Using city-wide mobile noise assessments to estimate bicycle trip annual exposure to Black Carbon

Several studies have shown that a significant amount of daily air pollution exposure, in particular Black Carbon (BC), is inhaled during bicycle trips. Previously, the instantaneous BC exposure of cyclists was modeled as the sum of a background concentration and a local traffic related component based on a local assessment of traffic noise. We present a fast and low cost methodology to achieve a city-wide assessment of yearly average BC exposure of cyclists along their trips, based on a city-wide mobile noise sensing campaign.The methodology requires participatory sensing measurements of noise, partially combined with BC and/or other air pollutants sensitive to local traffic variations. The combined measurements cover the spatial and meteorological variability and provide the data for an instantaneous exposure model. The mobile noise-only measurements map the full city; and yearly meteorology statistics are used to extrapolate the instantaneous exposure model to a yearly average map of in-traffic air pollution exposure. Less than four passages at each segment along the network with mobile noise equipment are necessary to reach a standard error of 500 ng/m³ for the yearly average BC exposure.A strong seasonal effect due to the BC background concentration is detected. The background contributes only 25% to the total trip exposure during spring and summer. During winter the background component increases to 50–60%. Engine related traffic noise along the bicyclist's route is a valid indicator of the BC exposure along the route, independent of the seasonal background. Low exposure route selection results in an exposure reduction of 35% in winter and 60% in summer, sensitive to the weather conditions, specific trip attributes and the available alternatives.The methodology is relevant for further research into the local effects of air pollution on health. Mobile noise mapping adds local traffic data including traffic dynamics into the air pollution exposure assessments. Local policy makers and urban planners can use the results to support the implementation of low exposure infrastructure, create awareness through route planners and achieve behavioral changes toward active travel modes.     

Measuring combined exposure to environmental pressures in urban areas: an air quality and noise pollution assessment approach

This study presents a methodological scheme developed to provide a combined air and noise pollution exposure assessment based on measurements from personal portable monitors. Provided that air and noise pollution are considered in a co-exposure approach, they represent a significant environmental hazard to public health. The methodology is demonstrated for the city of Thessaloniki, Greece. The results of an extensive field campaign are presented and the variations in personal exposure between modes of transport, routes, streets and transport microenvironments are evaluated. Air pollution and noise measurements were performed simultaneously along several commuting routes, during the morning and evening rush hours. Combined exposure to environmental pollutants is highlighted based on the Combined Exposure Factor (CEF) and Combined Dose and Exposure Factor (CDEF). The CDEF takes into account the potential relative uptake of each pollutant by considering the physical activities of each citizen. Rather than viewing environmental pollutants separately for planning and environmental sustainability considerations, the possibility of an easy-to-comprehend co-exposure approach based on these two indices is demonstrated. Furthermore, they provide for the first time a combined exposure assessment to these environmental pollutants for Thessaloniki and in this sense they could be of importance for local public authorities and decision makers. A considerable environmental burden for the citizens of Thessaloniki, especially for VOCs and noise pollution levels is observed. The material herein points out the importance of measuring public health stressors and the necessity of considering urban environmental pollution in a holistic way.     

A study of effects of ambient urban air pollution using personal samplers; a preliminary report

Air pollution has been associated with an increased incidence of respiratory disease. However, significant differences may exist between air pollution levels measured at conventional fixed monitoring stations and actual levels inhaled by a subject. Furthermore, studies of effects of air pollution might best be done using asthmatics as study subjects, since they have irritable airways. This is a preliminary report of a study using a control and asthmatic group in which effects of air pollution are assessed by sympton and medication diaries and simple pulmonary function tests. Air pollution exposure is measured using a small portable sampler for particulates, SO₂ and NO₂; these samplers are carried by the subject (“personal”) and are situated inside and outside the home. Levels obtained are compared to data obtained from the same type of sampler located at a fixed monitoring station. Preliminary analysis of the data shows that the levels of pollutants are low and there are significant differences between the four air pollution measurements, with weak correlations among the various measurements. In this preliminary report, change in pulmonary function during the day correlates only with personal NO₂ measurements. This suggests the need for estimating air pollution exposure using “personal” samplers, when investigating health effects.     

