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Benzene is a volatile organic air pollutant that is ubiquitous in the environment. It is frequently reported in urban airsheds, principally as a result of evaporative emissions from motor vehicles. Increasingly stringent fuel quality standards have resulted in lower mean benzene concentrations in many urban airsheds, however the concentrations reported indoors can be higher than those in urban airsheds. Mean indoor benzene concentrations can reach one order of magnitude higher than those reported in urban airsheds. Long term exposure to very high benzene concentrations can result in leukemia, however the health risks of long term non-industrial exposure in the general public are currently uncertain. An important part of determining the risks of non-industrial benzene exposure is to first determine the influence of various activities on 24-hour personal benzene exposure. Previous research has identified commuting in a private motor vehicle and refuelling with low benzene fuel as statistically significant contributors to nonindustrial benzene exposure in the Northern Hemisphere, however none has quantified the increase in benzene exposure as a result of these activities over a 24-hour period in the Mediterranean climate. The results of the 1987 TEAM study in the South Bay section of California reported that automobile exhaust was a significant contributor to non-industrial benzene exposure based on exhaled breath concentrations (p<0.05) and commuting in a private vehicle (p=0.0003) and refuelling (0.05) were important contributors based on personal benzene exposure concentrations (Wallace et al., 1988). The aims of this thesis were to identify the roles and importance of selected activities in personal exposure to benzene, to determine the increase in 24-hour personal benzene exposure attributable to these activities and quantify the risk posed by these activities in a Mediterranean climate. In particular, the aim of this thesis was to investigate whether commuting in a private motor vehicle and refuelling are significant contributors to non-industrial personal benzene exposure in a Mediterranean climate, or whether lifestyle and climate interact. This research was composed of a personal exposure study, a source monitoring study and a risk assessment. A cross-sectional personal exposure study was conducted for two reasons. Firstly, to quantify the mean personal benzene concentrations to which a representative sample of the general public of Perth was exposed as a result of their daily activities and behaviours. Secondly, to quantify the frequency of commuting by private motor vehicle and refuelling with low benzene fuel in Perth. Fifty participants were recruited for the personal exposure study, and asked to wear a monitor for 24-hour period(including weekends) in summer and winter and record their activities and locations in a diary. Prior to the monitoring they were asked to complete a questionnaire seeking background information on their home, lifestyle and behaviours. The results of the research revealed that there was not a statistically significant difference between the personal benzene exposure concentrations in summer and winter. An analysis of the questionnaire and time activity diary data using a generalised linear mixed model revealed that the time spent commuting in a private motor vehicle (â= 0.281, p<0.0001) and refuelling with low benzene fuel (â = 0.194, p=0.033) were statistically significant contributors to non-industrial benzene exposure. Each hour spent commuting resulted in a mean increase in 24-hour personal exposure of 0.74 ìgm-3 (â= 0.729 ìg m-3, p< 0.0001). The mean increase in exposure per hour of commuting in a private motor vehicle was larger in winter (â= 0.8 ìg m-3, p=0.008) than summer (â= 0.67 ìg m-3, p=0.004). Refuelling increased personal exposure by 1.50 ìg m-3 (1.49, p<0.0001) in each 24-period when refuelling was reported. Benzene source monitoring was conducted at selected locations in Perth for two reasons. Firstly, data quantifying non-industrial personal benzene exposure during refuelling and commuting in a private vehicle in Perth was needed, and secondly, to make an assessment of risk attributable to these activities. Benzene source measurements were conducted in two carparks in the Central Business District (CBD), in the vicinity of the northbound and southbound lanes of the Kwinana Freeway, and at a petrol station. The 7- day arithmetic mean benzene concentrations in the carparks were 4.49 ìg m-3 and 1.23 ìg m-3. The 7-day mean benzene concentrations northbound on the Kwinana Freeway was 2.78 ìg m-3, and the mean benzene concentration southbound was 2.57 ìg m-3. Benzene emissions in the carpark and on the Kwinana Freeway were measured during vehicle idling, which is representative of vehicle speed during heavy vehicle traffic. Benzene emissions at the petrol station were monitored in the vicinity of the petrol bowser, which is representative of emissions during refuelling. The 24-hour mean benzene concentration at the petrol station bowser was 38.15 ìg m-3. The results of this research revealed that refuelling and commuting in a private vehicle are the most significant contributors to non-industrial benzene exposure in Perth, and that the contribution of these two activities in Perth is far greater than in previous published research, on the basis of the results obtained from the generalised linear model. The results of this research quantified the increase in non-industrial benzene exposure from refuelling and commuting in a private motor vehicle in a Mediterranean climate for the first time, and quantified the lifetime excess cancer risk attributable to these activities in a Mediterranean climate for the first time. The lifetime excess cancer unit risks of these two activities in a Mediterranean climate were 7.4x10-5 or 7.4 per 100000 population for commuting and 15.03 x 10-4 or 15 per 10000 for refuelling.

