A New Air Quality Perception Scale for Global Assessment of Air Pollution Health Effects

Despite improvements in air quality in developed countries, air pollution remains a major public health issue. To fully assess the health impact, we must consider that air pollution exposure has both physical and psychological effects; this latter dimension, less documented, is more difficult to measure and subjective indicators constitute an appropriate alternative. In this context, this work presents the methodological development of a new scale to measure the perception of air quality, useful as an exposure or risk appraisal metric in public health contexts. On the basis of the responses from 2,522 subjects in eight French cities, psychometric methods are used to construct the scale from 22 items that assess risk perception (anxiety about health and quality of life) and the extent to which air pollution is a nuisance (sensorial perception and symptoms). The scale is robust, reproducible, and discriminates between subpopulations more susceptible to poor air pollution perception. The individual risk factors of poor air pollution perception are coherent with those findings in the risk perception literature. Perception of air pollution by the general public is a key issue in the development of comprehensive risk assessment studies as well as in air pollution risk management and policy. This study offers a useful new tool to measure such efforts and to help set priorities for air quality improvements in combination with air quality measurements.     

Examining Localized Patterns of Air Quality Perception in Texas: A Spatial and Statistical Analysis

Environmental and human health issues associated with outdoor air pollution, such as ozone, sulfur dioxide, and other pollutants in metropolitan regions, are an area of growing concern for both policy officials and the general public. Increasing attention from the news media, new health data, and public debate over the effectiveness of clean air regulations have raised the importance of air quality in the public consciousness. While public perceptions of air quality have been studied thoroughly dating back to the 1960s, little empirical research has been conducted to explain the spatial aspects of these perceptions, particularly at the local level. Although recent studies suggest characteristics of local setting are important in shaping perceptions of air quality, the roles of proximity, neighborhood characteristics, and location have not been clarified. This study seeks to improve understanding of the major factors shaping public perceptions of air quality by examining the spatial pattern of local risk perception, the role of socioeconomic characteristics in forming these perceptions, and the relationship between perceived and scientifically measured air pollution. First, we map the spatial pattern of local air quality perceptions using Geographic Information Systems (GIS) across the Dallas and Houston metropolitan areas. Next, we explain these perceptions through local contextual factors using both bivariate correlations and multivariate regression analysis. Results indicate that perceptions of air quality in the study areas are not significantly correlated with air quality based on readings of air monitoring stations. Instead, perceptions appear to be influenced by setting (urban vs. rural), state identification, access to information, and socioeconomic characteristics such as age, race, and political identification. We discuss the implications of the findings and provide direction on how further research can provide a deeper understanding of the local contextual factors influencing public perceptions.     

城市机动车限行对PM2.5的影响与效果检验

为缓解城市道路拥堵与交通污染问题,全国多地陆续实施机动车限行政策,但针对不同城市不同限行政策对大气污染的影响却鲜有文献研究。根据政策特征,本文将限行政策分为一般限行和特殊限行两类。基于双重差分模型,采用2001-2017年我国各省会城市及直辖市的面板数据,本文分别研究了不同类型的限行政策对城市PM_2.5污染的改善作用。研究发现：首先,机动车PM_2.5排放已经成为了城市PM_2.5排放的主要来源之一,机动车限行措施也越来越多地被运用到治理城市空气污染的过程中;第二,一般限行政策和特殊限行政策均不同程度地缓解了大气污染,但相对而言,特殊限行政策的减排效果更明显;第三,限行政策的力度,如限行区域的相对大小和限制机动车的相对数量均能影响政策效果,一般来说,限行区域越大,限行的车辆越多,减排效果越显著;第四,在剔除特殊样本"北京"和"限购"政策的影响后,限行政策依然有效。本文从机动车PM_2.5排放的角度实证检验了限行政策对大气污染的影响和效果,为政府进一步制定更高效合理的道路交通污染防治措施提供了参考依据。     

Technical Uncertainty in Quantitative Policy Analysis — A Sulfur Air Pollution Example

Expert judgments expressed as subjective probability distributions provide an appropriate means of incorporating technical uncertainty in some quantitative policy studies. Judgments and distributions obtained from several experts allow one to explore the extent to which the conclusions reached in such a study depend on which expert one talks to. For the case of sulfur air pollution from coal-fired power plants, estimates of sulfur mass balance as a function of plume flight time are shown to vary little across the range of opinions of leading atmospheric scientists while estimates of possible health impacts are shown to vary widely across the range of opinions of leading scientists in air pollution health effects.     

