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1.
广东省生态安全状态及趋势定量评价   总被引:27,自引:3,他引:27  
为研究区域生态安全在不同时期的动态变化及发展趋势,在国内外已有的研究基础上,根据压力-状态-响应模型框架,提出了一套完整的区域生态安全水平度量的指标体系和基于熵权法赋权的综合指数评价方法,从时间尺度上(1990~2004年)对广东省生态安全进行定量评估和动态趋势分析.结果表明,广东省生态安全综合指数从1990年的0.125增加至2004年的0.402,生态安全整体水平呈逐年上升趋势,但发展过程中存在的问题是区域生态压力在不断加大及生态安全现状水平仍处于“较不安全”状态.对广东省环境规划的实施效果进行预测评估,得出在实现环境目标的情景下,2010规划年和2020规划年的生态安全综合指数将分别达到0.533(临界安全)和0.691(较安全).评价方法简单直观,评价结果客观合理.  相似文献   

2.
The process of quantitatively predicting the likelihood of an adverse response in humans or wildlife due to exposure to one or more chemicals is collectively known as environmental risk assessment. Quantitative risk assessment has been practiced in the United States and Canada for nearly 20 years and is the basis for most environmental and many occupational health regulations in North America. However, only since 1990 has it begun to receive serious consideration in Europe, Australia, Asia, and other regions. This paper reviews the historical evolution of health risk assessment in the United States and the scientific shortcomings in the process that have been introduced due to various regulatory policies. Despite these limitations and the reluctance of some countries to implement risk‐based policies, risk assessment will undoubtedly grow in importance within the international arena as other countries search for an ideal balance between cost and risk reduction. With the emergence of risk analysis as an international tool for understanding environmental issues, several improvements to the risk assessment process are recommended here that the United States and other countries could immediately incorporate into hazard identification, dose‐response and exposure assessments, and risk characterization. Examples of these improvements include use of a weight‐of‐evidence approach, physiologically‐based pharmacokinetic (PB‐PK) modelling, Monte Carlo techniques, and uncertainty analyses. These recommendations could, if coupled with an understanding of the historical experience in the United States, lead to superior environmental risk assessment policies for all countries as they enter the 21st century.  相似文献   

3.
This study was chosen as an example of integrated risk assessment because organophosphorous esters (OPs) share exposure characteristics for different species, including human beings and because a common mechanism of action can be identified. The “Framework for the integration of health and ecological risk assessment” is being tested against a deterministic integrated environmental health risk assessment for OPs used in a typical farming community. It is argued that the integrated approach helps both the risk manager and the risk assessor in formulating a more holistic approach toward the risk of the use of OP-esters. It avoids conclusions based on incomplete assessments or on separate assessments. The database available can be expanded and results can be expressed in a more coherent manner. In the integrated exposure assessment of OPs, the risk assessments for human beings and the environment share many communalities with regards to sources and emissions, distribution routes and exposure scenarios. The site of action of OPs, acetylcholinesterase, has been established in a vast array of species, including humans. It follows that in the integrated approach the effects assessment for various species will show communalities in reported effects and standard setting approaches. In the risk characterization, a common set of evidence, common criteria, and common interpretations of those criteria are used to determine the cause of human and ecological effects that co-occur or are apparently associated with exposure to OPs. Results of health and ecological risk assessments are presented in a common format that facilitates comparison of results. It avoids acceptable risk conclusions with regard to the environment, which are unacceptable with regard to human risk and vice versa. Risk managers will be prompted to a more balanced judgement and understanding and acceptance of risk reduction measures will be facilitated.  相似文献   

4.
The World Health Organization's International Programme on Chemical Safety (IPCS), the Organization for Economic Cooperation and Development (OECD), and the U.S. Environmental Protection Agency have developed a collaborative partnership to foster integration of assessment approaches for human health and ecological risks. This paper presents the framework developed by that group. Integration provides coherent expressions of assessment results, incorporates the interdependence of humans and the environment, uses sentinel organisms, and improves the efficiency and quality of assessments relative to independent human health and ecological risk assessments. The paper describes how integration can occur within each component of risk assessment, and communicates the benefits of integration at each point. The goal of this effort is to promote the use of this internationally accepted guidance as a basis for harmonization of risk assessment.  相似文献   

5.
After 20 years of development, ecological risk assessment is widely accepted. However, it is evolving in response to a variety of technical and societal pressures. First, pressure for greater simplicity and standardization arise from the expectation that risk assessments should require little time and resources but be defensible. Second, the advance of the environmental sciences and increasing awareness of the complexity of ecological responses generate pressure for greater realism. Third, the dominance of human health risk assessment generates a pressure to integrate ecological risk assessment with that dominant field. Fourth, the demand for cost-benefit analysis creates pressure for integration with environmental economics. Finally, the need to connect the practice of ecological epidemiology with risk-based decision-making creates a pressure of the formation of a single integrated ecological assessment practice.  相似文献   

