Variations in Concepts of "Susceptibility" in Risk Assessment

The Food Quality Protection Act and the 1996 amendments to the Safe Drinking Water Act are two of the most recent examples of legislation calling for protection of susceptible subpopulations. As regulatory deadlines draw nearer, controversies in scientific and policy arenas increase about incorporating susceptibility in risk assessment. The previously accepted working definition of "susceptibility" has already been called into question. Part of the controversy results from different disciplines conceiving of susceptibility in different ways. Understanding the conceptual differences embodied within definitions can provide a basis on which a revised working definition may be developed across disciplines. The purposes of this article are to describe the varying definitions of susceptibility, discuss the differing concepts incorporated in the definitions, and recommend ways in which susceptibility may be defined and framed to meet current risk assessment needs. The present analysis of definitions from the fields of ecology, biology, engineering, medicine, epidemiology, and toxicology revealed different emphases that relate to the underlying perspectives and methods of each field. It is likely that susceptibility will need to be formally defined for public policy purposes, but until that time, the use of more informal communication and decision-making processes is suggested to develop and utilize a new working consensus on the definition of susceptibility.     

The Commission White Paper on a Strategy for a Future EU Chemicals Policy: The View of European Companies of American Parentage

After years of good service, EU legislation on chemicals is currently subject to a major review. This process, initiated by the Council of Ministers at Chester in April 1998, will soon lead to new legislative proposals. In the meantime, a review of the Commission's White Paper on "Strategy for a Future Chemicals Policy," published in February 2001, clearly shows that the regulatory landscape in this area will be significantly reshaped and that a new burden will be imposed on industry to demonstrate that the production and use of chemicals indeed conform to high standards of protection of human health and the environment. In the view of industry, on both sides of the Atlantic, while the objectives of the proposed reform can be supported, the measures proposed in the White Paper to implement these objectives are not properly balanced and will lead to substantial societal and economic drawbacks, unless significant adjustments are made. The purpose of this article is to present the pitfalls and difficulties of the reform as they are perceived by the EU Committee of the American Chamber of Commerce in Brussels, an organization that regroups about 150 European companies of American parentage, belonging to a broad range of European business sectors, including producers and users of chemicals. In view of the transatlantic and cross-business character of its membership, the EU Committee offers a different perspective on the debate.     

Upstream Oversight Assessment for Agrifood Nanotechnology: A Case Studies Approach

Although nanotechnology is broadly receiving attention in public and academic circles, oversight issues associated with applications for agriculture and food remain largely unexplored. Agrifood nanotechnology is at a critical stage in which informed analysis can help shape funding priorities, risk assessment, and oversight activities. This analysis is designed to help society and policymakers anticipate and prepare for challenges posed by complicated, convergent applications of agrifood nanotechnology. The goal is to identify data, risk assessment, regulatory policy, and engagement needs for overseeing these products so they can be addressed prior to market entry. Our approach, termed upstream oversight assessment (UOA), has potential as a key element of anticipatory governance. It relies on distinct case studies of proposed applications of agrifood nanotechnology to highlight areas that need study and attention. As a tool for preparation, UOA anticipates the types and features of emerging applications; their endpoints of use in society; the extent to which users, workers, ecosystems, or consumers will be exposed; the nature of the material and its safety; whether and where the technologies might fit into current regulatory system(s); the strengths and weaknesses of the system(s) in light of these novel applications; and the possible social concerns related to oversight for them.     

Assessments of Direct Human Exposure—The Approach of EU Risk Assessments Compared to Scenario-Based Risk Assessment

