Abstract  INTRODUCTION: Research on the deposition of mainstream smoke particulate in the respiratory tract of smokers is needed to understand how exposure may vary based on cigarette menthol content.

METHODS: We conducted a nine-participant crossover study in which smokers were randomly assigned to cigarettes differing primarily in menthol content. Participants smoked the test cigarettes ad libitum for one week, provided spot urine samples, and then smoked four test cigarettes in a laboratory session; this was repeated for the other test cigarette in week two. Fine and ultrafine particulate matter in exhaled breath were characterized, and smoking behavior was monitored. Participant-specific mainstream smoke, generated using each participant's topography data, was characterized. During home smoking, participants collected their spent test cigarette butts for estimates of mouth-level exposures (MLE) to mainstream nicotine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK).

RESULTS: Participant-specific mainstream smoke NNK was higher (39%) and daily MLE to NNK was also higher (52%) when participants smoked the menthol cigarette. Nicotine was not significantly different. Participants retained more ultrafine particulate (43%) and fine particulate benzo(a)pyrene (43%) when smoking the menthol cigarette. There were no significant differences in the levels of urinary biomarkers for nicotine, NNK, or pyrene.

CONCLUSION: This study demonstrates the use of noninvasive real-time techniques to measure exposure differences between cigarettes differing primarily in menthol content. Differences between NNK exposure, ultrafine particle and benzo(a)pyrene deposition, and smoking behavior were observed. Additional research using these techniques with cigarettes that differ only in menthol content is required to unequivocally attribute the exposure differences to presence or absence of menthol.

Abstract  Background: Telomere shortening in blood leukocytes has been associated with increased morbidity and death from cardiovascular disease and cancer, but determinants of shortened telomeres, a molecular feature of biological aging, are still largely unidentified. Traffic pollution has been linked with both cardiovascular and cancer risks, particularly in older subjects. Whether exposure to traffic pollution is associated with telomere shortening has never been evaluated. Methods: We measured leukocyte telomere length (LTL) by real-time PCR in blood DNA from 77 traffic officers exposed to high levels of traffic pollutants and 57 office workers (referents). Airborne benzene and toluene, as tracers for traffic exposure, were measured using personal passive samplers and gas-chromatography/ flame-ionization detector analysis. We used covariate-adjusted multivariable models to test the effects of the exposure on LTL and obtain adjusted LTL means and 95% Confidence Intervals (CIs). Results: Adjusted mean LTL was 1.10 ( 95% CI 1.04-1.16) in traffic officers and 1.27 in referents ( 95% CI 1.20-1.35) [p < 0.001]. LTL decreased in association with age in both traffic officers (p = 0.01) and referents ( p = 0.001), but traffic officers had shorter LTL within each age category. Among traffic officers, adjusted mean relative LTL was shorter in individuals working in high (n = 45, LTL = 1.02, 95% CI 0.96-1.09) compared to low traffic intensity ( n = 32, LTL = 1.22, 95% CI 1.13-1.31) [ p < 0.001]. In the entire study population, LTL decreased with increasing levels of personal exposure to benzene ( p = 0.004) and toluene ( p = 0.008). Conclusion: Our results indicate that leukocyte telomere length is shortened in subjects exposed to traffic pollution, suggesting evidence of early biological aging and disease risk.

Abstract  In this study, the concentrations of five volatile organic compounds (VOCs), including BTEX and methyl tertiary-butyl ether (MTBE), were investigated in five different traffic tunnels (including Liangshan, Yueguangshan, Zoying, Guogang and Zhongliao tunnels) in southern Taiwan. Results showed that Guogang Tunnel was the most polluted with the highest average levels of both MTBE and BTEX while ethylbenzene had the lowest levels. The range of measured concentration of toluene in Liangshan, Yueguangshan, Zoying, Guogang and Zhongliao tunnels were from 5.6 to 6.2 (mean = 1.6), from 0.0 to 62.3 (mean = 17.6), from 2.7 to 26.7 (mean = 13.1), from 15.2 to 125.5 (mean = 57.5), and from 43.7 to 197.1 (mean = 115.8) mu g/m(3), respectively. In Guogang Tunnel, the average MTBE-BTEX ratios at two peak rush periods were (5.0:1, 5:3, 4:1, 0:1, 5:1.1) and (5.7:1, 3:3, 2:1, 0:1, 4:1.1). From morning till night, the ratios at different sampling periods in the five different tunnels suggest the existence of both different traffic flow and variations in traffic fleet type in different tunnels. T/B ratio ranged from 0 to 2.3, from 0 to 1.9, from 0.6 to 2.5, from 0.9 to 2.6 and from 0 to 10.5 in Liangshan, Yueguangshan, Zoying, Guogang and Zhongliao tunnels, respectively. We also observed a wide range of (m+p+o)-xylenes/ethylbenzene (Sigma X/E) or m,p-X/E ratio in all five tunnels. The m,p-xylene/ethylbenzene ratio ranged from 2.2 to 5.7, from 1.4 to 3.3, from 2.0 to 7.7, from 1.4 to 1.5 and from 5.5 to 8.1 in Liangshan, Yueguangshan, Zoying, Guogang and Zhongliao Tunnels, respectively. Notably, those high Sigma X/E ratios in all tunnels reflect a fresh air parcel in the tunnels due to the enclosed/half-enclosed environment. Nevertheless, it is important that the characteristics of X/E in different traffic tunnels are explored.