空气污染对重污染公司股票价格的影响:基于政策干预视角的经济价值研究

随着经济发展和产业结构调整，社会公众和政府部门对空气污染问题的原因和治理给予了更多关注。空气重污染公司聚焦度陡增，在经营业绩、发展前景和股市表现方面受到不同程度的冲击。本文利用2014—2019年全国地级市层面空气重污染公司的日度非平衡面板数据，研究政策干预视角下空气污染对股票交易的影响及其经济价值。相较人体弹性感知能力，以空气质量等级变化为触发条件的地方政府防治措施能够更精准地对空气污染做出反应，进而通过公司基本面和投资者情绪渠道影响股市交易。实证结果显示，空气质量等级恶化会对空气重污染公司的股价产生非持续性负面影响，且股价的短期下跌伴随换手率上升特点。经济意义检验表明，空气污染与股价短期关系的发现能够指导投资实践以获取经济增益，而空气质量指数具有改进股价预测的潜力。本文的研究对理解政策干预视角下空气污染对股票市场的影响、股价预测和投资组合均具有十分重要的理论和实践意义。     

Comparative Risk and Policy Analysis in Environmental Health

There is increasing interest in the integration of quantitative risk analysis with benefit-cost and cost-effectiveness methods to evaluate environmental health policy making and perform comparative analyses. However, the combined use of these methods has revealed deficiencies in the available methods, and the lack of useful analytical frameworks currently constrains the utility of comparative risk and policy analyses. A principal issue in integrating risk and economic analysis is the lack of common performance metrics, particularly when conducting comparative analyses of regulations with disparate health endpoints (e.g., cancer and noncancer effects or risk-benefit analysis) and quantitative estimation of cumulative risk, whether from exposure to single agents with multiple health impacts or from exposure to mixtures. We propose a general quantitative framework and examine assumptions required for performing analyses of health risks and policies. We review existing and proposed risk and health-impact metrics for evaluating policies designed to protect public health from environmental exposures, and identify their strengths and weaknesses with respect to their use in a general comparative risk and policy analysis framework. Case studies are presented to demonstrate applications of this framework with risk-benefit and air pollution risk analyses. Through this analysis, we hope to generate discussions regarding the data requirements, analytical approaches, and assumptions required for general models to be used in comparative risk and policy analysis.     

Expert Elicitation of the Value per Statistical Life in an Air Pollution Context

The monetized value of avoided premature mortality typically dominates the calculated benefits of air pollution regulations; therefore, characterization of the uncertainty surrounding these estimates is key to good policymaking. Formal expert judgment elicitation methods are one means of characterizing this uncertainty. They have been applied to characterize uncertainty in the mortality concentration‐response function, but have yet to be used to characterize uncertainty in the economic values placed on avoided mortality. We report the findings of a pilot expert judgment study for Health Canada designed to elicit quantitative probabilistic judgments of uncertainties in Value‐per‐Statistical‐Life (VSL) estimates for use in an air pollution context. The two‐stage elicitation addressed uncertainties in both a base case VSL for a reduction in mortality risk from traumatic accidents and in benefits transfer‐related adjustments to the base case for an air quality application (e.g., adjustments for age, income, and health status). Results for each expert were integrated to develop example quantitative probabilistic uncertainty distributions for VSL that could be incorporated into air quality models.     

