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1.
Reliable measurements of pollutant levels in the vicinity of a toll plaza appear to be rare. In order to assess the exposure of toll booth operators to carbon monoxide, a continuous carbon monoxide monitor was installed at head height in the booth of a medium density traffic lane at the Mariannhill toll plaza, situated on a busy highway near Durban, South Africa. Measurements in excess of 500 ppmv were recorded and the high daily mean carbon monoxide concentrations may account for some of the symptoms such as headaches and general malaise that have been reported by workers in the booths. Generally, carbon monoxide levels recorded far exceed the recommended limit set by the South African authorities. These results have led to recommendations regarding the structure of new and existing toll booths to minimize the exposure of toll booth workers to adverse effects of vehicle-emitted pollutants.  相似文献   

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3.
Weather anomalies have a range of adverse contemporaneous impacts on health and socio-economic outcomes. This paper tests if temperature anomalies around the time of birth can have long-term impacts on individuals' economic productivity. Using unique data sets on historical weather and earnings, place and date of birth of all 1.5 million formal employees in Ecuador, we find that individuals who have experienced in-utero temperatures that are 1 °C above average are less educated and earn about 0.7% less as adults. Results are robust to alternative specifications and falsification tests and suggest that warming may have already caused adverse long-term economic impacts.  相似文献   

4.
This paper examines the employment impact of British Columbia's revenue-neutral carbon tax implemented in 2008. While all industries appear to benefit from the redistributed tax revenues, the most carbon-intensive and trade-sensitive industries see employment fall with the tax, while clean service industries see employment rise. By aggregating across industries I find the BC carbon tax generated, on average, a small but statistically significant 0.74 percent annual increases in employment over the 2007–2013 period. This paper provides initial evidence showing how a revenue-neutral carbon tax may not adversely affect employment.  相似文献   

5.
This paper provides evidence of market power in the transportation of ethanol used in reformulated gasoline and alternative transportation fuels. I estimate a reduced form model for railroad route-level prices. My identification strategy instruments for railroad entry, controls for selection and explicitly models capacity constraints. A detailed understanding of this industry is important because U.S. environmental policies seek to substantially expand ethanol use. Evidence of market power may alter the types of policies pursued by lawmakers. I find that ethanol shipment prices are lower for more competitive routes. I also find evidence that railroads price discriminate based on environmental regulation at route destinations. Monopolist prices for shipments to carbon monoxide non-attainment areas are 3% higher than shipments to other destinations. This price premium falls sharply with increased competition. This suggests a perverse result where environmental regulation increases the price of a clean input.  相似文献   

6.
Carbon monoxide (CO) in the surface sea waters is produced predominantly by photochemical processes, oxidized by micro-organisms and outgassed to the atmosphere. to assess carbon monoxide flux from the oceans to the atmosphere, the photochemical production and microbial oxidation of carbon monoxide in the oceanic mixed-layer was investigated during several oeanographic cruises and in the laboratory. the photoproduction rate of carbon monoxide was found to be well correlated to the concentration of dissolved organic carbon (DOC) in coastal and open ocean surface waters. Taking a global average carbon monoxide production rate of 10 ± 2 nmole litre-1 (mg DOC hr)-1 in the surface open ocean water, and 25 ± 7 nmole litre-1 (mg DOC hr)-1 in coastal sea water, at cloud-free summer solar noon, the photochemical production of carbon monoxide in the global oceans is estimated to be at a rate of 1200 ± 200 Tg CO y-1. the microbial carbon monoxide turnover time in the mixed-layer was observed to range from hours in a coastal estuary to 16 days in the Pacific along 1057deg; W in dark incubations. Natural sunlight can largely inhibit the microbial consumption of carbon monoxide in surface water. On a global scale, microbial consumption is responsible for the loss of less than 10% of photochemical produced carbon monoxide in the surface ocean. Field measurements have shown that the net transport of carbon monoxide from the euphotic zone to the underlying deeper ocean water is limited and that the overall life time in surface sea waters is less than 3-4 hours. When combined, these field measurements with the photoproduction and microbial consumption rates obtained, we estimate the oceanic flux to the atmosphere is about 1000 ± 200 Tg CO y-1, which represents the largest single source of atmospheric carbon monoxide.  相似文献   

