toxic waste has steadily increased. 3000 shipping documents of 17 European seaports were examined and 258 cargo holds were inspected showing that 68 of 140 waste shippings were illegal. Preventing illegal transports of waste meets with various obstacles. Controlling measures require considerable personal, technical, and logistic resources that are not sufficiently available in each country concerned. Missing or ineffective administrative structures hamper fast actions to stop illegal waste disposal. Partly, the political will to take the necessary steps is lacking. An additional problem is the fact that waste that is obtained from the regular shipping business is not subject to the Basel Convention but to the ‘International Convention for the Prevention of Pollution from Ships’. The implementing statures are summarized in the document MARPOL 73/78; the International Maritime Organization (IMO) is responsible. Identifying the origin of waste and thus defining the responsibility occasionally raises difficulties. This background provides a basis to try to reconstruct the course of events concerning the disposal of chemical waste in Abidjan.

Methods

Several information sources were utilized to reconstruct the course of events at Abidjan in August 2006; e.g. public press, declarations of international governmental organizations, especially of the UN and of its subsidiary organizations, communiqués of the Secretary of the Basel Convention, and statements of several NGOs. Nevertheless a complete reconstruction of the incident is impossible, since a detailed and reliable historical report is not available. Furthermore the responsible politicians have not undertaken significant efforts to shed light upon the incident. Additionally relevant documents of the participating companies are not available to the public.

Conclusions

The analyzed incident makes obvious that the control mechanisms of the Basel Convention can be circumvented. It remains unclear who has to take the political responsibility for the death of 10 people and for the health defects of thousands of humans. Possible civil and criminal consequences are not foreseeable for the actors and company owners involved in the illegal waste dumping. The people of Abidijan are confronted with unresolved questions regarding the occurrence of chronic diseases and possible long-term effects of remaining waste portions.

