Air Pollution Research Research Articles

CHAIR-consortium: A collaboration for air pollution research across India

Ambient air pollution levels in India are among the highest in the world and contribute to climate change and poor health. Despite extreme levels of air pollution and increased frequency and intensity of heat waves in India, current Indian public policy to reduce emissions has been inadequate and lacked a coordinated and sustained effort. Planned coal power plants will additionally contribute to both more CO2 and air pollution emissions. Moreover, lack of monitoring in rural areas has contributed to a belief that air pollution is only an urban problem. To address this we have developed an exposure assessment methodology employing machine-learning methods and multiple data sources including monitoring data, satellite data, meteorology and land-use data to make reliable high resolution predictions of particulate matter <2.5 µm in diameter (PM2.5) and temperature in areas with sparse monitoring. We will develop a nation-wide exposure model for daily ambient PM2.5 and ambient temperature from 2008-2020 at a spatial resolution of 1 km x 1 km and locally at 200 m x 200 m in India. Our aim is to link our national estimates of PM2.5 and temperature to health data to quantify the associations between PM2.5 and ambient temperature, independently and jointly on major public health endpoints. Our specific intention is to make the exposure model an open resource to accelerate environmental epidemiology and build capacity around the many existing health studies in India to which the exposure model can be applied. We will develop an online interactive environmental database and a strategy for stakeholder communication to significantly facilitate decision-making and increase public awareness and engagement. Successful fulfillment of our aims in India will significantly contribute to sustainable development benefitting not only the very large Indian population but also the global community.

Insight into monsoon for shaping the air quality of Islamabad, Pakistan: Comparing the magnitude of health risk associated with PM10 and PM2.5 exposure

ABSTRACT Monsoon plays a determinant role in defining the air quality of many Asian countries. Filter-based 24 h ambient PM10 and PM2.5 sampling was performed by using two paralleled medium volume air samplers during pre-and post-monsoon periods. A negligible change in PM2.5 mass concentration from 45.77 to 44.46 µg/m3 compared to PM10 from 74.34 to 142.49 µg/m3 was observed after the monsoon season. The air quality index (AQI) results showed that the air quality of the city retained from good to slightly polluted in both periods, where PM2.5 remained as the main detrimental to air quality in 95% of the total days. The NOAA HYSPLIT model analysis and wind rose patterns showed air trajectories, especially in post-monsoon originated from relatively polluted areas transported higher PM10. Meteorological attributes indicated a more conducive atmospheric condition for secondary pollution in the pre-monsoon. Evidence showed post-monsoon as a more polluted period, compared to the pre-monsoon and would pose an extra 1.07 × 10−3 lifetime risk to the local population. Similarly, a higher level of PM10 in the post-monsoon caused 43% more premature mortality and 41% more deaths from all-cause mortality compare to the pre-monsoon period, respectively. Implications: Pakistan is an under-developing country where pollution monitoring studies are decidedly limited. Notably, studies, concise PM2.5 and health assessment are deficient. The present study may contribute to evaluating the air quality in special events such as monsoon and can also provide scientific and technical support for subsequent air pollution research. Moreover, the results help to develop adequate prevention and pollution control strategies and offer policy suggestions for monsoon observing countries in general and in particular, in Islamabad, Pakistan. These findings provide essential arguments in favor of educating people and raising awareness about the detrimental health effects of air pollution. Improving the quality of life of people with cardiovascular and respiratory disorders requires an immediate and substantial reduction of air pollution.

Engaging Citizens in Air Pollution Research: Investigating the Built Environment and Indoor Air Quality and Its Impact on Quality of Life

Abstract There is evidence that when people are exposed to sociobehavorial and socioeconomic disadvantage they become more susceptible to the impacts of poor environmental quality and experience ex...

