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161.
Risk management of chemicals requires information about their adverse effects such as toxicity and persistence, for example. Testing of chemicals allows for improving the information base for regulatory decision‐making on chemicals' production and use. Testing a large number of chemicals with limited time and resources forces a prioritization of chemicals. This paper proposes a decision model that provides a ranking of chemicals according to “urgency to test”. The model adopts a value‐of‐information approach describing the expected welfare gains from regulatory actions that respond to test information. We determine the value‐of‐information of tests revealing chemicals' levels of toxicity and persistence. We compare our findings to the prioritization of chemicals in the new European Chemicals Regulation “REACH”, where several tens of thousands of chemicals are to be tested in order to fill existing information gaps and to implement more effective risk management. We find that the main lines of chemicals' prioritization under REACH receive backing from our decision model. However, prioritization for testing can be further improved by accounting for testing costs and the sensitivity of regulatory action with respect to the test information.  相似文献   
162.
In 2006, a controlled infection study was performed in the ‘Kranzberger Forst’ to address the following questions: (1) Will massive artificial inoculation with Apiognomonia errabunda override the previously observed inhibitory effect of chronic ozone? (2) Can biochemical or molecular markers be detected to account for the action of ozone? To this end six adult beech trees were chosen, three ozone fumigated (2× ozone) and three control trees (ambient = 1× ozone). Spore-sprayed branches of sun and shade crown positions of each of the trees, and uninoculated control branches, were enclosed in 100-L plastic bags for one night to facilitate infection initiation. Samples were taken within a five-week period after inoculation. A. errabunda infestation levels quantified by real-time PCR increased in leaves that were not fumigated with additional ozone. Cell wall components and ACC (ethylene precursor 1-amino cyclopropane-1-carboxylic acid) increased upon ozone fumigation and may in part lead to the repression of fungal infection.  相似文献   
163.
Eels are an ideal biomonitor for persistent organic pollutants (POPs) because of their high lipid content, longevity and tendency to remain within a defined range during their freshwater life phase. This study investigated concentrations of POPs in eels (Anguilla anguilla) from 30 sites across Scotland, including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (BDEs), DDT (and metabolites), hexachlorocyclohexanes (α, β, γ-HCH), hexachlorobenzene (HCB), hexachlorobutadiene (HCBD) and pentachlorobenzene. Despite its EU-wide ban ∼30 years ago, DDT and its derivatives were detected in almost all samples. PCB 153 and 138 were the most widely detected PCB congeners, while BDE 47 was the dominant BDE. Pentachlorobenzene was not detected, while HCBD was detected once only. α-HCH, β-HCH and HCB concentrations were very low (generally <3 μg/kg or below detection). When compared with 1986 and 1995 data, the results revealed considerable decreases in p,p′-DDE concentrations. More drastic reductions were evident for γ-HCH, reflecting the tightening restrictions on pesticide use imposed over the previous decades.  相似文献   
164.
Linke S  Dreyer M  Sellke P 《Ambio》2011,40(2):133-143
The protection of the Baltic Sea ecosystem is exacerbated by the social, environmental and economic complexities of governing European fisheries. Increased stakeholder participation and knowledge integration are suggested to improve the EU’s Common Fisheries Policy (CFP), suffering from legitimacy, credibility and compliance problems. As a result, the CFP was revised in 2002 to involve fisheries representatives, NGOs and other stakeholders through so called Regional Advisory Councils (RACs) in the policy process. We address the RAC’s task to incorporate stakeholder knowledge into the EU’s fisheries governance system in empirical and theoretical perspectives. Drawing on a four-stage governance concept we subsequently suggest that a basic problem is a mismatch between participation purpose (knowledge inclusion) and the governance stage at which RACs are formally positioned (evaluation of management proposals). We conclude that, if the aim is to broaden the knowledge base of fisheries management, stakeholders need to be included earlier in the governance process.  相似文献   
165.
松花江哈尔滨段流域是哈尔滨市重要的水源地,也是松花江重要的组成部分,其生态环境问题一直受到国内外学者密切关注,且近年来松花江哈尔滨段水体改善程度较为明显,流域内水体变化程度越来越受到相关学者和民众的重视,研究松花江哈尔滨段水体变化趋势意义明显。该研究的创新性在于运用典范对应分析(CCA)探究藻类植物与环境因子变化的关系,并运用欧洲硅藻数据库(EDDI)验证主要环境因子的准确性。国内现行的一些常规理化指标单独评价水体质量较为单一,不能更好地满足现行的水环境管理要求,并且对于水环境的变化反应效果及准确度较低。该研究运用相关理化指标数据和藻类植物的种类及丰度等的年际变化,实现从单一理化指标评价改善为理化和生物指标双重评价,从而更加具体地反映出松花江哈尔滨段水体状况的变化趋势。  相似文献   
166.