Experience with urban air pollution in Paterson, New Jersey and implications for air pollution communication

Communication about air pollution can help reduce health risks, but a scattered, largely qualitative literature on air pollution beliefs, attitudes, and behaviors raises questions about its effectiveness. A telephone survey of Paterson, New Jersey (USA) residents tested four hypotheses aimed toward integrating these findings. Self-reported sheltering indoors during high pollution, the recommended strategy, was predicted by perceived air quality and self-reported "sensitivity" to air pollution. Nearly a quarter of the sample reported mandatory outdoor activity (e.g., work) that might increase their exposures, but this factor did not significantly affect self-reported sheltering. Perceptions of air quality did not correlate strongly with official monitoring data (U.S. Air Quality Index (AQI)); even people who regularly sought AQI data relied upon sensory cues to high pollution, and secondarily upon health cues. Use of sensory and health cues, definitions of what makes someone sensitive to air pollution, and (less strongly) definitions of vulnerability to air pollution varied widely. The minority aware of the AQI were more likely to seek it if they had illnesses or saw themselves in the targeted AQI audience, yet less likely if they believed themselves sensitive to pollution. However, their sense of the AQI's match to their own experience was driven by whether they used sensory (yes) or health (no) cues, not by illness status. Some urban residents might not have access to AQI data, but this barrier seems outweighed by need to bridge interpretive gaps over definitions of air pollution, sensory perception, vulnerability, and health consequences.     

Air Pollution and Mortality: Quantification and Valuation of Years of Life Lost

To analyze the loss of life expectancy (LLE) due to air pollution and the associated social cost, a dynamic model was developed that took into account the decrease of risk after the termination of an exposure to pollution. A key parameter was the time constant for the decrease of risk, for which estimates from studies of smoking were used. A sensitivity analysis showed that the precise value of the time constant(s) was not critical for the resulting LLE. An interesting aspect of the model was that the relation between population total LLE and PM2.5 concentration was numerically almost indistinguishable from a straight line, even though the functional dependence was nonlinear. This essentially linear behavior implies that the detailed history of a change in concentration does not matter, except for the effects of discounting. This model was used to correct the data of the largest study of chronic mortality for variations in past exposure, performed by Pope et al. in 1995; the correction factor was shown to depend on assumptions about the relative toxicity of the components of PM2.5. In the European Union, an increment of 1 microg/m3 of PM2.5 for 1 year implies an average LLE of 0.22 days per person. With regard to the social cost of an air pollution pulse, it was found that for typical discount rates (3% to 8% real) the cost was reduced by a factor of about 0.4 to 0.6 relative to the case with zero discount rate, if the value of a life year was taken as given; if the value of a life year was calculated from the "value of statistical life" by assuming the latter as a series of discounted annual values, the cost varied by at most +/-20% relative to the case with zero discount rate. To assess the uncertainties, this study also examined how the LLE depended on the demographics (mortality and age pyramid) of a population, and how it would change if the relative risk varied with age, in the manner suggested by smoking studies. These points were found to have a relatively small effect (compared to the epidemiological uncertainties) on the calculated LLE.     

"Down and Dirty:" The Use and Abuse of Public Trust in Risk Communication

Many recent contributions to risk communication research stress the importance of the element of "trust" in the process of successful communication. This paper uses that theme in considering risk communication within the context of seeking consensus on matters of health and environmental risk controversies through stakeholder negotiation. It suggests that there are very good reasons, based on historical experience, for the parties to mistrust each other deeply in such settings. For example there is abundant evidence involving episodes in which risk promoters have concealed or ignored relevant risk data or simply have sought to advance their own interests by selective use of such data. These well-established practices compound the difficulties other stakeholders face, in all such negotiation, by virtue of the inescapable uncertainties (as well as absence of needed data) inherent in risk assessments. These factors encourage the participants to treat such negotiations as poker games in which bluffing, raising the ante, and calling the perceived bluffs of others are matters of survival. In the end we should recognize the genuine dilemmas that citizens face in trying to figure out who and what to believe in making sensible decisions among the range of risks, benefits, and tradeoffs that confront us.     