Abstract  The present work presents a measurement uncertainty evaluation according to Guide to the Expression of Uncertainty in Measurement (GUM) of the concentration of the cations K+ and Li+ and anions NO3-2 and SO4-2 in fine airborne particulate matter, refers to particles less than 2.5 mu m in diameter (PM2.5), as measured by ion chromatography (US-EPA 300 method). The GUM method is not typically used to report uncertainty. In general, the analytical results only report the measurement's standard deviation under repetition as an uncertainty; thus, not all sources of uncertainty are considered. In this work, the major sources of uncertainty regarding the measurements were identified as contributions to linear least square regression lines, repeatability, precision, and trueness. The expanded uncertainty was approximately 20% for anions and cations. The largest contribution to uncertainty was found to be repeatability.

Abstract  In a time series studies, air pollution was associated with specific cardiovascular mortality, but little is known about the short-term nitrogen dioxide (NO2) effects on acute heart attack risk. The objective of the study was to estimate association between NO2 exposure and emergency hospital admission for myocardial infarction and unstable angina pectoris in Kaunas within 2005-2006 periods. Associations were assessed using the case-crossover method and multivariate logistic regression. Mean daily levels of NO2 were related to the daily number of hospital admissions for heart attack. The relative risk for increase of heart attack admissions, evaluated at NO2 tertiles of day of admission and 2 days prior to the data of admissions were as follows: 1; 2.22, 95% CI 1.32-3.76; 2.84, 95% CI 1.70-4.77 and 1; 1.70, 95% CI 1.03-2.82; 2.10, 95% CI 1.27-3.45. The hospital admission odds ratios for each 10 mu g/m(3) increase in NO2 level was associated with a risk of heart attack admissions of 28% (OR=1.28, 95% Cl 1.11-1.48; p<0.001). These findings suggest that higher ambient NO2 levels might bee associated with increase of heart attack risk.

Abstract  Environment tobacco smoke (ETS) is an important source of anthropogenic pollution in indoor environments. This research reports an environmental chamber study of pollutants released from ETS generated by smoking cigarettes in the chamber. Six cigarettes samples sold in Hong Kong and China were characterized. Gaseous pollutants: carbon monoxide (CO), sulphur dioxide (SO2), nitric oxide (NO), nitrogen dioxide (NO2), methane (CH4), non-methane hydrocarbon (NMHC), carbonyls and volatile organic compounds (VOCs); and particulate matter (PM), including organic carbon (OC), elemental carbon (EC) and total carbon (TC), were determined using online and offline analytical methods during smoking and post-smoking periods. Acetaldehyde, acetone and formaldehyde were the three most abundant carbonyls. A total of 18 aromatic and chlorinated VOCs were quantified. Among these, benzene and toluene were the two most abundant VOCs. OC was more dominant (> 93% of TC) than EC. The amounts of tar and nicotine in the cigarettes could have a direct correlation with the PM emitted. Menthol, an additive in cigarettes, could also contribute to the ETS pollutants. The indoor ETS could be removed by a higher air exchange rate, which would also minimize secondary VOC formation.

