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Fine Particle, Ozone Exposure, and Asthma/Wheezing: Effect Modification by Glutathione S-transferase P1 Polymorphisms  [PDF]
Bing-Fang Hwang, Li-Hao Young, Ching-Hui Tsai, Kuan-Yen Tung, Pei-Chuan Wang, Ming-Wei Su, Yungling Leo Lee
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0052715
Abstract: Background There are limited studies on the role of interaction between exposure to ambient air pollution and glutathione-S-transferase (GST) P1 on the risk of asthma/wheezing among children, which provided suggestive, but inconclusive results. Methods To assess the joint effect of air pollutants and GSTP1 on asthma/wheezing, we conducted a nationwide cross-sectional study of 3,825 children in Taiwan Children Health Study. The studied determinants were three GSTP1 Ile105Val (rs 1695) genotypes (Ile-Ile; Ile-Val and Val-Val) and expoure to ambient air pollutants. We used routine air-pollution monitoring data for ozone (O3) and particles with an aerodynamic diameter of 2.5 μm or less (PM2.5). The effect estimates were presented as odds ratios (ORs) per interquartile changes for PM2.5 and O3. Findings In a two-stage hierarchical model adjusting for confounding, the risk of asthma was negatively associated with PM2.5 (adjusted odds ratio (OR) 0.60; 95% confidence interval (CI) 0.45, 0.82) and O3 (OR 0.74; 95% CI 0.60, 0.90) among Ile105 homozygotes, but positively associated with PM2.5 (OR 1.52; 95% CI 1.01, 2.27) and O3 (OR 1.19; 95% CI 0.91, 1.57) among those with at least one val105 allele (interaction p value = 0.001 and 0.03, respectively). A similar tendency of effect modification between PM2.5 and O3 and GSTP1 on wheezing was found. Conclusion Children who carried Ile105 variant allele and exposed to PM2.5 and O3 may be less likely to occurrence of asthma/wheezing.
Treatment of Asthma in the Elderly: Questionnaire Survey in Japan  [PDF]
Sahoko Chiba, Kimitake Tsuchiya, Tomoyuki Ogata, Reina Imase, Tamon Yagi, Yuka Mishima, Torahiko Jinta, Kazuhito Saito, Reiko Taki, Susumu Isogai, Yasuto Jinn, Tsutomu Kawasaki, Ichiro Natsume, Yoshihiro Miyashita, Jun Takagiwa, Nobuo Ishiwata, Tomoshige Chiaki, Masato Kishi, Yoshikazu Tsukada, Motohisa Yamasaki, Naohiko Inase
International Journal of Clinical Medicine (IJCM) , 2017, DOI: 10.4236/ijcm.2017.84023
Abstract: Introduction: The prevalence of asthma in the elderly has been increasing due to the aging of the global population. Appropriate treatment for asthma in the elderly is now a major issue, as the disease is often fatal and incurs high medical costs in the elderly population. There have been few recent reports on asthma treatment for the elderly in the real-world clinical settings. Objectives: This study was performed to assess how respiratory physicians manage asthma in elderly patients in clinical settings in Japan. Methods: Respiratory physicians in 16 Japanese hospitals responded to a questionnaire survey on asthma and COPD treatment between December 2014 and February 2015. The analysis was performed using data collected from medical records on 2041 asthma patients. Results: The mean patient age was 61.2 years, and 36.6% of the patients were men. In the breakdown by age, 1018 (49.9%) of the patients were elderly (≥ 65 years). Compared to the non-elderly, the elderly patients had a significantly lower BMI, greater smoking history in pack-years, and poorer pulmonary function. There were no significant differences between the elderly and non-elderly in the prescription rates of common medications such as inhaled corticosteroids, long-acting beta-agonists (LABA) administered via inhaler or transdermal patch, long-acting muscarinic antagonists, or leukotriene receptor antagonists. In contrast, mucoactive drugs (18.7% vs. 12.3%, P < 0.01) and macrolides (7.9% vs. 4.0%, P < 0.01) were prescribed more frequently for the elderly than for the non-elderly. The proportion of patients receiving transdermal LABA was higher in the elderly than in the non-elderly (4.7% vs. 2.4%, P = 0.02). Conclusions: According to this survey, the prescription rates of mucoactive drugs, macrolides, and transdermal LABA were significantly higher in the elderly than in the non-elderly.