Maximizing Health Benefits and Minimizing Inequality: Incorporating Local‐Scale Data in the Design and Evaluation of Air Quality Policies

The U.S. Environmental Protection Agency undertook a case study in the Detroit metropolitan area to test the viability of a new multipollutant risk‐based (MP/RB) approach to air quality management, informed by spatially resolved air quality, population, and baseline health data. The case study demonstrated that the MP/RB approach approximately doubled the human health benefits achieved by the traditional approach while increasing cost less than 20%—moving closer to the objective of Executive Order 12866 to maximize net benefits. Less well understood is how the distribution of health benefits from the MP/RB and traditional strategies affect the existing inequalities in air‐pollution‐related risks in Detroit. In this article, we identify Detroit populations that may be both most susceptible to air pollution health impacts (based on local‐scale baseline health data) and most vulnerable to air pollution (based on fine‐scale PM_2.5 air quality modeling and socioeconomic characteristics). Using these susceptible/vulnerable subpopulation profiles, we assess the relative impacts of each control strategy on risk inequality, applying the Atkinson Index (AI) to quantify health risk inequality at baseline and with either risk management approach. We find that the MP/RB approach delivers greater air quality improvements among these subpopulations while also generating substantial benefits among lower‐risk populations. Applying the AI, we confirm that the MP/RB strategy yields less PM_2.5 mortality and asthma hospitalization risk inequality than the traditional approach. We demonstrate the value of this approach to policymakers as they develop cost‐effective air quality management plans that maximize risk reduction while minimizing health inequality.     

燃煤机组退役与技术升级的减排及经济效益研究——基于鲁棒电源规划的方法

火电行业是中国推行节能减排战略所重点关注的行业之一。为了降低高污染燃煤机组对环境的不利影响，中国近年来出台了一系列的能源政策，鼓励淘汰高污染的燃煤机组或者对其进行超低排放改造的技术升级。本文研究了燃煤机组主动退役及超低排放改造升级的环境及经济的双重效益。基于电源投资规划鲁棒优化的方法，考虑了受不确定的环保税、超低排放机组上网电价的补贴及电能需求影响下的发电机组最优配置问题，构建了含两阶段决策的三层鲁棒优化模型。该模型是一类具有多个不确定场景耦合特征的大规模优化问题。为了求解的便利，采用列与约束生成（column and constraint generation，CCG）算法进行求解。算例分析结果显示，当考虑了燃煤机组主动退役及超低排放改造升级的决策时，本文构建模型所提供的最优电源结构方案能够有效地降低各类污染物的排放，同时提升发电企业的经济性。     

Managing the Maternal Body: A Comprehensive Review and Transdisciplinary Analysis

This paper comprehensively reviews transdisciplinary and critical perspectives on the employed maternal (pregnant and post‐birth) body in the context of management studies. It highlights the disparities between equal opportunities policies and everyday management practices in relation to pregnancy and new motherhood. In so doing, the review examines the contradictions between equal opportunities policies aimed at protecting pregnant and newly maternal employees and the discouraging treatment that such women receive in practice at work. In analysing the disparity between policy and practice, the review identifies gaps within the field of research on the employed maternal body. It then shows how perceptions about the pregnant and newly maternal body are based more on myth than on evidence. In keeping with policies encouraging family friendly working practices and aimed at enhancing parental health, the paper argues that research on the maternal body is integral to management studies.     

The Risk Screening for Indoor Air Pollution Chemicals in Japan

In recent years, public health problems caused by indoor air pollution have been drawing strong public concern in Japan. After conducting extensive exposure assessment, governmental agencies have taken effective measures to solve the problem; for instance, "Guidelines for indoor air quality (IAQ)" of 13 chemicals, for example, formaldehyde, toluene, and xylene, has been established. Thousands of chemicals have been identified in the indoor environment. Priority rating of those chemicals, however, was not based on the health risk level. We developed a risk-screening scheme for indoor air pollution chemicals and analyzed the current status of the risk levels of those chemicals in Japan. We researched scientific knowledge of health hazards and exposure surveys of indoor air pollution chemicals in Japan, and classified those chemicals based on the health risk level estimated from the scheme. The risk levels of 93 chemicals were characterized and six chemicals (formaldehyde, acrolein, 1,4-dichlorobenzene, benzene, tetrachloroethylene, and benzo(a)pyrene) were classified in the highest risk category.     

