Ecological risk assessment in legislation on contaminated soil in The Netherlands

Recently the Dutch soil policy was revised including new rules for the relocation of contaminated soil and dredged soil material. With these rules, new methods for ecotoxicological risk assessment were implemented. One of the new methods is the assessment of the local toxic pressure of mixtures, also known as the ms-PAF- method, based on the Species Sensitivity Distribution concept. The ms-PAF method is applied for risk assessment of spreading of dredged soil material on adjacent land. Its application will possibly be extended to the derivation of local soil quality standards relevant in the context of soil relocation. The application of the local toxic pressure will probably increase the reuse of contaminated soil and dredged soil material and hence will reduce the amounts considered to be unfit for use. With this method, local ecological risk limits are derived using pore water concentrations and effects on water organisms. Pore water concentrations are subsequently transferred to total soil concentrations using empirical relationships. The methodology does not impose upper limits for total soil concentrations. In soils with a high sorption capacity, total soil concentrations that are considered to be acceptable may be several times higher than the current Dutch intervention values. The possible introduction of the ms-PAF method will open the door to local soil relocation with soils containing large amounts of (semi-permanently soil bound) contaminants. Since the ms-PAF method is not yet properly validated, the lack of evidence of ecological effects using models like the ms-PAF method cannot be regarded as an indication for the absence of effects in reality. The Dutch soil quality decree would gain environmental ambition when the ms-PAF method was combined with a realistic upper limit on total soil concentrations. This would prevent contamination of land by means of soil relocation.     

Development of a site-specific ecological risk assessment for contaminated sites: part I. A multi-criteria based system for the selection of ecotoxicological tests and ecological observations

A two modules Decision Support System (DSS-ERAMANIA) was developed in order to support the site-specific Ecological Risk Assessment (ERA) for contaminated sites. Within the first module, the TRIAD and the Weight of Evidence approaches were used to develop a site-specific Ecological Risk Assessment framework including three tires of investigation. Selected ecological observations and ecotoxicological tests were compared according to Multi Criteria Decision Analysis (MCDA) methods and expert judgment, and the obtained ranking was used to identify a suitable set of tests, at each investigation tier, to be applied to the examined case study. A simplified application of the proposed methodology, implemented in the Module 1 of the DSS-ERA-MANIA, is described and discussed.     

Development of a site-specific Ecological Risk Assessment for contaminated sites: part II. A multi-criteria based system for the selection of bioavailability assessment tools

A comparison procedure based on Multi-Criteria Decision Analysis (MCDA) and expert judgment was developed in order to allow the comparison of bioavailability tests to implement the chemical Line of Evidence (LoE) within a TRIAD based site-specific Ecological Risk Assessment framework including three tires of investigation. The proposed methodology was included in the Module 1 of the Decision Support System DSS-ERAMANIA and the obtained rank supported the selection of a suitable set of available tests to be applied to the case study. A simplified application of the proposed procedure is described and results obtained by the system software are discussed.     

Ecological food web analysis for chemical risk assessment

Food web analysis can be a critical component of ecological risk assessment, yet it has received relatively little attention among risk assessors. Food web data are currently used in modeling bioaccumulation of toxic chemicals and, to a limited extent, in the determination of the ecological significance of risks. Achieving more realism in ecological risk assessments requires new analysis tools and models that incorporate accurate information on key receptors in a food web paradigm. Application of food web analysis in risk assessments demands consideration of: 1) different kinds of food webs; 2) definition of trophic guilds; 3) variation in food webs with habitat, space, and time; and 4) issues for basic sampling design and collection of dietary data. The different kinds of food webs include connectance webs, materials flow webs, and functional (or interaction) webs. These three kinds of webs play different roles throughout various phases of an ecological risk assessment, but risk assessors have failed to distinguish among web types. When modeling food webs, choices must be made regarding the level of complexity for the web, assignment of species to trophic guilds, selection of representative species for guilds, use of average diets, the characterization of variation among individuals or guild members within a web, and the spatial and temporal scales/dynamics of webs. Integrating exposure and effects data in ecological models for risk assessment of toxic chemicals relies on coupling food web analysis with bioaccumulation models (e.g., Gobas-type models for fish and their food webs), wildlife exposure models, dose-response models, and population dynamics models.     

