Annual Average Concentration Of PM2 Research Articles

Distribution and Health Risk Assessment of Heavy Metals in Atmospheric Particulate Matter and Dust

In order to study the concentration, distribution characteristics, and health risk assessment of toxic heavy metals, Cu, Mn, Pb, Ti, V, Cd, Cr, Co, Mo, and Ni, in atmospheric particulate matter (PM) and dust, the PM and dust samples were collected in all four seasons in 2014 in Beijing using two high volume air samplers (Echo Tecora Inc., Italy) and a dust tank, respectively. Selected metals were quantified by ICP-MS. Annual average concentrations of PM2.5 and PM10 were 153.40 μg·m-3 and 232.93 μg·m-3, which were five and three times higher than the Ambient Air Quality Standard values (GB 3095-2012), respectively. The average PM2.5/PM10 was 0.74, implying that PM2.5 predominated the particulate matter concentrations. The results of backward trajectory analysis suggested that exogenous particles originated from the northwest, north-northeast, southeast, and southeast-northwest during winter, spring, summer, and autumn, respectively. The order of annual average concentrations of selected metals in PM2.5 and PM10 was Ti > Mn > Pb > Cu > Cr > Ni > V > Cd > Mo > Co. The sum of the concentrations of Ti, Mn, Pb, Cu, and Cr accounted for 91.93% and 92.49% of the total concentration of target metals in PM2.5 and PM10, respectively. The metal content of dust followed the order of Ti > Mn > Pb > Cu > Ni > Cr > V > Co > Mo > Cd and Ti (2561.48 μg·g-1) accounted for 72.57% of the total metal content of dust. The geo-accumulation index (Igeo) of Cd, Pb, Cu, and Ni were 4.03, 2.49, 1.33, and 0.43, which represented the states of heavily to extremely contaminated, moderately to heavily contaminated, moderately contaminated and uncontaminated to moderately contaminated, respectively, indicating that dust in the target area included significant amounts of Cd, Pb, and Cu. The health risk assessment suggested that non-carcinogenic and carcinogenic risks of selected metals in PM10 and dust were within safe limits, but their long-term impact cannot be ignored.

Geographic variation in Chinese children’ forced vital capacity and its association with long-term exposure to local PM10: a national cross-sectional study

The purpose of this study was to estimate the association between Chinese children's forced vital capacity (FVC) and particulate matter with aerodynamic diameter ≤10μm (PM10). The FVC data of 71,763 children aged 7 to 18 was collected from 2010 Chinese National Survey on Students' Construction and Health (CNSSCH). The local annual average concentration of PM10, relative humidity, ambient temperature, and other air pollutant data of 30 cities was collected from China Meteorological Administration and Ministry of Environment Protection of China. Then, we used generalized additive model (GAM) to estimate the association between children's FVC and PM10. The obvious geographic variation in FVC was found in children of 30 Chinese cities ranging from 1647ml in Xining to 2571ml in Beijing. The annual average concentration of PM10 was also different, ranging from 40μg/m3 in Haikou to 155μg/m3 in Lanzhou. After adjusted individual characteristics, socioeconomic conditions, ambient temperature, relative humidity, and other air pollutants (e.g., NO2 and SO2) in the generalized additive model, we found that the increase of PM10 was associated with decrease of FVC in Chinese children. A 10-μg/m3 increase of PM10 was associated with 1.33-ml decrease in FVC (95% confidence interval: -2.18 to -0.47). We also found a larger effect estimate of PM10 on FVC in boys than that in girls. Consistent associations were found in both physically inactive and active children. The increase of PM10 was associated with decrease of children's FVC. We should develop proper public health policy to protect children's respiratory health during growth and development in polluted areas.