Abstract  In China, dust samplers were originally designed to collect 'total dust' for a short term during production, which is different from the widely adopted sampling strategy for dust. With the aim to provide the conversion factor from Chinese total dust to US and German respirable dust and to look at the influences on conversion factors from environment, production, and instruments, a comparative field study on the dust concentration measurements by different sampling methods was carried out in the same Chinese industries as in the 1989-1990 study and in some other factories. A supplemental experiment was also conducted in a wind tunnel. Dust concentration was measured with a parallel sampling strategy by using the following samplers: 10-mm nylon cyclone for US respirable dust (AR), FSP-Berufsgenossenschaftliches Institut für Arbeitssicherheit (BIA) cyclone for German respirable dust (GR), and samplers for Chinese total dust (CT). Totally, 1434 samples were collected (269 AR, 198 GR, and 967 CT), from which 429 matched sample pairs (249 pairs of AR/CT, 180 GR/CT) were available to calculate conversion ratios. Industry- and job-based conversion factors are presented in this study. The conversion factor of AR/CT was 0.38 for tungsten mines, 0.19 for copper/iron mines, 0.65 for tin mines, and 0.20 for pottery industry, while the factor of GR/CT was 0.69 for tungsten, 0.37 for copper/iron, and 0.52 for pottery. In the job category, AR/CT factors varied from 0.16 to 0.96 and GR/CT from 0.12 to 0.72. For the industries studied in 1988-1989, the AR/CT and GR/CT factors were 0.29 and 0.45, respectively. Both factors were definitely influenced by production, CT dust concentration, sample gain, and variation of dust concentration. Moreover, the respirable dust concentration by FSP-BIA was significantly higher than that by 10-mm cyclones, 63.27-73.10% more as showed also by the wind tunnel experiment. Meanwhile, the GR/CT ratio was significantly larger than the AR/CT in every industry or job with only few exceptions. The GR/CT estimates should be considered as independent ones. Following these results, there is a need to use 'ideal samplers' (consistent with the internationally accepted respirable fraction) in practice and to assess the existent samplers in order to homogenize the exposure data situation.

Abstract  Ozonolysis is a major tropospheric removal mechanism for unsaturated hydrocarbons and proceeds via "Criegee intermediates"--carbonyl oxides--that play a key role in tropospheric oxidation models. However, until recently no gas-phase Criegee intermediate had been observed, and indirect determinations of their reaction kinetics gave derived rate coefficients spanning orders of magnitude. Here, we report direct photoionization mass spectrometric detection of formaldehyde oxide (CH(2)OO) as a product of the reaction of CH(2)I with O(2). This reaction enabled direct laboratory determinations of CH(2)OO kinetics. Upper limits were extracted for reaction rate coefficients with NO and H(2)O. The CH(2)OO reactions with SO(2) and NO(2) proved unexpectedly rapid and imply a substantially greater role of carbonyl oxides in models of tropospheric sulfate and nitrate chemistry than previously assumed.

Abstract  From literature and wind tunnel studies it had already been concluded that noise barriers might make a significant contribution to improving air quality. Within the Dutch Air Quality Innovation Programme (IPL) several trials have been conducted at a test site along a highway to assess the impact of noise barriers on air quality along arterial roads. In 2007 IPL did organise a competition challenging companies to come up with innovative barrier designs having an additional impact on air quality compared with conventional barriers. M+P consulting engineers was commissioned to measure the impact of standard and optimised barriers on concentrations of NO2, NOx, PM10 and PM2.5 behind the barrier. In five monitoring sessions each lasting around three months, the performance of nine different barriers was investigated. The measurements were done at thirteen different positions. From the results it became clear that noise barriers reduce concentrations of nitrogen oxides and airborne particulates along motorways significantly. For example, effects of 20% for NOx were found at 10 m behind the reference barrier. The measurements show that the barrier height is a relevant parameter for the effect of the barrier. A 7m-barrier shows considerably higher reductions compared to the 4m-barrier. From the results it is also clear that the measured effects of the innovative barriers were consistently lower than for the "reference barrier". It should be kept in mind that because of the major uncertainties involved, in many cases the effects statistically do not differ significantly. It is unknown why the reference barrier performs somewhat better than the other 4-meter-high innovative barriers.

Abstract  INTRODUCTION: The Aphekom project aimed to provide new, clear, and meaningful information on the health effects of air pollution in Europe. Among others, it assessed the health and monetary benefits of reducing short and long-term exposure to particulate matter (PM) and ozone in 25 European cities.

METHOD: Health impact assessments were performed using routine health and air quality data, and a common methodology. Two scenarios were considered: a decrease of the air pollutant levels by a fixed amount and a decrease to the World Health Organization (WHO) air quality guidelines. Results were economically valued by using a willingness to pay approach for mortality and a cost of illness approach for morbidity.