Theoretical implication of reversals of the ozone weekend effect systematically observed in Japan
A. Kannari,T. Ohara
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2010,
Abstract: Systematic changes of the ozone weekend effect are found over broad areas of Japan. These changes are characterized by (1) spatial reversals from a weekend increase in the vicinity of huge precursor source areas to a weekend decrease in the surrounding rural areas, and (2) temporal reversals from a weekend increase under relatively unsuitable meteorological conditions for ozone formation to a weekend decrease under relatively suitable conditions. We developed a simple numerical advection–reaction model to explain the relationship between the duration of advection and the supplied solar energy, which causes the daily maximum ozone concentration to be lower near the precursor source. Ozone isopleth diagrams for individual advection durations (equivalent to the distance from the source) for a wide range of initial precursor conditions show that both VOC-limited and NOx-limited regimes exist for each advection duration, but the area of NOx-limited regime becomes dominant as the advection duration increases because of the increased exposure of the air mass to solar energy. For given initial VOC and NOx concentrations, the area remote from the source becomes a NOx-limited regime even if the precursor source area is in the VOC-limited regime. The rate of reduction of weekend emissions of NOx is larger than that of VOC, causing a weekend increase in ozone inside an area of VOC-limited regime near the source, but a weekend decrease in remote areas with a NOx-limited regime. The boundary between these two ozone formation regimes depends on meteorological conditions: when sunlight intensity and temperature are relatively low, the change from a VOC-limited to a NOx-limited regime occurs at a point more remote from the source than when they are relatively high, which causes a prevailing ozone weekend increase over a wide geographical area on days with lower ozone potential. Therefore, observations of ozone weekend changes can be interpreted in light of the theoretical implications of our model; they can be used for determination of ozone formation regimes, which change in different locations and under different meteorological conditions.
Theoretical implication of reversals of the ozone weekend effect systematically observed in Japan  [PDF]
A. Kannari,T. Ohara
Atmospheric Chemistry and Physics Discussions , 2009,
Abstract: Systematic changes of the ozone weekend effect are found over broad areas of Japan. These changes are characterized by (1) spatial reversals from a weekend increase in the vicinity of huge precursor source areas to a weekend decrease in the surrounding rural areas, and (2) temporal reversals from a weekend increase under relatively unsuitable meteorological conditions for ozone formation to a weekend decrease under relatively suitable conditions. We developed a simple numerical advection-reaction model to explain the relationship between the duration of advection and the supplied solar energy, which causes the daily maximum ozone concentration to be lower near the precursor source. Ozone isopleth diagrams for individual advection durations (equivalent to the distance from the source) for a wide range of initial precursor conditions show that both VOC-limited and NOx-limited regimes exist for each advection duration, but the area of NOx-limited regime becomes dominant as the advection duration increases because of the increased exposure of the air mass to solar energy. For given initial VOC and NOx concentrations, the area remote from the source becomes a NOx-limited regime even if the precursor source area is in the VOC-limited regime. The rate of reduction of weekend emissions of NOx is larger than that of VOC, causing a weekend increase in a VOC-limited regime near the source, but a weekend decrease in remote areas with a NOx-limited regime. The boundary between these two ozone formation regimes depends on meteorological conditions: when sunlight intensity and temperature are relatively low, the change from a VOC-limited to a NOx-limited regime occurs at a point more remote from the source than when they are relatively high, which causes a prevailing ozone weekend increase over a wide geographical area on days with lower ozone potential. Therefore, observations of ozone weekend changes can be interpreted in light of the theoretical implications of our model; they can be used for determination of ozone formation regimes, which change in different locations and under different meteorological conditions.
Influence of meteorological variability on interannual variations of the springtime boundary layer ozone over Japan during 1981–2005  [PDF]
J. Kurokawa,T. Ohara,I. Uno,M. Hayasaki
Atmospheric Chemistry and Physics Discussions , 2009,
Abstract: We investigated the influence of meteorological variability on the interannual variation of the springtime boundary layer ozone over Japan during 1981–2005 by multiyear simulations with the Models-3 Community Multiscale Air Quality (CMAQ) modeling system and the Regional Emission Inventory in Asia (REAS). CMAQ/REAS generally reproduced the observed interannual variability of springtime ozone over Japan, showing year-to-year variations larger than the annual rate of increase of the long-term trend. We then analyzed the influence of the interannual variation of meteorological fields in simulated results by using the fixed emissions for 2000 and meteorology data for each year. As a reference parameter, we calculated the area-weighted surface pressure anomaly over the Pacific Ocean east of Japan. When the anomaly has a large negative value, polluted air masses from continental Asia tend to be transported directly to Japan by westerly winds. In contrast, when the anomaly has a large positive value, the influences of the outflow from continental Asia tends to be small because the westerly components of wind fields around Japan are comparatively weak. Instead, southerly winds are relatively strong and transport clean air masses from the Pacific Ocean to Japan. Consequently, springtime ozone over Japan is higher (lower) than in ordinary years when the anomaly has a large negative (positive) value. In general, the interannual variation of springtime ozone over Japan is sensitive to the outflow from continental Asia. We also found some correlation between springtime ozone over Japan and the El Ni o-Southern Oscillation, indicating that higher and lower springtime ozone over Japan are related to La Ni a and El Ni o, respectively. Differences in the meridional displacement and diversity of cyclone tracks near Japan between El Ni o and La Ni a years may be responsible for interannual variations in the springtime boundary layer ozone over Japan.