7.
Abstract

Carbon monoxide (CO) in the surface sea waters is produced predominantly by photochemical processes, oxidized by micro-organisms and outgassed to the atmosphere. to assess carbon monoxide flux from the oceans to the atmosphere, the photochemical production and microbial oxidation of carbon monoxide in the oceanic mixed-layer was investigated during several oeanographic cruises and in the laboratory. the photoproduction rate of carbon monoxide was found to be well correlated to the concentration of dissolved organic carbon (DOC) in coastal and open ocean surface waters. Taking a global average carbon monoxide production rate of 10 ± 2 nmole litre?1 (mg DOC hr)?1 in the surface open ocean water, and 25 ± 7 nmole litre?1 (mg DOC hr)?1 in coastal sea water, at cloud-free summer solar noon, the photochemical production of carbon monoxide in the global oceans is estimated to be at a rate of 1200 ± 200 Tg CO y?1. the microbial carbon monoxide turnover time in the mixed-layer was observed to range from hours in a coastal estuary to 16 days in the Pacific along 1057deg; W in dark incubations. Natural sunlight can largely inhibit the microbial consumption of carbon monoxide in surface water. On a global scale, microbial consumption is responsible for the loss of less than 10% of photochemical produced carbon monoxide in the surface ocean. Field measurements have shown that the net transport of carbon monoxide from the euphotic zone to the underlying deeper ocean water is limited and that the overall life time in surface sea waters is less than 3-4 hours. When combined, these field measurements with the photoproduction and microbial consumption rates obtained, we estimate the oceanic flux to the atmosphere is about 1000 ± 200 Tg CO y?1, which represents the largest single source of atmospheric carbon monoxide.  相似文献   

8.
Air pollution poses a serious threat to human health in Asia. This study analyzes the association of air pollutants and greenness with incidence rates of allergic rhinitis in Seoul at the administrative district level to gain insight into district-level urban policies to improve public health. A spatial regression model is constructed to investigate the correlation between allergic rhinitis incidence rates and five air pollutants measured at 128 air pollution monitoring stations around Seoul: sulfur dioxide (SO2), particulate matter less than 10 μm (PM10), ozone (O3), nitrogen dioxide (NO2), and carbon monoxide (CO). The allergic rhinitis incidence data are derived from the National Health Insurance Service’s database that includes the number of allergic rhinitis-related clinic visits by the patients over 20 years of age and living in Seoul. A kriging geostatistical interpolation was used to estimate average air pollution level of 423 administrative districts. To assess pollen concentrations that can affect allergic rhinitis, the average normalized difference vegetation index (NDVI) is measured based on the urban greenness. The model, controlling for built environment and socio-economic attributes, identifies the possibility of a weak association between allergic rhinitis incidence rates and carbon monoxide levels. The NDVI value is negatively correlated with allergic rhinitis incidence rates, implying a complicated aspect in relation to the effect of urban greenness.  相似文献   

9.
It is well known that air pollution exerts adverse effects on health and environment. Bal?kesir located in the Marmara region (Turkey) has serious air pollution problems produced by heating in the months of winter. In this study, the effect of exposure to air pollution on hospital admission for respiratory illnesses among children and adults was examined. Epidemiological data from records of hospitals, air pollutants and meteorological data were used. During July 2005–July 2007 period, there was a total of 280,426 hospital admissions for respiratory diseases. In a population-based analysis, 9 children were admitted for asthma, 17 children for acute bronchitis, and 20 children for lower respiratory diseases out of 100 children. There was a significant increase in the hospital admissions for respiratory diseases and air pollutants from October to March. It was concluded that children living in the city suffer from respiratory diseases such as asthma, pneumonia, and lower respiratory diseases. Three factors that account for approximately 90% of total variance of hospital admissions, air pollution, and meteorology were identified by means of principal component factor analysis.  相似文献   

10.
Using a national survey and a discrete choice experiment format, we estimate demand for environmental polices to improve health. We use a richly detailed community-level approach that describes illnesses avoided, premature deaths avoided, policy duration, and the affected population size. We allow preferences for policy attributes to vary systematically with the scenario design, with the source of risk and type of health threat, and with respondent characteristics. Using a willingness to pay (WTP) framework similar to that used for studies of individual risk, we find that omission of illness information leads to an upward bias in estimates of the value of avoided premature deaths and that individuals view avoided deaths and avoided illnesses as substitutes. We also find evidence of strongly diminishing marginal utility in policy scope. Differences in marginal WTP from different sources of risk or types of illness appear very small relative to differences associated with respondent characteristics and/or perceptions. Self-interest strongly dominates altruistic considerations.  相似文献   

11.
Coal power generation is expanding rapidly in India and other developing countries. In addition to consequences for climate change, present-day health externalities may also substantially increase the social cost of coal. Health consequences of air pollution have proven important in studies of developed countries, but, despite clear importance, similarly well-identified estimates are less available for developing countries, and no estimates exist for the important case of coal in India. We exploit panel data on Indian households, matched to local changes in exposure to coal plants. Increased exposure to coal plants is associated with worse respiratory health. Consistent with a causal mechanism, the effect is specific: no effect is seen on diarrhea or fever, and no effect on respiratory health is seen of new non-coal plants. Our result is not due to endogenous avoidance behavior, or to differential trends in determinants of respiratory health, either before the period studied or simultaneously.  相似文献   