RESULTS: In the 25 cities, the largest health burden was attributable to the impacts of chronic exposure to PM2.5. Complying with the WHO guideline of 10 μg/m(3) in annual mean would add up to 22 months of life expectancy at age 30, depending on the city, corresponding to a total of 19,000 deaths delayed. The associated monetary gain would total some €31 billion annually, including savings on health expenditures, absenteeism and intangible costs such as well-being, life expectancy and quality of life.

CONCLUSION: European citizens are still exposed to concentrations exceeding the WHO recommendations. Aphekom provided robust estimates confirming that reducing urban air pollution would result in significant health and monetary gains in Europe. This work is particularly relevant now when the current EU legislation is being revised for an update in 2013.

Abstract  BACKGROUND: Emergency department (ED) visit and hospital admissions (HA) data have been an indispensible resource for assessing acute morbidity impacts of air pollution. ED visits and HAs are types of health care visits with similarities, but also potentially important differences. Little previous information is available regarding the impact of health care visit type on observed acute air pollution-health associations from studies conducted for the same location, time period, outcome definitions and model specifications.

METHODS: As part of a broader study of air pollution and health in St. Louis, individual-level ED and HA data were obtained for a 6.5 year period for acute care hospitals in the eight Missouri counties of the St. Louis metropolitan area. Patient demographic characteristics and diagnostic code distributions were compared for four visit types including ED visits, HAs, HAs that came through the ED, and non-elective HAs. Time-series analyses of the relationship between daily ambient ozone and PM₂.₅ and selected cardiorespiratory outcomes were conducted for each visit type.

RESULTS: Our results indicate that, compared with ED patients, HA patients tended to be older, had evidence of greater severity for some outcomes, and had a different mix of specific outcomes. Consideration of 'HA through ED' appeared to more effectively select acute visits than consideration of 'non-elective HA'. While outcomes with the strongest observed temporal associations with air pollutants tended to show strong associations for all visit types, we found some differences in observed associations for ED visits and HAs. For example, risk ratios for the respiratory disease-ozone association were 1.020 for ED visits and 1.004 for 'HA through ED'; risk ratios for the asthma/wheeze-ozone association were 1.069 for ED visits and 1.106 for 'HA through ED'. Several factors (e.g. age) were identified that may be responsible, in part, for the differences in observed associations.

CONCLUSIONS: Demographic and diagnostic differences between visit types may lead to preference for one visit type over another for some questions and populations. The strengths of observed associations with air pollutants sometimes varied between different health care visit types, but the relative strengths of association generally were specific to the pollutant-outcome combination.

Abstract  BACKGROUND: Asthma is a chronic inflammatory disease characterized by airways hyperresponsiveness (AHR), reversible airflow obstruction, airway remodeling, and episodic exacerbations caused by air pollutants, such as particulate matter (PM; PM <2.5 μm in diameter [PM(2.5)]) and ozone (O(3)). Spleen tyrosine kinase (Syk), an immunoregulatory kinase, has been implicated in the pathogenesis of asthma.

OBJECTIVE: We sought to evaluate the effect of Syk inhibition on AHR in a chronic mouse model of allergic airways inflammation and pollutant exposure.

METHODS: We used a 12-week chronic ovalbumin (OVA) sensitization and challenge mouse model of airways inflammation followed by exposure to PM(2.5) plus O(3). Respiratory mechanics and methacholine (MCh) responsiveness were assessed by using the flexiVent system. The Syk inhibitor NVP-QAB-205 was nebulized intratracheally by using a treatment-based protocol 15 minutes before assessment of MCh responsiveness.

RESULTS: Syk expression increased significantly in the airway epithelia of OVA-sensitized and OVA-challenged (OVA/OVA) mice compared with OVA-sensitized but PBS-challenged (OVA/PBS) control mice. OVA/OVA mice exhibited AHR to MCh, which was attenuated by a single administration of NVP-QAB-205 (0.3 and 3 mg/kg). PM(2.5) plus O(3) significantly augmented AHR to MCh in the OVA/OVA mice, which was abrogated by NVP-QAB-205. Total inflammatory cell counts were significantly higher in the bronchoalveolar lavage fluid from OVA/OVA than OVA/PBS mice and were unaffected by PM(2.5) plus O(3) or NVP-QAB-205.

CONCLUSION: NVP-QAB-205 reduced AHR and the enhanced response to PM(2.5) plus O(3) to normal levels in an established model of chronic allergic airways inflammation, suggesting that Syk inhibitors have promise as a therapy for asthma.