Future climate and adverse health effects caused by fine particulate matter air pollution: case study for Poland

Ground level air pollution, especially fine particulate matter (PM_2.5), has been associated with a number of adverse health effects. The dispersion of PM_2.5 through the atmosphere depends on several mutually connected anthropogenic, geophysical and meteorological parameters, all of which are affected by climate change. This study examines how projected climate change would affect population exposure to PM_2.5 air pollution in Poland. Population exposure to PM_2.5 in Poland was estimated for three decades: the 1990s, 2040s and 2090s. Future climate conditions were projected by Regional Climate Model RegCM (Beta), forced by the general atmospheric circulation model ECHAM5. The dispersion of PM_2.5 was simulated with chemical transport model CAMx version 4.40. Population exposure estimates of PM_2.5 were 18.3, 17.2 and 17.1 μg/m³ for the 1990s, 2040s and 2090s, respectively. PM_2.5 air pollution was estimated to cause approximately 39,800 premature deaths in the population of Poland in the year 2000. Our results indicate that in Poland, climate change may reduce the levels of exposure to anthropogenic particulate air pollution in future decades and that this reduction will reduce adverse health effects caused by the air pollution.     

Characterizing multi-pollutant air pollution in China: Comparison of three air quality indices

Multi-pollutant air pollution (i.e., several pollutants reaching very high concentrations simultaneously) frequently occurs in many regions across China. Air quality index (AQI) is used worldwide to inform the public about levels of air pollution and associated health risks. The current AQI approach used in China is based on the maximum value of individual pollutants, and does not consider the combined health effects of exposure to multiple pollutants. In this study, two novel alternative indices – aggregate air quality index (AAQI) and health-risk based air quality index (HAQI) – were calculated based on data collected in six megacities of China (Beijing, Shanghai, Guangzhou, Shjiazhuang, Xi'an, and Wuhan) during 2013 to 2014. Both AAQI and HAQI take into account the combined health effects of various pollutants, and the HAQI considers the exposure (or concentration)-response relationships of pollutants. AAQI and HAQI were compared to AQI to examine the effectiveness of the current AQI in characterizing multi-pollutant air pollution in China. The AAQI and HAQI values are higher than the AQI on days when two or more pollutants simultaneously exceed the Chinese Ambient Air Quality Standards (CAAQS) 24-hour Grade II standards. The results of the comparison of the classification of risk categories based on the three indices indicate that the current AQI approach underestimates the severity of health risk associated with exposure to multi-pollutant air pollution. For the AQI-based risk category of ‘unhealthy’, 96% and 80% of the days would be ‘very unhealthy’ or ‘hazardous’ if based on AAQI and HAQI, respectively; and for the AQI-based risk category of ‘very unhealthy’, 67% and 75% of the days would be ‘hazardous’ if based on AAQI and HAQI, respectively. The results suggest that the general public, especially sensitive population groups such as children and the elderly, should take more stringent actions than those currently suggested based on the AQI approach during high air pollution events. Sensitivity studies were conducted to examine the assumptions used in the AAQI and HAQI approaches. Results show that AAQI is sensitive to the choice of pollutant irrelevant constant. HAQI is sensitive to the choice of both threshold values and pollutants included in total risk calculation.     

The rise of low-cost sensing for managing air pollution in cities

Ever growing populations in cities are associated with a major increase in road vehicles and air pollution. The overall high levels of urban air pollution have been shown to be of a significant risk to city dwellers. However, the impacts of very high but temporally and spatially restricted pollution, and thus exposure, are still poorly understood. Conventional approaches to air quality monitoring are based on networks of static and sparse measurement stations. However, these are prohibitively expensive to capture tempo-spatial heterogeneity and identify pollution hotspots, which is required for the development of robust real-time strategies for exposure control. Current progress in developing low-cost micro-scale sensing technology is radically changing the conventional approach to allow real-time information in a capillary form. But the question remains whether there is value in the less accurate data they generate. This article illustrates the drivers behind current rises in the use of low-cost sensors for air pollution management in cities, while addressing the major challenges for their effective implementation.     

