Air Pollution Conditions Research Articles

Personal exposure measurements of school-children to fine particulate matter (PM2.5) in winter of 2013, Shanghai, China.

ObjectiveThe aim of this study was to perform an exposure assessment of PM2.5 (particulate matter less than 2.5μm in aerodynamic diameter) among children and to explore the potential sources of exposure from both indoor and outdoor environments.MethodsIn terms of real-time exposure measurements of PM2.5, we collected data from 57 children aged 8–12 years (9.64 ± 0.93 years) in two schools in Shanghai, China. Simultaneously, questionnaire surveys and time-activity diaries were used to estimate the environment at home and daily time-activity patterns in order to estimate the exposure dose of PM2.5 in these children. Principle component regression analysis was used to explore the influence of potential sources of PM2.5 exposure.ResultsAll the median personal exposure and microenvironment PM2.5 concentrations greatly exceeded the daily 24-h PM2.5 Ambient Air Quality Standards of China, the USA, and the World Health Organization (WHO). The median Etotal (the sum of the PM2.5 exposure levels in different microenvironment and fractional time) of all students was 3014.13 (μg.h)/m3. The concentration of time-weighted average (TWA) exposure of all students was 137.01 μg/m3. The median TWA exposure level during the on-campus period (135.81 μg/m3) was significantly higher than the off-campus period (115.50 μg/m3, P = 0.013 < 0.05). Besides ambient air pollution and meteorological conditions, storey height of the classroom and mode of transportation to school were significantly correlated with children’s daily PM2.5 exposure.ConclusionsChildren in the two selected schools were exposed to high concentrations of PM2.5 in winter of 2013 in Shanghai. Their personal PM2.5 exposure was mainly associated with ambient air conditions, storey height of the classroom, and children’s transportation mode to school.

Simulating global horizontal irradiance in the Arabian Peninsula: Sensitivity to explicit treatment of aerosols

Global horizontal irradiance (GHI) is simulated using a three-dimensional atmospheric meteorology-chemistry model and a triple-nesting configuration over the Middle East with a focus on the hot desert climate of Qatar. The model performance was assessed with measurement data of solar radiation from a ground monitoring station in Doha (Qatar) collected over a three-month period, of representative and distinct meteorological regimes. We have examined the ability of the model to reproduce GHI values under two different shortwave downward radiation parameterizations, and assessed the sensitivity of our results to the presence of aerosols. The introduction of an advanced treatment of aerosols greatly improves the model performance in predicting GHI. Explicitly including aerosol processes and its emissions in the model significantly reduces the relative root mean square error for GHI from 25% to 13% in May and from 20% to 12% in August. A significant improvement of the systematic bias was achieved (from up to 30% to approximately 2%) when aerosols are fully considered during all three seasons. The RRTM (Rapid Radiative Transfer Model) shortwave radiation scheme performs somewhat better than the Goddard scheme both with and without aerosols. This work suggests that GHI predictions in regions that experience high aerosol loadings can benefit significantly from a detailed and explicit treatment of aerosols and their physicochemical processes. This offers a novel approach to better manage the fluctuating nature of solar radiation originating from variable weather and air pollution conditions.

Simulation and Analysis of Polluted Days in Tehran

The air pollution is a process which partially depends on the atmospheric conditions. The subject of the present research is analyzing the distribution of the pollutant “CO” in Tehran considering the effects of different wind patterns in cold seasons of year. The main objective of this research is to identify Tehran’s thermo-dynamical synoptic systems resulting in intensification of atmospheric stable condition, and to analyze the pollutant movements by wind. 14 samples of severe and widespread polluted days in the cold period (October to April) of 2002–2012 are selected and statistical, synoptic, and simulation methods are applied to investigate the air pollution in Tehran. According to the results, generally, concentrations of CO pollutant have reduced during the under studied decade. In addition, the results showed that the air pollution of Tehran follows a high-pressure system pattern which is located in the mid-levels of the atmosphere. In severe air pollution conditions, Tehran is located in the axis of a ridge which leads to the air subsidence due to the convergence of upper air currents. According to the analysis of upper air conditions, there was a column of steady air (about 1.5 km above the sea level) in which the density of pollutants increased and all indices confirmed stability conditions during the polluted days. The TAPM model is applied to simulate the wind pattern of Tehran. Four domains with horizontal resolutions of 5, 3, 2, and 1 km are chosen. The results of simulation show that winds in Tehran have different patterns during 24 h and local parameters such as slope directions can affect the air pollution concentration in stable synoptic conditions. In addition, Anabatic and Katabatic winds are frequent in Tehran due to its location in a valley in Alborz southern slopes and winds are considerably affected by the topography of the city. According to the results in the first hours of the day, calm winds are frequent and concentration of the pollutants is resulted from the limitation of boundary layer which caused the accumulation and intensification of air pollution in Tehran during the cold seasons.