Abstract  Exposure to high levels of air pollution during the pregnancy is associated with increased probability of preterm birth (PTB), a major cause of infant morbidity and mortality. New statistical methodology is required to specifically determine when a particular pollutant impacts the PTB outcome, to determine the role of different pollutants, and to characterize the spatial variability in these results. We develop a new Bayesian spatial model for PTB which identifies susceptible windows throughout the pregnancy jointly for multiple pollutants (PM(2.5) , ozone) while allowing these windows to vary continuously across space and time. We geo-code vital record birth data from Texas (2002-2004) and link them with standard pollution monitoring data and a newly introduced EPA product of calibrated air pollution model output. We apply the fully spatial model to a region of 13 counties in eastern Texas consisting of highly urban as well as rural areas. Our results indicate significant signal in the first two trimesters of pregnancy with different pollutants leading to different critical windows. Introducing the spatial aspect uncovers critical windows previously unidentified when space is ignored. A proper inference procedure is introduced to correctly analyze these windows.

Abstract  A novel active personal nanoparticle sampler (PENS), which enables the collection of both respirable particulate mass (RPM) and nanoparticles (NPs) simultaneously, was developed to meet the critical demand for personal sampling of engineered nanomaterials (ENMs) in workplaces. The PENS consists of a respirable cyclone and a micro-orifice impactor with the cutoff aerodynamic diameter (d(pa50)) of 4 μm and 100 nm, respectively. The micro-orifice impactor has a fixed micro-orifice plate (137 nozzles of 55 μm in the inner diameter) and a rotating, silicone oil-coated Teflon filter substrate at 1 rpm to achieve a uniform particle deposition and avoid solid particle bounce. A final filter is used after the impactor to collect the NPs. Calibration results show that the d(pa50) of the respirable cyclone and the micro-orifice impactor are 3.92 ± 0.22 μm and 101.4 ± 0.1 nm, respectively. The d(pa50) at the loaded micro-Al(2)O(3) mass of 0.36-3.18 mg is shifted to 102.9-101.2 nm, respectively, while it is shifted to 98.9-97.8 nm at the loaded nano-TiO(2) mass of 0.92-1.78 mg, respectively. That is, the shift of d(pa50) due to solid particle loading is small if the PENS is not overloaded. Both NPs and RPM concentrations were found to agree well with those of the IOSH respirable cyclone and MOUDI. By using the present PENS, the collected samples can be further analyzed for chemical species concentrations besides gravimetric analysis to determine the actual exposure concentrations of ENMs in both RPM and NPs fractions in workplaces, which are often influenced by the background or incident pollution sources.

Abstract  SO2 in central China was measured in situ from an aircraft and remotely using the Ozone Monitoring Instrument (OMI) from the Aura satellite; results were used to develop a numerical tool for evaluating the tropospheric sulfur budget - sources, sinks, transformation and transport. In April 2008, measured ambient SO2 concentrations decreased from similar to 7 ppbv near the surface to similar to 1 ppbv at 1800 m altitude (an effective scale height of similar to 800 m), but distinct SO2 plumes were observed between 1800 and 4500 m, the aircraft's ceiling. These free tropospheric plumes play a major role in the export of SO2 and in the accuracy of OMI retrievals. The mean SO2 column contents from aircraft measurements (0.73 DU, Dobson Units) and operational OMI SO2 products (0.63 +/- 0.26 DU) were close. The OMI retrievals were well correlated with in situ measurements (r = 0.84), but showed low bias (slope = 0.54). A new OMI retrieval algorithm was tested and showed improved agreement and bias (r = 0.87, slope = 0.86). The Community Multiscale Air Quality (CMAQ) model was used to simulate sulfur chemistry, exhibiting reasonable agreement (r = 0.62, slope = 1.33) with in situ SO2 columns. The mean CMAQ SO2 loading over central and eastern China was 54 kT, similar to 30% more than the estimate from OMI SO2 products, 42 kT. These numerical simulations, constrained by observations, indicate that similar to 50% (35 to 61%) of the anthropogenic sulfur emissions were transported downwind, and the overall lifetime of tropospheric SO2 was 38 +/- 7 h.

