Industrial Aerosols Research Articles

BIOLOGICAL PROPHYLAXIS IN THE SYSTEM OF THE MANAGEMENT OF OCCUPATIONAL RISK DUE TO EXPOSURE OF METAL-CONTAINING NANOPARTICLES

With taking into account the biological toxicity of metallic and metal oxide nanoparticles to be a well-established fact, the widespread use of nanotechnologies and the significant proportion of nanoscale particles in industrial aerosols released during many pyrometallurgical and electric welding processes determine the importance of searching for approaches to increase the organism’s resistance to them. Results of a number of experiments show the application of combinations of some bioactive agents composed in accordance with sound theoretical premises and used in innocuous doses to be potent of the significant attenuation of the integral and specific toxicity of metallic nanoparticles and even their genotoxicity. Further research followed by practical application of the results is a promising trend in the occupational risk management strategy.

CRITERIA FOR HYGIENIC ASSESSMENT OF AMBIENT AIR CONCENTRATIONS OF INDUSTRIAL AEROSOLS WITH A HIGH CONTENT OF AMORPHOUS SILICON DIOXIDE NANOPARTICLES

The authors consider critically some inconsistencies of applying the officially established standards for inorganic dust permissible concentrations in ambient air to amorphous silica nanoparticles-containing industrial aerosols and, relying upon their previously published experimental results, propose a feasible temporary solution to this problem for the purposes of hygienic monitoring.

Metabolic syndrome in occupational respiratory diseases

Introduction.Metabolic syndrome (MS) is currently considered as aninterdisciplinary medical problem, which is due to its wide prevalence and interrelation with the development of cardiovascular diseases and type 2 diabetes. It is of interest to study the combination of MS and respiratory diseases due to their common pathogenetic mechanisms.Objectiveis to assess an importance of studying MS in patients with occupational respiratory diseases and a possibility of using laboratory parameters as risk markers for developing occupational respiratory diseases and metabolic syndrome combination.Materials and methods.The results of examination of 257 patients with occupational bronchopulmonary pathology were analyzed. Additional tests in patients with occupational asthma (OA) included levels of serum leptin and polymorphisms of inflammatory process regulation genes (interleukins–4, 6, 10, tumor necrosis factor-α, C-reactive protein (CRP), leptin receptor).Study results and discussion.MS was detected in 58.7% of patients with occupational bronchial asthma (OA), in 44.1% of patients with occupational chronic bronchitis, in 48.6% of patients with occupational COPD, and in 38.7% of patients with pneumoconiosis. MS components appeared to be associated with respiratory function parameters. Role of Gln223Arg polymorphisms of leptin receptor gene and C3872T of CRP gene in development of leptin resistance has been confirmed. Findings are that genotype CC (C174G) of IL–6 gene gets 2.5-fold increase of MS development risk (OR=2.507, 95% CI=1.045–6.017), the presence of three or more cytokine gene polymorphisms 2.4 times increases the need to use systemic steroids to control OA (OR=2.449, 95% CI=1.127–5.324).Conclusion.Measures aimed to prevent the development of metabolic disorders in workers exposed to industrial aerosol are at the same time measures to reduce the risk of developing respiratory diseases and to prevent progression of existing diseases. Using informative laboratory markers can optimize treatment and preventive measures, taking into account the individual characteristics of the organism.

Modern approaches to prevention and treatment of dermatological diseases under influence of secondary precious metals production factors

Work conditions of main occupational groups in production of secondary precious metals, associated with exposure to multi-component industrial aerosol and heating microclimate, determine high level of relative risk of dermatologic diseases development in the workers. Etiologic share of occupational factors in formation of skin and subcutaneous tissue diseases reaches 88,8% for certain nosologies — that proves high degree of their occupational conditionality. Te authors determined length of service for risk of occupationally conditioned dermatologic diseases. Findings are that dermatologic diseases influence significantly the parameters of life quality assessed via integral dermatologic indexes. Randomized clinical study proved efficiency of emollients as addition to present treatment and prevention standards for chronic allergic dermatoses and eczema in workers engaged into secondary precious metals production.

