Land use regression (LUR) model was employed to predict the spatial concentration distribution of NO2 and PM10 in the Tianjin region based on the environmental air quality monitoring data. Four multiple linear regre...Land use regression (LUR) model was employed to predict the spatial concentration distribution of NO2 and PM10 in the Tianjin region based on the environmental air quality monitoring data. Four multiple linear regression (MLR) equations were established based on the most significant variables for NO2 in heating season (R2 = 0.74), and non-heating season (R2 = 0.61) in the whole study area; and PM10 in heating season (R2 = 0.72), and non-heating season (R2 = 0.49). Maps of spatial concentration distribution for NO2 and PM10 were obtained based on the MLR equations (resolution is 10 krn). Intercepts of MLR equations were 0.050 (NOz, heating season), 0.035 (NO2, non-heating season), 0.068 (PM10, heating season), and 0.092 (PM10, non-beating season) in the whole study area. In the central area of Tianjin region, the intercepts were 0.042 (NO2, heating season), 0.043 (NO2, non-heating season), 0.087 (PM10, heating season), and 0.096 (PMl0, non-heating season). These intercept values might imply an area's background concentrations. Predicted result derived from LUR model in the central area was better than that in the whole study area. Rz values increased 0.09 (heating season) and 0.18 (non-heating season) for NO2, and 0.08 (heating season) and 0.04 (non-heating season) for PMl0. In terms of R2, LUR model performed more effectively in heating season than non-heating season in the study area and gave a better result for NOz compared with PM10.展开更多
SO2, NO2, and PM10 are the major outdoor air pollutants in China, and most of the cities in China have regulatory monitoring sites for these three air pollutants. In this study, we developed a land use regression (LUR...SO2, NO2, and PM10 are the major outdoor air pollutants in China, and most of the cities in China have regulatory monitoring sites for these three air pollutants. In this study, we developed a land use regression (LUR) model using regulatory monitoring data to predict the spatial distribution of air pollutant concentrations in Jinan, China. Traffic, land use and census data, and meteorological and physical conditions were included as candidate independent variables, and were tabulated for buffers of varying radii. SO2, NO2, and PM10 concentrations were most highly correlated with the area of industrial land within a buffer of 0.5 km (R2=0.34), the distance from an expressway (R2=0.45), and the area of residential land within a buffer of 1.5 km (R2=0.25), respectively. Three multiple linear regression (MLR) equations were established based on the most significant variables (p<0.05) for SO2, NO2, and PM10, and R2 values obtained were 0.617, 0.640, and 0.600, respectively. An LUR model can be applied to an area with complex terrain. The buffer radii of independent variables for SO2, NO2, and PM10 were chosen to be 0.5, 2, and 1.5 km, respectively based on univariate models. Intercepts of MLR equations can reflect the background concentrations in a certain area, but in this study the intercept values seemed to be higher than background concentrations. Most of the cities in China have a network of regulatory monitoring sites. However, the number of sites has been limited by the level of financial support available. The results of this study could be helpful in promoting the application of LUR models for monitoring pollutants in Chinese cities.展开更多
Prevalence of allergic rhinitis has rapidly increased among Chinese children,but the reasons are unclear.Recent findings have suggested that exposure to outdoor air pollutants may increase the risk of allergic rhiniti...Prevalence of allergic rhinitis has rapidly increased among Chinese children,but the reasons are unclear.Recent findings have suggested that exposure to outdoor air pollutants may increase the risk of allergic rhinitis,but the results were inconsistent.This study further investigated the effect of outdoor air pollutants on allergic rhinitis among preschool children.A standardized questionnaire on health,home and environmental factors was conducted for 4988 children aged 1–8 in the city of Changsha,and the concentrations of PM10(particle diameter 10 m),sulfur dioxide(SO2)and nitrogen dioxide(NO2)during 2006–2011 were acquired from the official web of Changsha Environmental Protection Agency.Results showed that the prevalence of children’s doctor diagnosed rhinitis was 8.4%(95%confidence interval[CI]7.0%–10.0%).It was found that the prevalence of rhinitis was not associated with site-specific background concentrations of air pollutants,but significantly positively correlated with age-related accumulative personal exposure of PM10,SO2and NO2.We conclude that age-related accumulative personal exposure to ambient air pollution may play an important role in the development of rhinitis.展开更多
Polychlorinated biphenyls(PCBs) are stable in the environment,undergo long-range atmospheric transport,and possess the ability to bioaccumulate through the food chain which can impose a serious threat to human health ...Polychlorinated biphenyls(PCBs) are stable in the environment,undergo long-range atmospheric transport,and possess the ability to bioaccumulate through the food chain which can impose a serious threat to human health and the environment.Atmosphere is the major pathway for PCBs to transport and redistribute in the environment.In order to know levels and patterns of PCBs in background air in China,high-volume air samples were collected at 11 background sites from November 2007 to February 2008.PCBs were extracted from samples by accelerated solvent extraction(ASE) and then purified by acid silica column and fluid management systems(FMS).Confirmation and quantitative analysis were performed by HRGC-HRMS using voltage selective ion record mode.Total concentrations of dioxin-like PCBs in background air ranged from 348.8 fg/m3 to 1 768.3 fg/m3(0.7-7.4 fg TEQ/m3),and total concentrations of indicator PCBs were from 9.0 pg/m3 up to 85.2 pg/m3,which were both lower than the concentrations of most other regions and countries.展开更多