崂山风景区旅游环境容量研究

通过对历年游客流量调查，分析了崂山风景区客流时间和空间分布特征。计算了景区9条步道游线，3条索道和7个人文景观区的日容量、月容量和年容量，并分析了景区旅游环境容量的利用强度，发现2004年景区各条步道游线、各条索道和各个人文景观区的日、月、年容量利用强度均为适载，但第一、第二和第三高峰日已严重超载。最后，制定了游客流量宏观调控对策及微观调控措施。     

技术异质下中国大气污染排放效率的区域差异与影响因素

近年来中国雾霾天气的频繁发生给人们的生产、生活以及身体健康构成巨大威胁。提高大气污染排放效率,深入挖掘大气污染减排潜力是改善中国大气环境质量,减少和消除雾霾天气发生的重要途径。本文根据生态效率理论,充分考虑到不同区域发展的不平衡因素与技术异质性特征,在共同前沿方法框架下科学测算2006—2014年间中国30个省份的大气污染排放效率,在此基础上分析效率的区域差异,利用"技术差距比(TGR)"这一指标衡量东部、中部与西部三大区域之间大气污染排放技术的差距,并从"技术"与"管理"两个维度进一步将各省份大气污染排放无效率分解为"技术差距无效率(TGI)"与"管理无效率(GMI)",以此定位各省份大气污染防治的薄弱环节,进而构建策略矩阵,将全国各省份归入四个不同排放效率特征的方阵,并给出相应的优化路径与措施;深入揭示大气污染排放效率与排放强度之间的内在联系,提出"大气污染排放强度效率"这一全新概念并考察其演化趋势;利用面板Tobit回归模型检验影响我国省际大气污染排放效率与排放技术的外部环境因素。实证结果表明:1中国大气污染排放效率整体水平偏低,年均仅为0.493,污染减排潜力巨大;2中国大气污染排放效率与排放技术的地区差异显著,无论是大气污染排放效率还是排放技术水平,东部地区都是明显高于中部与西部地区;3中国大气污染的实际排放强度明显高于潜在排放强度,这表明大气污染排放强度还存在很大的改进空间;4经济发展、产业结构升级与科技创新对大气污染排放效率与排放技术的提升均有显著促进作用,煤炭消费比重上升与人口密度过大则对其有显著抑制作用;5本文的研究结论支持"波特假说"与"污染避难所"假说。     

Residential exposure to traffic noise and risk of incident atrial fibrillation: A cohort study

BackgroundStudies have found long-term exposure to traffic noise to be associated with higher risk for hypertension, ischemic heart disease and stroke. We aimed to investigate the novel hypothesis that traffic noise increases the risk of atrial fibrillation (A-fib).MethodsIn a population-based cohort of 57,053 people aged 50–64 years at enrolment in 1993–1997, we identified 2692 cases of first-ever hospital admission of A-fib from enrolment to end of follow-up in 2011 using a nationwide registry. The mean follow-up time was 14.7 years. Present and historical residential addresses were identified for all cohort members from 1987 to 2011. For all addresses, exposure to road traffic and railway noise was estimated using the Nordic prediction method and exposure to air pollution was estimated using a validated dispersion model. We used Cox proportional hazard model for the analyses with adjustment for lifestyle, socioeconomic position and air pollution.ResultsA 10 dB higher 5-year time-weighted mean exposure to road traffic noise was associated with a 6% higher risk of A-fib (incidence rate ratio (IRR): 1.06; 95% confidence interval (95% CI): 1.00–1.12) in models adjusted for factors related to lifestyle and socioeconomic position. The association followed a monotonic exposure–response relationship. In analyses with adjustment for air pollution, NO_x or NO₂, there were no statistically significant associations between exposure to road traffic noise and risk of A-fib; IRR: 1.04; (95% CI: 0.96–1.11) and IRR: 1.01; (95% CI: 0.94–1.09), respectively. Exposure to railway noise was not associated with A-fib.ConclusionExposure to residential road traffic noise may be associated with higher risk of A-fib, though associations were difficult to separate from exposure to air pollution.     