Ecological vulnerability in risk assessment — A review and perspectives

This paper reviews the application of ecological vulnerability analysis in risk assessment and describes new developments in methodology. For generic non-site-specific assessments (e.g. for the requirements of most European directives on dangerous chemicals) risk is characterised just on the basis of the ratio between an effect indicator and an exposure indicator. However, when the actual risk for a specific ecosystem is desired, the concept of ecological vulnerability may be more appropriate. This calls for a change in thinking, from sensitivity at the organism level to vulnerability at higher organization levels, and thus forms the link from laboratory toxicology to field effects at population, community or ecosystem level. To do so, biological and ecological characteristics of the ecosystems under concern are needed to estimate the ecological vulnerability.In this review we describe different vulnerability analysis methods developed for populations (of a single species), communities (consisting of different populations of species) and ecosystems (community and habitat combined). We also give some examples of methods developed for socio-ecological systems. Aspects that all methods share are the use of expert judgment, the input of stakeholders, ranking and mapping of the results, and the qualitative nature of the results.A new general framework is presented to guide future ecological vulnerability analysis. This framework can be used as part of ecological risk assessment, but also in risk management. We conclude that the further quantification of ecological vulnerability is a valuable contribution to vulnerability assessment.     

Integration of bioavailability, ecology and ecotoxicology by three lines of evidence into ecological risk indexes for contaminated soil assessment

A Weight of Evidence approach was applied to define three integrated effect indexes estimating the impairment on terrestrial ecosystems caused by the stressor(s) of concern. According to a Triad approach, the integrated effect indexes combined the information provided by the measurement endpoints of each line of evidence (chemistry/bioavailability, ecology and ecotoxicology) and allowed to analyse the impairment degree highlighted by each measurement endpoint as difference from the reference condition. Multi-Criteria Decision Analysis (MCDA) was used for the aggregation of the complementary Triad information, including expert judgement and a weighted procedure based on the endpoint sensitivity and the sensitivity of the test for ecosystem effects. The developed methodology was implemented in the DSS-ERAMANIA, Module 2, and is presented in this paper as "Integrated Effect Indexes" (IEI) sub-module. The latter has been preliminary applied to the Acna di Cengio (Italy) contaminated site; the results of this application are presented and discussed.     

Environmental risk assessment of zinc in European freshwaters: A critical appraisal

A risk assessment report (RAR) on zinc and zinc compounds has recently been prepared in the framework of the European Union (EU) Council Regulation 793/93/EEC on Existing Chemicals. The EU Scientific Committee on Human and Environmental Risks (SCHER) has, however, expressed some fundamental, science-based concerns about the approach followed and the conclusions. The main objective of the present study was to assess the potential environmental risks associated with current use patterns of Zn in nine EU river basins in Germany, France and Belgium, thereby using more advanced methodologies which are largely in line with the recommendations made by SCHER. This included (i) avoiding working with measured Zn concentrations from monitoring stations that were potentially influenced by point sources and/or historical contamination, (ii) the full bioavailability normalization of all chronic ecotoxicity data to river basin specific physico-chemistry using biotic ligand models (BLM), prior to deriving predicted no effect concentrations (PNEC) with the species sensitivity distribution (SSD) approach, and (iii) the use of a probabilistic framework for risk characterization. Further, a total risk approach instead of an added risk approach was used, and the PNEC was equated to the HC5-50 without an additional assessment factor. Based on monitoring data we estimated predicted environmental concentrations (PEC) for the different EU river basins between 1.3 and 14.6 µg dissolved Zn/L. PNEC values varied between 22.1 and 46.1 µg dissolved Zn/L. This resulted in deterministic risk characterization ratios (RCR) that were below 1 in all river basins, suggesting that there is no deterministic regional risk associated with current use patterns of Zn in these river basins. With the probabilistic approach we identified rather limited risks, i.e., between < 0.4 and 18.3%. When the EU RAR approach was applied to the same monitoring datasets, deterministic risks were found in different river basins. A detailed analysis showed that this different deterministic conclusion of risk is mainly due to the fact that the EU RAR (i) uses an additional assessment factor of 2 to derive the PNEC and (ii) uses a more conservative approach for implementing bioavailability (BioF approach). We argue that the larger conservatism in the EU RAR mainly originates from decisions made to deal in a pragmatic way with (i) uncertainty related to the across-species extrapolation of BLMs and (ii) the relatively high sensitivity of some multi-species toxicity studies.     