Privacy-Preserving Top-&lt;inline-formula&gt; &lt;tex-math notation="LaTeX"&gt;$k$ &lt;/tex-math&gt; &lt;/inline-formula&gt; Route Computation in Indoor Environments

Most of us live our daily lives in various types of indoor environments. With the rapidly increasing air pollution and abnormal weather conditions occurring all over the world, the importance of indoor space is expected to increase in the future. As the importance of indoor spaces has increased, there have been extensive efforts to understand the indoor behavior patterns of individuals by collecting and analyzing their indoor positioning data. However, indiscriminate collection of indoor location information may raise significant privacy issues, because it is possible to infer sensitive information by analyzing their indoor location data. Thus, there is a need to develop a technology capable of: 1) collecting individuals’ indoor positioning data while not violating privacy requirements and 2) analyzing their movement patterns, based on the indoor positioning data set collected in a privacy-preserving manner. Recently, there has been a growing interest in local difference privacy (LDP) that can protect individual privacy in the process of data collection. The main concept of LDP is adding carefully designed noise to sensitive data at the data contributor’s side and directly sending the noisy data to a data collector, guaranteeing that the original data are not exposed to the outside. In this paper, we first develop a method to collect individuals’ indoor positioning information by leveraging LDP, and then, we introduce an effective approach to compute top- $k$ routes between two points in indoor environments by leveraging the indoor positioning data sets collected in an LDP manner. Experimental results show that the proposed approach well exploits the indoor positioning data collected in an LDP-compliant manner, and a good estimation of top- $k$ routes can be achieved with the proposed method and a large data set.

Air Pollution and Specific Meteorological Conditions at the Adjacent Areas of Sea Ports

Abstract Meteorological conditions and phenomena in coastal areas show specific peculiarities caused, or significantly affected, by sharp changes in heat, moisture, and momentum transfer due to the contrast in land-sea underlying surfaces. These conditions may be conducive to trap and retain pollutants in the lowest layer of the atmosphere or to assist in its cleaning. Sea transport is the cheapest one and ports are portals for world trade, often being a basic prerequisite for the development of various economic sectors in the coastal regions. Shipping vessels engines run on heavy fuel oil which has a high polluting impact, as the SO2 content of heavy fuel oil is 2700 times higher than in road fuel. Some aspects of the role of meteorological conditions on the dispersion of pollutants and the air quality in the biggest Bulgarian coastal cities of Varna and Burgas are subject of discussion in the present paper.

The position paper of the Polish Society of Allergology on climate changes, natural disasters and allergy and asthma.

The observed global climate change is an indisputable cause of the increased frequency of extreme weather events and related natural disasters. This phenomenon is observed all over the world including Poland. Moreover, Polish citizens as tourists are also exposed to climate phenomena that do not occur in our climate zone. Extreme weather events and related disasters can have a significant impact on people with allergic diseases, including asthma. These effects may be associated with the exposure to air pollution, allergens, and specific microclimate conditions. Under the auspices of the Polish Society of Allergology, experts in the field of environmental allergy prepared a statement on climate changes, natural disasters and allergy and asthma to reduce the risk of adverse health events provoked by climate and weather factors. The guidelines contain the description of the factors related to climate changes and natural disasters affecting the course of allergic diseases, the specific microclimate conditions and the recommendations of the Polish Society of Allergology for vulnerable population, patients suffering from asthma and allergy diseases, allergologists and authorities in the event of climate and weather hazards.