6.
This paper synthesizes several presentations on the use of indicators in ecological risk assessments for persistent, bioaccumulative toxicants (PBTs). The presentations were organized around two chemical case studies: (1) mercury, and (2) compounds that exhibit an Ah-receptor based mode-of-action. Presenters summarized the current practice of ecological risk assessment for these compounds and described research on known or suspected impacts. In addition, this paper addresses three special topics that apply broadly to all PBTs: (1) the convergence of ecological assessment and ecological risk assessment, (2) integration of ecological and human health risk assessment, and (3) risk assessments for population-level effects.  相似文献   

7.
Conceptual models are representations of the assumed relationship between sources and effects. They serve three important purposes. (1) Their creation compels assessors to think through and clarify their assumptions concerning the activities being assessed. (2) They serve as a communication tool for conveying those assumptions to risk managers and stakeholders. (3) They provide a basis for organizing and conducting the risk assessment. Conceptual models for risk assessments of chemical contaminants have not been problematical because they simply portray the flow of the contaminant from a source to a receptor that experiences toxic effects. However, ecological risk assessments must increasingly deal with direct and indirect effects on multiple endpoint receptors and with multiple complex activities including both physical effects and toxic effects. This complexity may result in conceptual models that are incomplete, ambiguous, or simply too complex to be understood. This paper presents a strategy for creating conceptual models for complex ecological risk assessments that are not only complete but also clear and comprehensible. The strategy also promotes efficiency by creating modular component models for activities, sites, and receptors that can be reused in different combinations in different assessments.  相似文献   

8.
Successful ecological risk assessments are all alike; every unsuccessful ecological risk assessment fails in its own way. Tolstoy posited a similar analogy in his novel Anna Karenina: “Happy families are all alike; every unhappy family is unhappy in its own way.” By that, Tolstoy meant that for a marriage to be happy, it had to succeed in several key aspects. Failure on even one of these aspects, and the marriage is doomed. In this paper, I argue that the Anna Karenina principle also applies to ecological risk assessments involving multiple stressors. In particular, I argue that multiple stressors assessments and environmental decision making will not have a happy marriage unless the following can be achieved: (1) there must be societal and political buy-in to the assessment and decision-making process; (2) the assessment must have the latitude to consider a wide range of stressors and potential risk management options; (3) there must be a commitment to following a rigorous focusing of the assessment and to expending resources for model development and data collection; and (4) an adaptive management strategy must be adopted wherein risk management actions are undertaken, system response intensively observed and assessed, and revised management actions taken as appropriate. Failure to meet any of the above criteria for success will doom a multiple stressors assessment and prevent its use in effective decision-making.  相似文献   

9.

Foundational activities at the international level underlie current risk and safety assessment approaches for genetically engineered/modified organisms (GEOs/GMOs). Early risk assessment considerations beginning with the OECD ‘Blue Book’ established risk/safety assessment as the characterization of the organism and its environmental release; establishment and persistence in the environment; and human and ecological effects, analyzed in principle through existing methods. Important in this context was recognition that GEOs/GMOs as a class did not represent new risks relative to products of traditional plant breeding and that any incremental risk would need to be established on a stepwise case-by-case comparative basis with existing crops and derived-foods as the baseline. Accordingly, concepts of familiarity and substantial equivalence were advanced by OECD and WHO as ways to establish a risk analysis baseline for determining whether and to what extent risk/safety assessment was needed. Regulatory implementations of this paradigm have skewed to increasingly complex portfolios of studies rather than adhering to analysis which is formulated to fit the risk/safety questions relevant to a given case. Plants produced through genome editing technology will benefit from risk analysis that implements sound problem formulation to guide the need for and nature of risk/safety assessments.

