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Traffic-related air pollution (TRAP), including particulate matter (PM) in respirable coarse and fine size fractions (PM10 and PM2.5), is known to have exposure effects on human health and environment. Real-time PM10 and PM2.5 concentrations were collected from the study locations in Bangkok, Thailand, using TSI AM510 particle counters. Temperature and % relative humidity (%RH) were also collected. Data were compared to data from the closest station of the Pollution Control Department (PCD), Thailand. Real-time mean concentration varied from 86 to 1107 µg/m3(PM10) and varied from 25 to 664 µg/m3(PM2.5). In addition, real-time mean PM10 (223.1 µg/m3) was nearly four times greater than that measured by the PCD station, 60 µg/m3. Temperature and %RH from real-time air monitoring and PCD station were comparable. In each study location (five locations, two in morning and afternoon/evening), there were significant positive correlations between PM10 and PM2.5 concentrations and significant negative correlations between temperature and RH%. Results suggested that outdoor TRAP via measured real-time PM concentrations were more realistic exposure concentration estimates among street vendors as related to respiratory and other symptoms than data obtained from PCD station. Nevertheless, PM10 as measured by the PCD station might be a reasonable surrogate for estimated outdoor PM2.5 exposure. [ABSTRACT FROM PUBLISHER]

Abstract: In-vehicle air quality (IVAQ) can be a major health concern due to factors such as urban sprawl and increased commuting time spent by individuals in vehicles. Few studies, particularly in the U.S., have considered in-vehicle toxic air contaminants, and none to date collected/analyzed field data in multiple communities across multiple climate zones. This study presents analyses of field data collected during the RIOPA Study from participating non-smoking adults for communities in Los Angeles County, CA, Elizabeth, NJ and Houston, TX. A significant difference (p < 0.001) in in-vehicle formaldehyde concentrations was observed, with the median concentration of in-vehicle formaldehyde in the CA communities about twice as high as in the NJ and TX communities. The highest median concentration of in-vehicle acetaldehyde was observed among the TX participants, over 40% higher than the overall study median. Given small sample sizes, the community (state) differences may be driven independently by differences in individual vehicle conditions and driving habits. Positive correlations were found between average community outdoor relative humidity in CA and NJ and in-vehicle formaldehyde and acetaldehyde concentrations. The amount of time car windows were reported as closed was inversely correlated with in-vehicle formaldehyde across study locations, and for in-vehicle acetaldehyde in CA and TX. Average wind speed and varying sky conditions also had suggested associations to in-vehicle formaldehyde and acetaldehyde. In CA and TX, 88% (7/8) of participants with a diagnosis of bronchitis reported at study baseline had in-vehicle formaldehyde concentrations greater than the overall study median. Every participant with diagnoses of both asthma and bronchitis (n = 3) reported at study baseline had in-vehicle formaldehyde and acetaldehyde concentrations above the overall study median; one participant in TX with two seasonal in-vehicle samplings had in-vehicle concentrations > 75th percentile. IVAQ during commuting may vary based on human behavior and meteorological factors. Additional studies are needed to further characterize ways to help reduce in-vehicle aldehyde exposures, especially for people with existing chronic respiratory illnesses who could experience symptom exacerbations upon such exposures. [Copyright &y& Elsevier]

Abstract: We can control asthma through proper clinical and environmental management and education. The U.S. population is growing, urbanizing and aging; seniors of low-to-middle income families are working and living longer. We conducted community-based participatory research in Visalia, Tulare County, California with a prospective, cross-sectional repeated measures design and quantitative and qualitative process; home environment and health-related outcomes data were collected. In this paper, we presented results of the air quality sampling—pollen, carbon dioxide (CO2) and particulate matter (PM) outdoors away from most major sources (agricultural fields, large pollinating trees, etc)—at a community central site close to a mobile line source and participant homes in the cooling season, July, 2009. Weather was hot and dry with light winds; diurnal variation ranged between 65–107°F (18–42°C) and 12–76% relative humidity at the study’s central site. Co-located active (reference) and passive (PAAS) samplers were used for pollen; passive monitoring for CO2 (Telaire 7001) and active sampling for PM were conducted. Overall, we observed spatial variability in CO2, fine PM (PM2.5), and pollen counts. Weekday and study week average CO2 and PM2.5 concentrations were higher near study homes compared to central site sampling points, but peak measures and overnight/pre-dawn time period averages were elevated at the central site. Pollen counts were typically lower at homes—even if grass, trees, flowers or potted plants were present—compared to the central site closer to and generally downwind from commercial agricultural tree production. Data are new; the nine-county San Joaquin Valley has one pollen count station in the national network, and two of four government outdoor air monitoring stations in the county are in national parks. We suggest—given poor air quality in large part due to PM—adding routine pollen counts to regional/state agency air monitoring sites and more CO2 and PM monitoring. [Copyright &y& Elsevier]