The exposome and meet-in-the-middle as tools in addressing open questions in air pollution research

Abstract Ambient particulate matter is the environmental factor with the highest contribution to global disease burden and mortality. Open questions remain regarding causality at low doses and the effects of specific pollutants. Establishing causality in regards to air pollution is methodologically challenging, affecting the establishment of regulatory policies. In an effort to address this problem, we suggest combining the concept of the exposome with the Meet-in-the-Middle approach (MITM). This approach consists of measuring molecular fingerprints and relating them retrospectively to measurements of external exposure and prospectively to a health outcome. Markers robustly associated with both ends of the exposure-to-disease continuum, validate a causal hypothesis5. In the context of carcinogenesis, this approach allows establishing the relationship between the middle-to-outcome nature of the hallmarks of cancer with the bottom-to-middle approaches of the key characteristics of carcinogens. We recently demonstrated proof of principle of this approach, by investigating the temporal sequence of hallmarks of cancer from the point of view of pathological specimens of cancer (branched mutational spectra), and then by considering the key characteristics of the carcinogen, benzo(a)pyrene. The main cancer pathways affected follow a generally common sequence: resisting cell death, insensitivity to anti-growth signals, sustained proliferation (almost simultaneous), deregulated energetics, replicative immortality, and activation of invasion and metastasis. Angiogenesis and avoiding immune destruction display a varying position in the above sequence. At the same time, “key characteristics” of BaP were found associated with most hallmarks of cancer, supporting its carcinogenicity. A MITM approach, using exposomic evidence, is a promising approach that can successfully address causality concerns in regards to air-pollution toxicology and the need for regulatory policies. Key messages Investigation of tumour mutational spectra and of the mechanisms of action of a carcinogen, reveals an overlap between the hallmarks of cancer and the key characteristics of the carcinogen. This investigation provides proof of principle that the exposome/meet-in-the-middle approach can address concerns in air-pollution toxicology and provide evidence to support regulatory policies.

In Memoriam: Kirk R. Smith.

In Memoriam: Kirk R. Smith.

Through Internet and Friends: Translation of Air Pollution Research in Malmö Municipality, Sweden.

Air pollution is estimated to cause more than 7000 deaths annually in Sweden alone. To reduce the impact of air pollution and to plan and build sustainable cities, it is vital that research is translated into efficient decisions and practice. However, how do civil servants in a municipality access research results? How do they normally find relevant information, and what obstacles are there to accessing and applying research results? As part of the collaborative and transdisciplinary research project Air Pollution Research in Local Environmental Planning (ARIEL), these questions were explored through interviews and seminars with civil servants within the Malmö Municipality Environmental Office. We found that the civil servants generally have proficiency in processing research results, but often do not use such results as part of their everyday decision making and practices. Instead, the data and measurements used are mostly produced case-by-case within the municipal sector itself. Information about best practices is also collected via a number of knowledge access practices, involving the Internet or social networks within other municipalities. Lack of time, paywalls, and the insufficient applicability of research hinder the dissemination of up-to-date results. This slows down the process whereby research, funded by tax-money, can be put to best practice in the effort to create healthy and sustainable cities.

Evaluation and scientometric analysis of researches on air pollution in developing countries from 1952 to 2018

Many scholars have worked to solve the widespread problems associated with air pollution especially in developing countries. So, there is a huge bulk of research output in this field that should be classified to determine the next steps and finding out research gaps. Hence, in this study, the scientometric approach was performed by CiteSpace V to draw the trends and signify issues in the research area. Based on the search in ISI Web of Science database, 25,363 documents were retrieved for air pollution in developing countries. The documents were analyzed for co-authorship, countries collaboration, ISI Web of Science categories co-occurrence, keyword co-occurrence, and institutional collaboration. The data showed the published studies had an upward trend over the years. By considering the number of citations, China plays an important role in air pollution research in developing countries, and the USA is the top country with the potential to change the structure of the network. Along with the developing countries, developed countries have also played a serious role in advancing research in this field. The trend of the studies has shown that research trends in early years tend to pure environmental studies, and in recent years, it has shifted to areas like monitoring, management, and biodiversity conservation. Keyword co-occurrence showed sulfur dioxide with a duration of 22 years is one of the most important issues in studies of air pollution in developing countries. Among the institutes, the University of Sao Paulo and Harvard University have made greater efforts to investigate air pollution in developing countries. Nanjing University of Information Science& Technology had the highest frequency in a short period. Overall, this work provides a quantitative, visual, and large-scale review of the majority of publications on ‘air pollution in developing countries’ that may be important to researchers, practitioners, sponsors, and any individual/ institution concerned about air pollution.