The awareness of potential risks emerging from the use of chemicals in all parts of daily life has increased the need for risk assessments that are able to cover a high number of exposure situations and thereby ensure the safety of workers and consumers. In the European Union (EU), the practice of risk assessments for chemicals is laid down in a Technical Guidance Document; it is designed to consider environmental and human occupational and residential exposure. Almost 70 EU risk assessment reports (RARs) have been finalized for high-production-volume chemicals during the last decade. In the present study, we analyze the assessment of occupational and consumer exposure to trichloroethylene and phthalates presented in six EU RARs. Exposure scenarios in these six RARs were compared to scenarios used in applications of the scenario-based risk assessment approach to the same set of chemicals. We find that scenarios used in the selected EU RARs to represent typical exposure situations in occupational or private use of chemicals and products do not necessarily represent worst-case conditions. This can be due to the use of outdated information on technical equipment and conditions in workplaces or omission of pathways that can cause consumer exposure. Considering the need for exposure and risk assessments under the new chemicals legislation of the EU, we suggest that a transparent process of collecting data on exposure situations and of generating representative exposure scenarios is implemented to improve the accuracy of risk assessments. Also, the data sets used to assess human exposure should be harmonized, summarized in a transparent fashion, and made accessible for all risk assessors and the public.     

系统风险的会计决定:企业财务风险、经营风险、系统风险的时变关联

新企业会计准则的颁布有力推进了我国金融工具信息披露制度建设,但是到目前为止,研究者对会计信息和上市公司系统风险的关系还不是很清楚.本文提出了新的经济理论模型用于研究财务风险、经营风险和系统风险的动态关联.主要结论:一、财务杠杆和经营杠杆以乘子的形式放大了无杠杆条件下的企业系统风险,这一结论在时变的条件下仍成立;二、理论证实了无杠杆条件下的企业系统风险来源于公司净利润-流通市值比率、销售增长率和平均价格增长率的变动;三、财务风险和经营风险间存在一个权衡,例如经营风险高的公司,将会选择一个较低的财务风险,使得公司有一个相对合理的系统风险.因此,会计风险披露制度的推进可以为投资者提供更多和更好的有关公司风险的信息.     

Categorizing Mistaken False Positives in Regulation of Human and Environmental Health

One of the concerns often voiced by critics of the precautionary principle is that a widespread regulatory application of the principle will lead to a large number of false positives (i.e., over-regulation of minor risks and regulation of nonexisting risks). The present article proposes a general definition of a regulatory false positive, and seeks to identify case studies that can be considered authentic regulatory false positives. Through a comprehensive review of the science policy literature for proclaimed false positives and interviews with authorities on regulation and the precautionary principle we identified 88 cases. Following a detailed analysis of these cases, we found that few of the cases mentioned in the literature can be considered to be authentic false positives. As a result, we have developed a number of different categories for these cases of "mistaken false positives," including: real risks, "The jury is still out," nonregulated proclaimed risks, "Too narrow a definition of risk," and risk-risk tradeoffs. These categories are defined and examples are presented in order to illustrate their key characteristics. On the basis of our analysis, we were able to identify only four cases that could be defined as regulatory false positives in the light of today's knowledge and recognized uncertainty: the Southern Corn Leaf Blight, the Swine Flu, Saccharin, and Food Irradiation in relation to consumer health. We conclude that concerns about false positives do not represent a reasonable argument against future application of the precautionary principle.     

食品安全"监管困局"、 信号扭曲与制度安排

在既有研究提出的食品安全"监管困局"现象基础上,通过仿真建模及分析进一步解剖该困局的动态形成过程,构建食品市场中生产者、消费者和监管者构成的两期博弈模型,剖析食品安全"监管困局"的内在形成机理.研究发现:1)加大监管力度形成的违规揭露信息会影响到消费者的支付预期,当违规揭露水平超过消费者心理承受时会降低消费者的支付水平,进而影响食品行业平均收益,导致生产经营者的超额违规收益迅速增大,反过来又增强了生产经营者的违规动机,是为食品安全"监管困局"的动态形成过程;2)食品安全"监管困局"在于监管者与企业、监管者与消费者两种信息结构使监管力度的信号被扭曲所致,即政府监管力度对消费者形成信号扭曲,消费者无法通过市场价格实现质量信号分离,从而降低支付水平而影响行业平均收益.本文由此提出针对性的制度安排.     