Short-Term Exposure to Haze Air Pollution Induces Acute Airway Inflammation and Lung Function Reduction in Healthy Adult Subjects

Haze air pollution with high levels of PM has frequently took place in many areas of China in the past few years. However, the health effect of shirt-term exposure to haze air pollution has not been thoroughly characterized. This study aimed to determine the acute effect of haze exposure on respiratory system of healthy adult subjects, specifically on airways and lung function. Thirty healthy adult subjects were recruited and airway inflammation and lung function alterations examined under control and haze air pollution (157.33 μg/m for mean concentration of PM ) conditions, respectively. Airway inflammation was assessed by sputum induction while lung function was measured using spirometry. It was shown that 24-h exposure to haze air pollution could increase the levels of inflammatory mediators including interleukin-6 (IL-6), IL-8, and tumor necrotic factor-α (TNF-α), as well as the percentages of eosinophils, neutrophils, and lymphocytes in the sputum (<0.05). In contrast, the proportion of macrophages in the sputum from haze-exposed subjects decreased significantly (<0.05). In addition, short-term exposure to haze could decrease forced vital capacity (FVC), forced expiratory volume in the first second (FEV ), vital capacity (VC), and maximum voluntary ventilation (MVV), but not FEV1/FVC. In summary, short-term exposure of healthy adult subjects to haze air pollution induces airway inflammation and lung function impairment.

Characterizing of Air Pollution in Tehran: Comparison of Two Air Quality Indices

Multi-pollutant air pollution dramatically occurs in wide range of regions across Tehran. Air quality index (AQI) is applied worldwide to inform the public about levels of air pollution and related to health risks. Assessing air pollution, and transferring information about its possible adverse health effects, may encourage population and policy makers to reduce activities that increase pollution levels. In this study the Air quality index (AQI), Aggregate Air quality index (AAQI), and a relative index of variability (VR) were obtained for the data in order to better investigate air pollution conditions for the whole areas of a city of Tehran, aim at warning the people of short-term health impact. The proposed index of variability does add precious information to the aggregate AQI, as it can demonstrate whether the value assumed by the AQI is influenced by one or more pollutants. The two indices are together used on simulated data and consider different possible scenarios. In addition, Applications to real air pollution data are reported. Before applying the two indices, the effects of different standardizations on data are evaluated from a theoretical point of view.

Ambient air pollution, smog episodes and mortality in Jinan, China

We aimed to assess the acute effects of ambient air pollution and weather conditions on mortality in the context of Chinese smog episodes. A total of 209,321 deaths were recorded in Jinan, a large city in eastern China, during 2011–15. The mean concentrations of daily particulate matter ≤10 μm (PM10), fine particulate matter (PM2.5), sulfur dioxide (SO2) and nitrogen dioxide (NO2) were 169 μg/m3, 100 μg/m3, 77 μg/m3, and 54 μg/m3, respectively. Increases of 10 μg/m3 in PM10, PM2.5, SO2 and NO2 were associated with 1.11% (95% CI 0.96–1.26%), 0.71% (95% CI 0.60–0.82%), 1.69% (95% CI 1.56–1.83%), and 3.12% (95% CI 2.72–3.53%) increases in daily non-accidental mortality rates, respectively. Moreover, the risk estimates for these 4 pollutants were higher in association with respiratory and cardiovascular mortality. The effects of all the evaluated pollutants on mortality were greater in winter than in summer. Smog episodes were associated with a 5.87% (95% CI 0.16–11.58%) increase in the rate of overall mortality. This study highlights the effect of exposure to air pollution on the rate of mortality in China.

Changes in domestic heating fuel use in Greece: effects on atmospheric chemistry and radiation

Abstract. For the past 8 years, Greece has been experiencing a major financial crisis which, among other side effects, has led to a shift in the fuel used for residential heating from fossil fuel towards biofuels, primarily wood. This study simulates the fate of the residential wood burning aerosol plume (RWB smog) and the implications on atmospheric chemistry and radiation, with the support of detailed aerosol characterization from measurements during the winter of 2013–2014 in Athens. The applied model system (TNO-MACC_II emissions and COSMO-ART model) and configuration used reproduces the measured frequent nighttime aerosol spikes (hourly PM10 &gt; 75 µg m−3) and their chemical profile (carbonaceous components and ratios). Updated temporal and chemical RWB emission profiles, derived from measurements, were used, while the level of the model performance was tested for different heating demand (HD) conditions, resulting in better agreement with measurements for Tmin &lt; 9 °C. Half of the aerosol mass over the Athens basin is organic in the submicron range, of which 80 % corresponds to RWB (average values during the smog period). Although organic particles are important light scatterers, the direct radiative cooling of the aerosol plume during wintertime is found low (monthly average forcing of –0.4 W m−2 at the surface), followed by a minor feedback to the concentration levels of aerosol species. The low radiative cooling of a period with such intense air pollution conditions is attributed to the timing of the smog plume appearance, both directly (longwave radiation increases during nighttime) and indirectly (the mild effect of the residual plume on solar radiation during the next day, due to removal and dispersion processes).