Abstract  Since the majority of schools are housed in buildings dating from the 1960s and 1970s, a comprehensive construction and renovation program of school buildings has been carried out to improve the educational conditions in Korea. However, classrooms and computer rooms, with pressed wood desks, chairs and furnishings, as well as construction materials, might have negative effects on the indoor air quality. Furthermore, most schools have naturally ventilated classrooms. The purpose of this study was to characterize the concentrations of different indoor air pollutants within Korean schools and to compare their indoor levels within schools according to the age of school buildings. Indoor and outdoor air samples of carbon monoxide (CO), carbon dioxide (CO(2)), particulate matter (PM(10)), total microbial count (TBC), total volatile organic compounds (TVOCs) and formaldehyde (HCHO) were obtained during summer, autumn and winter from three sites; a classroom, a laboratory and a computer classroom at 55 different schools. The selection of the schools was based on the number of years since the schools had been constructed. The problems causing indoor air pollution at the schools were chemicals emitted by building materials or furnishings, and insufficient ventilation rates. The I/O ratio for HCHO was 6.32 during the autumn, and the indoor HCHO concentrations (mean = 0.16 ppm) in schools constructed within 1 year were significantly higher than the Korean Indoor Air Standard, indicating that schools have indoor sources of HCHO. Therefore, increasing the ventilation rate by means of a mechanical system and the use of low-emission furnishings can play key roles in improving the indoor air quality within schools.

Abstract  We conducted a multicity time-series study using monitoring data to assess seasonal patterns of short-term ozone-mortality association among elderly aged 65 years and over in Japan. Daily exposure to ambient ozone was computed using hourly measurements of photochemical oxidants available at multiple monitoring stations in each city. Effects of ozone on daily all-cause non-accidental, cardiovascular, and respiratory mortality were estimated using distributed lag linear models, controlling for confounding by temporal, day of the week, temperature, and flu epidemics. City-level effect estimates were combined using inverse variance meta-analysis. In spring and autumn, a 10-ppbv increase of daily maximum 8-h average ozone concentration in the previous 3 days was associated with 0.69 % (95 % confidence interval (CI): 0.27-1.10), 1.07 % (0.34-1.82), and 1.77 % (0.78-2.77) increases in daily all-cause, cardiovascular, and respiratory mortality, respectively. Forward displacement of respiratory mortality was large during the cold season despite lower ozone concentration. Results were generally independent of fine particulate matter and nitrogen dioxide. Findings suggest significant mortality effects of short-term ozone exposure among the elderly during the moderate season. Those with underlying respiratory diseases were susceptible, even during winter.

Abstract  Rationale: Cohort evidence linking long-term exposure to outdoor particulate air pollution and mortality has come largely from the United States. There is relatively little evidence from nationally representative cohorts in other countries. Objectives: To investigate the relationship between long-term exposure to a range of pollutants and causes of death in a national English cohort. Methods: A total of 835,607 patients aged 40-89 years registered with 205 general practices were followed from 2003-2007. Annual average concentrations in 2002 for particulate matter with a median aerodynamic diameter less than 10 (PM10) and less than 2.5 μm (PM2.5), nitrogen dioxide (NO2), ozone, and sulfur dioxide (SO2) at 1 km(2) resolution, estimated from emission-based models, were linked to residential postcode. Deaths (n = 83,103) were ascertained from linkage to death certificates, and hazard ratios (HRs) for all- and cause-specific mortality for pollutants were estimated for interquartile pollutant changes from Cox models adjusting for age, sex, smoking, body mass index, and area-level socioeconomic status markers. Measurements and Main Results: Residential concentrations of all pollutants except ozone were positively associated with all-cause mortality (HR, 1.02, 1.03, and 1.04 for PM2.5, NO2, and SO2, respectively). Associations for PM2.5, NO2, and SO2 were larger for respiratory deaths (HR, 1.09 each) and lung cancer (HR, 1.02, 1.06, and 1.05) but nearer unity for cardiovascular deaths (1.00, 1.00, and 1.04). Conclusions: These results strengthen the evidence linking long-term ambient air pollution exposure to increased all-cause mortality. However, the stronger associations with respiratory mortality are not consistent with most US studies in which associations with cardiovascular causes of death tend to predominate.

Abstract  Exposure to household wood smoke from cooking is a risk factor for chronic obstructive lung disease among women in developing countries. The Randomized Exposure Study of Pollution Indoors and Respiratory Effects (RESPIRE) is a randomized intervention trial evaluating the respiratory health effects of reducing indoor air pollution from open cooking fires. A total of 504 rural Mayan women in highland Guatemala aged 15-50 years, all using traditional indoor open fires, were randomized to either receive a chimney woodstove (plancha) or continue using the open fire. Assessments of chronic respiratory symptoms and lung function and individual measurements of carbon monoxide exposure were performed at baseline and every 6 months up to 18 months. Use of a plancha significantly reduced carbon monoxide exposure by 61.6%. For all respiratory symptoms, reductions in risk were observed in the plancha group during follow-up; the reduction was statistically significant for wheeze (relative risk = 0.42, 95% confidence interval: 0.25, 0.70). The number of respiratory symptoms reported by the women at each follow-up point was also significantly reduced by the plancha (odds ratio = 0.7, 95% confidence interval: 0.50, 0.97). However, no significant effects on lung function were found after 12-18 months. Reducing indoor air pollution from household biomass burning may relieve symptoms consistent with chronic respiratory tract irritation.

