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[en] The general concept for risk assessment in accordance with the Swedish model for contaminated soil implies that the toxicological reference value for a given receptor is first back-calculated to a corresponding concentration of a compound in soil and (if applicable) then modified with respect to e.g. background levels, acute toxicity, and factor of safety. This result in a guideline value that is subsequently compared to the observed concentration levels. Many sources of uncertainty exist when assessing whether the risk for a receptor is significant or not. In this study, the uncertainty aspects have been addressed from three standpoints: 1. Uncertainty in the comparison between the level of contamination (source) and a given risk criterion (e.g. a guideline value) and possible implications on subsequent decisions. This type of uncertainty is considered to be most important in situations where a contaminant is expected to be spatially heterogeneous without any tendency to form isolated clusters (hotspots) that can be easily delineated, i.e. where mean values are appropriate to compare to the risk criterion. 2. Uncertainty in spatial distribution of a contaminant. Spatial uncertainty should be accounted for when hotspots are to be delineated and the volume of soil contaminated with levels above a stated decision criterion has to be assessed (quantified). 3. Uncertainty in an ecological exposure model with regard to the moving pattern of a receptor in relation to spatial distribution of contaminant in question. The study points out that the choice of methodology to characterize the relation between contaminant concentration and a pre-defined risk criterion is governed by a conceptual perception of the contaminant's spatial distribution and also depends on the structure of collected data (observations). How uncertainty in transition from contaminant concentration into risk criterion can be quantified was demonstrated by applying hypothesis tests and the concept of confidence interval under different assumptions regarding the data structure. The results stress the importance to invoke statistical methods and also illustrate how the choice of a wrong methodology may affect the quality of risk assessment and foundations for decision making. The uncertainty in assessing the volume of contaminated soil was shown to be dependant only to a low extent on the interpolation technique used for the specific case study analyzed. It is, however, expected that the uncertainty may increase significantly, if more restrictive risk criteria (lower guideline value) are applied. Despite a possible low uncertainty in assessing the contaminated soil volume, the uncertainty in its localization can be substantial. Based on the demo example presented, it comes out that the risk-based input for decision on soil treatment may vary depending on what assumptions were adopted during interpolation process. Uncertainty in an ecological exposure model with regard to the moving pattern of a receptor in relation till spatial distribution of contaminant has been demonstrated by studies on pronghorn (Antilocapra americana). The results from numerical simulations show that a lack in knowledge on the receptor moving routes may bring about substantial uncertainty in exposure assessment. The presented concept is mainly applicable for 'mobile' receptors on relatively large areas. A number of statistical definitions/methods/concepts are presented in the report of which some are not elaborated on in detail, while readers are referred to proper literature. The mail goal with the study has been rather to shed more light on aspects related to uncertainty in risk assessment and to demonstrate potential consequences of wrong approach than to provide readers with formal guideline and recommendations. However, the outcome from the study will hopefully contribute to the further work on novel approaches towards more reliable risk assessments
[en] Despite considerable progress in ecotoxicology, it has become clear that this discipline cannot answer its central questions, such as, “What are the effects of toxicants on biodiversity?” and “How the ecosystem functions and services are affected by the toxicants?”. We argue that if such questions are to be answered, a paradigm shift is needed. The current bottom-up approach of ecotoxicology that implies the use of small-scale experiments to predict effects on the entire ecosystems and landscapes should be merged with a top-down macroecological approach that is directly focused on ecological effects at large spatial scales and consider ecological systems as integral entities. Analysis of the existing methods in ecotoxicology, ecology, and environmental chemistry shows that such integration is currently possible. Therefore, we conclude that to tackle the current pressing challenges, ecotoxicology has to progress using both the bottom-up and top-down approaches, similar to digging a tunnel from both ends at once. - To tackle the current pressing challenges, ecotoxicology has to progress using both the bottom-up experimental and top-down observational approaches.
[en] Nanotechnology is a representative emerging technology in an embryonic stage. Due to the continuous support provided by both the public and private sectors of many countries, nanotechnologies have increasingly been commercialized in a wide array of industries, but also produce many commercialization failures. Tackling this problem, we investigate key factors affecting the commercialization of nanotechnologies. Identifying key factors of nanotechnology commercialization through literature review and interview with CEOs, we collected data of 206 Korean nanotechnology-based companies, and analyzed the causal relationship between key factors and financial performance. Logistic and Tobit regression models are used. Overall, companies achieving successful commercialization hold some common characteristics including consistent exploratory R and D, governmental funding, and nano-instrument/energy/environment-related products. Also, the use of potentially toxic materials makes commercialization difficult even if the products are not toxic.