Association between air pollution and cardiovascular mortality in Hefei, China: A time-series analysis

In recent years, air pollution has become an alarming problem in China. However, evidence on the effects of air pollution on cardiovascular mortality is still not conclusive to date. This research aimed to assess the short-term effects of air pollution on cardiovascular morbidity in Hefei, China. Data of air pollution, cardiovascular mortality, and meteorological characteristics in Hefei between 2010 and 2015 were collected. Time-series analysis in generalized additive model was applied to evaluate the association between air pollution and daily cardiovascular mortality. During the study period, the annual average concentration of PM10, SO2, and NO2 was 105.91, 20.58, and 30.93 μg/m3, respectively. 21,816 people (including 11,876 man, and 14,494 people over 75 years of age) died of cardiovascular diseases. In single pollutant model, the effects of multi-day exposure were greater than single-day exposure of the air pollution. For every increase of 10 μg/m3 in SO2, NO2, and PM10 levels, CVD mortality increased by 5.26% (95%CI: 3.31%–7.23%), 2.71% (95%CI: 1.23%–4.22%), and 0.68% (95%CI: 0.33%–1.04%) at a lag03, respectively. The multi-pollutant models showed that PM10 and SO2 remained associated with CVD mortality, although the effect estimates attenuated. However, the effect of NO2 on CVD mortality decreased to statistically insignificant. Subgroup analyses further showed that women were more vulnerable than man upon air pollution exposure. These findings showed that air pollution could significantly increase the CVD mortality.

Ambient Particles (PM10, PM2.5 and PM1.0) and PM2.5 Chemical Components in Western Yangtze River Delta (YRD): An Overview of Data from 1-year Online Continuous Monitoring at Nanjing

Understanding particle chemical composition is important in source apportionment and health impact assessment. Since 2012, a Complex Air Pollution Research Station located on the top roof of a 22-floor building (~80 m) in Jiangsu Provincial Academy of Environmental Science was established as a platform to characterize components and temporal variations of hazy and air transport in the region, so as to provide scientific supports on Joint Prevention and Control of Regional Air Pollution control in the Yangtze River Delta. Here, based on 1-year online measurement, we present a preliminary result on occurrence of ambient particles and chemical components, and reconstructed light extinction coefficients based on measured species. In 2015, the annual average concentration of PM2.5 was 68 ± 40 µg/m3, comprising up to nearly 75% of the total PM10. The submicron PM1.0 had an annual average concentration of 48 ± 28 µg/m3 and contributed about 70% of the total PM2.5 mass. Secondary inorganic composition including sulfate, nitrate and ammonium (SNA) was the major fraction of PM2.5, accounting for ~70% on an annual average. The estimated light extinction of ambient particle averaged at 422 ± 256 Mm−1, of which 412 ± 257 Mm−1 was induced by fine PM2.5. SNA contributed largely to the light extinction induced by fine PM2.5 (about 72%), followed by organic matter (18%). During the high-pollution episodes, the mass fraction of SNA increased notably, calling for necessary controls on key gaseous precursors.

Two notable features in PM10 data and analysis of their causes

Hourly PM10 mass concentrations were collected from 25 air quality monitoring stations in Seoul, Korea. Sixteen years of data, from 2000 to 2015, were analyzed. During that time, the annual average PM10 concentrations declined almost linearly at a rate of −1.98 μg m−3 year−1. The number of high PM10 days declined faster than did the number of low PM10 days. This indicates that the bulk of the annual average PM10 mass concentration reduction was high-level PM10 concentrations. Further analysis of this data revealed two interesting points. First, though the annual average PM10 concentrations clearly lowered for period 1 (from 2000 to 2012; −2.28 μg m−3 year−1), they remained almost unchanged at a virtually constant value for period 2 (from 2012 to 2015; −0.02 μg m−3 year−1). Second, annual average PM10 concentrations showed a large spatial concentration gradient among all monitoring stations in the early 2000s. However, the spatial concentration gradient got gradually smaller until reaching a nearly no-gradient, uniform concentration among all monitoring stations from 2010 onward. Clear PM10 concentration reduction in period 1 was driven by local emission reduction. However, its reduction was not enough in period 2. The reduction of local emissions was negated by the increase of local activities and transported particulates, as well as the formation of secondary aerosol in Seoul from emissions transported from upwind regional sources. This resulted in PM10 concentrations becoming stagnant in period 2. PM10 reduction rate in the downwind area was faster than that in the upwind area. For the first 5 years, the reduction rate in the downwind area was great. Between all the stations observed, nearly all of the concentration difference was a result of more reduction in secondary aerosol. After 2005, coarse particles and primary elemental carbon (EC) played a key role in reducing the PM10 concentration. Our findings on these two data features, and their causes, will help people to understand the most recent characteristics of particulate matters, in turn helping to update the control strategy for the continued improvement of particulate air quality in Seoul.