不同“融资铜”模式的风险识别与警示

针对现实中防范"融资铜"风险的需要,本文归纳提炼出三种不同的"融资铜"模式,并就其操作过程中所面临的利率风险、人民币价格波动风险和标的物价格波动风险及其联动性进行深入剖析;采用GARCH-Copula模型,利用上述风险的收益数据及风险因子数据(2011年5月至2014年4月)对单一风险及综合风险进行识别与模拟,对不同模式中综合风险分布进行对比分析,根据在险价值做出警示。结果表明:"融资铜"是一种套利行为,其综合风险收益具有右偏特性,并明显呈现出尖峰厚尾的风险分布特征,相同置信水平下在险价值显著高于单一风险在险价值;其存在极值损失,发生极值损失对企业自身及金融系统会造成严重影响,因此相关监管机构必须对"融资铜"加以重视并实施控制,以引导资金回归实体经济之中。     

基于危机条件概率的系统性风险度量研究

2007年次贷危机的爆发，令系统性风险的度量受到了广泛关注，但是目前常用的度量方法存在多种问题，不能较好地反映金融业系统性风险的实时变化。本文提出一种新的系统性风险度量方法——危机条件概率（Conditional Probability of Crisis，CPC），将系统性风险定义为单个金融机构发生危机导致整个金融系统也陷入危机的概率，可以利用股票收益的下尾相关性计算得出。该方法概念清晰，较好地体现了系统性风险的内涵，并且可得到实时更新的系统性风险。实证基于中国49家上市金融机构的股票价格数据，得出了2007-2016年我国金融业及金融子行业系统性风险。结果显示：2014年下半年以来，中国整个金融行业的系统性风险呈明显上升的趋势，目前甚至已经显著高于次贷危机时期；证券业系统性风险在样本时间范围内一直呈显著上升趋势；银行业对金融行业的影响最大，证券业和保险业的影响力也在逐步上升。     

The Role of Cancer Risk in the Regulation of Industrial Pollution

The extent of carcinogen regulation under existing U.S. environmental statutes is assessed by developing measures of the scope and stringency of regulation. While concern about cancer risk has played an important political role in obtaining support for pollution control programs, it has not provided the predominant rationale for most regulatory actions taken to date. Less than 20% of all standards established to limit concentrations of chemicals in various media address carcinogens. Restrictions on chemical use are more frequently based on concerns about noncancer human health or ecological effects. Of the chemicals in commercial use which have been identified as potential human carcinogens on the basis of rodent bioassays, only a small proportion are regulated. There is an inverse relationship between the scope of regulatory coverage and the stringency of regulatory requirements: the largest percentages of identified carcinogens are affected by the least stringent requirements, such as information disclosure. Standards based on de minimis cancer risk levels have been established for only 10% of identified carcinogens and are restricted to one medium: water. Complete bans on use have affected very few chemicals. The general role that carcinogenicity now plays in the regulatory process is not dramatically different from that of other adverse human health effects: if a substance is identified as a hazard, it may eventually be subject to economically achievable and technically feasible restrictions.     

Chemical and Radiation Environmental Risk Management: Differences, Commonalities, and Challenges

Driven by differing statutory mandates and programmatic separation of regulatory responsibilities between federal, state, and tribal agencies, distinct chemical and radiation risk management strategies have evolved. In the field this separation poses real challenges since many of the major environmental risk management decisions we face today require the evaluation of both types of risks. Over the last decade, federal, state, and tribal agencies have continued to discuss their different approaches and explore areas where their activities could be harmonized. The current framework for managing public exposures to chemical carcinogens has been referred to as a "bottom up approach." Risk between 10(-4) and 10(-6) is established as an upper bound goal. In contrast, a "top down" approach that sets an upper bound dose limit and couples with site specific As Low As Reasonably Achievable Principle (ALARA), is in place to manage individual exposure to radiation. While radiation risk are typically managed on a cumulative basis, exposure to chemicals is generally managed on a chemical-by-chemical, medium-by-medium basis. There are also differences in the nature and size of sites where chemical and radiation contamination is found. Such differences result in divergent management concerns. In spite of these differences, there are several common and practical concerns among radiation and chemical risk managers. They include 1) the issue of cost for site redevelopment and long-term stewardship, 2) public acceptance and involvement, and 3) the need for flexible risk management framework to address the first two issues. This article attempts to synthesize key differences, opportunities for harmonization, and challenges ahead.     