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10.
生态风险评价方法述评   总被引:21,自引:6,他引:21  
张思锋  刘晗梦 《生态学报》2010,30(10):2735-2744
生态风险是由环境的自然变化或人类活动引起的生态系统组成、结构的改变而导致系统功能损失的可能性。生态风险评价是定量预测各种风险源对生态系统产生风险的或然性以及评估该风险可接受程度的方法体系,因而是生态环境风险管理与决策的定量依据。在介绍了生态风险概念的基础上,按照风险源性质的分类标准将生态风险划分为化学污染类风险源、生态事件类风险源、复合类风险源3类,并分别论述了3类生态风险对应评价方法的特点与发展的方向。另外,针对生态风险评价研究的现状,讨论了我国生态风险研究的优先领域,包括建立急性、慢性毒理数据库,构建外来生物入侵风险评价标准等,同时,建议将综合概率统计学、复杂系统理论与遥感技术等手段引入生态风险评价方法中,以进一步提高风险评价结果在生态风险管理中的有效性。  相似文献   

11.
This paper aims to highlight the considerable potential of a better integration of ecological theory in aquatic ecotoxicology. It outlines how community ecology, studies on trophic interaction and disturbance ecology could provide an enhanced theoretical basis for aquatic ecotoxicology and increase ecological relevance in environmental risk assessment of chemicals. Based on the literature and own research, approaches from aquatic ecotoxicology are presented, which are based on ecological considerations and address a higher level of biological complexity for risk assessment strategies of chemicals. The concepts of species-sensitivity distribution (SSD), pollution-induced community tolerance (PICT), the use of model ecosystems and the sediment quality triad (SQT) in ecological risk assesment as well as inputs from ecotoxicology into landscape ecology are illustrated. These examples aim to evidence aquatic ecotoxicology as a rewarding field of ecological research.  相似文献   

12.
Advances in gene editing have made feasible the potential use of gene drive for pest control. Ecological risk assessments will certainly be required before this technology can be released into open fields. In this article, I argue for the importance to include host-associated differentiation (HAD) as part of ecological risk assessment models due to its potential to modulate gene drive spread and risk. Depending on the context, HAD may hamper or facilitate pest control efforts using gene drives. Overlooking HAD may impair pest suppression goals and inflate estimations of effective population sizes, whereas its inclusion within gene drive deployment strategies, as a form of ecological containment, may facilitate gene drive implementation under specific scenarios. Because HAD varies geographically and among closely related species, it will need to be assessed on a case-by-case basis. Failure to incorporate HAD within ecological risk assessment models may undermine pest control goals and diminish the accuracy of estimated ecological risks associated with gene drive releases.  相似文献   

13.
An international database for pesticide risk assessments and management   总被引:2,自引:0,他引:2  
Despite a changing world in terms of data sharing, availability, and transparency, there are still major resource issues associated with collating datasets that will satisfy the requirements of comprehensive pesticide risk assessments, especially those undertaken at a regional or national scale. In 1996, a long-term project was initiated to begin collating and formatting pesticide data to eventually create a free-to-all repository of data that would provide a comprehensive transparent, harmonized, and managed extensive dataset for all types of pesticide risk assessments. Over the last 20 years, this database has been keeping pace with improving risk assessments, their associated data requirements, and the needs and expectations of database end users. In 2007, the Pesticide Properties DataBase (PPDB) was launched as a free-to-access website. Currently, the PPDB holds data for almost 2300 pesticide active substances and over 700 metabolites. For each substance around 300 parameters are stored, covering human health, environmental quality, and biodiversity risk assessments. With the approach of the twentieth anniversary of the database, this article seeks to elucidate the current data model, data sources, its validation, and quality control processes and describes a number of existing risk assessment applications that depend upon it.  相似文献   

14.
15.
Scope and Background  This paper presents the preliminary results from an ongoing feasibility study, investigating potential application of elements from the life cycle assessment (LCA) framework in European chemicals’ policy. Many policy areas affect manufacturing, marketing and use of chemicals. This article focuses on the general chemical legislation, especially issues related to regulatory risk assessment and subsequent decisions on risk reduction measures. Method  Current and upcoming chemical regulation has been reviewed and empirical knowledge has been gained from an ongoing case study and from dialogues with various stakeholders. Results and Discussion  LCAs are comparative and more holistic in view as compared to chemical risk assessments for regulatory purposes1. LCAs may therefore potentially improve the basis for decisions between alternatives in cases where a risk assessment calls for risk reduction. In this process, LCA results might feed into a socio-economic analysis having similar objectives, but some methodological aspects related to system boundaries need to be sorted out. Life cycle impact assessment (LCIA) of toxic effects has traditionally been inspired by the more regulatory-orientated risk assessment approaches. However, the increasing need for regulatory priority setting and comparative/ cumulative assessments might in the future convey LCIA principles into the regulatory framework. The same underlying databases on inherent properties of chemicals are already applied in both types of assessment. Similarly, data on the use and exposure of chemicals are needed within both risk assessments and LCA, and the methodologies might therefore benefit from a joint ‘inventory’ database. Outlook  The final outcome of the feasibility study will be an implementation plan suggesting incorporation of core findings in future chemical regulation and related policy areas.  相似文献   