12.
地方性砷中毒地区环境砷暴露健康风险研究进展   总被引:2,自引:0,他引:2  
自然因素引起的环境高砷暴露及其健康效应,尤其是饮水型地方性砷中毒是砷污染健康风险评估的基础。总结地方性砷中毒在环境砷暴露的风险识别、暴露途径和暴露与健康效应关系研究中的作用基础上,指出了地方性砷中毒研究中仅强调了饮水污染,关注的暴露途径比较单一,因此,人体多途径联合砷暴露的健康风险评估过程存在较大的不确定性。我国是唯一存在饮水和燃煤2种自然环境高砷暴露的国家,是研究2种类型砷暴露异同的天然场地,然而目前环境高砷的暴露及其健康效应的研究均为独立研究,对燃煤型地方性砷中毒在呼吸链砷暴露风险评估中的作用重视不够。因此,通过开展两种环境砷暴露及其健康效应的综合比较研究,建立呼吸链暴露评估和暴露-健康效应模型,可以为人体多途径联合砷暴露的健康风险研究提供新的依据。  相似文献   

13.
We examine how competition affects toxic industrial releases, using five years of data from thousands of facilities across hundreds of industries. Our main result indicates that competition reduces toxic releases at the facility level. On average, each percentage-point reduction in the Herfindahl Index (HHI) results in a nearly two-percent reduction in a facility׳s toxic releases. At the same time, we find no evidence that competition increases aggregate pollution. Further analysis sheds some light on the mechanisms through which firms reduce pollution releases due to increased competition. In particular, we find suggestive evidence that this relationship is due to both reduced output and increases in abatement. We find no evidence that our result is driven by: consumer aversion to pollution, regulations changing with competition, or technologies introduced by new firms. Taken together, our results indicate that competition may be good, at least for public health in areas near polluting facilities, and fail to provide support for the hypothesis that competition leads to more socially undesirable behavior.  相似文献   

14.
颗粒物的健康损害效应已得到广泛的关注。尤其近年来,国内外学者们针对PM2.5等大颗粒开展了大量的人群流行病学和毒理学研究,健康损害效应的因果关系得到基本确认。然而比PM2.5粒径更小但数量更多的超细颗粒物(UFPs),其暴露特征及对健康影响的贡献值尚不清楚,缺乏统一的检测方法及策略是影响其健康评估的关键因素。因此,本文根据国内外文献,综述了目前超细颗粒物的检测方法、仪器及策略,总结了超细颗粒物评价方法的影响因素及其存在的不足,为超细颗粒物检测方法的进一步研究提供建议和帮助。  相似文献   

15.
• Bioaerosol emitted from farming and composting facilities may pose health risks. • We describe population characteristics around these sites and infer public concern. • Sites were mapped and overlaid with population, demographic and school data. • Approximately 16% of the population and 15% of schools are located near these sites. • More community health studies need to be conducted around these sites. Bioaerosol exposure has been linked to adverse respiratory conditions. Intensive farming and composting facilities are important anthropogenic sources of bioaerosols. We aimed to characterise populations living close to intensive farming and composting facilities. We also infer whether the public are becoming more concerned about anthropogenic bioaerosol emissions, using reports of air pollution related incidents attributed to facilities. We mapped the location of 1,257 intensive farming and 310 composting facilities in England in relation to the resident population and its characteristics (sex and age), area characteristics (deprivation proxy and rural/urban classification) and school locations stratified by pre-defined distance bands from these bioaerosol sources. We also calculated the average number of air pollution related incidents per year per facility. We found that more than 16% of the population and 15% of schools are located within 4,828 m of an intensive farming facility or 4,000 m of a composting facility; few people (0.01%) live very close to these sites and tend to be older people. Close to composting facilities, populations are more likely to be urban and more deprived. The number of incidents were attributed to a small proportion of facilities; population characteristics around these facilities were similar. Results indicate that populations living near composting facilities (particularly>250 to≤4,000 m) are mostly located in urban areas (80%–88% of the population), which supports the need for more community health studies to be conducted. Results could also be used to inform risk management strategies at facilities with higher numbers of incidents.  相似文献   

16.
Previous studies evaluating the welfare cost of air pollution have not paid much attention to its potential effect on mental health and subjective well-being (SWB). This paper attempts to fill the gap by investigating the impact of air pollution on several key dimensions, including mental health status, depressive symptoms, moment-to-moment happiness, and evaluative happiness. We match a nationwide longitudinal survey in China with local air quality and rich weather conditions according to the exact time and place of survey. By making use of variations in exposure to air pollution for the same individuals over time, we show that air pollution reduces hedonic happiness and increases the rate of depressive symptoms, while life satisfaction has little to do with the immediate air quality. Our results shed light on air pollution as an important contributor to the Easterlin paradox that economic growth may not bring more happiness.  相似文献   