Breathing Spaces: Modelling Exposure in Air Pollution Science

In this article, I materially situate air pollution exposure as a topic of social and political inquiry by paying attention to the increasing specificity of spaces and sites of exposure in air pollution and health research. Evidence of the unevenness of exposure and differential health effects of air pollution have led to a proliferation of studies on the risks different environments pose to bodies. There are increasingly different airs in air pollution science. In this research, bodies are often relegated to passive objects, exposed according to the environments they move between. Yet exposure implies a blurring of bodies and environments which also challenges the idea of a discrete body that is distinguishable from its material context. By studying the process of modelling indoor air pollution, I highlight how air pollution, buildings and bodies are co-implicated with one another in ways that demand new ways of materialising human exposure in science.

Model-based dense air pollution maps from sparse sensing in multi-source scenarios

A method for producing dense air pollution maps, based on any given air-pollution dispersion model, is presented. The scheme consists of two phases. At the first stage, sources' locations and emission rates, i.e., source term estimation, as a function of the model's parameter space are sought (“backward computation”). Then, the source term is used to generate the dense maps utilizing the same dispersion model (“forward computation”). The algorithm is model-invariant to the dispersion model, and thus is suitable for a wide range of applications according to the required accuracy and available resources. A simulation of an industrial area demonstrated that this method produced more accurate maps than current state-of-the-art techniques. The resulting dense air pollution map is thus a valuable tool for air pollution mitigation, regulation and research.

Science-policy interplay on air pollution governance in China

Air quality in China is a major public health, social and economic concern. Air pollution governance and research in China have been increasingly active in the past decade, especially since 2013 when strict emission controls were implemented. Such emission control policies have been informed through dialogue between scientists and policy-makers on the sources and transport of air pollution in order to identify potential control measures. However, the process of making regulatory decisions about air pollution controls at this science-policy interface in China has rarely been analysed or discussed. We outline four classical science-policy models for making regulatory decisions proposed by scholars: (i) the decisionist model – whereby policy dictates what science and regulatory decisions are required; (ii) the technocratic model – where science dictates policy directly; (iii) the inverted decisionist model (where scientists advise policy-makers on what policy is required); and (iv) the co-evolutionary model (where policy-makers and scientists jointly create regulatory decisions). Boundary-actors play a key role in this co-evolutionary model. They operate as ‘gate-keepers’ between scientists and policy-makers. Most contemporary studies of the science-policy interface argue that the co-evolutionary model best captures the reality of how science and policy interact effectively to make regulatory decisions. To assess which of these models most closely resemble decision-making at the air pollution science-policy interface, we conducted a case study on “air quality climate services” and held workshops with Chinese scientists, decision-makers and stakeholders. A typology of existing scientific approaches to explore air quality climate science is presented. The workshop results show that the current air quality climate science-policy interplay occurs most strongly in accordance with the co-evolutionary model whereby the Beijing Climate Centre and the National Environmental Monitoring Centre operate as the key boundary actors between science and policy, specifically for a seasonal air pollution haze outlook service. We illustrate that current seasonal haze outlooks carefully avoiding quantification. We then present a conceptual framework of the air pollution science-policy interface in China, which captures the main participants and the interactive flow of information between them.

Bushfire smoke: urgent need for a national health protection strategy.

This research was undertaken with support from the Australian National University College of Health and Medicine, and the assistance of resources from the Centre for Air pollution, energy and health Research (CAR). We used the CAR Data and Analysis Technology platform (https://cardat.github.io) to analyse data

Estimation of PM2.5 Emission Sources in the Tokyo Metropolitan Area by Simultaneous Measurements of Particle Elements and Oxidative Ratio in Air

Researchers across research domains have traditionally used two different methods to characterize the emission sources of pollution in the atmosphere. One of the widely used methods in the area of air pollution utilizes the ratio of elements in aerosol, namely, PM2.5. The other method used in climate-related research is the oxidative ratio (OR = −ΔO2/ΔCO2) in air. In this study, these two methods were simultaneously applied for the first time to estimate the source of PM2.5 pollution. During a week-long pollution event that occurred in the Tokyo Metropolitan area, Japan, two concentration maxima were observed in the temporal plot of PM2.5. The slope of the linear regression line for the Pb versus Ni concentration plot during the first PM2.5 concentration maximum was approximately 4 times larger than that of the second, indicating that the former was dominated by Pb-rich emission sources, that is, coal combustion. The ORs in air measured during the corresponding concentration maxima were 1.33 and 1.51, suggesting the prevailing contributions of CO2 emitted from coal and oil combustions, respectively. This suggests that the results from elemental ratio and OR analyses were consistent in identifying the emissions from these important fuel types. The results obtained in our study demonstrated that OR in the air is also applicable to estimate the emission sources of PM2.5, providing more information on the phase of the combusted materials, that is, gaseous, liquid, or solid phase. Such a study should improve the estimation of emission sources both in air pollution and climate-related research.