Influence of meteorological variability on interannual variations of springtime boundary layer ozone over Japan during 1981–2005  [PDF]
J. Kurokawa,T. Ohara,I. Uno,M. Hayasaki
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2009,
Abstract: We investigated the influence of meteorological variability on the interannual variation of springtime boundary layer ozone over Japan during 1981–2005 by multiyear simulations with the Models-3 Community Multiscale Air Quality (CMAQ) modeling system and the Regional Emission Inventory in Asia (REAS). CMAQ/REAS generally reproduced the observed interannual variability of springtime ozone over Japan, showing year-to-year variations larger than the annual rate of increase of the long-term trend. We then analyzed the influence of the interannual variation of meteorology in simulated results by using the fixed emissions for 2000 and meteorological fields for each year. As a reference parameter, we calculated the area-weighted surface pressure anomaly over the Pacific Ocean east of Japan. When the anomaly has a large negative value, polluted air masses from continental Asia tend to be transported directly to Japan by westerly winds. In contrast, when the anomaly has a large positive value, influence of the outflow from continental Asia tends to be small because the westerly components of wind fields around Japan are comparatively weak. Instead, southerly winds are relatively strong and transport clean air masses from the Pacific Ocean to Japan. Consequently, springtime ozone over Japan is higher (lower) than in ordinary years when the anomaly has a large negative (positive) value. In general, the interannual variation of springtime ozone over Japan is sensitive to the outflow from continental Asia. We also found some correlation between springtime ozone over Japan and the El Ni o-Southern Oscillation, indicating that higher and lower springtime ozone over Japan are related to La Ni a and El Ni o, respectively. Differences in the meridional displacement and diversity of cyclone tracks near Japan between El Ni o and La Ni a years may be responsible for interannual variations in the springtime boundary layer ozone over Japan.
Attribution of projected changes in summertime US ozone and PM2.5 concentrations to global changes
J. Avise, J. Chen, B. Lamb, C. Wiedinmyer, A. Guenther, E. Salathé,C. Mass
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2009,
Abstract: The impact that changes in future climate, anthropogenic US emissions, background tropospheric composition, and land-use have on summertime regional US ozone and PM2.5 concentrations is examined through a matrix of downscaled regional air quality simulations, where each set of simulations was conducted for five months of July climatology, using the Community Multi-scale Air Quality (CMAQ) model. Projected regional scale changes in meteorology due to climate change under the Intergovernmental Panel on Climate Change (IPCC) A2 scenario are derived through the downscaling of Parallel Climate Model (PCM) output with the MM5 meteorological model. Future chemical boundary conditions are obtained through downscaling of MOZART-2 (Model for Ozone and Related Chemical Tracers, version 2.4) global chemical model simulations based on the IPCC Special Report on Emissions Scenarios (SRES) A2 emissions scenario. Projected changes in US anthropogenic emissions are estimated using the EPA Economic Growth Analysis System (EGAS), and changes in land-use are projected using data from the Community Land Model (CLM) and the Spatially Explicit Regional Growth Model (SERGOM). For July conditions, changes in chemical boundary conditions are found to have the largest impact (+5 ppbv) on average daily maximum 8-h (DM8H) ozone. Changes in US anthropogenic emissions are projected to increase average DM8H ozone by +3 ppbv. Land-use changes are projected to have a significant influence on regional air quality due to the impact these changes have on biogenic hydrocarbon emissions. When climate changes and land-use changes are considered simultaneously, the average DM8H ozone decreases due to a reduction in biogenic VOC emissions ( 2.6 ppbv). Changes in average 24-h (A24-h) PM2.5 concentrations are dominated by projected changes in anthropogenic emissions (+3 μg m 3), while changes in chemical boundary conditions have a negligible effect. On average, climate change reduces A24-h PM2.5 concentrations by 0.9 μg m 3, but this reduction is more than tripled in the Southeastern US due to increased precipitation and wet deposition.