National-scale exposure prediction for long-term concentrations of particulate matter and nitrogen dioxide in South Korea

The limited spatial coverage of the air pollution data available from regulatory air quality monitoring networks hampers national-scale epidemiological studies of air pollution. The present study aimed to develop a national-scale exposure prediction model for estimating annual average concentrations of PM10 and NO2 at residences in South Korea using regulatory monitoring data for 2010. Using hourly measurements of PM10 and NO2 at 277 regulatory monitoring sites, we calculated the annual average concentrations at each site. We also computed 322 geographic variables in order to represent plausible local and regional pollution sources. Using these data, we developed universal kriging models, including three summary predictors estimated by partial least squares (PLS). The model performance was evaluated with fivefold cross-validation. In sensitivity analyses, we compared our approach with two alternative approaches, which added regional interactions and replaced the PLS predictors with up to ten selected variables. Finally, we predicted the annual average concentrations of PM10 and NO2 at 83,463 centroids of residential census output areas in South Korea to investigate the population exposure to these pollutants and to compare the exposure levels between monitored and unmonitored areas. The means of the annual average concentrations of PM10 and NO2 for 2010, across regulatory monitoring sites in South Korea, were 51.63 μg/m3 (SD = 8.58) and 25.64 ppb (11.05), respectively. The universal kriging exposure prediction models yielded cross-validated R2s of 0.45 and 0.82 for PM10 and NO2, respectively. Compared to our model, the two alternative approaches gave consistent or worse performances. Population exposure levels in unmonitored areas were lower than in monitored areas. This is the first study that focused on developing a national-scale point wise exposure prediction approach in South Korea, which will allow national exposure assessments and epidemiological research to answer policy-related questions and to draw comparisons among different countries.

Cancer incidence attributable to air pollution in Alberta in 2012.

The International Agency for Research on Cancer has classified outdoor air pollution (fine particulate matter [PM2.5]) as a Group 1 lung carcinogen in humans. We aimed to estimate the proportion of lung cancer cases attributable to PM2.5 exposure in Alberta in 2012. Annual average concentrations of PM2.5 in 2011 for 22 communities across Alberta were extracted from the Clean Air Strategic Alliance Data Warehouse and were population-weighted across the province. Using 7.5 µg/m3 and 3.18 µg/m3 as the annual average theoretical minimum risk concentrations of PM2.5, we estimated the proportion of the population above this cut-off to determine the population attributable risk of lung cancer due to PM2.5 exposure. The mean population-weighted concentration of PM2.5 for Alberta in 2011 was 10.03 µg/m3. We estimated relative risks of 1.02 and 1.06 for theoretical minimum risk PM2.5 concentration thresholds of 7.5 µg/m3 and 3.18 µg/m3, respectively. About 1.87%-5.69% of incident lung cancer cases in Alberta were estimated to be attributable to PM2.5 exposure. Our estimate of attributable burden is low compared to that reported in studies in other areas of the world owing to the relatively low levels of PM2.5 recorded in Alberta. Reducing PM2.5 emissions in Alberta should continue to be a priority to help decrease the burden of lung cancer in the population.

Burden of disease attributed to ambient PM2.5 and PM10 exposure in 190 cities in China.

Particulate air pollution is becoming a serious public health concern in urban cities of China. Association of disability-adjusted life years (DALYs) and economic loss with air pollution-related health effects demand quantitative analysis for correctional measures in air quality. This study applies an epidemiology-based exposure-response function to obtain the quantitative estimate of health impact of particulate matter PM2.5 and PM10 across 190 cities of China during years 2014-2015. The annual average concentration of PM2.5 and PM10 is 57±18μg/m3 (ranging from 18 to 119μg/m3) and 97.7±34.2μg/m3 (ranging from 33.5 to 252.8μg/m3), respectively. Based on the present study, the total estimated annual premature mortality due to PM2.5 is 722,370 [95% confidence interval (CI)=322,716-987,519], 79% of which accounts for adult cerebrovascular disease (stroke) and ischemic heart disease (IHD). The premature mortality in megacities is very high, such as Chongqing (25,162/year), Beijing (19,702/year), Shanghai (19,617/year), Tianjin (13,726/year), and Chengdu (12,356/year). PM10 pollution has caused 1,491,774 (95% CI= 972,770-1,960,303) premature deaths (age >30) in China. Further, 3,614,064 cases of chronic bronchitis (CB); 13,759,894 cases of asthma attack among all ages; 191,709 COPD-related hospital admission (HA) cases; 499,048 respiratory-related HA; 357,816 cerebrovascular HA; and 308,129 cardiovascular-related HA due to PM10 pollution have been estimated during 2014-2015. Chongqing, Beijing, Baoding, Tianjin, and Shijiazhuang are the top five contributors to pollution-related mortality, accounting for 3.10, 2.71, 2.49, 2.20, and 2.02%, respectively, of the total deaths caused by PM10 pollution. The total DALYs associated with PM2.5 and PM10 pollution in China is 7.2 and 20.66 million in 2014-2015, and mortality and chronic bronchitis shared about 93.3% of the total DALYs for PM10. During this period, the economic cost of health impact due to PM10 is approximately US$304,122 million, which accounts for about 2.94% of China's gross domestic product (GDP). Megacities are expected to contribute relatively more to the total costs. The present methodology could be used as a tool to help policy makers and pollution control board authorities, to further analyze costs and benefits of air pollution management programs in China.