Abstract  Studies have found that indoor air pollution affects human, especially children and the elderly, more compared to ambient atmospheric air. This study aims to investigate respirable suspended particulate matter (RSP) concentration in selected primary schools with different surrounding human activities, and to establish statistical relationships between indoor and outdoor air pollutant concentrations in each selected schools in Kuala Terengganu. Failure to identify and establish indoor air pollution status can increase health problems for these young students and degrade their learning environment and comfort. Indoor air quality (IAQ) parameters in seven primary schools were conducted during the monsoon season of August 2008 until March 2009. In each classroom, RSP, air velocity, relative humidity and temperature were monitored during school hours, and a complete walkthrough survey was completed. Results show a statistically significant difference for the six IAQ parameters between the seven schools at the 95% confidence level. Indoor concentration levels were mainly affected by RSP of outdoor concentration levels, since there are strong relationships of RSP concentration between indoor and outdoor in all schools except for control school. We conclude our findings by confirming the important influence of surrounding human activities on indoor concentrations of pollutants at primary schools in Kuala Terengganu.

Abstract  Mechanical ventilation has been used since the middle 19(th) century as an effective method of providing acceptable conditions of indoor air in buildings. Mechanical ventilation systems have traditionally been the method of choice by which to ventilate hospitality venues where smoking occurs indoors. Mechanical ventilation systems work by introducing air into and moving air through buildings to achieve indoor air quality that is comparable to outdoor air quality. The Federation of European Heating and Air-Conditioning Associations (REHVA) in Guideline 4 "Ventilation and smoking: Reducing the exposure to ETS in buildings" provides guidance on best practices to achieve effective ventilation for hospitality venues and other buildings where smoking occurs (REHVA 2004). REHVA recognizes this topic as extremely important in respect to indoor air quality and energy consumption. The recently approved European Union (EN) EN/DIN Standard 15251 "Indoor environmental input parameters for design and assessment of energy performance of buildings addressing indoor air quality, thermal environment, lighting and acoustics "recommends specific ventilation rates for spaces in buildings where smoking is allowed (CEN- EN/DIN Standard 15251). Questions have been recently raised about the effect of mechanical ventilation systems on indoor air quality in hospitality venues where smoking is allowed. We have reviewed the literature available about effective mechanical ventilation and tobacco smoke and have found that very few studies purporting to establish the effect of ventilation on tobacco smoke in hospitality venues have actually measured and quantified ventilation parameters. In fact, many of these studies have not measured and quantified indoor air quality or tobacco smoke. Further although there are a few studies that have measured and reported ventilation, indoor air quality and environmental tobacco smoke (ETS) parameters, most of the hospitality venues included in these studies do not have effective ventilation systems. In addition, some of the studies appear to have misclassified air filtration (cleaning) and air conditioning systems as ventilation systems.

There is a dearth of data with which to determine the relationship between effective ventilation and tobacco smoke inhospitality venues where smoking occurs. These field studies of hospitality venues in the United States and the United Kingdom was undertaken in order to obtain field data on this relationship. The objectives of these field studies were to evaluate the performance of mechanical ventilation systems in various types and configurations of hospitality venues in both the United States and the United Kingdom to determine the effectiveness of these systems in providing acceptable indoor air quality in spaces where smoking is allowed. These field studies of six hospitality venues on two continents included ventilation and indoor air quality measurements of three casinos, two pubs and one restaurant.

This paper presents measurements of ventilation and indoor air quality including environmental tobacco smoke parameters sampled in several locations within each of the six venues to assess the effectiveness of mechanical ventilation. The indoor air quality measurements included carbon dioxide, carbon monoxide, total volatile organic compounds, temperature, relative humidity and respirable suspended particles. Measurements were also taken in the outdoor air as a means of comparing outdoor air quality with the indoor air quality.

The data from the field studies shows that mechanical ventilation is an effective means of providing indoor air quality conditions that are comparable to the outdoor air quality in hospitality venues where smoking is permitted.

Abstract  Background: Seasonal and regional differences have been reported for the increase in short-term mortality associated with a given increase in the concentration of outdoor particulate matter with an aerodynamic diameter smaller than 10 mu m (PM10 mortality coefficient). Some of this difference may be because of seasonal and regional differences in indoor exposure to PM10 of outdoor origin.