CRMW风险缓释效用目标跟踪的债券投资组合优化策略研究

为缓释债券市场违约风险,央行着力推进信用风险缓释工具CRMW(信用风险缓释凭证)的发展,关于CRMW风险缓释能力度量及CRMW在债券投资组合中的应用成为了亟待解决的关键问题。为此,本文借鉴CVaR思想提出了“CRMW风险缓释效用”以度量CRMW对债券违约风险缓释能力,借助概率分位点理论定义债券的动态风险并制定了动态风险缓释跟踪目标,基于此跟踪目标探讨带有CRMW的债券投资组合优化策略问题。研究结果表明,在保证目标投资收益率的前提下,债券最优投资组合可达到风险缓释效用的目标,使其同时实现转移风险和保障收益的双重目的,且该投资组合优化策略表现出良好的抗风险性能。     

Peak Exposures in Epidemiologic Studies and Cancer Risks: Considerations for Regulatory Risk Assessment

We review approaches for characterizing “peak” exposures in epidemiologic studies and methods for incorporating peak exposure metrics in dose–response assessments that contribute to risk assessment. The focus was on potential etiologic relations between environmental chemical exposures and cancer risks. We searched the epidemiologic literature on environmental chemicals classified as carcinogens in which cancer risks were described in relation to “peak” exposures. These articles were evaluated to identify some of the challenges associated with defining and describing cancer risks in relation to peak exposures. We found that definitions of peak exposure varied considerably across studies. Of nine chemical agents included in our review of peak exposure, six had epidemiologic data used by the U.S. Environmental Protection Agency (US EPA) in dose–response assessments to derive inhalation unit risk values. These were benzene, formaldehyde, styrene, trichloroethylene, acrylonitrile, and ethylene oxide. All derived unit risks relied on cumulative exposure for dose–response estimation and none, to our knowledge, considered peak exposure metrics. This is not surprising, given the historical linear no‐threshold default model (generally based on cumulative exposure) used in regulatory risk assessments. With newly proposed US EPA rule language, fuller consideration of alternative exposure and dose–response metrics will be supported. “Peak” exposure has not been consistently defined and rarely has been evaluated in epidemiologic studies of cancer risks. We recommend developing uniform definitions of “peak” exposure to facilitate fuller evaluation of dose response for environmental chemicals and cancer risks, especially where mechanistic understanding indicates that the dose response is unlikely linear and that short‐term high‐intensity exposures increase risk.     

The Use of Individual and Societal Risk Criteria Within the Dutch Flood Safety Policy—Nationwide Estimates of Societal Risk and Policy Applications

The Dutch government is in the process of revising its flood safety policy. The current safety standards for flood defenses in the Netherlands are largely based on the outcomes of cost‐benefit analyses. Loss of life has not been considered separately in the choice for current standards. This article presents the results of a research project that evaluated the potential roles of two risk metrics, individual and societal risk, to support decision making about new flood safety standards. These risk metrics are already used in the Dutch major hazards policy for the evaluation of risks to the public. Individual risk concerns the annual probability of death of a person. Societal risk concerns the probability of an event with many fatalities. Technical aspects of the use of individual and societal risk metrics in flood risk assessments as well as policy implications are discussed. Preliminary estimates of nationwide levels of societal risk are presented. Societal risk levels appear relatively high in the southwestern part of the country where densely populated dike rings are threatened by a combination of river and coastal floods. It was found that cumulation, the simultaneous flooding of multiple dike rings during a single flood event, has significant impact on the national level of societal risk. Options for the application of the individual and societal risk in the new flood safety policy are presented and discussed.     

Expert Judgment in Risk Analysis and Management: Process, Context, and Pitfalls

The regulation and management of hazardous industrial activities increasingly rely on formal expert judgment processes to provide wisdom in areas of science and technology where traditional "good science" is, in practice, unable to supply unambiguous "facts." Expert judgment has always played a significant, if often unrecognized, role in analysis; however, recent trends are to make it formal, explicit, and documented so it can be identified and reviewed by others. We propose four categories of expert judgment and present three case studies which illustrate some of the pitfalls commonly encountered in its use. We conclude that there will be an expanding policy role for formal expert judgment and that the openness, transparency, and documentation that it requires have implications for enhanced public involvement in scientific and technical affairs.     