The relationship between airborne fine particle matter and emergency ambulance dispatches in a southwestern city in Chengdu, China

High levels of fine particulate matter (PM2.5) are known to cause adverse effects to human health. The goal of this study was to estimate the acute health effects of short-term exposure to ambient PM2.5 by analyzing cause-specific emergency ambulance dispatches as the endpoint in Chengdu, a city in Sichuan Province in southwest China. The ambient PM2.5 concentration of Chengdu reached 63 μg/m3 in 2015. Data related to the causes of specific emergency ambulance dispatches, air pollution, and meteorological conditions were collected from 2013 to 2015 (1095 days). A generalized additive model (GAM) was constructed to control the confounding conditions and to estimate the effects of PM2.5 on human health conditions. Emergency ambulance dispatches for all causes with (RR for lag0 = 1.0010, 95%CI: 1.0002, 1.0019) or without injuries (RR for lag0 = 1.0012, 95%CI: 1.0002, 1.0022), respiratory diseases (RR for lag0 = 1.0051, 95%CI: 1.0012, 1.0089), and cardiovascular diseases (RR for lag0 = 1.0041, 95%CI: 1.0009, 1.0074) were associated with ambient PM2.5 concentrations in Chengdu. In addition, the effects of PM2.5 were not confounded by ozone.

Air stagnation in China (1985–2014): climatological mean features and trends

Abstract. Air stagnation is an important meteorological measure of unfavorable air pollution conditions, but little is known about it in China. We conducted a comprehensive investigation of air stagnation in China from January 1985 to December 2014 based on sounding and surface observations from 81 stations. The stagnation criteria were revised to account for the large topographical diversity in the country. It is found that the annual mean of air stagnation occurrences is closely related to general topography and climate features. Two basins in the northwest and southwest of China, the Tarim and Sichuan basins, exhibit the most frequent stagnation occurrence (50 % of days per year), whereas two plateaus (the Qinghai–Tibet Plateau and the Inner Mongolian plateau) and the eastern coastal areas experience the least (20 % of days per year). Over the whole country, air stagnation is at a maximum in summer and a minimum in winter, except for Urumchi, a major city in northwestern China where stagnation maintains a rather constant value year round with a minimum in spring. There is a nationwide positive trend in stagnation occurrence during 1985–2014, with the strongest increasing centers over Shandong Peninsula in eastern China and southern Shaanxi in central China. Changes in air stagnation occurrences are dependent on three components (upper- and lower-air winds and precipitation-free days). This shows that the behavior of upper-air wind speeds is the main driver of the spatial distribution and trends in air stagnation, followed by near-surface winds and dry days, which contribute the least.

Investigating the link between $$\hbox {PM}_{2.5}$$ PM 2.5 and atmospheric profile variables via penalized functional quantile regression

Fine particulate matter (\(\hbox {PM}_{2.5}\)) events negatively affect the health of numerous persons globally each year. Previous works have described the association between air pollution and surface-level meteorological conditions; however, there has been less focus on the task of linking air pollution events with meteorological conditions at higher levels of the atmosphere. Working within the functional data framework, we develop a penalized functional quantile regression (PFQR) procedure to model conditional quantiles of a continuous response based on a functional covariate, with the ability to penalize selected derivatives of the estimated coefficient function. Our aim is to investigate the relationship between atmospheric profile variables (APVs), assumed to be functional, and key quantiles of the conditional distribution of surface-level \(\hbox {PM}_{2.5}\). Via a simulation study, we find that the performance of our PFQR procedure compares favorably to other related approaches. We conclude with an analysis of \(\hbox {PM}_{2.5}\) data at two Southeastern US locations, Columbia, SC and Tampa, FL, where we estimate the coefficient functions for the APVs corresponding to both ‘typical’ and ‘high’ \(\hbox {PM}_{2.5}\) events. As we believe that the true coefficient functions are smooth and may be exactly zero over subsets of their domains, we impose penalties on the 0th and 2nd derivatives. Our analysis indicates that the corresponding atmospheric conditions differ between the two locations, and that the conditions differ seasonally within location.