Recommendations and Perspectives

The incident demonstrates that the control of the transboundary transport and disposal of hazardous waste needs to be enforced and legal grey areas should be eliminated. It should be a task of the OECD countries and of all other economically and technically developed countries and organizations to support the developing countries’ efforts to build up the personal, technical, and infrastructural capacities for an efficient control of waste imports.  相似文献   
253.
Jung, Yong and Minha Choi, 2012. Survey‐Based Approach for Hydrological Vulnerability Indicators Due to Climate Change: Case Study of Small‐Scale Rivers. Journal of the American Water Resources Association (JAWRA) 48(2): 256‐265. DOI: 10.1111/j.1752‐1688.2011.00608.x Abstract: The vulnerability indicators can be used to develop water resource policy in the context of climate change. The Delphi method, an interactive prediction technique, is an efficient way to apply weighting functionality to vulnerability indicators consisting of three parts: Exposure, Sensitivity, and Adaptive Capacity on climate change. The Delphi method is an anonymous iterative survey of expert opinion, which is then shared with other participants. A total of three different rounds were carried out. The first round was a problem selection set, and the second and third were the standard Delphi survey. Fifty‐eight experts (66% academic and 34% practitioner) were invited. The rates of reply were 59, 50, and 38% for the first, second, and third Delphi processes, respectively. The degree of consensus of the Delphi survey was validated via variance changes and Kendall’s W test. Exposure and Adaptive Capacity presented increased levels of agreement among respondents in their given priorities. Particularly strong convergence (0.20 to 0.71 in Kendall’s W) of the experts’ opinions for Adaptive Capacity was observed. The results of this study indicate that finalized factors with ultimate weights through the Delphi method can be a strong support for governmental policy making with respect to climate change.  相似文献   
254.
Food and Environmental Virology - Retail foodservice establishments (FSE) frequently utilize washes with sanitizing agents during fresh produce preparation. This study evaluated the efficacy of...  相似文献   
255.
A monitoring method of biofouling in reverse osmosis (RO) system was proposed based on the fluorescent signal of resorufin, which is reduced by nicotinamide adenine dinucleotide released from viable cells during aerobic respiration. The fluorescent signal of resorufin reduced by planktonic cells and microorganisms of biofilm showed linearity, indicating its feasibility to monitor biofouling in a RO system. For the application of the method to the lab-scale RO system, the injection concentration of resazurin and the injection flow rate were optimized. Biofilm on RO membranes continuously operated in a lab-scale RO system was estimated by resorufin fluorescence under optimized detection condition. As a result, resorufin fluorescence on RO membrane showed a significant increase in which the permeability of RO system decreased by 30.48%. Moreover, it represented the development of biofilm as much as conventional biofilm parameters such as adenosine triphosphate, extracellular polymeric substances, and biofilm thickness. The proposed method could be used as a sensitive and low-cost technology to monitor biofouling without autopsy of membranes.  相似文献   
256.
Emission characterization of particle number as well as particle mass from three diesel passenger cars equipped with diesel particulate filter(DPF), diesel oxidation catalyst(DOC)and exhaust gas recirculation(EGR) under the vehicle driving cycles and regulatory cycle.Total particle number emissions(PNEs) decreased gradually during speed-up of vehicle from 17.3 to 97.3 km/hr. As the average vehicle speed increases, the size-segregated peak of particle number concentration shifts to smaller size ranges of particles. The correlation analysis with various particulate components such as particle number concentration(PNC),ultrafine particle number concentration(UFPNC) and particulate matter(PM) mass was conducted to compare gaseous compounds(CO, CO_2, HC and NOx). The UFPNC and PM were not only emitted highly in Seoul during severe traffic jam conditions, but also have good correlation with hydrocarbons and NOxinfluencing high potential on secondary aerosol generation. The effect of the dilution temperature on total PNC under the New European Driving Cycle(NEDC), was slightly higher than the dilution ratio. In addition, the nuclei mode(DP: ≤ 13 nm) was confirmed to be more sensitive to the dilution temperature rather than other particle size ranges. Comparison with particle composition between vehicle speed cycles and regulatory cycle showed that sulfate was slightly increased at regulatory cycle, while other components were relatively similar. During cold start test, semivolatile nucleation particles were increased due to effect of cold environment. Research on particle formation dependent on dilution conditions of diesel passenger cars under the NEDC is important to verify impact on vehicular traffic and secondary aerosol formation in Seoul.  相似文献   
257.
Variability in flower colour of animal-pollinated plants is common and caused, inter alia, by inter-individual differences in pigment concentrations. If and how pollinators, especially bees, respond to these small differences in pigment concentration is not known, but it is likely that flower colour variability impacts the choice behaviour of all flower visitors that exhibit innate and learned colour preferences. In behavioural experiments, we simulated varying pigment concentrations and studied its impact on the colour choices of bumblebees and honeybees. Individual bees were trained to artificial flowers having a specific concentration of a pigment, i.e. Acridine Orange or Aniline Blue, and then given the simultaneous choice between three test colours including the training colour, one colour of lower and one colour of higher pigment concentration. For each pigment, two set-ups were provided, covering the range of low to middle and the range of middle to high pigment concentrations. Despite the small bee-subjective perceptual contrasts between the tested stimuli and regardless of training towards medium concentrations, bees preferred neither the training stimuli nor the stimuli offering the highest pigment concentration but more often chose those stimuli offering the highest spectral purity and the highest chromatic contrast against the background. Overall, this study suggests that bees choose an intermediate pigment concentration due to its optimal conspicuousness. It is concluded that the spontaneous preferences of bees for flower colours of high spectral purity might exert selective pressure on the evolution of floral colours and of flower pigmentation.  相似文献   
258.
Together with other variables, human factors play a central role in the safety of highly complex technical systems such as nuclear power plants. However, despite the unquestionable importance of human factors, little information is available about relevant ability requirements for control room jobs in nuclear power plants. The purpose of this study was to close this gap, to provide specific information about ability requirements for such jobs, and to evaluate how several hypothesized factors (ability domain, type of job, and operating condition) contribute to ability requirements. We found that high levels of cognitive as well as social/interpersonal abilities are needed for control room jobs, and that ability requirements increase with the hierarchical job level for these two domains but decrease for psychomotor/physical abilities and for sensory/perceptual abilities. Furthermore, specifically concerning jobs with a leadership function, we found some differences between incidents and normal operations regarding requirements for social/interpersonal abilities, indicating that the former require a different leadership style than the latter.  相似文献   
259.
TACOM (TAsk COMplexity) is a measure for evaluating the complexity of tasks prescribed for emergency situations in nuclear power plants. Five sub-measures constituting TACOM represent five different aspects of the task complexity exhibited in operating procedures for emergency situations. The practicality of TACOM has been verified through a series of empirical studies. However, tasks designed for abnormal situations that can significantly affect the safety of nuclear power plants, also need a proper measure for evaluating their complexity. TACOM provides a process, a systematic cognitive task analysis method and a set of guidelines to support its application. Therefore, although the characteristics of abnormal task situations are not the same as those of emergency situations, TACOM seems to be reasonably applied to abnormal situations or at least to offer meaningful insights for developing a measure for evaluating the complexity of tasks in abnormal situations. Thus this study examined the applicability of TACOM to abnormal situations through case studies. Particular attention was paid to the sufficiency and appropriateness of the three methodological tools, which are the process, the cognitive task analysis method and the set of guidelines. Collective consideration of the case studies and the characteristics of tasks prescribed for abnormal situations led us to draw the conclusion that TACOM could be reliably used for abnormal situations as well. This paper reports the process of how to apply TACOM to the tasks of abnormal situations and discusses some lessons learned through this application.  相似文献   
260.
This study focused on the evaluation of leaching behaviours for arsenic and heavy metals (Cd, Cu, Ni, Pb and Zn) in soils and tailings contaminated by mining activities. Ten representative mine soils were taken at four representative metal mines in Korea. To evaluate the leaching characteristics of the samples, eight extraction methods were adapted namely 0.1?M HCl, 0.5?M HCl, 1.0?M HCl, 3.0?M HCl, Korean Standard Leaching Procedure for waste materials (KSLP), Synthetic Precipitation Leaching Procedure (SPLP), Toxicity Characteristic Leaching Procedure (TCLP) and aqua regia extraction (AR) methods. In order to compare element concentrations as extraction methods, relative extraction ratios (RERs, %), defined as element concentration extracted by the individual leaching method divided by that extracted by aqua regia based on USEPA method 3050B, were calculated. Although the RER values can vary upon sample types and elements, they increase with increasing ionic strength of each extracting solution. Thus, the RER for arsenic and heavy metals in the samples increased in the order of KSLP?相似文献   
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