Local Control Strategy: Simple Analyses of Air Pollution Data Can Reveal Heterogeneity in Longevity Outcomes

Claims from observational studies that use traditional model specification searches often fail to replicate, partially because the available data tend to be biased. There is an urgent need for an alternative statistical analysis strategy, that is not only simple and easily understood but also is more likely to give reliable insights when the available data have not been designed and balanced. The alternative strategy known as local control first generates local, nonparametric effect‐size estimates (fair treatment comparisons) and only then asks whether the observed variation in these local estimates can be predicted from potential confounding factors. Here, we illustrate application of local control to a historical air pollution data set describing a “natural experiment” initiated by the federal Clean Air Act Amendments of 1970. Our reanalysis reveals subgroup heterogeneity in the effects of air quality regulation on elderly longevity (one size does not fit all), and we show that this heterogeneity is largely explained by socioeconomic and environmental confounders other than air quality.     

Air Toxics and Health Risks in California: The Public Health Implications of Outdoor Concentrations

Of the 188 hazardous air pollutants (HAPs) listed in the Clean Air Act, only a handful have information on human health effects, derived primarily from animal and occupational studies. Lack of consistent monitoring data on ambient air toxics makes it difficult to assess the extent of low-level, chronic, ambient exposures to HAPs that could affect human health, and limits attempts to prioritize and evaluate policy initiatives for emissions reduction. Modeled outdoor HAP concentration estimates from the U.S. Environmental Protection Agency's Cumulative Exposure Project were used to characterize the extent of the air toxics problem in California for the base year of 1990. These air toxics concentration estimates were used with chronic toxicity data to estimate cancer and noncancer hazards for individual HAPs and the risks posed by multiple pollutants. Although hazardous air pollutants are ubiquitous in the environment, potential cancer and noncancer health hazards posed by ambient exposures are geographically concentrated in three urbanized areas and in a few rural counties. This analysis estimated a median excess individual cancer risk of 2.7E-4 for all air toxics concentrations and 8600 excess lifetime cancer cases, 70% of which were attributable to four pollutants: polycyclic organic matter, 1,3 butadiene, formaldehyde, and benzene. For noncancer effects, the analysis estimated a total hazard index representing the combined effect of all HAPs considered. Each pollutant contributes to the index a ratio of estimated concentration to reference concentration. The median value of the index across census tracts was 17, due primarily to acrolein and chromium concentration estimates. On average, HAP concentrations and cancer and noncancer health risks originate mostly from area and mobile source emissions, although there are several locations in the state where point sources account for a large portion of estimated concentrations and health risks. Risk estimates from this study can provide guidance for prioritizing research, monitoring, and regulatory intervention activities to reduce potential hazards to the general population. Improved ambient monitoring efforts can help clarify uncertainties inherent in this analysis.     

Labour Economics: History and Theory

Abstract. In recent years, labour economics has been the area of study of most interest to economists, both from the theoretical and practical perspectives. The new field of labour microeconomics and the resultant new approaches that have arisen are a fundamental part of what has recently been called ‘microeconomic foundations’. Despite the newness of this topic, recent developments are in fact the result of phenomena recognized throughout the history of economic thought. This paper begins by analyzing the historical and theoretical origins of labour economics, and provides an overview of labour economics theory during the 1960s. 1970s and 1980s. It goes on to examine the relation between the labour market and technological innovation, and labour policy measures at the microeconomic and macroeconomic levels. Finally, it underscores the need for a theoretical construct that sets Keynesian and neoclassical explanations of unemployment in the same framework as demographic, social, institutional, time and economic factors.