This master thesis evaluates the spatial variability of concentrations of PM10 on the area of towns Mladá Boleslav, Kosmonosy and small village Plazy during one month in the winter of 2013. Using a network measurements, we tried to determine whether sources of pollution are inside the city, or whether these harmful substances are transferred from the outside of the city to the area of the city. For the measurements we used a set of 9 portable laser nephelometers DustTrak (8520, TSI), which were placed on the roofs of schools. In the same time the device called beta-prachoměr (beta dust-meter) was continuously measuring concentrations of PM10, and we also monitored basic meteorological parameters (temperature, humidity, wind speed and direction). All these parameters were continuously measured at five minutes intervals. Also we did personal walks through the city, during which we measured personal exposure to PM10 concentrations. This exposure was compared with exposure of stationary monitors, and finally the differences were quantified. In Mladá Boleslav and in Kosmonosy, the same trend of concentrations of PM10 was observed at all selected locations in the city. Different trend of PM10 concentrations was observed in the village Plazy, where the peaks were higher and more frequent, especially in...

Much previous work on air pollution epidemiology has studied end-stage outcomes such as mortality or severe ill health warranting emergency admission, often based on clinical criteria prone to misclassification, and usually without accompanying study of the mediating mechanisms. Therefore this work has three specific objectives: firstly, to assess the effects of short-term exposure to particles and gases on acute coronary syndrome (ACS), by measuring the levels of cardiac troponin T (cTnT), a highly sensitive and specific marker of myocardial damage in patients admitted to hospital for chest pain of myocardial origin; secondly, to investigate the effects of short-term changes in ambient air pollution on the occurrence of transient ischaemic attacks (TIA); finally, to investigate the effects of ambient and personal exposure to air pollutants on a range of mediators or markers in a putative susceptible population. Two case-crossover studies were conducted to study the association between short-term changes in air pollutants and ischaemic cardiac events and TIA. Hospital data on admissions were analysed for actual or suspected ischaemic events and the associated cTnT levels were obtained. For the TIA project, data on 709 subjects were obtained from five TIA centres clustered around Manchester and Liverpool. In the third project a panel of 35 type 2 diabetes mellitus patients were prospectively followed fortnightly for a total of four visits. At each visit blood was collected to measure markers of inflammation, coagulation and endothelial function. In all three projects ambient air pollution data were obtained from background monitoring networks and in the third project personal exposure to PM2.5 was measured. Project 1: Of 28,622 admissions, 17.5% were ACS with myocyte necrosis (cTnT 0.03-1ng/ml) and 1004 (3.5%) were cases of myocardial infarction (cTnT ≥ 1 ng/ml). Both particulate and gaseous pollutants were associated with admission for ACS. The two largest effects per interquartile increase of exposure were observed with PM10 with ORof 1.14 (95% CI: 1.05-1.24) and with SO2, OR 1.11 (95% CI: 1.00-1.23). Associations between pollution and ACS admissions were the strongest for women, those above the age of 65 years and in the cooler season. Project 2: In the Manchester dataset, exposure to nitric oxide (NO) was associated with occurrence of TIA, while no effect was observed for Liverpool data. Subgroup analysis reveals that CO, NO and NO2 were more strongly related to the occurrence of TIA in participants above the age of 65 years and male patients. Project 3: No consistent association was observed between measured biomarkers and air pollutants using exposure data from ambient monitoring stations. In contrast, significant association between personal PM2.5 and interleukin-6 (IL-6) was observed. Similarly, personal PM2.5 had large but non-significant positive associations with high sensitivity C-reactive protein and fibrinogen. The results of this study reveal that short-term changes in particulate and gaseous pollution are related to the risk of admission for ACS as demonstrated by a specific marker hitherto not used for this purpose. It provides limited evidence for an association between changes in ambient NO concentration (which may have been a surrogate for another pollutant), and the occurrence of TIA, which had not previously been studied as an air pollution outcome, and increase in IL-6, a major pro-inflammatory marker. The IL-6 response to personal PM2.5 provides evidence in support of the link between ambient levels of particles/gases and cardiopulmonary morbidity and mortality.