Generic Assessment Criteria for human health risk assessment of potentially contaminated land in China

Generic Assessment Criteria (GAC) are derived using widely applicable assumptions about the characteristics and behaviour of contaminant sources, pathways and receptors. GAC provide nationally consistent guidance, thereby saving money and time. Currently, there are no human health based Generic Assessment Criteria (GAC) for contaminated sites in China. Protection of human health is therefore difficult to ensure and demonstrate; and the lack of GAC makes it difficult to tell if there is potential significant risk to human health unless site-specific criteria are derived. This paper derived Chinese GAC (GAC) for five inorganic and eight organic substances for three regions in China for three land uses: urban residential without plant uptake, Chinese cultivated land, and commercial/industrial using the SNIFFER model. The SNIFFER model has been further implemented with a dermal absorption algorithm and the model default input values have been changed to reflect the Chinese exposure scenarios. It is envisaged that the modified SNIFFER model could be used to derive GAC for more contaminants, more Regions, and more land uses. Further research to enhance the reliability and acceptability of the GAC is needed in regional/national surveys in diet and working patterns.     

Polycyclic aromatic hydrocarbons (PAHs) in urban surface dust of Guangzhou, China: Status, sources and human health risk assessment

Ninety-six urban surface dust samples collected from Guangzhou, a typical urban center in South China, were analyzed for 16 PAHs (2-6 rings). ∑ PAHs concentrations in the urban surface dust ranged from 0.84 to 12.3 μg/g with a mean of 4.80 μg/g. High molecular weight compounds (4-6 rings) contributed to 62 to 94% of ∑ PAHs mass in the surface dust samples. Four hotspots with highest ∑ PAHs were identified via kriging prediction mapping, representing the highly-urbanized regions: central downtown, highway and industrial area. Two major origins of PAHs inputs to urban surface dust were identified as vehicle emissions (51.9%) and coal combustion (26.8%). The 95% UCL of Incremental Lifetime Cancer Risk (ILCR) due to human exposure to urban surface dust PAHs in central South China was 3.03 × 10⁻⁶ for children and 2.92 × 10⁻⁶ for adults.     

城市区域火灾风险评估方法综述

结合火灾风险评估的定义,对城市区域火灾风险评估的概念及发展概况做出明确说明。针对区域火灾风险评估问题,提出了将评估方法划分为基于指标的传统评估法和基于机器学习的现代评估法两大类,分别对两类方法的评估流程进行概括总结并根据评估流程对常用的传统评估方法进行分类归纳。结合目前区域火灾风险评估的国内外现状,对比总结了两类评估方法的特点和适用范围,并展望了未来的研究方向。     

Climatic city: Two centuries of urban planning and climate science in Manchester (UK) and its region

This paper traces the history, and current challenges, of climate science and urban design in Greater Manchester, UK. The Mancunian metropolis is a remarkable example of a ‘climatic city’, one that shapes its climate as much as it is shaped by it. From the efforts to control smoke and clear slums in the 19th century, to today’s race to be at the forefront of ‘green’ and ‘sustainable’ cities, climate is a central actor in Manchester’s history and will likely be so in the near future. We analyse the continuities and inflections of this history of climate science and urban planning in the metropolis by drawing on historical material and interviews with key local stakeholders, to understand the natural, social and political construction of this singular ‘industrial ecology’. Ultimately, we ask whether stakeholders in the Greater Manchester area can overcome existing challenges to go towards a greener, more resilient and sustainable city.     