不同新能源汽车补贴政策对市场稳定性的影响

目前,加快产业结构升级、形成新的经济增长点的需求,催生各国政府推出各种优化补贴政策以支持新能源汽车产业发展。针对新能源汽车补贴政策优化的问题,本文基于动力系统分支理论构建动态博弈模型,讨论了三种新能源汽车补贴,包括：1）研发补贴;2）市场补贴;3）混合补贴对市场稳定性的影响。结果表明：首先,新能源汽车研发补贴能刺激企业研发投入,但补贴的增加会降低市场稳定性;其次,新能源汽车市场补贴对企业研发投入的刺激效果弱于研发补贴,过度补贴会降低市场稳定性;最后,新能源汽车混合补贴下,研发补贴对企业研发投入的刺激效果优于市场补贴,对企业利润的刺激效果劣于市场补贴,对新能源汽车市场稳定性的提升优于市场补贴。基于此,本文认为增加对其他技术路线以及高端产品的市场补贴,未来对应企业的研发投入进行"研发投入间隔梯度补贴",降低企业研发投入调整速度,以维护市场稳定,促进新能源汽车产业发展。     

基于策略消费者行为和市场细分的联合定价库存策略

策略消费者的行为越来越受到厂商的重视,本文在假设消费者为风险规避型,对商品评价异质,考虑策略消费者和非策略消费者并存的细分市场上,比较两阶段定价和单一定价的优劣,研究限量策略实施的条件,进一步扩展至厂商能同时决定库存和价格的情况。研究表明消费者为风险规避型时,两阶段定价策略优于单一定价策略;策略消费者所占比例越大,消费者风险规避程度越高,第二阶段价格折扣越大,厂商越青睐限量的两阶段定价策略。此外,制定适度的价格折扣才会使厂商增加利润,过度的折扣竞争对厂商和消费者都没有好处。     

系统风险冲击、企业创新能力与股票价格波动性:理论与实证

系统风险冲击和企业创新能力通过影响企业经营基本面和投资者行为而对股票价格波动性产生影响。本文首先建立数学模型从理论上研究系统风险冲击和企业创新能力对股票价格波动性的影响机理;然后以中国A股上市公司2013-2017年期间的相关数据为样本,以2013-2017年期间中国沪深300指数跌幅超过18%的持续性下跌为系统风险冲击源,从创新投入、创新产出和创新环境三个维度构建创新能力指标,采用层次回归分析方法对理论模型结果进行实证检验。研究发现,股票价格波动性与系统风险冲击正相关,与企业创新能力负相关,企业创新能力能够弱化系统风险冲击对股票价格波动性的影响,进而增强股票市场稳定性。规范市场监管行为、改革上市和退市制度、优化创新激励机制、完善上市公司信息披露制度是降低系统风险冲击影响、保障股票市场稳定发展的重要途径。     

A Quantitative Release Assessment for the Noncommercial Movement of Companion Animals: Risk of Rabies Reintroduction to the United Kingdom

In 2004, the European Union (EU) implemented a pet movement policy (referred to here as the EUPMP) under EU regulation 998/2003. The United Kingdom (UK) was granted a temporary derogation from the policy until December 2011 and instead has in place its own Pet Movement Policy (Pet Travel Scheme (PETS)). A quantitative risk assessment (QRA) was developed to estimate the risk of rabies introduction to the UK under both schemes to quantify any change in the risk of rabies introduction should the UK harmonize with the EU policy. Assuming 100 % compliance with the regulations, moving to the EUPMP was predicted to increase the annual risk of rabies introduction to the UK by approximately 60‐fold, from 7.79 × 10^?5 (5.90 × 10^?5, 1.06 × 10^?4) under the current scheme to 4.79 × 10^?3 (4.05 × 10^?3, 5.65 × 10^?3) under the EUPMP. This corresponds to a decrease from 13,272 (9,408, 16,940) to 211 (177, 247) years between rabies introductions. The risks associated with both the schemes were predicted to increase when less than 100 % compliance was assumed, with the current scheme of PETS and quarantine being shown to be particularly sensitive to noncompliance. The results of this risk assessment, along with other evidence, formed a scientific evidence base to inform policy decision with respect to companion animal movement.