17.
生物炭对土壤水肥热效应的影响试验研究   总被引:2,自引:0,他引:2  
本文通过野外大田小区试验以番茄(Lycopersicon esculentum Mill)为供试作物,通过在土壤中施加不同含量生物炭(Biochar)研究生物炭对土壤含水率、有机碳、速效养分含量和土壤温度的影响,从而寻求一个较为合适的施用量,为生物炭在内蒙古地区的大面积推广提供科学的理论依据。试验共设5个处理,3个重复:不施加生物炭(CK),生物炭使用量分别为10 t·hm^-2(A),20 t·hm^-2(B),40 t·hm^-2(C),60 t·hm^-2(D),在各生育期取土样测定土壤含水率、有机碳、速效养分含量,并在各生育期连续3天测定土壤地表温度。试验结果表明:不同处理下土壤含水率随生物炭施用量增加呈先增加后减小的趋势,且均高于对照组,其中施炭量为40 t·hm^-2处理的土壤含水率增幅最明显,0~10 cm土层各生育期土壤含水率较对照组最大增幅分别为20.8%、13.7%、21.8%,10~20 cm土层各生育期土壤含水率较对照组最大增幅分别为33.9%、17.1%、21.3%;不同处理下土壤温度随着生物炭施用量的增加而升高,两者具有显著的正相关关系,各生育期各处理土壤地表温度较对照组最大增幅分别为58.1%、31.3%、55.8%;不同处理土壤有机碳含量随着生物炭施用量的增加而增大,番茄各生育期各处理土壤有机碳含量较对照组最大增幅分别为80.9%、62.7%、63.9%;不同处理土壤中碱解氮、速效钾、速效磷含量均随生物炭施用量的增加而呈现先增大后减小的趋势,且均大于对照组,各生育期各处理土壤碱解氮较对照组最大增幅分别为92.7%、45.7%、106.5%,速效磷最大增幅分别为120.1%、39.3%、250.4%,速效钾最大增幅分别为86.2%、118.5%、203.4%。综上所述,生物炭对于砂壤土具有保水、保肥、保温的特性,对于提高土壤水肥利用效率,增加土壤有机碳具有重要的作用,而且通过试验验证40 t·hm^-2的施?  相似文献   

18.
为了定量分析大气总悬浮颗粒物(TSP)对居民呼吸系统疾病死亡率的影响,采用单因素泊松(Poisson)回归分析法,研究了辽宁省抚顺市城区TSP浓度变化与市区1999~2003年呼吸系统疾病死亡率的相关关系.结果发现,在消除了时间、气象等因素影响后,滞后4日TSP浓度每增加50μg·m-3,呼吸系统疾病总人群组死亡率相对危险度(OR)增加1.02195(95%CI=1.00195~1.04245),即滞后4日TSP浓度变化造成总人群组呼吸系统疾病死亡率明显增加的超额死亡率为2.195%.抚顺城区大气TSP污染可能是市区居民呼吸系统疾病死亡率增加的原因之一.  相似文献   

19.
Time discounting is central to the valuation of future health and mortality risks in public sector allocative decision-making, particularly for environmental policies with delayed health impacts. Using a Risk-Risk trade-off survey, we elicit discount rates for fatality risks and establish discounting functional forms on both a sample and an individual level. We find wide variation in implicit discount rates for fatality risk between individuals, as well as between-individual heterogeneity in discounting functional forms. In aggregate, the sample is best characterised by subadditive discounting. Our work has implications for the academic investigation of intertemporal choice involving mortality risks, and potentially for the evaluation of policy options with delayed mortality risk outcomes. A thought experiment cautions against the standard practice of assuming that exponential discounting characterises society's time preferences.  相似文献   

20.
Experiments in which organisms are reared in treatments simulating current and future pCO2 concentrations are critical for ocean acidification (OA) research. The majority of OA exposure experiments use average atmospheric pCO2 levels as a baseline treatment. We conducted an ecoregion-scale analysis of global carbon chemistry datasets. For many locales, atmospheric pCO2 levels are not an appropriate characterization of marine carbon chemistry. We argue that atmospheric pCO2 should be disregarded when setting baseline treatment conditions and experimental design should rely on measurements of carbon chemistry in a study subject’s habitat. As carbon chemistry conditions vary with space and time, we suggest using a range of pCO2 values as a control rather than a single value. We illustrate this issue with data on the habitat of Euphausia pacifica, which currently lives in waters with a pCO2 around 900 μatm, a concentration much higher than the current global atmospheric mean.  相似文献   

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