Ecological network analysis of an urban water metabolic system: Model development, and a case study for Beijing

Using ecological network analysis, we analyzed the network structure and ecological relationships in an urban water metabolic system. We developed an ecological network model for the system, and used Beijing as an example of analysis based on the model. We used network throughflow analysis to determine the flows among components, and measured both indirect and direct flows. Using a network utility matrix, we determined the relationships and degrees of mutualism among six compartments - 1) local environment, 2) rainwater collection, 3) industry, 4) agriculture, 5) domestic sector, and 6) wastewater recycling - which represent producer, consumer, and reducer trophic levels. The capacity of producers to provide water for Beijing decreased from 2003 to 2007, and consumer demand for water decreased due to decreasing industrial and agricultural demand; the recycling capacity of reducers also improved, decreasing the discharge pressure on the environment. The ecological relationships associated with the local environment or the wastewater recycling sector changed little from 2003 to 2007. From 2003 to 2005, the main changes in the ecological relationships among components of Beijing's water metabolic system mostly occurred between the local environment, the industrial and agricultural sectors, and the domestic sector, but by 2006 and 2007, the major change was between the local environment, the agricultural sector, and the industrial sector. The other ecological relationships did not change during the study period. Although Beijing's mutualism indices remained generally stable, the ecological relationships among compartments changed greatly. Our analysis revealed ways to further optimize this system and the relationships among compartments, thereby optimizing future urban water resources development.     

城市燃气管网运行安全风险评估研究进展

从定性、半定量、定量分析及新兴评估方法等方面介绍2009-2018年国内外燃气管网风险评估的研究进展。整理国内外城市燃气管网风险评估的指南标准,总结我国与国外相关规范标准的优缺点。整理相关软件开发情况,分析我国在软件开发方面的不足。对未来研究的发展趋势做出建议,例如加强耦合风险评估、定量评价法的研究,推进GIS的应用等。     

Weight-of-evidence evaluation in environmental assessment: Review of qualitative and quantitative approaches

Assessments of human health and ecological risk draw upon multiple types and sources of information, requiring the integration of multiple lines of evidence before conclusions may be reached. Risk assessors often make use of weight-of-evidence (WOE) approaches to perform the integration, whether integrating evidence concerning potential carcinogenicity, toxicity, and exposure from chemicals at a contaminated site, or evaluating processes concerned with habitat loss or modification when managing a natural resource. Historically, assessors have relied upon qualitative WOE approaches, such as professional judgment, or limited quantitative methods, such as direct scoring, to develop conclusions from multiple lines of evidence. Current practice often lacks transparency resulting in risk estimates lacking quantified uncertainty. This paper reviews recent applications of weight of evidence used in human health and ecological risk assessment. Applications are sorted based on whether the approach relies on qualitative and quantitative methods in order to reveal trends in the use of the term weight of evidence, especially as a means to facilitate structured and transparent development of risk conclusions from multiple lines of evidence.     

基于层次分析和风险矩阵法的城市供水系统风险评估

以J市供水系统为研究对象,运用风险矩阵法和层次分析法对该市供水系统的风险进行了分析.结果表明,J市供水系统的风险等级接近Ⅲ级;原水系统和制水系统的风险等级达到Ⅲ级,且风险因素主要集中在自然因素、基础设施与设备设施三个方面;输配水系统及二次供水系统的风险等级为Ⅱ级,需要加强管理.同时,根据风险评估结果提出了相应的风险对策...     

The assessment of human health impact caused by industrial and civil activities in the Pace Valley of Messina

The impact of industrial and civil activities on an agricultural and residential area is presented in a detailed and global analysis. The examined area is the Pace river valley situated in the northern zone of Messina (Italy). The sources of pollution present in the area are: a Municipal Solid Waste Incinerator operating since 1979, a disused urban solid waste landfill which was used for 30 years, an urban solid waste treatment facility with heavy vehicles traffic, and two open pits for the production of bitumen. Large quantities of toxic, carcinogenic substances and criteria pollutants are released into the environment and represent potential hazards to human health. The analysis is performed using the EHHRA-GIS tool which employs an integrated, multimedia, multi-exposure pathways and multi-receptor risk assessment model that is able to manage all the steps which constitute the human health risk analysis in a georeferenced structure. The transport of pollutants in different environmental media is assessed applying models (AERMOD, GMS, CALINE) that take into account the particular three-dimensional morphology of the terrain. The results obtained, combined with a probabilistic risk assessment and a sensitivity analysis of calculation parameters, are a comprehensive assessment of the total human health risk in the area. Finally human health risks caused by toxic and carcinogenic substances are compared with acceptable legal limits in order to support environmental managers' decisions.     