Methods: From a previous study, we obtained PM10 mortality coefficients for each season in seven U.S. regions. We then estimated the change in the sum of indoor and outdoor PM10 exposure per unit change in outdoor PM10 exposure (PM10 exposure coefficient) for each season in each region. This was originally accomplished by estimating PM10 exposure coefficients for 19 cities within the regions for which we had modeled building infiltration rates. We subsequently expanded the analysis to include 64 additional cities with less well-characterized building infiltration rates.

Results: The correlation (r = 0.71 [95% confidence interval = 0.46 to 0.86]) between PM10 mortality coefficients and PM10 exposure coefficients (28 data pairs; four seasons in each of seven regions) was strong using exposure coefficients derived from the originally targeted 19 National Morbidity, Mortality, and Air Pollutions Study cities within the regions. The correlation remained strong (r = 0.67 [0.40 to 0.84]) when PM10 exposure coefficients were derived using 83 cities within the regions (the original 19 plus the additional 64).

Conclusions: Seasonal and regional differences in PM10 mortality coefficients appear to partially reflect seasonal and regional differences in total PM10 exposure per unit change in outdoor exposure.

Abstract  Atmospheric aerosol particles are able to act as cloud condensation nuclei (CCN) and are therefore important for the climate and the hydrological cycle, but their properties are not fully understood. Total CCN number concentrations at 10 different supersaturations in the range of SS=0.12-1.18% were measured in May 2008 at the remote high alpine research station, Jungfraujoch, Switzerland (3580 m a.s.l.). In this paper, we present a closure study between measured and predicted CCN number concentrations. CCN predictions were done using dry number size distribution (scanning particle mobility sizer, SMPS) and bulk chemical composition data (aerosol mass spectrometer, AMS, and multi-angle absorption photometer, MAAP) in a simplified Kohler theory. The predicted and the measured CCN number concentrations agree very well and are highly correlated. A sensitivity study showed that the temporal variability of the chemical composition at the Jungfraujoch can be neglected for a reliable CCN prediction, whereas it is important to know the mean chemical composition. The exact bias introduced by using a too low or too high hygroscopicity parameter for CCN prediction was further quantified and shown to be substantial for the lowest supersaturation.

Despite the high average organic mass fraction (similar to 45%) in the fine mode, there was no indication that the surface tension was substantially reduced at the point of CCN activation. A comparison between hygroscopicity tandem differential mobility analyzer (HTDMA), AMS/MAAP, and CCN derived kappa values showed that HTDMA measurements can be used to determine particle hygroscopicity required for CCN predictions if no suitable chemical composition data are available.

Abstract  This paper presents a study of IAQ in toilets located in the Faculty of Civil and Environmental Engineering building, Universiti Tun Hussein Onn Malaysia (UTHM). This study was conducted to determine the level of gas pollutants exist in the male and female toilets. The important IAQ parameters considered in this study are SO2, NO, and CO2. The measurements were conducted during break hour and taken using air quality monitoring. The result indicated that SO2 exceeded the threshold value and this could have adverse effect on inhalation such as asthmatic. Finally, the existing SO2 was affected by mechanical ventilation mode, while the existing CO2 was more generated in female toilet.

Abstract  We present an approach to constrain simulated atmospheric black carbon (BC) using carbon monoxide (CO) observations. The approach uses: (1) the Community Atmosphere Model with Chemistry to simulate the evolution of BC and CO within an ensemble of model simulations; (2) satellite CO retrievals from the MOPITT/Terra instrument to assimilate observed CO into these simulations; (3) the derived sensitivity of BC to CO within these simulations to correct the simulated BC distributions. We demonstrate the performance of this approach through model experiments with and without the BC corrections during the period coinciding with the Intercontinental Chemical Transport Experiment (INTEX-B). Our results show significant improvements (similar to 50%) in median BC profiles using constraints from MOPITT, based on comparisons with INTEX-B measurements. We find that assimilating MOPITT CO provides considerable impact on simulated BC concentrations, especially over source regions. This approach offers an opportunity to augment our current ability to predict BC distributions. Citation: Arellano, A. F., Jr., P. G. Hess, D. P. Edwards, and D. Baumgardner (2010), Constraints on black carbon aerosol distribution from Measurement of Pollution in the Troposphere (MOPITT) CO, Geophys. Res. Lett., 37, L17801, doi: 10.1029/2010GL044416.