High resolution estimates of the corrosion risk for cultural heritage in Italy

Air pollution plays a pivotal role in the deterioration of many materials used in buildings and cultural monuments causing an inestimable damage. This study aims to estimate the impacts of air pollution (SO2, HNO3, O3, PM10) and meteorological conditions (temperature, precipitation, relative humidity) on limestone, copper and bronze based on high resolution air quality data-base produced with AMS-MINNI modelling system over the Italian territory over the time period 2003–2010. A comparison between high resolution data (AMS-MINNI grid, 4 × 4 km) and low resolution data (EMEP grid, 50 × 50 km) has been performed. Our results pointed out that the corrosion levels for limestone, copper and bronze are decreased in Italy from 2003 to 2010 in relation to decrease of pollutant concentrations. However, some problem related to air pollution persists especially in Northern and Southern Italy. In particular, PM10 and HNO3 are considered the main responsible for limestone corrosion. Moreover, the high resolution data (AMS-MINNI) allowed the identification of risk areas that are not visible with the low resolution data (EMEP modelling system) in all considered years and, especially, in the limestone case. Consequently, high resolution air quality simulations are suitable to provide concrete benefits in providing information for national effective policy against corrosion risk for cultural heritage, also in the context of climate changes that are affecting strongly Mediterranean basin.

Physical Activity and Sport Competitions Under Severe Air Pollution Conditions

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Air pollution characteristics and their relation to meteorological conditions during 2014–2015 in major Chinese cities

In January 2013, the real-time hourly average concentrations of six pollutants (CO, NO2, O3, PM10, PM2.5 and SO2) based on data from air quality monitoring stations in major Chinese cities were released to the public. That report provided a good opportunity to publicise nationwide temporal and spatial pollution characteristics. Although several studies systematically investigated the temporal and spatial trends of pollutant concentrations, the relation between air pollution and multi-scale meteorological conditions and their spatial variations on a nationwide scale remain unclear. This study analysed the air pollution characteristics and their relation to multi-scale meteorological conditions during 2014–2015 in 31 provincial capital cities in China. The annual average concentrations of six pollutants for 31 provincial capital cities were 1.2 mg m−3, 42.4 μg m−3, 49.0 μg m−3, 109.8 μg m−3, 63.7 μg m−3, and 32.6 μg m−3 in 2014. The annual average concentrations decreased 5.3%, 4.9%, 11.4%, 12.0% and 21.5% for CO, NO2, PM10, PM2.5 and SO2, respectively, but increased 7.4% for O3 in 2015. The highest rate of a major pollutant over China was PM2.5 followed by PM10, O3, NO2, SO2 and CO. Meteorological conditions were the primary factor determining day-to-day variations in pollutant concentrations, explaining more than 70% of the variance of daily average pollutant concentrations over China. Meteorological conditions in 2015 were more adverse for pollutant dispersion than in 2014, indicating that the improvement in air quality was caused by emission controls.

Influence of exposure to coarse, fine and ultrafine urban particulate matter and their biological constituents on neural biomarkers in a randomized controlled crossover study