16.
The Precautionary Principle, generated during the late 1980s as a unifying principle for regulating discharge of hazardous material into the North Sea, has been broadened to include a shifting of the burden of proof to the proponent of a proposed activity, adoption of a more holistic assessment process, and encompassing all environmental management decisions, not just pollution prevention activities. We argue that the Precautionary Principle remains a management philosophy, not a substitute for risk assessment. Risk assessment is a tool for organizing information used in environmental management decisions. However, increasing attention to reducing the Type II error of risk assessment studies would significantly reduce the skepticism with which many view the risk assessment process. A critical review of default assumptions used in risk assessments, inclusion of indirect effects within an ecologically relevant spatial/temporal framework, and better communication between risk assessors and risk managers also would enhance the acceptability of the process. Risk assessment can provide a sound basis for management decisions regardless of the underlying philosophies of environmental conservation or utilitarianism, but only if the inherent biases in the risk assessment assumptions are acknowledged explicitly throughout the assessment and management processes.  相似文献   

17.
The need for the integration of the assessment of human and ecological risks in contaminated areas, such as derelict mines, widely increases. The risk assessment process is becoming a powerful tool to provide sound scientific bases for decision-making processes. In Portugal, the risk assessment process is in its early years and the lack of multidisciplinary teams of experts is frequently mentioned as the main obstacle to its implementation. Therefore, the majority of the reclamation actions are based on impact assessment studies that usually are characterized by few biological and toxicological considerations. In order to account for some of these constraints, the ecological risk assessment framework proposed by the U.S. Environmental Protection Agency was used to plan the assessment of human and ecological risks posed by the high concentrations of metals scattered in the vicinity of S. Domingos mine, a cuprous pyrite mine located in the Southeast Alentejo (Portugal). This study presents the problem formulation phase of the assessment. It includes all the scientific information available for the area, a conceptual model, and an analysis plan for the risk assessment process. Following a tiered approach, several tasks were planned in order to acquire chemical, toxicological, and ecological information, in order to compensate for the lack of toxicity data for site-specific species.  相似文献   

18.
Current measures used to estimate the risks of toxic chemicals are not relevant to the goals of the environmental protection process, and thus ecological risk assessment (ERA) is not used as extensively as it should be as a basis for cost-effective management of environmental resources. Appropriate population models can provide a powerful basis for expressing ecological risks that better inform the environmental management process and thus that are more likely to be used by managers. Here we provide at least five reasons why population modeling should play an important role in bridging the gap between what we measure and what we want to protect. We then describe six actions needed for its implementation into management-relevant ERA.  相似文献   

19.
This overview paper provides the historical context for the incorporation of lifestage‐specific concerns in human health risk assessment, briefly explains the process employed in a lifestage framework for risk assessment, and discusses the scientific rationale for how utilizing lifestage data will strengthen the overall risk assessment process. This risk assessment approach will add value by: (1) providing a more complete evaluation of the potential for vulnerability at different lifestages, including a focus on the underlying biological events and incorporation of mode of action information related to different critical developmental periods; (2) evaluating the potential for toxicity during all lifestages after early lifestage exposure; (3) reviewing the importance of integrating exposure information and adverse health effects across lifestages; and (4) serving as a basis to extend some aspects of the children's health risk assessment framework to all lifestages. Birth Defects Res (Part B), 2008. © 2008 Wiley‐Liss, Inc.  相似文献   

20.
Regulatory decision-making over the use of products of new technology aims to be based on science-based risk assessment. In some jurisdictions, decision-making about the cultivation of genetically modified (GM) plants is blocked supposedly because of scientific uncertainty about risks to the environment. However, disagreement about the acceptability of risks is primarily a dispute over normative values, which is not resolvable through natural sciences. Natural sciences may improve the quality and relevance of the scientific information used to support environmental risk assessments and make scientific uncertainties explicit, but offer little to resolve differences about values. Decisions about cultivating GM plants will thus not necessarily be eased by performing more research to reduce scientific uncertainty in environmental risk assessments, but by clarifying the debate over values. We suggest several approaches to reveal values in decision-making: (1) clarifying policy objectives; (2) determining what constitutes environmental harm; (3) making explicit the factual and normative premises on which risk assessments are based; (4) better demarcating environmental risk assessment studies from ecological research; (5) weighing the potential for environmental benefits (i.e., opportunities) as well as the potential for environmental harms (i.e., risks); and (6) expanding participation in the risk governance of GM plants. Recognising and openly debating differences about values will not remove controversy about the cultivation of GM plants. However, by revealing what is truly in dispute, debates about values will clarify decision-making criteria.  相似文献   

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