Combinations of Epidemiological and Experimental Studies in Air Pollution Research: A Narrative Review.

Scientific literature is evolving to include more systematic reviews that encompass epidemiological and experimental papers so that the whole picture can be examined. The aim of this narrative review is to bridge that gap by combining epidemiological and experimental studies based on the same setting: Examples of Bitterfeld, Utah Valley, Beijing Olympic Games, and Viadana. This review looks at four examples that incorporate multiple epidemiological and experimental papers about air pollution exposure and health effects. The Bitterfeld (spatial) and Utah Valley (temporal) examples showed that particle composition causes the biggest difference in lung injury. In Beijing, a temporal difference of before/after and during the Olympics showed that traffic and industry air pollution-related health effects like lung cancer and cardiovascular disease could be reduced by improvement of air quality. The Viadana example showed a spatial difference in respiratory injury caused by particle composition and interactions with genotoxicity. Combining experimental and epidemiological methods gives a more in-depth look into the whole picture of exposure and health effects. Our review exemplifies the strength of this strategy and encourages further use of it.

Application of nuclear analytical techniques to assess air quality in Indonesia

Air pollution has become a global concern because of its effects on the environment and human health. Nuclear analytical techniques (NATs) have important application in air pollution monitoring and research. NATs such as Instrumental neutron activation analysis (INAA), Particle Induced X-ray Emission (PIXE), X-ray fluoresence (XRF), and X-ray absorption near-edge structure (XANES) have been used in quantification of environmental pollutant especially airborne particulate samples (APM) collected from several cities in Indonesia. The samples were analysed for elemental concentrations by INAA at Siwabessy multipurpose reactor and Bandung TRIGA 2000 reactor in Indonesia, PIXE at Institute of Geological and Nuclear Sciences New Zealand, XRF at BATAN Bandung Indonesia, and Synchrotron facilities at Elettra Italy. The techniques provide more than 20 significant elements for identification the possible sources of atmospheric aerosol. The results demonstrated that INAA, PIXE, XRF and XANES can complement significantly the elemental characterization of APM providing the concentration of several major, minor and trace elements. These results can be used as important information on levels and sources of air pollution. It could also be used as an early warning, scientific research-based references in designing and revising various government policies and regulations related air quality standards in Indonesia.

Impact of titanium dioxide particles on adsorption properties of HZSM-5 zeolite for toluene treatment

Introduction: Today, a variety of catalysts were used for the removal of the volatile organic compound in work environments. Zeolites are frequently used as catalyst and catalyst base because of their desirable characteristics. HZSM-5 attracts the attention of air pollution researchers in recent years. The aim of this study is to investigate the adsorption properties of HZSM-5/titanium dioxide (TiO2) catalyst. Materials and Methods: A dynamic system was used for producing 42 ppm of toluene in 250C, 5% humidity, and environment pressure. For determination of adsorption capacity, 42 ppm of toluene with the flow of 0.5 L/min passed through the reactor containing 1 g of the HZSM-5/TiO2catalyst which was coated within 3%, 5%, and 8% of TiO2using impregnation method. For determination of the catalyst characteristics, different analyses of X-ray diffraction, Brunauer Emmett Teller (BET), Fourier transform infrared, and scanning electron microscope were used. Results: Adsorption capacity was 22.3, 23.81, 38.06, and 28.88 mg/g for HZSM-5, HZSM-5/Tio23%, HZSM-5/Tio25% and HZSM-5/Tio28%, respectively. The specific surface was 298.8 m2/g for HZSM-5 and 212.8, 189.3, and 185.1 m2/g for 3%, 5%, and 8% HZSM-5/TiO2catalyst, respectively. Results indicated that the breakthrough time increases by increasing in weight percent of TiO2. Adsorption isotherm was identified as type I, based on International Union of Pure and Applied Chemistry (IUPAC) classification. Conclusion: The integration of TiO2particles with HZSM-5 created a photocatalyst with desirable properties that include high adsorption capacity and long breakthrough time to maintain a high amount of toluene vapors, which lead to better removal efficiency.