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IMPACTS OF AIR POLLUTION ON OXIDATIVE DNA DAMAGE Vlasta Svecova Department of Genetic Ecotoxicology, Institute of Experimental Medicine AS CR, v.v.i. Videnska 1083, 142 20 Prague 4 Tel.: +420 241 062 669, fax.: +420 241 062 785, e-mail: svecova@biomed.cas.cz This thesis deal with impacts of air pollution on human health. The biomarkers of biologically effective dose, biomarkers of oxidative damage to DNA, lipids and proteins, were studied. We aimed at importance of individual pollutants, measured the personal exposure to these pollutants and analyzed the biomarkers of oxidative damage to macromolecules. c-PAHs (carcinogenic polycyclic aromatic hydrocarbons) bound to airborne PM2.5 (particulate matter ≤ 2.5 µm) and volatile organic compounds (benzene, toluene, ethylbenzene and m,p,o-xylenes, BTEX) were studied as ones of the biologically most important pollutants. Personal and outdoor concentrations of c-PAHs together with personal exposure to BTEX were measured. The concentrations of pollutants were correlated with biomarker levels in different seasons and localities. Bus drivers in Prague, 6-10 years old children from Teplice and Prachatice and policemen with office workers from Ostrava region were the model populations. Oxidative damage to DNA were measured by 8-oxodeoxyguanosine (8-oxodG), 15-F2t-...

abstract: Air pollution has been linked to various health problems but how different air pollutants and exposure levels contribute to those diseases remain largely unknown. Researchers have mainly relied on data from government air monitoring stations to study the health effects of air pollution exposure. The limited information provided by sparse stations has low spatial and temporal resolution, which is not able to represent the actual exposure of individuals. A tool that can accurately monitor personal exposure provides valuable data for epidemiologists to understand the relationship between air pollution and certain diseases. It also allows individuals to be aware of any ambient air quality issues and prevent air pollution exposure. To build such a tool, sensors with features of fast response, small size, long lifetime, high sensitivity, high selectivity, and multi-analyte sensing are of great importance. In order to meet these requirements, three generations of novel colorimetric sensors have been developed. The first generation is mosaic colorimetric sensors based on tiny sensor blocks and by detecting absorbance change after each air sample injection, the target analyte concentration can be measured. The second generation is a gradient-based colorimetric sensor. Lateral transport of analytes across the colorimetric sensor surface creates a color gradient that shifts along the transport direction over time, and the sensor tracks the gradient shift and converts it into analyte concentration in real-time. The third generation is gradient-based colorimetric arrays fabricated by inkjet-printing method that integrates multiple sensors on a miniaturized sensor chip. Unlike traditional colorimetric sensors, such as detection tubes and optoelectronic nose, that are typically for one-time use, the presented three generations of colorimetric sensors aim to continuously monitor multiple air pollutants and the sensor lifetime and fabrication methods have been improved over each generation. Ozone, nitrogen dioxide, formaldehyde and carbon monoxide are chosen as analytes of interest. The performance of sensors has been validated in the lab and field tests, proving the capability of the sensors to be used for personal exposure monitoring. / Dissertation/Thesis / Doctoral Dissertation Chemistry 2019

Adverse health effects from exposure to air pollution, although at present only partly understood, are a global challenge and of widespread concern. Quantifying human exposure to air pollutants is challenging, as ambient concentrations of air pollutants at potentially harmful levels are ubiquitous and subject to high spatial and temporal variability. At the same time, individuals have their very own unique activity-patterns. Hence exposure results from intertwined relationships between environmental and human systems add complexity to the assessment process. It is essential to develop a deeper understanding of individual exposure pathways and situations occurring in people’s everyday lives. This is important especially with regard to exposure and health impact assessment which provide the basis for public health advice and policy development. This thesis describes the development and application of a personal monitoring method to assess exposure to fine particulate matter in a variety of microenvironments. Tools and methods applied are tested with respect to feasibility, intrusiveness, performance and potential for future applications. The development of the method focuses on the application in everyday environments and situations in an attempt to capture as much of the total exposure as possible, across a complete set of microenvironments. Seventeen volunteers took part in the pilot study, collected data and provided feedback on methodology and tools applied. The low-cost particle counter applied showed good agreement with reference instruments when studied in two different environments. Based on the assessment of the two instruments functions to derive particle mass concentration from the original particle number counts have been defined. The application of the devices and tools received positive feedback from the volunteers. Limitations are mainly related to the non-weatherproof design of the particle counter. The collection of time-activity patterns with GPS and time-activity diaries is challenging and requires careful processing. Resulting personal exposure profiles highlight the influence of individual activities and contextual factors. Highest concentrations were measured in indoor environments where people also spent the majority of time. Differences between transport modes as well as between urban and rural areas were identified.