Objective. Research on air quality in and around schools, and the associated vulnerability of school-age children, is limited in less developed countries (LDCs), particularly Africa. The main objective of this study was to conduct an initial assessment of sources of air pollution in and around schools as a surrogate for air quality and report adverse health effects among students at selected secondary schools in urban Ibadan, Nigeria. Methods. The study was a descriptive cross-sectional survey involving eight secondary schools selected purposively, defined with eight acronyms (listed alphabetically): ABHS, AGS, BOHS, CDSS, IGS, LC, MGS, and OAHS. We used pre-tested, self-administered questionnaires, observational checklists to assess certain environmental health indicators, and interviews. The questionnaire was divided into five sections including environmental and health conditions. A total of 400 students from senior secondary classes, 50 from each school, were selected through stratified random sampling. Results. The school's location, especially if close to high traffic roadways, contributed to reported perceived poor air quality of school environments. The majority of students believed air pollution sources in the school environment were mainly refuse burning and car emissions from nearby roadways. Cough and asthma were the most frequently reported adverse health outcomes. The highest prevalence of reported recent asthma episodes (symptoms) were recorded at BOHS (84%) and at CDSS (62%); furthermore, at ABHS it was nearly 1-in-2 students and at OAHS about 1-in-5 students. BOHS and OAHS each reported over 10% for prevalence of bronchitis. Conclusions. Proximity of study schools to certain sources and activities such as refuse burning and major roadways seemed to present substantial risk factors for reported respiratory morbidity among secondary students in urban Ibadan, Nigeria. Future research should quantify source emissions and exposure and further characterize frequency and severity of respiratory symptoms, among other parameters, at schools in Nigeria and other sprawling urban areas of Africa. [ABSTRACT FROM AUTHOR]

The Relationship of Indoor, Outdoor and Personal Air (RIOPA) Study was undertaken to evaluate the contribution of outdoor sources of air toxics, as defined in the 1990 Clean Air Act Amendments, to indoor concentrations and personal exposures. The concentrations of 18 volatile organic compounds (VOCs), 17 carbonyl compounds, and fine particulate matter mass (PM2.5) were measured using 48-h outdoor, indoor and personal air samples collected simultaneously. PM2.5 mass, as well as several component species (elemental carbon, organic carbon, polyaromatic hydrocarbons and elemental analysis) were also measured; only PM2.5 mass is reported here. Questionnaires were administered to characterize homes, neighborhoods and personal activities that might affect exposures. The air exchange rate was also measured in each home. Homes in close proximity (<0.5?km) to sources of air toxics were preferentially (2:1) selected for sampling. Approximately 100 non-smoking households in each of Elizabeth, NJ, Houston, TX, and Los Angeles, CA were sampled (100, 105, and 105 respectively) with second visits performed at 84, 93, and 81 homes in each city, respectively. VOC samples were collected at all homes, carbonyls at 90%and PM2.5 at 60%of the homes. Personal samples were collected from nonsmoking adults and a portion of children living in the target homes. This manuscript provides the RIOPA study design and quality control and assurance data. The results from the RIOPA study can potentially provide information on the influence of ambient sources on indoor air concentrations and exposure for many air toxics and will furnish an opportunity to evaluate exposure models for these compounds.Journal of Exposure Analysis and Environmental Epidemiology (2005) 15, 123-137. doi:10.1038/sj.jea.7500379 Published online 23 June 2004 [ABSTRACT FROM AUTHOR]

Ambient concentrations and the elemental composition of particles less than 2.5 μm in diameter (PM2.5), as well as carbon monoxide (CO) concentrations, were measured at ground-level in three Guatemalan cities in summer 1997: Guatemala City, Quetzaltenango, and Antigua. This pilot study also included quantitative and qualitative characterizations of microenvironment conditions, e.g., local meteorology, reported elsewhere. The nondestructive X-ray fluorescence elemental analysis (XRF) of Teflon filters was conducted. The highest integrated average PM2.5 concentrations in an area (zona) of Guatemala City and Quetzaltenango were 150 μg m−3 (zona 12) and 120 μg m−3 (zona 2), respectively. The reported integrated average PM2.5 concentration for Antigua was 5 μg m−3. The highest observed half-hour and monitoring period average CO concentrations in Guatemala City were 10.9 ppm (zona 8) and 7.2 ppm (zonas 8 and 10), respectively. The average monitoring period CO concentration in Antigua was 2.6 ppm. Lead and bromine concentrations were negligible, indicative of the transition to unleaded fuel use in cars and motorcycles. The XRF results suggested sources of air pollution in Guatemala, where relative rankings varied by city and by zonas within each city, were fossil fuel combustion emitting hydrocarbons, combustion of sulfurous conventional fuels, soil/roadway dust, farm/agricultural dust, and vehicles (evaporation of gas, parts'' wear). [Copyright &y& Elsevier]

Examines the polycyclic aromatic hydrocarbons (PAH) in the indoor and outdoor air of cities in the U.S. Effects of particulate matter on indoor air quality; Air exchange rates in homes; Occurrence of PAH in urban atmospheric environments.