Dust deposition and ambient PM<sub>10</sub> concentration in northwest China: spatial and temporal variability

Abstract. Eolian dust transport and deposition are important geophysical processes which influence global bio-geochemical cycles. Currently, reliable deposition data are scarce in central and east Asia. Located at the boundary of central and east Asia, Xinjiang Province of northwestern China has long played a strategic role in cultural and economic trade between Asia and Europe. In this paper, we investigated the spatial distribution and temporal variation in dust deposition and ambient PM10 (particulate matter in aerodynamic diameter ≤ 10 µm) concentration from 2000 to 2013 in Xinjiang Province. This variation was assessed using environmental monitoring records from 14 stations in the province. Over the 14 years, annual average dust deposition across stations in the province ranged from 255.7 to 421.4 t km−2. Annual dust deposition was greater in southern Xinjiang (663.6 t km−2) than northern (147.8 t km−2) and eastern Xinjiang (194.9 t km−2). Annual average PM10 concentration across stations in the province varied from 100 to 196 µg m−3 and was 70, 115 and 239 µg m−3 in northern, eastern and southern Xinjiang, respectively. The highest annual dust deposition (1394.1 t km−2) and ambient PM10 concentration (352 µg m−3) were observed in Hotan, which is located in southern Xinjiang and at the southern boundary of the Taklamakan Desert. Dust deposition was more intense during the spring and summer than other seasons. PM10 was the main air pollutant that significantly influenced regional air quality. Annual average dust deposition increased logarithmically with ambient PM10 concentration (R2 ≥ 0.81). While the annual average dust storm frequency remained unchanged from 2000 to 2013, there was a positive relationship between dust storm days and dust deposition and PM10 concentration across stations. This study suggests that sand storms are a major factor affecting the temporal variability and spatial distribution of dust deposition in northwest China.

Elemental Composition and Concentration of Atmospheric Particulate Matter in Kuwait

Hourly PM10 and PM2.5 samples were simultaneously collected at 10 and 3 urban sites, respectively in Kuwait from March 2014 to February 2015, to study the air quality and heavy metals content and Total Petroleum Hydrocarbons (TPHs) in PM10 samples. The annual average concentrations of PM10 and PM2.5 were 152 and 97.3 μg/m3, respectively, with an average PM2.5/PM10 ratio of 70%. The contamination level of heavy metals in PM10 samples was assessed in terms of Enrichment Factor (EF) using mathematical models. The elements associated with an anthropogenic activity in the PM10 samples; i.e., Pb, Cu, Co, Cd and Zn, were 2.4, 12.9, 14.6, 42.6 and 156.2 times higher than the corresponding background values in Kuwait soil. TPH was the dominant pollutant in the PM10 samples. In general, most daily average Air Quality Indices (AQI) of PM10 concentrations fell under the categories of "good" and "moderate"