Health effects for the population living near a cement plant: An epidemiological assessment

Epidemiological studies have shown the association between the exposure to air pollution and several adverse health effects. To evaluate the possible acute health effects of air pollution due to the emissions of a cement plant in two small municipalities in Italy (Mazzano and Rezzato), a case–control study design was used. The risks of hospital admission for cardiovascular or respiratory diseases for increasing levels of exposure to cement plant emissions were estimated, separately for adults (age > 34 years) and children (0–14 years). Odds ratios (OR) were estimated using unconditional regression models. Attributable risks were also calculated.Statistically significant risks were found mainly for respiratory diseases among children: OR 1.67 (95% CI 1.08–2.58) for the moderately exposed category (E1), OR 1.88 (95% CI 1.19–2.97) for the highly exposed category (E2), with an attributable risk of 38% of hospital admissions due to the exposure to cement plant exhausts. Adults had a weaker risk: OR 1.38 (95% CI 1.18–1.61) for group E1, OR 1.31 (95% CI 1.10–1.56) for group E2; the attributable risk was 23%. Risks were higher for females and for the age group 35–64. These results showed an association between the exposure to plant emissions and the risk of hospital admission for cardiovascular or respiratory causes; this association was particularly strong for children.     

The relationship between socio-economic indicators and air pollution in England and Wales: implications for environmental justice

This paper investigates the distribution of three common air pollutants, sulphur dioxide, nitrogen dioxide and fine particulates (PM₁₀), in England and Wales with respect to social class, ethnicity and population density. A multilevel model is used to demonstrate regional differences in the social distribution of pollution. The results show that, allowing for ethnicity and population density, there are different relationships between socio-economic status and exposure to air pollution within different regions in England and Wales. These differences suggest that national legislation introduced to reduce air pollution levels may give rise to environmental injustice, with geographical and social differences in the costs and benefits arising to the population due to such legislation. Received: 24 February 1999 / Accepted: 2 September 1999     

Fertility and air pollution: Some empirical findings

This paper attempts to explain regional differences in fertility rates in the standard metropolitan statistical areas of the United States through socioeconomic factors and air pollution. An important feature of this study is that it uses the most recent data pertaining to a homogeneous sample of observations within a country rather than using data for different countries. Statistical results suggest that given other factors, fertility and the level of air pollution have an inverse relationship. This quantitative effect is statistically significant but the absolute impact is rather low. Our results also suggest that an increase in the level of income, relative education of females, temperature, and the availability of physicians would in the long run reduce fertility rates in the urban areas of the United States.     

Exposure to traffic-related air pollution and the risk of developing breast cancer among women in eight Canadian provinces: A case–control study

A few recent studies have reported positive associations between long-term exposure to traffic-related air pollution and the incidence of breast cancer. We capitalized on an existing Canadian multi-site population-based case–control study to further investigate this association.We used the National Enhanced Cancer Surveillance System, a population-based case–control study conducted in eight of 10 Canadian provinces from 1994 to 1997. A total of 1569 breast cancer cases and 1872 population controls who reported at least 90% complete self-reported addresses over the 1975–1994 exposure period were examined. Mean exposure levels to nitrogen dioxide (NO₂) (an indicator of traffic-related air pollution) were estimated for this period using three different measures: (1) satellite-derived observations; (2) satellite-derived observations scaled with historical fixed-site measurements of NO₂; and (3) a national land-use regression (LUR) model. Proximity to major roads was also examined. Using unconditional logistic regression, stratified by menopausal status, we estimated odds ratios (ORs) adjusted for many individual-level and contextual breast cancer risk factors.We observed positive associations between incident breast cancer and all three measures of NO₂ exposure from 1975 to 1994. In fully adjusted models for premenopausal breast cancer, a 10 ppb increase in NO₂ exposure estimated from the satellite-derived observations, the scaled satellite-derived observations, and the national LUR model produced ORs of 1.26 (95% confidence intervals (CIs): 0.92–1.74), 1.32 (95% CI: 1.05–1.67) and 1.28 (95% CI: 0.92–1.79). For postmenopausal breast cancer, we found corresponding ORs of 1.10 (95% CI: 0.88–1.36), 1.10 (95% CI: 0.94–1.28) and 1.07 (95% CI: 0.86–1.32). Substantial heterogeneity in the ORs was observed across the eight Canadian provinces and reduced ORs were observed when models were restricted to women who had received routine mammography examinations. No associations were found for road proximity measures.This study provides some support for the hypothesis that traffic-related air pollution may be associated with the development of breast cancer, especially in premenopausal women. With the few studies available, further research is clearly needed.     