BackgroundEpidemiological studies have reported associations between air pollution and neuro-psychological conditions. Biological mechanisms behind these findings are still not clear. ObjectivesWe examined changes in blood and urinary neural biomarkers following exposure to concentrated ambient coarse, fine and ultrafine particles. MethodsFifty healthy non-smoking volunteers, mean age 28years, were exposed to coarse (2.5–10μm, mean 213μg/m3) and fine (0.15–2.5μm, mean 238μg/m3) concentrated ambient particles (CAPs), and filtered ambient and/or medical air. Twenty-five participants were exposed to ultrafine CAP (mean size 59.6nm, range 47.0–69.8nm), mean (136μg/m3) and filtered medical air. Exposures lasted 130min, separated by ≥2weeks, and the biological constituents endotoxin and β-1,3-d-glucan of each particle size fraction were measured. Blood and urine samples were collected pre-exposure, and 1-hour and 21-hour post-exposure to determine neural biomarker levels. Mixed-model regressions assessed associations between exposures and changes in biomarker levels. ResultsResults were expressed as percent change from daily pre-exposure biomarker levels. Exposure to coarse CAP was significantly associated with increased urinary levels of the stress-related biomarkers vanillylmandelic acid (VMA) and cortisol when compared with exposure to filtered medical air [20% (95% confidence interval: 1.0%, 38%) and 64% (0.2%, 127%), respectively] 21hours post-exposure. However exposure to coarse CAP was significantly associated with decreases in blood cortisol [−26.0% (−42.4%, −9.6%) and −22.4% (−43.7%, −1.1%) at 1h and 21h post-exposure, respectively]. Biological molecules present in coarse CAP were significantly associated with blood biomarkers indicative of blood brain barrier integrity. Endotoxin content was significantly associated with increased blood ubiquitin C-terminal hydrolase L1 [UCHL1, 11% (5.3%, 16%) per ln(ng/m3+1)] 1-hour post-exposure, while β-1,3-d-glucan was significantly associated with increased blood S100B [6.3% (3.2%, 9.4%) per ln(ng/m3+1)], as well as UCHL1 [3.1% (0.4%, 5.9%) per ln(ng/m3+1)], one-hour post-exposure. Fine CAP was marginally associated with increased blood UCHL1 when compared with exposure to filtered medical air [17.7% (−1.7%, 37.2%), p=0.07] 21hours post-exposure. Ultrafine CAP was not significantly associated with changes in any blood and urinary neural biomarkers examined. ConclusionAmbient coarse particulate matter and its biological constituents may influence neural biomarker levels that reflect perturbations of blood-brain barrier integrity and systemic stress response.

Influence of coastal wind on surface ozone and nitrogen oxides in suburban Shanghai

Surface ozone, NO, NO2, and NOx were measured at a coastal site (Shihua) and a nearby inland site (Zhujing) in suburban Shanghai for the whole year of 2009. More days with ozone pollution in a longer time range were observed at the coastal site than the inland site. The diurnal variations of NOx concentrations were obviously higher at Zhujing station, while those of ozone concentrations were higher at Shihua station, indicating their different air pollution conditions. Coastal wind has significant influence on the levels and characteristics of the air pollutants. The ozone concentrations during maritime winds (MW) were much higher than those during continental winds (CW) at each of the site, while the NO and NO2 concentrations were both opposite. The ozone concentrations at Shihua station were much higher than those at Zhujing station, while the NO and NO2 concentrations were both opposite. The ozone concentrations at both of the two sites showed a distinct “weekend effects” and “weekdays effects” patterns during CW and MW, respectively. Correlation analysis of the pollutants showed that, the compounds during MW were more age than those during CW, and the compounds at Shihua were more age than those at Zhujing. The air pollutions at both of the two sites are mainly associated with the pollutants emitted in this region instead of long range transport.

The Influence of Air Pollution and Weather Conditions on Traffic Crashes and Traffic-Related Mortality in Ahvaz, Iran

The Influence of Air Pollution and Weather Conditions on Traffic Crashes and Traffic-Related Mortality in Ahvaz, Iran

Impacts of air pollution on cultural heritage corrosion at European level: What has been achieved and what are the future scenarios

The interaction of pollutants with Cultural Heritage materials leads to artworks and materials degradation and loss, causing an unpriceless damage. This works aims to estimate the impacts of air pollution and meteorological conditions on limestone, copper and bronze and represents the European risk assessment for corrosion of Cultural Heritage materials. The measures and policies for atmospheric pollution reduction have cut off the SO2 concentration and consequently its impact on materials is drastically reduced. Indeed, in 1980 the number of UNESCO sites in danger was extremely high (94% for limestone, 54% for copper and 1% for bronze) while in 2010 these sites did not exceed the tolerable value of surface recession and corrosion. However, some problem related to air pollution persists. In particular, Random Forest Analysis (RFA), highlights PM10 as the main responsible for materials corrosion, in 2010. Two scenarios in 2030 have been tested, highlighting that the corrosion levels of limestone, copper and bronze exceed the tolerable limits only in the Balkan area and Turkey. Our results show the importance in the air quality modelling as a powerful tool for the UNESCO sites conservation.