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461.
The very significant impact of European legislation (Directive 91/414/EEC) on the authorization of plant protection products is reviewed herein, which has resulted in withdrawal of 704 active substances (AS) out of 889 assessed so far. The list of currently approved 276 AS includes 194 AS “existing” in the market before 1993 and 82 “new” AS introduced during the last 15 years. Results of toxicity characterization of the approved AS are also summarized, utilizing several well-known databases. Although significant data gaps exist for a rather large part of the approved AS, it is found that 84 AS are positive for at least one health effect (after chronic and/or acute exposure) including carcinogenicity, reproductive and neuro-developmental disorders, as well as endocrine disruption. The toxicity characterization results of this study are compared to those of recent assessments by other organizations (KemI, the Swedish Chemicals Agency, and the Pesticide Safety Directorate of the UK), where interpretation and use is made of AS “cut-off” criteria foreseen in new EU legislation. These studies report a comparatively smaller AS number with positive toxicity characterization. The possibility of some additional AS withdrawal in the near future, combined with the rather small rate of new AS introduction (approx. 5 per year) suggest that the list of approved AS over the next 10–15 years may not change very drastically. Consideration of the above trends is necessary and instructive in evaluating results of existing health impact assessment (HIA) studies, as well as in planning new ones. Due to the very drastic change in the number and type of marketed AS, that took place within the past 8–9 years, it is suggested that new HIA studies (based on epidemiological data after year 2000) should focus on a rather short time frame and, therefore, on appropriate cohort groups, e.g. young children. For the same reason, results of epidemiological studies of the past (involving banned AS) should be carefully interpreted and used with caution.  相似文献   
462.
结合模糊优选理论和灰色关联分析方法,提出灰色模糊综合评价法,该方法将灰色关联分析作为优属度确定的隶属度计算方法;提出理想环境序列建立遵循的原则,引入梯形模糊数实现定性指标量化并采用变异系数法确定评价指标权重.应用灰色模糊综合评价法对黄河流域河段水电规划的高坝方案和多级开发方案进行了比选研究,计算了两个方案的优属度及其开发性因子、稳定性因子、保护性因子、经济活力因子、社会可接受因子、环境风险因子等6个指标层优属度,结果表明,多级开发方案总体优于高坝方案;多级开发方案的保护性远好于高坝开发方案,而高坝方案的开发性略好于多级开发方案,稳定性、经济活力、社会可接受、环境风险等因子两种方案比较接近.评价结果与流域实际情况比较符合,证明该方法是一种有效的方法.  相似文献   
463.
This study has indicated that there is close relationship between development density and environmental quality; therefore, it is necessary to decide the form of development carefully beforehand. The form of development is shaped either by new development or urban renewal which is a major tactic nowadays adopted by the Hong Kong Government to improve the living condition of the citizens and the quality of the built environment. This study is limited to urban renewal and aims to find out the major urban design considerations for sustaining the environment. Through a questionnaire survey carried out in Hong Kong, the opinions of architects, planners, property development managers, and local citizens were sought and evaluated, and critical design factors for enhancing environmental sustainability of urban renewal projects are highlighted. The results derived from factor analysis indicated that certain design considerations should be incorporated for sustaining the urban environment. “Land Use Planning”, “Quality of Life”, “Conservation & Preservation”, “Integrated Design”, “Provision of Welfare Facilities”, and “Conservation of Existing Properties” were believed to be the significant underlying factors for achieving environmental sustainability of local urban renewal projects. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
464.
This paper focuses on comparative review and analysis of the systems of environmental protection, national environmental strategies and fundamentals of environmental legislation in Australia and the Russian Federation. These countries have many socioeconomic similarities, such as low population densities and richness in natural resources which are largely exported. The main disparity between Australia and Russia is in the types of economy. This paper ‘continues’ the sequence of recent scholarly publications on comparison of various features of environmental policies in the countries from all over the world. Comparative analysis in this research has been based on examination of scholarly publications, legislation, government documents, mass media sources and NGO responses. The analysis has revealed a number of differences including top-down implementation of policies in Russia whereas in Australia, each State (Territory) implements policies with significant independence from the Commonwealth Government. At the same time, similarities between the countries have been identified: for example, in deficits in the budget of local environmental authorities and in the presence of contradictions in legislation at national and regional levels of government. Suggestions resulting from this analysis include further integration of sustainable development strategies at all levels of Australian government to encourage further protection of the environment and, for Russia, creating a separate Ministry of Environmental Protection. These approaches should assist facilitation of sustainable development for both nations. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
465.