Inequalities in cumulative environmental burdens among three urbanized counties in California

Low-income communities and communities of color often suffer from multiple environmental hazards that pose risks to their health. Here we extended a cumulative environmental hazard inequality index (CEHII) – developed to assess inequalities in air pollution hazards – to compare the inequality among three urban counties in California: Alameda, San Diego, and Los Angeles. We included a metric for heat stress to the analysis because exposure to excessively hot weather is increasingly recognized as a threat to human health and well-being. We determined if inequalities from heat stress differed between the three regions and if this added factor modified the metric for inequality from cumulative exposure to air pollution. This analysis indicated that of the three air pollutants considered, diesel particulate matter had the greatest inequality, followed by nitrogen dioxide (NO₂) and fine particulate matter (PM_2.5). As measured by our index, the inequalities from cumulative exposure to air pollution were greater than those of single pollutants. Inequalities were significantly different among single air pollutant hazards within each region and between regions; however, inequalities from the cumulative burdens did not differ significantly between any two regions. Modeled absolute and relative heat stress inequalities were small except for relative heat stress in San Diego which had the second highest inequality. Our analysis, techniques, and results provide useful insights for policy makers to assess inequalities between regions and address factors that contribute to overall environmental inequality within each region.     

A procedure to estimate worst-case air quality in complex terrain

Using a straightforward synoptic climatological analysis scheme, it is shown that the potential for an area to experience air quality degradation due to local sources is highest under polar subtropical highs. With respect to polar highs, the problem is most severe when the sun angle is low and snow covers the ground, and the polar high persists for a long period of time. A simple algorithm is introduced which is designed to estimate worst-case impact in a trapping valley. The potential for the accumulation of air pollution in such valleys due to the persistence of a polar high in a region, is ignored in current regulatory air quality assessments. Trapping valleys and synoptic flow stagnation often occur in wilderness areas. Refined air quality assessments are shown to be possible using a mesoscale meteorological model and a pollution dispersion model. These tools permit quantitative assessments of pollution build-up from local sources as a result of the recirculation of the local air. This tool, along with the synoptic climatological classification scheme, also permits an evaluation of the fractional contribution of long range versus local sources in the air quality degradation in a region. Areas near the center of a polar or subtropical surface high pressure system, for instance, appear to be dominated by local sources, if they exist, whereas in the vicinity of extratropical cyclones, long-range transport is usually much more important.     

基于DCCA方法的成都市市区与周边城镇大气污染长程相关性分析

利用2008年1月～2012年12月期间成都市市区与其周边14个城镇的逐日空气污染指数（API）数据,采用去趋势互相关分析法（DCCA分析）研究区域城市间大气污染的相关性及其随时间演变规律。结果表明:成都市区与其周边城镇大气污染的空气污染存在一定程度的相关性,并且在不同的月份,相关性会随之发生变化。这种相关性具有长期持续特征,具体表现为在一定的时间尺度上成都市区与其周边城镇大气污染的相关性随时间的变化并不遵循经典的马尔可夫过程,即不随时间呈现指数快速衰减,而是以幂律形式随时间缓慢衰减。进一步,结合不同月份间区域大气平均流场的分布特征,探讨了DCCA分析结果的科学性。研究结果说明,在特定地理环境和气象条件控制下,成都市及其周边城市之间已经存在明显的相互输送和耦合作用,成都地区大气污染已由局地性污染转变为区域性大气污染。城市间污染物输送的长期相关影响机制极有可能在特定月份加重成都市区的空气污染状况,这在成都市区及其周边城镇的规划建设中必须加以特别重视     

Exploring uncertainty of the change from ICD-9 to ICD-10 on acute mortality effects of air pollution

The change in ICD coding from ICD-9 to ICD-10 may produce inconsistencies and discontinuities in cause-specific mortality, thus impacting on effects estimates of air pollution on mortality. The current study was conducted in Wuhan, China. We examined the concordant rates and Kappa statistics using the mortality data from the year 2002 coded with both ICD-9 and ICD-10 codes and compared the estimated effects of air pollution using the Generalized Additive Model in R. We found high concordant rates (>99.3%) and Kappa statistics close to 1.0 (>0.98). Little difference was identified in the estimated effects of air pollution on daily cardiovascular, stroke, cardiac, cardiopulmonary, and respiratory mortality. This study provides evidence that, based on the wide definitions of cause-specific morality typically used in the studies of time-series air pollution mortality, the change in the ICD coding does not significantly affect the estimated effects of air pollution.     