Attribution of projected changes in US ozone and PM2.5 concentrations to global changes  [PDF]
J. Avise,J. Chen,B. Lamb,C. Wiedinmyer
Atmospheric Chemistry and Physics Discussions , 2008,
Abstract: The impact that changes in future climate, anthropogenic US emissions, background tropospheric composition, and land-use have on regional US ozone and PM2.5 concentrations is examined through a matrix of downscaled regional air quality simulations using the Community Multi-scale Air Quality (CMAQ) model. Projected regional scale changes in meteorology due to climate change under the Intergovernmental Panel on Climate Change (IPCC) A2 scenario are derived through the downscaling of Parallel Climate Model (PCM) output with the MM5 meteorological model. Future chemical boundary conditions are obtained through downscaling of MOZART-2 (Model for Ozone and Related Chemical Tracers, version 2.4) global chemical model simulations based on the IPCC Special Report on Emissions Scenarios (SRES) A2 emissions scenario. Projected changes in US anthropogenic emissions are estimated using the EPA Economic Growth Analysis System (EGAS), and changes in land-use are projected using data from the Community Land Model (CLM) and the Spatially Explicit Regional Growth Model (SERGOM). For July conditions, changes in chemical boundary conditions are found to have the largest impact (+5 ppbv) on average daily maximum 8-h (DM8H) ozone. Changes in US anthropogenic emissions are projected to increase average DM8H ozone by +3 ppbv. Land-use changes are projected to have a significant influence on regional air quality due to the impact these changes have on biogenic hydrocarbon emissions. When climate changes and land-use changes are considered simultaneously, the average DM8H ozone decreases due to a reduction in biogenic VOC emissions ( 2.6 ppbv). Changes in average 24-h (A24-h) PM2.5 concentrations are dominated by projected changes in anthropogenic emissions (+3 μg m 3), while changes in chemical boundary conditions have a negligible effect. On average, climate change reduces A24-h PM2.5 concentrations by 0.9 μg m 3, but this reduction is more than tripled in the Southeastern US due to increased precipitation and wet deposition.
A comparison between stomatal ozone uptake and AOT40 of deciduous trees in Japan
Hoshika Y,Shimizu Y,Omasa K
iForest : Biogeosciences and Forestry , 2011, DOI: 10.3832/ifor0573-004
Abstract: A comparison of the maps of stomatal ozone uptake (AFst0) and concentrations exceeding 40 ppb (AOT40) for dominant temperate deciduous tree species (Quercus serrata, Fagus crenata, Betula ermanii) was conducted in Japan. Estimations of stomatal ozone uptake were accomplished using estimated ozone concentration, climate data, and vegetation data. Key parameters such as stomatal conductance parameters for each species were collected from scientific literature in Japan. Stomatal closure induced by vapour pressure deficit affected the AFst0 values in warmer part of Japan. For this reason, the areas with high AOT40 did not always correspond to the areas with high AFst0. The result showed that ozone risk assessment using AOT40 is VPD-constrained in central Japan, which implies an overestimation of risk compared to AFst0. While in Europe AOT40 is higher where water stress is recurrent, AOT40 peaked in the cool and humid climate region of central-eastern Japan where also stomatal ozone uptake reached maximum values.
The January 2006 low ozone event over the UK
M. Keil, D. R. Jackson,M. C. Hort
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2007,
Abstract: In this paper we present a case study of a record low ozone event observed over the UK in January 2006. We focus on the dynamical processes that cause this event. This is done by examining the observations, meteorological analyses and back trajectories calculated by the NAME III atmospheric dispersion model. We show that this model, hitherto only used for tropospheric pollution studies, can be an important and effective tool for the examination of transport in the upper troposphere/lower stratosphere (UTLS) and mid-stratosphere regions. A record low total ozone column of 177 DU was observed at Reading, UK, on 19 January 2006. Low ozone values were also recorded at other stations in Northwest Europe around this date. Ozonesonde measurements indicate the depletion is occurring in two distinct vertical regions, with around a third of the reduction in total ozone column values originating from the mid-stratosphere and the rest from the UTLS region. Evidence suggests that air inside the stratospheric polar vortex was poor in ozone prior to 19 January and the occurrence of a major stratospheric warming shifted this air over Northwest Europe. In addition we show that moderate ozone depletion, related to the lifting of the tropopause and divergence in the lower stratosphere associated with the presence of an anticyclone, is also a plausible mechanism for the record low ozone column that is observed. In order to confirm that both mid-stratosphere and UTLS transport processes are responsible for the record low ozone values, we perform turbulent back trajectory calculations using the Met Office NAME III model. The results show that air parcels in the mid-stratosphere that arrive over the British Isles on 19 January originate in the polar vortex, and furthermore that air parcels near the tropopause arrive from low latitudes and are transported anticyclonically. Therefore this strongly suggests that the record low ozone values are due to a combination of a raised tropopause with increased divergence in the lower stratosphere and the presence of low ozone stratospheric air aloft.
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