The European eel’s swimbladder nematode, Anguillicola crassus, sampled from the Asi River (Orontes River) in Antakya (Hatay, Turkey) in May 2006 were analysed by Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) for their some heavy metal (Cd, Cr, Cu, Fe, Hg, Mn, Pb and Zn) levels. The metal concentrations of the parasites were compared to different organs (swimbladder, liver, muscle and skin) of the fish hosts. The parasite contained statistically highly significantly amounts of Fe (P < 0.05). The iron level of nematode was up to 25.52 times than the muscle of its host, Anguilla anguilla. However, bioconcentration of Cd, Cr, Cu, Hg, Mn, Pb, Zn were detected in the A. crassus and it contained no statistically differences with the other tissues of its host, the eel (P > 0.05). Furthermore, no significant differences were detected in the heavy metal accumulations between the parasitized and un-parasitized fish tissues. The analysed metals (Cd, Cr, Cu, Fe, Mn, Pb and Zn) were found in fish muscle at mean concentrations under the permissible limits proposed by FAO.  相似文献   
167.
Dibutyl phthalate, a known endocrine disruptor, is a commonly used plasticizer that influences the glucose homeostasis. The present study elucidates the effects of dibutyl phthalate (1 and 5 mmol/L) on electrogenic sodium-linked glucose transport in the isolated rabbit ileum with ‘Ussing chamber.’ Serosal addition of dibutyl phthalate has no effect on glucose-based electrogenic changes in short circuit current, and no effect of dibutyl phthalate is observed on ileal tissue conductance and catalase activity. However, mucosal addition of dibutyl phthalate in the presence of glucose shows a trend of decrease in short circuit current compared with the control. This indicates that dibutyl phthalate may have a deleterious effect on the electrogenic intestinal glucose transport.  相似文献   
168.
We exposed female European starlings to a pentabromodiphenyl ether (Penta-BDE) mixture through subcutaneous implants, and examined levels and profiles of polybrominated diphenyl ethers (PBDEs) together with reproductive effects. Sum PBDE levels increased significantly in the serum of the exposed females from 218 ± 43 to 23,400 ± 2035 pg/ml. Sum PBDE concentrations in the eggs of the exposed group ranged from 130 ± 12 to 220 ± 37 ng/g wet weight (ww). The profile in serum after egg laying was very similar to that in eggs. There were no detectable levels of HO-PBDEs in both serum and eggs. Fewer females of the exposed group initiated egg laying compared to the control group, although the difference was not significant. In addition, egg weight and volume were significantly higher in the exposed group. These results suggest that, at the investigated exposure levels (150 μg sum PBDEs/bird), PBDEs may have a negative effect on reproductive performance.  相似文献   
169.
气候变化问题已被公认为是全球范围内可持续发展面临的最大威胁,碳泄漏问题是目前气候变化领域的一个热点问题.欧盟等以存在碳泄漏为由欲对非减排国家征收碳关税.在此背景下,本文对碳泄漏问题进行理论分析和实证研究.理论分析认为,碳泄漏有三个主要渠道:化石能源的国际贸易、碳密集型产品的国际贸易和能源密集型产业的国际转移,其中,碳密集型产品的国际贸易一直是争论的核心.在此基础上,本文从碳密集型产品的国际贸易角度对中国与欧盟之间碳泄漏问题进行了实证研究.本文选取钢铁、有色金属、水泥、化肥、玻璃和玻璃制品、纸张和纸制品六个碳密集型产业为研究对象,以中国与欧盟碳密集型产品的进出口比率作为指标,考察欧盟实施温室气体减排措施(1992年)以来该指标的变化趋势,以确定中国与欧盟之间是否发生了碳泄漏以及程度如何.研究结果表明,中国与欧盟之间可能并未发生碳泄漏,或者即使发生了碳泄漏,其程度也很微弱,不足以成为欧盟征收碳关税的理由.  相似文献   
170.
Measurements of ground-level ozone concentrations and meteorology (temperature, vapour pressure deficit (VPD), solar radiation) at the monitoring site Ostad (south-west Sweden) were compared to data from the corresponding grid in the EMEP photo-oxidant model for 1997, 1999 and 2000. The influence of synoptic weather on the agreement between model and measurements was studied. Implications of differences between modelled and observed inputs for ozone flux calculations for wheat and potato were investigated. The EMEP model output of ozone, temperature and VPD correlated well with measurements during daytime. Deviations were larger during the night, especially in calm conditions, attributed to local climatological conditions at the monitoring site deviating from average conditions of the grid. These differences did not lead to significant differences in calculated ozone uptake, which was reproduced remarkably well. The uptake calculations were sensitive to errors in the ozone and temperature input data, especially when including a flux threshold.  相似文献   
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