Trends of PM2.5 and Chemical Composition in Beijing, 2000-2015

ABSTRACTPM2.5 is the major pollutant in most cities of China, especially contributed significantly to the poor air quality in Beijing. This study aimed to investigate the long-term trend (2000–2015) of PM2.5, based on intensive observation and comprehensive literature investigation of PM2.5 and its chemical components. Results showed that the annual average concentration of PM2.5 generally decreased by 1.5 µg m–3 year–1 from 2000 to 2015 under the implementation of 16 phases’ air pollution control measures. In the most polluted season (winter), four change stages were found related with emission control effect and meteorological conditions: PM2.5 decreased in 2000–2008 and 2010–2013, increased in 2008–2010, and was at a high level in 2013–2015. As for detailed chemical components, OC, soil dust and typical elements (Si, Ca, Fe, Mn, Cu, Pb and K) presented a downward trend generally. EC had almost no change before 2003, increased from 2003 to 2007, but decreased after 2007; this may be caused by the replacement of fossil fuel and control of biomass emission. The continuous rising of OC/EC and SOC/OC (secondary organic carbon, SOC) in recent years illustrated the secondary carbonaceous species pollution is becoming serious. SO42– showed a slight increase from 2000–2013, but decreased obviously from 2013–2015. NO3– and NH4+ had an upward trend during the past decade. The proportion of secondary inorganic aerosol (SIA) increased at a rate of 0.7% yr–1, and it has become the major composition of PM2.5 in Beijing instead of carbonaceous component since 2009. In general, PM2.5 change trend indicated the emission mitigation measures implemented in Beijing have reduced the primary PM2.5 effectively. However, the control of secondary components should be paid special attention in order to further improve the air quality in Beijing effectively.

Chemical Composition Characteristics of PM2.5 in Three Cities in Henan, Central China

ABSTRACTThe sites of Luoyang, Zhengzhou, and Pingdingshan in Henan, China were selected to investigate the chemical compositions of fine particulate matter (PM2.5). A total of 165 PM2.5 samples from the three sites were collected from October 2014 to July 2015. Water-soluble inorganic ions, elemental carbon and organic carbon, and other elements in PM2.5 were analyzed by ion chromatography, carbon analyzer, and inductively coupled plasma mass spectrometry, respectively. Results showed that the annual average concentrations of PM2.5 in the three sites were significantly higher than the Chinese national ambient air quality standard. The seasonal average of PM2.5 concentration varied with the lowest concentrations of PM2.5 in summer. Among these sites, the highest concentrations of SO42– and NH4+ ions were observed in Luoyang with the highest concentration of NO3– detected in Zhengzhou. SO42–, NO3– and NH4+ ions occurred as (NH4)2SO4 and NH4NO3. For seasonal variation, the highest concentrations for Al, Fe and Ca were observed during spring in Pingdingshan and autumn in Zhengzhou and Luoyang, respectively. Enrichment factor (EF), as an indicator, is commonly used to evaluate the contribution of anthropogenic sources, and high EFs of Zn, Cu, and Cd in PM2.5 indicate the extent of air pollution, which is generally caused by emissions of vehicles and industries. Risks posed by heavy metals on human health were assessed. The hazard index, which was used to assess the overall potential for noncarcinogenic effects, was higher than 1 in the three sites, indicating that V, Cr, As, Mn, Cd, Co, and Ni may cause accumulative noncarcinogenic health effects on humans, without the noncancer effect of each heavy metal significant. Cr in PM2.5 is a potential carcinogenic risk when inhaled by adults. Overall, the results indicate that PM2.5 pollution must be considered seriously in three cities.

Assessment of population exposure to PM2.5 for mortality in China and its public health benefit based on BenMAP

Along with the rapid socioeconomic development, air pollution in China has become a severe problem. One component of air pollution, in particular, PM2.5 has aroused wide public concern because of its high concentration. In this study, data were collected from over 900 monitoring sites of the newly constructed PM2.5 monitoring network in China. The interpolation methods were used to simulate the PM2.5 exposure level of China especially in rural areas, thus reflecting the spatial variation of PM2.5 pollution. We calculated the health benefit caused by PM2.5 in China in 2014 based on Environmental Benefits Mapping and Analysis Program (BenMAP), assuming achievement of China National Ambient Air Quality Standard (No. GB3095-2012). By reducing the annual average concentration of PM2.5 to the annual Grade II standard (35 μg/m3), the avoided deaths for cardiovascular disease, respiratory disease and lung cancer could reach 89,000 (95% CI, 8000–170,000), 47,000 (95% CI, 3000–91,000) and 32,000 (95% CI, 6000–58,000) per year using long term health function, respectively. The attributable fractions of cardiovascular disease, respiratory disease and lung cancer to all cause were 42%, 22% and 15%, respectively. The total economic benefits for rolling back the concentration of PM2.5 to the level of 35 μg/m3 were estimated to be 260 (95%CI: (73, 440) billion RMB and 72 (95%CI: (45, 99) billion RMB using willingness to pay (WTP) and human capital (HC) methods, respectively, which account for 0.40% (95%CI: (0.11%, 0.69%) and 0.11% (95%CI: (0.07%, 0.15%) of the total annual Gross Domestic Product (GDP) of China in 2014.