Population exposure to traffic pollution is a rapidly developing, multi-disciplinary scientific field. While the link between long-term exposure and respiratory issues is well-established, there are probable links to a number of more serious health effects, which are still not fully understood. In the interests of protecting human health, it is prudent that we take a cautionary approach and actively seek to reduce exposure levels, especially in the home environment where people spend a significant portion of their time. In many large cities, a substantial number of homes are situated on land immediately adjacent to busy freeways and other heavily-trafficked roads. Characterising exposures of local residents is incredibly challenging but necessary for advancing epidemiological understandings. While existing studies are plentiful, the results are mixed and generally not transferable to other urban areas due to the localised nature of the built environment and meteorological influences. This thesis aimed to employ a variety of methods to develop a holistic understanding of the influence of traffic emissions on near-highway residents' exposure in two communities of South Auckland, New Zealand, where Annual Average Daily Traffic (AADT) is as high as 122,000 vehicles. First, ultrafine particles (UFPs), nitrogen oxides (NOx), carbon monoxide (CO) and particulate matter ≤ 10 μm (PM₁₀) were continuously monitored using a series of fixed stations at different distances from the highways, over several months during the winters of 2010 and 2011. Emissions modelling output (based on traffic composition), was used within a dispersion model to compare modelled concentrations with monitored levels. In addition, community census meshblock units were mapped by level of social deprivation in order to assess potential inequities in highway emissions exposure. The second layer of local air quality investigation involved using a bicycle platform to systematically measure concentrations of UFPs, CO and PM₁₀ using the entire street-grid network throughout each community. This was done forty times - five times at four times of day (07:00, 12:00, 17:00 and 22:00), for each study area, with the aim of mapping the diurnal fluctuation of microspatial variation in concentrations. Using global positioning system (GPS) data and geographical information system (GIS) software, spatially-resolved pollutant levels were pooled by time of day and the median values mapped, providing a visualisation of the spatial extent of the influence of emissions from the highways compared to minor roads. The third layer involved using data from multiple ambient monitors, both within the local areas and around the city, to simulate fifty-four residents' personal exposure for the month of June, 2010. This required collecting timeactivity information which was carried out by door-to-door surveying. The time-activity data were transformed into microenvironment and activity codes reflecting residents movements across a typical week, which were then run through the US-EPA's Air Pollution Exposure Model (APEX). APEX is a probabilistic population exposure model for which the user sets numerous microenvironmental parameters such as Air Exchange Rates (AERs) and infiltration factors, which are used in combination with air pollutant concentrations, meteorological, and geospatial data, to calculate individuals' exposures. Simulated exposure outputs were grouped by residents' occupations and their home addresses were artificially placed at varying distances from the highways. The effects of residential proximity to the highway, occupation, work destination and commute distance were explored using a Generalised Linear Model (GLM). Surveyed residents were also asked a series of Likert-type, ordered response questions relating to their perceptions and understandings of the potential impacts of living near a significant emissions source. Their response scores were explored as a function of proximity to the highway using multivariate linear regression. This formed the final layer of this investigation into air quality throughout these South Auckland communities of Otahuhu and Mangere Bridge. Results show that concentrations of primary traffic pollutants (UFPs, NOx, CO) are elevated by 41 - 64% within the roadside corridor compared to setback distances approximately 150 m away and that the spatial extent of UFPs can reach up to 650 m downwind early in the morning and late in the evening. Further, social deprivation mapping revealed that 100% of all census meshblocks within 150 m either side of both highways are at the extreme end of the deprivation index (NZDep levels 8 - 10). Simulations for residents dispersed across the community of Otahuhu estimated daily NOx and CO exposure would increase by 32 and 37% (p<0.001) if they lived immediately downwind of the highway. If they were to shift 100 m further downwind, daily exposure would decline by 56 - 70% (p<0.001). The difference in individuals' exposure levels by occupation varied across the same distance by a factor of eight (p<0.05), with unemployed or retired persons the most exposed due to having more free time to spend outdoors at home (recreation, gardening, etc.). Those working in ventilated offices were the least exposed, even though ambient concentrations - likely due to a strong urban street canyon effect - were higher than the nearest highway monitor (5 m downwind) by 25 - 30% for NOx and CO, respectively. Inverse linear relationships were identified for distance from highway and measures of concern for health impacts, as well as for noise (p<0.05). Positive linear relationships were identified for distance from highway and ratings of both outdoor and indoor air quality (p<0.05). Measures of level of income had no conclusive statistically significant effect on perceptions (p>0.05). The main findings within this thesis demonstrate that those living within the highway corridor are disproportionately exposed to elevated long-term average concentrations of toxic air pollutants which may impact on physical health. While the socioeconomic characteristics could also heighten susceptibility to potential health impacts in these areas, certain activity patterns can help mitigate exposure. This thesis has also shown that there may be quantifiable psychological benefits of a separation buffer of at least 100 m alongside major highways. These results enhance a very limited knowledge base on the impacts of near-roadway pollution in New Zealand. Furthermore, the results lend additional support to the international literature which is working to reduce residential exposures and population exposure disparities through better policies and improved environmental planning. Where possible, the placement of sensitive population groups within highway corridors, e.g. retirement homes, social housing complexes, schools and childcare centres, should be avoided.