Inflammatory markers in relation to long-term air pollution

Long-term exposure to ambient air pollution can lead to chronic health effects such as cancer, cardiovascular and respiratory disease. Systemic inflammation has been hypothesized as a putative biological mechanism contributing to these adverse health effects. We evaluated the effect of long-term exposure to air pollution on blood markers of systemic inflammation.We measured a panel of 28 inflammatory markers in peripheral blood samples from 587 individuals that were biobanked as part of a prospective study. Participants were from Varese and Turin (Italy) and Umea (Sweden). Long-term air pollution estimates of nitrogen oxides (NO_x) were available from the European Study of Cohorts for Air Pollution Effects (ESCAPE). Linear mixed models adjusted for potential confounders were applied to assess the association between NO_x and the markers of inflammation.Long-term exposure to NO_x was associated with decreased levels of interleukin (IL)-2, IL-8, IL-10 and tumor necrosis factor-α in Italy, but not in Sweden. NO_x exposure levels were considerably lower in Sweden than in Italy (Sweden: median (5th, 95th percentiles) 6.65 μg/m³ (4.8, 19.7); Italy: median (5th, 95th percentiles) 94.2 μg/m³ (7.8, 124.5)). Combining data from Italy and Sweden we only observed a significant association between long-term exposure to NO_x and decreased levels of circulating IL-8.We observed some indication for perturbations in the inflammatory markers due to long-term exposure to NO_x. Effects were stronger in Italy than in Sweden, potentially reflecting the difference in air pollution levels between the two cohorts.     

Concepts of human exposure to air pollution

In recent years, considerable attention has focused on the concept of “human exposure” to environmental pollutants, but different investigators seem to have developed different definitions of this concept and used different approaches for estimating it. This paper reviews a number of “exposure” studies in a single environmental medium—air pollution—to see how others have defined this concept in the literature. Many previous investigators unfortunately calculate “exposures” by relying on data from fixed air monitoring stations, and they assume that people are located in the same place, usually their residential address, throughout a 24-h period. However, a second body of literature shows that fixed air monitoring stations do not necessarily reflect human exposures, because concentrations observed indoors—in homes, offices, factories, and motor vehicles—differ from those observed at fixed stations, and people usually spend considerable time in these locations. In an effort to standardize the nomenclature dealing with exposures, a definition is proposed in which the pollutant must come into contact with the physical boundary of the person. Then, exposure of person i to pollutant concentration c is viewed as two events occurring jointly: person i is present at a particular location, and concentration c is present at the same location. Mathematical definitions for “integrated exposure,” “average exposure,” and “standardized exposure” with various averaging periods also are introduced. Finally, two different yet compatible research approaches are suggested for determining human exposures to air pollution.     

Outdoor air pollution and term low birth weight in Japan

IntroductionEvidence has accumulated on the association between ambient air pollution and adverse birth outcomes. However, most of the previous studies were conducted in geographically distinct areas and suffer from lack of important potential covariates. We examined the effect of ambient air pollution on term low birth weight (LBW) using data from a nationwide population-based longitudinal survey in Japan that began in 2001.MethodsWe restricted participants to term singletons (n = 44,109). Air pollution concentrations during the 9 months before birth were obtained at the municipality level and were assigned to the participants who were born in the corresponding municipality. We conducted multilevel logistic regression analyses adjusting for individual and municipality-level variables.ResultsWe found that air pollution exposure during pregnancy was positively associated with the risk of term LBW. In the fully adjusted models, odds ratios following one interquartile range increase in each pollutant were 1.09 (95% confidence interval: 1.00, 1.19) for suspended particulate matter (SPM), 1.11 (0.99, 1.26) for nitrogen dioxide (NO₂), and 1.71 (1.18, 2.46) for sulfur dioxide (SO₂). Specifically, effect estimates for SPM and NO₂ exposure at the first trimester were higher than those at other trimesters, while SO₂ was associated with the risk at all trimesters. Nonsmoking mothers were more susceptible to SPM and NO₂ exposure compared with smoking mothers.ConclusionsAmbient air pollution increases the risk of term LBW in a nationally representative sample in Japan.