桥梁顶升施工风险评价

本文通过对桥梁现状的调查,给出了关于桥梁顶升的施工建议。同时在充分了解项目情况和顶升方案之后,结合国内外桥梁顶升相关资料和文献,从顶升方案、顶升设备、自然灾害3个方面进行风险辨识,建立了东江大道公跨铁立交桥桥梁顶升施工风险指标体系,并应用模糊综合评价法计算得出了该项目的风险等级。     

Probabilistic ecological risk assessment of DDTs in the Bohai Bay based on a food web bioaccumulation model

The fugacity-based food web model was developed to simulate the bioaccumulation of dichloro-diphenyl-trichloroethanes (DDTs) in the aquatic ecosystem in the Bohai Bay. The internal exposure levels (IELs) of DDTs in various organism categories were calculated. Monte Carlo-based uncertainty analysis was performed to get the of IEL distributions of DDTs in organisms. Probabilistic ecological risk assessment (ERA) was performed based on IEL distributions and internal species sensitivity distributions (SSDs). The results show that fugacities and bioaccumulation factors (BAFs) generally increased with increasing trophic level in the food web. Octanol-water partition coefficient (K_ow), DDT levels in water and the lipid contents had the greatest influences on IELs in the organism bodies. The ecological risks of DDTs were relatively high. The risk order was p,p′-DDT > p,p′-DDE > p,p′-DDD. At an internal hazard quotient (HQ_int) criterion of 1/5, the risk probabilities were 0.10 (0.055-0.17), 0.079 (0.045-0.13) and 0.053 (0.028-0.092) for p,p′-DDT, p,p′-DDE and p,p′-DDD, respectively. The results from ERA based on the internal exposure approximated those based on external exposure. The food web model is a feasible method to predict the extent of bioaccumulation and IELs of hydrophobic organic pollutants in organisms as a step to evaluate their risk posed on aquatic ecosystems.     

用于模拟建筑火灾的风险分析模型CUrisk的开发和火灾案例分析

加拿大卡尔顿大学开发了火灾风险计算机模型CUrisk，用以评估四层木结构商品建筑的火灾安全设计。该模型包括系统模型和许多子模型。系统模型用于设定风险分析框架及控制子模型数据流。它还负责计算每个火灾场景的生命危险值。其他子模型包括火灾增长、烟气运动、边界失效火灾蔓延、人员反应和疏散以及建筑造价和经济损失等模型。利用子模型的输出数据，系统模型可计算三个决策参数：对生命的预期风险、对受伤情况的预期风险以及消防成本预期。这些参数是以可能的火灾场景及相关概率为基础的。文章简要介绍了CUrisk模型，并介绍了运用该模型对四层商业建筑所进行的多火灾场景风险分析的结果。     

Towards a better modelling and assessment of construction risk: Insights from a literature review

This paper reviews the literature of construction risk modelling and assessment. It also reviews the real practice of risk assessment. The review resulted in significant results, summarised as follows. There has been a major shift in risk perception from an estimation variance into a project attribute. Although the Probability–Impact risk model is prevailing, substantial efforts are being put to improving it reflecting the increasing complexity of construction projects. The literature lacks a comprehensive assessment approach capable of capturing risk impact on different project objectives. Obtaining a realistic project risk level demands an effective mechanism for aggregating individual risk assessments. The various assessment tools suffer from low take-up; professionals typically rely on their experience. It is concluded that a simple analytical tool that uses risk cost as a common scale and utilises professional experience could be a viable option to facilitate closing the gap between theory and practice of risk assessment.