Weekly cycle in the atmosphere aerosol variations for industrial regions

To investigate weekly cycle in aerosol parameters using recent AERONET data, we analyse the 7-days periodicity in the different regions that vary in the level of the industrial aerosol load. In the paper we are looking for the weekly cycle in atmosphere aerosol optical thickness at 440 and 870 nm (AOT440, AOT870), measured by AERONE sun-photometers in the industrial regions: Europe and North America. The possible appearance of the weekly cycle in Antarctica, where the lowest industrial aerosol load expected, was investigated as well. For each of the AERONET stations, the analysis was provided using the 8-year continuous measurement sequences data in the 2009–2016 period. Due to AERONET sun-photometers provided aerosol measurements in the daytime and cloudless conditions only, we use the weekly data overlay technique for analysis. According to this method, the initial sequence of the measurements was divided into the 7-days data segments, corresponding to a week period. The 8-year averaged values and standard deviation were calculated for an each day of week. The average Europe and North America weekend effect in the percent difference of AOT440 in the weekdays and in the weekend in the atmosphere over North America is equal 7.2%, over Europe - 4.2%. The lowest AOT values observed on Sunday and Monday the highest values are seen from Wednesday till Saturday. To reveal seasonal dependence of the weekend effect, the weekly variations of seasonally separated AOT440 and AOT870 data over Europe have been analysed. The results exhibit the maximum AOT values in working days and minimum in weekend similar to seasonally averaged results.

ALLELIC POLYMORPHISMS OF DNA REPAIR GENES AND THEIR INFLUENCE ON THE FORMATION OF RESISTANCE TO THE DEVELOPMENT OF BRONCHOPULMONARY PATHOLOGY UNDER THE ACTION OF INDUSTRIAL AEROSOLS

Introduction: The frequency of alleles and genotypes of DNA repair genes in people working due to the influence of industrial aerosols (miners and workers of asbestos-cement plants (n = 215)) was studied. The aim of the work was to identify allelic polymorphisms affecting the formation of resistance or leading to an increased risk of developing bronchopulmonary pathology. Materials and methods: In 90 patients with bronchopulmonary pathology and 125 persons working under the same conditions but without respiratory system diseases, the polymerase chain reaction in real time was determined by the polymorphisms of DNA repair genes: XPD (rs13181, rs799793), ERCC1 (rs11615), XRCC1 ( rs25487) and XRCC3 (rs861539), ATM (rs664677), XRCC7 (rs7003908) and MLH1 (rs1799977). Results: In the course of this study the alleles and genotypes contributing to resistance to the development of respiratory system pathologies were determined: XRCC1•G/A (rs25487) (OR=0.57; 95% CI: 0.32-1.02; P≤0.040; Χ²=4.14); MLH1•A (rs1799977) (OR=0.62; 95% CI: 0.40-0.96; P≤0.020; Χ²=5.06); MLH1•A/A (rs1799977) (OR=0.43; 95% CI: 0.24-0.79; P≤0.003; Χ²=8.73). Also, we established the alleles and genotypes associated with the risk of developing bronchopulmonary pathology: XPD•C/C (rs13181) (OR=2.20, 95% CI: 1.02-4.77; P≤0.020; Χ²=4.85); XRCC1•A/A (rs25487) (OR=3.37; 95 % CI: 1.22-9.63; P≤0.008; Χ²=6.94); ATM•T/T (rs664677) (OR=2.48; 95% CI: 1.16-5.31; Р≤0.010; Χ²=6.61); MLH1•G (rs1799977) (OR=1.61; 95% CI: 1.04-2.49; P≤0.020; Χ²=5.06); MLH1•A/G (rs1799977) (OR=2.32; 95% CI: 1.29-4.21; P≤0.002; Χ²=9.01). Conclusions: The results indicate the influence of allelic polymorphisms of DNA repair genes on the formation of resistance to the development of bronchopulmonary pathology under the action of industrial aerosols and open up prospects for the development of modern preventive measures.

Aerosol model evaluation using two geostationary satellites over East Asia in May 2016