Impact of Use of Chemical Transformation Modules in Calpuff on the Results of Air Dispersion Modelling

Abstract Assessment of the impact on air quality for combustion sources should be carried out using advanced modelling systems with chemical transformation modules taken into account, especially for the facilities characterized by significant emission of gaseous air pollutants (including SO2). This approach increases the reliability of the obtained evaluation results by modelling the formation of secondary inorganic aerosol (SIA) in the air which can substantially contribute to PM10. This paper assesses in this regard selected chemical transformation modules (MESOPUFF, RIVAD/ARM3, ISORROPIA/RIVAD) available in the CALPUFF model (v. 6.42) and its application in the atmospheric dispersion modelling of air emissions from a coal-fired large combustion plant (LCP) not equipped with a flue gas desulphurization (FGD) system. It has been proven that consideration an additional mechanism of secondary sulfate aerosol formation in aqueous phase in the ISORROPIA/RIVAD module (AQUA option) causes a significant increase in the annual average concentration of PM10 in the air compared to the other considered options, along with the calculation variant which excludes chemical transformation mechanisms. Type of the selected chemical transformation module has no significant effect on the results of modelled NO, NO2 and NOx concentrations in the air. However, it can lead to different SO2 results, especially for annual averaged, and in some points, for the hourly averaged concentrations.

Air Pollution and Potential Health Risk in Ostrava Region - a Review.

The aim of this review was to collect all available data about air pollution in Ostrava, which is one of the most polluted area in central Europe and to make a concise assessment of health risks resulting from historical exposures of air pollutants since the beginning of the monitoring, i.e. since 1970 to the present time. All available information sources (the Czech Hydrometeorological Institute, the Institute of Public Health in Ostrava or publications) were used. To evaluate the exposures both short-term (hourly and daily) data and long term (yearly) data during 45 years were analysed. For health risk assessment the relationship between exposure and biological effects of pollutants published by the WHO and the US EPA were employed. During the studied period annual average concentrations of PM10 ranged from 25 to 96 µg/m3; PM2.5 from 24 to 45 µg/m3; SO2 from 3.4 to 101.5 µg/m3; NO2 from 17.76 to 51.17 µg/m3; benzene from 0.24 to 9.2 µg/m3; benzo[a]pyrene from 2.1 to 14 ng/m3; arsenic from 1.2 to 9.5 ng/m3. Since the turn of the 80s and 90s of the 20th century trend of air pollutant concentrations has been decreasing until the turn of millennium, when it stopped, and it has been constant until present time. However, presented results demonstrate that the citizens of Ostrava have been exposed to relatively high concentrations of pollutants in comparison to other similar cities. The most significant pollutants contributing to health risks are airborne dust (PM10, PM2.5), benzene and benzo[a]pyrene. The long-term average health risk of PM10 has increased in case of postneonatal infant mortality up to 30%; prevalence of bronchitis in children up to 61%; and incidence of chronic bronchitis in adults up to 89%. The long-term average health risk of PM2.5 increased for all-cause mortality in persons aged 30+ years up to 22%; cardiopulmonary related mortality up to 25%; and lung cancer related mortality up to 39%. The highest carcinogenic risk is observed in benzo[a]pyrene, when the range of individual lifetime carcinogenic risk is up to 1.25*10-3. This assessment is valid according to the strict carcinogenic risk by the WHO, while the maximum carcinogenic risk according the US EPA is 7.2*10-5. A significant reduction of the pollutants' concentrations in Ostrava in the nineties of the last century does not mean a required improvement of outdoor air quality to the desired level. Persisting episodes with a very strong short-term increase of the concentration of PM10 and PM2.5, as well as long-term load of these substances on the population is very high. Health risks from such burdens are likely to lead to a higher mortality and morbidity especially from specific diseases.