Für die Luftqualitätsbewertung in Städten sind Informationen zur raumzeitlichen Variabilität luftgetragener Feinstäube auf kleiner Skala von wichtiger Bedeutung. Standardisierte Messverfahren, zur Bestimmung von Partikelkonzentrationen, sind mit hohem Aufwand verbunden, weshalb dichte Messnetze fehlen. Partikelausbreitungsmodelle sind kompliziert in der Anwendung und/oder benötigen hohe Computerrechenleistung. Infolgedessen gibt es bezüglich örtlicher Partikelkonzentrationen große Informationslücken. Diese Arbeit untersucht die mikroskalige Variabilität von Aerosolen in Raum und Zeit mit unterschiedlichen Methoden. Es wurden Erhebungen mit mobilen Sensoren und eine Passantenbefragung durchgeführt. Weiterhin wurden in dieser Arbeit die physikalischen Partikeltransportmodelle ENVI-met und Austal2000 in ihrer Leistung bewertet und in angewandten Studien eingesetzt. Weiterhin wurde ein neuronales Netzwerk zur Vorhersage von Partikelkonzentrationen entwickelt. Die Untersuchungen erfolgten in den Städten Aachen und Münster. Es konnten unerwartete Verteilungsmuster hinsichtlich der Massekonzentration von Partikeln beobachtet werden. In einem innerstädtischen Park wurden diffuse Partikelquellen identifiziert, mit einem deutlichen Hinweis darauf, dass feuchtgelagerte Wegedecken einen maßgeblichen Anteil an lokalen Partikelimmissionen hatten. Weiterhin wurde Straßenverkehr als wichtiger Beitrag zum städtischen Aerosol identifiziert. Passanten, die verschiedenen Partikelkonzentrationen ausgesetzt waren, konnten diese perzeptiv nicht unterscheiden. Simulationsergebnisse von Austal2000 und ENVI-met wiesen Unterschätzungen im Vergleich zu Messwerten auf. Das entwickelte neuronale Netzwerk prognostizierte Partikelkonzentrationen teilweise mit hoher Genauigkeit. Das große Potenzial von neuronalen Netzen für die Vorhersage von Partikelkonzentrationen in räumlicher und zeitlicher Ausdehnung, auch für den Bereich der Luftqualitätsüberwachung, wurde aufgezeigt. / Knowledge about the micro-scale variability of airborne particles is a crucial criterion for air quality assessment within complex terrains such as urban areas. Due to the significant costs and time consumption related to the work required for standardized measurements of particle concentrations, dense monitoring networks are regularly missing. Models that simulate the transmission of particles are often difficult to use and/or computationally expensive. As a result, information regarding on-site particle concentrations at small scales is still limited. This thesis explores the micro-scale variability of aerosol concentrations in space and time using different methods. Experimental fieldwork, including measurements with mobile sensor equipment alongside a survey, and modeling approaches were conducted. Applied simulation studies, a performance assessment of two popular particle dispersion models, namely Austal2000 and ENVI-met, as well as the development of an ANN model are presented. The cities of Aachen and Münster were chosen as case studies for this research. Unexpected patterns of particle mass concentrations could be observed, including the identification of diffuse particle sources inside a park area with strong evidence that unpaved surfaces contributed to local aerosol concentration. In addition, vehicle traffic was proved to be a major contributor of particles, particularly close to traffic lanes. Results of the survey reveal that people were not able to distinguish between different aerosol concentration levels. Austal2000 and ENVI-met turned out to have room for improvement in terms of the reproduction of observed particle concentration levels, with both models having a tendency toward underestimation. The newly developed ANN model was confirmed to be a fairly accurate tool for predicting aerosol concentrations in both space and time, and demonstrates the principal ability of the approach also in the domain of air quality monitoring.