Chemical Characteristics and Ozone Production in the Northern Colorado Front Range

AbstractWe use the extensive set of aircraft and ground‐based observations from the NSF/National Center for Atmospheric Research (NCAR) and State of Colorado Front Range Air Pollution and Photochemistry Éxperiment and the NASA DISCOVER‐AQ experiments in summer 2014 together with the regional chemical transport model Weather Research and Forecast Model with Chemistry (WRF‐Chem) to study the ozone production and chemical regimes in the Northern Colorado Front Range (NFR). We apply the model's Integrated Reaction Rate capability and chemical tendencies diagnostics and present results from an in‐depth analysis of the ozone formation in various NFR regions for a case study of 12 August 2014. We further apply these diagnostics along a WRF online trajectory to assess the chemical evolution of an airmass during transport. The results show efficient ozone production within the NFR driven by the availability of NOx and an abundance of highly reactive volatile organic compound and also continued ozone production during the transport into the mountains. We identify CO, formaldehyde, higher alkanes, acetaldehyde, and isoprene among the volatile organic compound species with the highest efficiency in ozone production. Formaldehyde and acetaldehyde concentrations in the NFR have a significant contribution from photochemical production, which in turn is linked back to methane oxidation and to emissions of higher alkanes, isoprene, ethane, and propane. This study provides valuable policy information into the chemical fingerprint of surface ozone in the NFR, an area that is in nonattainment of the U.S. EPA ozone health standards and demonstrates the capability of the newly added diagnostic tool in WRF‐Chem to address the drivers behind secondary production of pollutants in greater detail.

Estimating Spatio-Temporal Variations of PM2.5 Concentrations Using VIIRS-Derived AOD in the Guanzhong Basin, China

Aerosol optical depth (AOD) derived from satellite remote sensing is widely used to estimate surface PM2.5 (dry mass concentration of particles with an in situ aerodynamic diameter smaller than 2.5 µm) concentrations. In this research, a two-stage spatio-temporal statistical model for estimating daily surface PM2.5 concentrations in the Guanzhong Basin of China is proposed, using 6 km × 6 km AOD data available from the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument as the main variable and meteorological factors, land-cover, and population data as auxiliary variables. The model is validated using a cross-validation method. The linear mixed effects (LME) model used in the first stage could be improved by using a geographically weighted regression (GWR) model or the generalized additive model (GAM) in the second stage, and the predictive capability of the GWR model is better than that of GAM. The two-stage spatio-temporal statistical model of LME and GWR successfully captures the temporal and spatial variations. The coefficient of determination (R2), the bias and the root-mean-squared prediction errors (RMSEs) of the model fitting to the two-stage spatio-temporal models of LME and GWR were 0.802, −0.378 µg/m3, and 12.746 µg/m3, respectively, and the model cross-validation results were 0.703, 1.451 µg/m3, and 15.731 µg/m3, respectively. The model prediction maps show that the topography has a strong influence on the spatial distribution of the PM2.5 concentrations in the Guanzhong Basin, and PM2.5 concentrations vary with the seasons. This method can provide reliable PM2.5 predictions to reduce the bias of exposure assessment in air pollution and health research.