[en] Dielectric elastomer based generators (DEGs) offer some unique properties over energy generators based on other materials. These properties include high energy density, high efficiency over a broad range of frequencies, low compliance, the ability to produce high strain, large area, low cost films with no toxic materials and wide range environmental tolerance. As further shown in this paper, DEG materials can also exhibit a non-linear dynamic behavior, enhancing broad-band energy transfer. More specifically, dielectric elastomer (DE) energy generating synergetic structures (DIESYS) are considered as dynamic energy absorbers. Two elementary characteristic DIESYS design concepts are examined, leading to a typical antagonistic configuration for in-plane oscillations and a typical synagonistic configuration for out-of-plane oscillations. Originally, all the DE elements of the structure are assumed to be always in tension during all the phases of the harvesting cycle, conforming to the traditional concept of operation of DE structures. As shown in this paper, the traditional always-in-tension concept results in a linear dynamic system response, despite the fact that the implemented (DE) parts are considered to have been made of a non-linear (hyperelastic) material. In contrast, the proposed loose-part concept ensures the appearance of a non-linear broad-band system response, enhancing energy transfer from the environmental source. (paper)
[en] The Threat and Consequence Assessment Division (TCAD) of the U.S. Environmental Protection Agency's (EPA) National Homeland Security Research Center (NHSRC) is developing methodology for performing rapid risk assessments needed for incident management, cleanup, and mitigation of hazards in the aftermath of a terrorist event. TCAD, working with the Department of Defense's Chemical and Biological Defense Information Analysis Center (CBIAC, operated by Battelle) has developed SERRA - Support for Environmental Rapid Risk Assessment. This paper describes the methodology utilized to formulate SERRA, presents current contents of the SERRA database (information derived from assessments of over 3,000 publications selected from 10,000 citations), and describes SERRA implementation. The paper also discusses how an Internet-accessible version of the SERRA database could be utilized by a country or countries to prepare for and respond to the intentional release of chemical, biological or radiological materials.(author)
[en] Industrial facilities, which use toxic chemicals in their production processes, are tempting targets for military and terrorist strategists. They know that these facilities when attacked could produce effects not realizable with conventional weapons. The resulting legal, policy and political consequences would be minimal as compared to that of disseminating toxic chemicals or chemical agents as weapons on enemy territory. At this time there is no clear definition of the legality or illegality of these types of actions used against specific industrial targets for the purpose of mass destruction or disruption. Without clearly defined international regulations covering these actions, we must depend solely on national defense systems. Not only are these regulation not defined, there are no implementation tools, which would be available if the various treaties (CWC/BWC) etc., were able to incorporate needed legislative action. Consequently we must depend on and put into practice defense security standards for industrial facilities for protection against both possible terrorist and military attacks. Emergency responses to incidents involving violent criminals and terrorists are extremely dangerous. Incidents involving weapons of mass destruction, firearms, and hazardous materials have resulted in the injury and death of many firefighters, police officers and medical personnel. We wish to intend display place and role of intelligence and counter intelligence system to prevention potential target and military attack. Security needs to be incorporated into the public safety culture and it must become the routine for how we operate. The recognition and identification process is an important skill that needs continual refinement. The use of transportation or facility paperwork assists in recognizing what potential hazards. A key factor in the successful command and management of a hazmat incident or terrorism event is the ability of public safety agencies to function as a team. A terrorism event or hazmat crime brings multiple agencies together, but their integration needs to be seamless. Response to these incidents presents acute and long term health risks to public safety personnel. There are many factors involved in the selection and use of protective equipment. New threats and technology are emerging. Then we will describe the specific situation by participating in joint-agency working groups and by maintaining regular liaison and routine coordination with local and state law enforcement and intelligence agencies. Applicable regulations and national consensus standards governing emergency response and post-emergency response operations conducted at criminal or terrorist incidents involving hazardous materials or attack on oil, chemical and petrochemical industry.(author)
[en] Full text: Government of the Republic of Tajikistan has signed Convention "On prohibition of chemical weapon application"and no chemical weapon (CHW) is produced on the territory of republic. However, the potential production of CHW by individual persons or groups can be organized, using available production and obtaining chemical substances from other countries. Chemical substances, which have strong damage effect, easily, can be synthesized in chemical laboratories. These are general toxic substances, as hydrocyanic acid acid, phosgene, mustard gas, lewisite, sarin and others. The similar chemical substances of industrial significance are produced in Tajikistan: ammonia, chlorine, explosives, caustic soda, carbamide, formaldehyde and others. For industrial needs and agriculture from other countries Tajikistan is receiving the following: sodium cyanide and potassium for gold-mining; mineral acids; pesticides and others. Besides, there are different deposits in Tajikistan, reprocessing of which gives an opportunity to obtain different chemical substances. What can be obtained from chemicals produced in Tajikistan? Chlorine - from this reagent the fluoride chlorine, phosgene COCl_2 and many other compounds are easily synthesized, which are CHW components. Obtained cyanic compounds for gold mining can be used as precursor for neuroparalytic action. A big amount of metallic aluminum is produced in the republic. The Al powder for rocket fuel can be obtained from it. Obtained from other countries pesticides are potential components for CHW creation. A strong control and account of pesticides use is necessary. It is extremely important to control materials, equipment and technologies which allow countries and separate groups to create weapons of mass destruction (WMD). The most important factor is goods identification. Firstly - inspection of external view, labeling, packing specifications, license availability and etc. Strong control of checklists is necessary according to precursor which can create CHW. Many chemical substances, containing phosphor, sulfur, fluorine, chlorine can be precursor for CHW. Important precursors imported to republic can be: thioglycol, phosphorus trichloride, trimethyl phosphate, K F, HF, dimethylamine, diethyl phosphate, arsenic chloride, KCN, NH_4F, triethanolamine, Na_2S, sulfur dichloride, phosphor pentasulfide and etc. Manufacturing capacity and equipment are also elements of CHW creation. These equipment of dual use, such as reaction vessel, heat exchanger, distillation columns, pumps, furnaces and etc. Thus, for WMD non-proliferation a strong export and import control of chemical substances is necessary.
[en] The invention concerns a barrel which has a lid seal and is used for the inward and outward transfer of radioactive or toxic substances in a contamination-free manner. The barrel comprises a flanged edge and a deformable annular seal disposed between the inner lid of the double-lid system and the barrel. The inner lid comprises a pivotable lever with a rounded end as an element for locking with the barrel, the lever acting on the inner wall of the barrel, below the seal which engages at least partially around the flanged edge in a form-locking manner. Placed on the smooth region of the barrel wall on which the lever acts, below the seal, is a support ring having a recess which is directed towards the barrel interior and in which the rounded end of the pivotable lever engages when the barrel is locked. (author) figs