Like all rapidly developing countries, the government of Iran (GOI) has to integrate environment priorities into its energy sector. In order to integrate environmental concerns into energy sector, an Energy-Environment Review (EER) may be considered as the mainstreaming tool capable of examining the interface between energy and the environment. The results of the EER should be interpreted, in the light of the objective of the 4th Five Year Development Plan in Iran, to achieve fast and sustainable growth and accelerate the transition to a market economy. In particular, the suggested actions will promote economic efficiency use of energy resources through a proper allocation of scarce resources, including environmental resources, so as to achieve economic efficiency and environmental and social protection. This paper comprises: (A) an analysis of the current situation with regards to energy production and consumption; (B) an evaluation of the growth prospects with regard to energy production and consumption; (C) the identification of environmental issues induced by the generation and use of energy and estimation of the associated costs of damages; (D) the evaluation of the extent of contribution to the climate-change phenomenon through emission of greenhouse gases; (E) the evaluation of the proposed mitigation measures for the previously identified environmental problems; and (F) conclusions and recommendations. The EER-Iran assessed the total health damage from air pollution in 2001 at about 56  ×  1012 Rials (US $ seven billion); equivalent to 8.4% of nominal GDP. In the absence of the price reform and control policies, the EER-Iran estimated that the damage in Iran in the money of 2001, will grow to 155  ×  1012 Rials (US $ nine billion) by 2019. This is equivalent to 10.9% of nominal GDP, i.e., a large percentage of a larger GDP. Of this total, 107  ×  1012 Rials (US $ 8.4 billion) come from transport sector. The damage cost to the global environment from the flaring of natural gas, assessed on the basis of a carbon price of US $ 10/ton CO2, is found to be approximately US $ 600 million per year. Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.  相似文献   
466.
Using survey-based data approach for modeling the demand for environmental goods/resources, this study estimates income and price elasticities of demand for improved environmental quality of two National Parks in Northern Pakistan. The study uses data from two studies. The estimates indicate that improved environmental quality effects can be described as a luxury and an ordinary and price elastic service. Confidence intervals show however that the classification as a luxury is not statistically significant. Income elasticities of willingness to pay are estimated for a broad range of environmental services. The study finds that income and willingness to pay vary directly and significantly. The elasticity estimates, in general, are greater than zero, but less than unity. The study concludes that environmental improvements are more beneficial to low-income groups than for high-income groups.
Himayatullah KhanEmail:
  相似文献   
467.
The issue of the sustainable development of rural economies in England has recently received considerable attention. This is because many of the poorest areas in the country are rural, often of high environmental quality, but suffering from high unemployment and a lack of services and facilities. The rapid decline in agricultural incomes and in-migration of affluent urban workers since 1990 has exacerbated economic inequality in such areas. A number of factors have the potential to drive rural development and this paper applies, and considers, the feasibility of a method from the USA for combining economic and environmental variables in a regional growth model to examine the hypothesis that environmental quality is an important determinant of sustainable rural development in England. The model output suggests that, although environmental quality does play a role in sustainable rural development in England there are other, more important, factors driving development. These include business and communications infra-structure, the degree and opportunities for commuting and underlying employment prospects. The robustness and limitations of the method for combining economic and environmental variables is discussed in relation to the spatial interrelatedness of Local Authority Districts in England, and conclusions are drawn about areas for refinement and improvement of the method.
J. R. ParkEmail:
  相似文献   
468.
Cadmium (Cd) and Lead (Pb) are environmental pollutants. Environmental samples and bovine tissues were collected from the areas around a lead–zinc smelter in Guizhou, China for Cd, Pb, zinc (Zn) and copper (Cu) analysis. Cd in soil (10 mg/kg) and feed (6.6 mg/kg) from the polluted areas was 10 times higher than the Chinese Standards, resulting in higher Cd in bovine kidney (38 mg/kg) and liver (2.5 mg/kg). Pb in feed (132 mg/kg) from the polluted area was much higher than unpolluted areas, causing higher Pb levels in bovine tissues. Environmental Zn was elevated, but bovine tissue Zn was normal. Cu in bovine liver decreased with increased Cd and Pb. Metals in drinking water and in bovine muscle were within the Standard range. Thus, in the areas of this lead–zinc smelter, the environment has been contaminated with Cd and Pb, which has been transferred to cattle through the food chain.  相似文献   
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