Coal smoke, gestational cadmium exposure, and fetal growth

BackgroundGestational cadmium exposure may impair fetal growth. Coal smoke has largely been unexplored as a source of cadmium exposure.We investigated the relationship between gestational cadmium exposure and fetal growth, and assessed coal smoke as a potential source of airborne cadmium, among non-smoking pregnant women in Ulaanbaatar, Mongolia, where coal combustion in home heating stoves is a major source of outdoor and indoor air pollution. MethodsThis observational study was nested within the Ulaanbaatar Gestation and Air Pollution Research (UGAAR) study, a randomized controlled trial of portable high efficiency particulate air (HEPA) filter air cleaner use during pregnancy, fetal growth, and early childhood development. We measured third trimester blood cadmium concentrations in 374 out of 465 participants who had a live birth. We used multiple linear and logistic regression to assess the relationships between log2-transformed maternal blood cadmium concentrations and birth weight, length, head circumference, ponderal index, low birth weight, small for gestational age, and preterm birth in crude and adjusted models. We also evaluated the relationships between log2-transformed blood cadmium concentrations and the density of coal-burning stoves within 5000 m of each participant’s apartment as a proxy of coal smoke emissions from home heating stoves. ResultsThe median (25th,75th percentile) blood cadmium concentration was 0.20 (0.15, 0.29) μg/L. A doubling of blood cadmium was associated with a 95 g (95% CI: 34, 155 g) reduction in birth weight in adjusted models. An interquartile range increase in coal stove density (from 3.4 to 4.9 gers/hectare) surrounding participants’ apartments was associated with a 12.2% (95% CI: 0.3, 25.6%) increase in blood cadmium concentrations. ConclusionsGestational cadmium exposure was associated with reduced birth weight. In settings where coal is a widely used fuel, cadmium may play a role in the putative association between air pollution and impaired fetal growth.

Monthly-Term Associations Between Air Pollutants and Respiratory Morbidity in South Brazil 2013-2016: A Multi-City, Time-Series Analysis.

Most air pollution research conducted in Brazil has focused on assessing the daily-term effects of pollutants, but little is known about the health effects of air pollutants at an intermediate time term. The objective of this study was to determine the monthly-term association between air pollution and respiratory morbidity in five cities in South Brazil. An ecological time-series study was performed using the municipality as the unit of observation in five cities in South Brazil (Gravataí, Triunfo, Esteio, Canoas, and Charqueadas) between 2013 and 2016. Data for hospital admissions was obtained from the records of the Hospital Information Service. Air pollution data, including PM10, SO2, CO, NO2, and O3 (µg/m3) were obtained from the environmental government agency in Rio Grande do Sul State. Panel multivariable Poisson regression models were adjusted for monthly counts of respiratory hospitalizations. An increase of 10 μg/m3 in the monthly average concentration of PM10 was associated with an increase of respiratory hospitalizations in all age groups, with the maximum effect on the population aged between 16 and 59 years (IRR: Incidence rate ratio 2.04 (95% CI: Confidence interval = 1.97–2.12)). For NO2 and SO2, stronger intermediate-term effects were found in children aged between 6 and 15 years, while for O3 higher effects were found in children under 1 year. This is the first multi-city study conducted in South Brazil to account for intermediate-term effects of air pollutants on respiratory health.

Impact of environmental pollution on the retrieval of AOD products from Visible Infrared Imaging Radiometer Suite (VIIRS) over wuhan

Visible Infrared Imaging Radiometer Suite (VIIRS) is a next-generation polar-orbiting operational environmental sensor, and its aerosol optical depth (AOD) data has been widely applied to ground-level PM2.5 prediction and air pollution research. However, VIIRS performance affects the accuracy of prediction. In this study, three types of VIIRS AOD products were collected from January 2014 to December 2016 to evaluate their performance under different air quality conditions. Near-surface PM2.5 concentrations were determined for the same period to categorize air quality as clean, moderate, or heavily polluted. The performance of three VIIRS AOD products was evaluated from the successful retrieval rate and AOD accuracy aspects. For clean weather days, the AODs obtained from VIIRS intermediate products (IP) had the lowest average absolute bias (0.15 ± 0.15). For the moderate and heavy pollution days, the average absolute deviations of VIIRS environmental data record (EDR) AOD (Quality Flags = 3 and >1) products were lowest at 0.14 ± 0.14 and 0.2 ± 0.1 respectively. These results suggest that the EDR AOD, Quality Flags >1 and = 3, products were more suitable for heavy and moderate air pollution, respectively. During clean weather, performance of _IP AODs was found to be best. Moreover, seasonal analysis indicated that the EDR AOD (Quality Flags = 3) products were more suitable for spring and autumn and the IP AOD for summer. However, the performance of the EDR AOD products (Quality flags > 1) were best during winter. To ensure accuracy of PM2.5 predictions over central China, researchers should carefully balance the needs for successful retrieval rate and accuracy of VIIRS AOD products.