CDH13 gene-by-PM10 interaction effect on lung function decline in Korean men

Lung function can be influenced by genetic factors, which may explain individual differences in susceptibility to the effects of air pollution. This study investigated whether the effect of particulate matter with an aerodynamic diameter ≤10 μm (PM10) on lung function is modified by Cadherin 13 (CDH13) genetic variants in Korean men. This study included a total of 1827 men who were recruited from two health check-up centers, and the annual average PM10 concentrations were used. A total of 200 single-nucleotide polymorphisms (SNPs) of the CDH13 gene were selected for this study.We found that a SNP in CHD13 intron, rs1862830, had the strongest associations with both forced expiratory volume in 1 s (FEV1) (pint = 1.90 × 10−4) and forced vital capacity (FVC) (pint = 1.88 × 10−3) by interacting with PM10 in a recessive model. A stratified association analysis according to this SNP showed that PM10 in the AG or GG genotype group was not significantly associated with either FEV1 or FVC, whereas in homozygous risk-allele carriers (AA), FEV1 and FVC decreased significantly (by 3.8% and 3.1%, respectively) per 10 μg/m3 of increase in PM10 concentration. This pattern was also reproducible in the independent subgroups that were classified according to recruitment site. The present study replicated the CDH13 gene-by-PM10 interaction effect on lung function at the gene level, revealing that a genetic variant of CDH13 modified the relationship between PM10 and lung function decline in Korean men.

Seasonal and spatial differences in source contributions to PM2.5 in Wuhan, China

Fine particle (PM2.5) samples were collected in 2011 and 2012 simultaneously at three sites in Wuhan in an industrial area (ID), downtown Wuhan (DT), and the Wuhan botanical gardens (BG). The annual average concentration of PM2.5 was highest in the industrial area at 180μgm−3 and lowest in the botanical gardens, with an average of 93μgm−3. The average downtown PM2.5 concentration was 113μgm−3. All sites had concentrations well above the World Health Organization (WHO) guidelines and the Chinese air quality standard. The concentration of major constituents of PM2.5 varied seasonally across all sites; specifically, sulfate, nitrate, and organic carbon varied most strongly during spring, followed by summer and fall. Organic carbon varied the most across sites for all seasons, which is attributable to large differences in local source emissions. The major primary sources contributing to OC were vehicle emissions (38.1±8.3%), coal combustion (7.0±6.2%), meat cooking (3.0±1.6%), and biomass burning (3.0±1.0%). All these sources had large seasonal variations across the three sites. Biomass burning had the largest impact at BG, mobile sources had the largest impact at DT, and coal combustion had the largest impact at ID. Mineral dust was a major contributor to PM2.5 (average 16.8±9.6μgm−3) and had very homogenous concentrations across the sites during springtime due to regional dust storms, but had much higher concentration at ID during the summer and fall. The results demonstrate the need for both regional and local air pollution control strategies to reduce air pollution in Wuhan. This research contributes to the field of particulate matter studies by providing information about seasonal and regional fluctuations in PM2.5 in large urban areas, which helps advance understanding of the sources responsible for urban haze.

Association between exposure to fine particulate matter and adverse pregnancy outcomes in Kaunas

Introduction: Epidemiological studies have suggested that maternal exposure to particulate matter during pregnancy may be associated with adverse health outcomes including low birth weight. However, the findings from these studies have been inconsistent. We examined the effect of long-term exposure to PM2.5 on birth weight by using a linear spline function. Methods: The prospective cohort study included 3292 pregnant women living in Kaunas city, Lithuania between 2007 and 2008. The primary outcomes of the study were low birth weight (LBW < 2500 g) and term low birth weight (TLBW < 2500 g; ≥ 37 weeks gestation). The annual average concentration of PM2.5 at the participants’ home addresses was estimated using land use regression (LUR) model which was developed from the data from air pollution measurements and geographic information systems (GIS). To detect potential confounding variables odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. We used a two-piece linear spline function and multivariate logistic regression analysis to evaluate the association between exposure to PM2.5 and the risk of LBW and TLBW controlling for confounding variables effect. Results: The study results showed that the risk of LBW and TLBW increased statistically significantly with increasing exposure to PM2.5. After adjustment for confounding variables the ORs for LBW among women exposed to the third and fourth quartiles of PM2.5 exposure were 1.27 (95 % CI 0.84–1.93) and 1.69 (95 % CI 1.14–2.50), compared with PM2.5 concentrations below the median. The risk for TLBW among women exposed to the third and fourth quartiles of PM2.5 exposure were 1.78 (95 % CI 0.85–3.73) and 2.89 (95 % CI 1.50–5.60), compared with PM2.5 concentrations below the median. Conclusions: Our study provided evidence that maternal exposure to PM2.5 may adversely affect the birth weight; a non-linear association between exposure to PM2.5 and LBW and TLBW was detected.