基金supported by the Special Environmental Research Funds for Public Welfare (No. 200709048,200909005)the National Natural Science Foundation of China (No. 20677030)
文摘Land use regression (LUR) model was employed to predict the spatial concentration distribution of NO2 and PM10 in the Tianjin region based on the environmental air quality monitoring data. Four multiple linear regression (MLR) equations were established based on the most significant variables for NO2 in heating season (R2 = 0.74), and non-heating season (R2 = 0.61) in the whole study area; and PM10 in heating season (R2 = 0.72), and non-heating season (R2 = 0.49). Maps of spatial concentration distribution for NO2 and PM10 were obtained based on the MLR equations (resolution is 10 krn). Intercepts of MLR equations were 0.050 (NOz, heating season), 0.035 (NO2, non-heating season), 0.068 (PM10, heating season), and 0.092 (PM10, non-beating season) in the whole study area. In the central area of Tianjin region, the intercepts were 0.042 (NO2, heating season), 0.043 (NO2, non-heating season), 0.087 (PM10, heating season), and 0.096 (PMl0, non-heating season). These intercept values might imply an area's background concentrations. Predicted result derived from LUR model in the central area was better than that in the whole study area. Rz values increased 0.09 (heating season) and 0.18 (non-heating season) for NO2, and 0.08 (heating season) and 0.04 (non-heating season) for PMl0. In terms of R2, LUR model performed more effectively in heating season than non-heating season in the study area and gave a better result for NOz compared with PM10.
基金Project supported by the National Natural Science Foundation of China (No. 20677030)the Development Plan of Key National Fun-damental Research (No. 2011CB503801)the Special Research Funds for Science Development in Jinan (No. 200904015), China
文摘SO2, NO2, and PM10 are the major outdoor air pollutants in China, and most of the cities in China have regulatory monitoring sites for these three air pollutants. In this study, we developed a land use regression (LUR) model using regulatory monitoring data to predict the spatial distribution of air pollutant concentrations in Jinan, China. Traffic, land use and census data, and meteorological and physical conditions were included as candidate independent variables, and were tabulated for buffers of varying radii. SO2, NO2, and PM10 concentrations were most highly correlated with the area of industrial land within a buffer of 0.5 km (R2=0.34), the distance from an expressway (R2=0.45), and the area of residential land within a buffer of 1.5 km (R2=0.25), respectively. Three multiple linear regression (MLR) equations were established based on the most significant variables (p<0.05) for SO2, NO2, and PM10, and R2 values obtained were 0.617, 0.640, and 0.600, respectively. An LUR model can be applied to an area with complex terrain. The buffer radii of independent variables for SO2, NO2, and PM10 were chosen to be 0.5, 2, and 1.5 km, respectively based on univariate models. Intercepts of MLR equations can reflect the background concentrations in a certain area, but in this study the intercept values seemed to be higher than background concentrations. Most of the cities in China have a network of regulatory monitoring sites. However, the number of sites has been limited by the level of financial support available. The results of this study could be helpful in promoting the application of LUR models for monitoring pollutants in Chinese cities.
基金supported by the National Natural Science Foundation of China(51178466)the Research Fund for the Doctoral Program of Higher Education of China(20120162110011)
文摘Prevalence of allergic rhinitis has rapidly increased among Chinese children,but the reasons are unclear.Recent findings have suggested that exposure to outdoor air pollutants may increase the risk of allergic rhinitis,but the results were inconsistent.This study further investigated the effect of outdoor air pollutants on allergic rhinitis among preschool children.A standardized questionnaire on health,home and environmental factors was conducted for 4988 children aged 1–8 in the city of Changsha,and the concentrations of PM10(particle diameter 10 m),sulfur dioxide(SO2)and nitrogen dioxide(NO2)during 2006–2011 were acquired from the official web of Changsha Environmental Protection Agency.Results showed that the prevalence of children’s doctor diagnosed rhinitis was 8.4%(95%confidence interval[CI]7.0%–10.0%).It was found that the prevalence of rhinitis was not associated with site-specific background concentrations of air pollutants,but significantly positively correlated with age-related accumulative personal exposure of PM10,SO2and NO2.We conclude that age-related accumulative personal exposure to ambient air pollution may play an important role in the development of rhinitis.
文摘Polychlorinated biphenyls(PCBs) are stable in the environment,undergo long-range atmospheric transport,and possess the ability to bioaccumulate through the food chain which can impose a serious threat to human health and the environment.Atmosphere is the major pathway for PCBs to transport and redistribute in the environment.In order to know levels and patterns of PCBs in background air in China,high-volume air samples were collected at 11 background sites from November 2007 to February 2008.PCBs were extracted from samples by accelerated solvent extraction(ASE) and then purified by acid silica column and fluid management systems(FMS).Confirmation and quantitative analysis were performed by HRGC-HRMS using voltage selective ion record mode.Total concentrations of dioxin-like PCBs in background air ranged from 348.8 fg/m3 to 1 768.3 fg/m3(0.7-7.4 fg TEQ/m3),and total concentrations of indicator PCBs were from 9.0 pg/m3 up to 85.2 pg/m3,which were both lower than the concentrations of most other regions and countries.