Long-term exposure to particulate matter air pollution and leukocyte count in Taiwanese adults: a repeated-measures analysis

Introduction Particulate matter (PM) air pollution has been associated with increased cardiovascular morbidity and mortality, and systemic inflammation might be the intermediate step. We investigated the associations between long-term exposure to PM with an aerodynamic diameter ≤ 2.5 μm (PM2.5) and peripheral leukocyte count, a marker of systemic inflammation in a large cohort. Methods This cohort consisted of Taiwanese who participated in a standard medical screening program between 2000 and 2014 with repeated measurements of leukocyte count. Information on a wide range of potential confounders was collected during medical examination. The participants' residential addresses were geo-coded into latitude and longitude data and then the ambient PM2.5 concentrations at the addresses 1 x 1 kilometer grid were estimated by a remote-sensing algorithm based on the US National Aeronautics and Space Administration satellite data. We developed mixed effects models to investigate the associations between PM2.5 exposure and leukocyte count with a person-level intercept to account for within-person clustering effects, and with adjustment for potential confounders. Results A total of 380,632 participants (48.6% men) with 841,881 observations were included in data analysis. Annual average concentration of PM2.5 was positively associated with leukocyte count. Per 10 μg/m3 increment in PM2.5 level was associated with 0.36% increase in leukocyte count [95% confidence interval (CI): 0.33%, 0.40%]. After full adjustment for age, sex, educational level, body mass index, morbidities (hypertension, diabetes and hyperlipidemia) and lifestyle factors (smoking, alcohol drinking and exercise), the effects were attenuated but remained statistically significant (0.25% per 10 μg/m3 PM2.5 increment, 95%CI: 0.22%, 0.28%). Conclusions Our results suggest that long-term exposure to PM2.5 was associated with increased peripheral leukocyte count, indicating an activated systemic inflammation status.

The association of long term exposure to low concentrations of fine particulates and nitrogen oxides and risk of all-cause mortality and stroke-specific mortality and morbidity.

Introduction: There is increasing evidence of the effects of long term exposure to air pollutants and mortality, especially related to cardiovascular outcomes. We investigated the association between long term exposure to low concentrations of fine particulates (PM2.5) and nitrogen oxides (NO2 and NOx) and all-cause mortality as well as stroke-specific mortality and morbidity. Method: We used data from the Health in Men Study (HIMS), a cohort of12,201 elderly men aged 65 years and above, who lived in Perth Metropolitan Area and were followed from 1996 to 2012. Estimation of long term exposure to PM2.5, NO2 and NOx at each participant’s home address was based on land use regression models. The hazard ratios (HR)s and 95% confidence intervals (CI) for the impact of the pollutants and health outcomes were estimated by Cox proportional hazard regression models. Results: The annual average concentrations of PM2.5 was 4.7µg/m3, NO2 11.3µg/m3 and NOx 23.4 µg/m3. There were 6,344 deaths from all causes, 405 deaths from stroke, and 2134 of study participants developed stroke during the follow up. The preliminary analyses indicate the following results: for all causes mortality, the hazard ratio associated with a 5 µg/m3 increase in PM2.5 exposure was 1.05 (95%CI 0.99 – 1.11). Similar associations were found for NO2 and NOx with HR of 1.05 (95%CI 1.02 – 1.09) and 1.03(95%CI 1.01 – 1.04), respectively. The hazard ratio for stroke mortality associated with every 5 µg/m3 increase in the concentrations of PM2.5 was HR:1.05 (95%CI 0.95 – 1.16), for NO2 HR:1.01 (95%CI 0.96 – 1.07) and for NOx HR:1.01 (95%CI 0.98 – 1.03). Similar associations were observed between stroke incidence with all air pollutants. Conclusions: Long term exposure to PM2.5, NO2, and NOx may increase the risk of all-cause mortality and stroke-causes mortality and morbidity in Perth even at low concentrations.