This study newly applies measurements from two geostationary satellites, the Advanced Himawari Imager (AHI) onboard the geostationary satellite Himawari-8 and the Geostationary Ocean Color imager (GOCI) onboard the geostationary satellite COMS, to evaluate a unique regional aerosol-transport model coupled to a non-hydrostatic icosahedral atmospheric model (NICAM) at a high resolution without any nesting technique and boundary conditions of the aerosols. Taking advantage of the unique capability of these geostationary satellites to measure aerosols with unprecedentedly high temporal resolution, we focus on a target area (115°E-155°E, 20°N-50°N) in East Asia in May 2016, which featured the periodic transport of industrial aerosols and a very heavy aerosol plume from Siberian wildfires. The aerosol optical thickness (AOT) fields are compared among the AHI, GOCI, MODIS, AERONET and NICAM data. The results show that both AHI- and GOCI-retrieved AOTs were generally comparable to the AERONET-retrieved ones, with high correlation coefficients of approximately 0.7 in May 2016. They also show that NICAM successfully captured the detailed horizontal distribution of AOT transported from Siberia to Japan on the most polluted day (18 May 2016). The monthly statistical metrics, including correlation between the model and either AHI or GOCI, are estimated to be >0.4 in 42–49% of the target area. With the aid of sensitivity model experiments with and without Siberian wildfires, it was found that a long-range transport of aerosols from Siberian wildfires (from as far as 3000 km) to Japan influenced the monthly mean aerosol levels, accounting for 7–35% of the AOT, 26–49% of the surface PM2.5 concentrations, and 25–66% of the aerosol extinction above 3 km in height over Japan. Therefore, the air pollutants from Siberian wildfire cannot be ignored for the spring over Japan.

Establishment of a long-term lake-surface temperature dataset within the European Alps extending back to 1880

Lake surface temperature (LST) is a key characteristic of lakes, shaping the ecological properties of these inland water bodies and their environment. This study aims at establishing a long-term, high-quality, monthly LST dataset within the European Alps reaching back to 1880, which is provided to the scientific community for further research. Therefore monthly temperature records from Austrian lakes covering a period of about six decades are digitized from hydrological yearbooks. Clustering techniques (rotated empirical orthogonal functions and hierarchical cluster analysis) are used to identify groups of lakes signified by inner similarity and outer separation. These are not only used for an overall quality assessment, but also provide optimal starting conditions for the application of a homogenization procedure, warranting homogeneous LST data from 1950 onwards. LST reconstructions back to 1880 are derived from atmospheric covariates (provided by HISTALP) via sets of transfer-functions. Applied transfer-functions have passed a selection process ensuring mathematical, physical and quality requirements. They are selected from about 160 million candidates according to skill, which is determined through a comprehensive assessment based on validation experiments and several performance measures. Results show overall high skill following a seasonal cycle. From 1880 to 1950 LSTs feature generally slight increases accompanied by a succession of climate states. These are in alignment with outstanding climate periods and sustained, far-reaching repercussions triggered by significant events, which are known from historical documents. LST developments throughout the second half of the twentieth century up to date are characterized by a decline until the mid-1980s, indicating the impact of industrial aerosols. This behaviour is superseded by a steep increase, revealing the gradual unmasking of the anthropogenic greenhouse effect by the continuous reduction of aerosol loads in the atmosphere. The latter substantiates man-made climate change, whose prove is based on atmospheric variables by different data pertaining to the hydrosphere. Potential research hypotheses corresponding to various fields of science that may be investigated by using the here established LST dataset are considered. We hope that these data sets and associated findings will make a contribution to the broader research community.

DUST LUNG DISEASE FROM THE STANDPOINT OF EVIDENCE: PROFESSIONAL RISK AND MOLECULAR MARKERS

Aim - to assess the level of professional pulmonological morbidity, occupational risks and the most significant factors of the immune profile under the influence of industrial fibrogenic aerosols. Results. Mathematical modeling was carried out and a mathematical model was developed to determine the types of the disease in persons who have contact with industrial fibrogenic aerosols, and allows to correlate a new case to the group of contact (or variants of the course of dust lung diseases) or exclude the diagnosis of dust lung diseases.

Anthropogenic aerosol emissions mapping and characterization by imaging spectroscopy – application to a metallurgical industry and a petrochemical complex

ABSTRACTThis paper is focused on the retrieval of industrial aerosol optical thickness (AOT) and microphysical properties by means of airborne imaging spectroscopy. Industrial emissions generally lead to optically thin plumes requiring an adapted detection method taking into account the weak proportion of particles sought in the atmosphere. To this end, a semi-analytical model combined with the Cluster-Tuned Matched Filter (CTMF) algorithm is presented to characterize those plumes, requiring the knowledge of the soil under the plume. The model allows the direct computation of the at-sensor radiance when a plume is included in the radiative transfer. When applied to industrial aerosol classes as defined in this paper, simulated spectral radiances can be compared to ‘real’ MODTRAN (Moderate Resolution Atmospheric Transmission) radiances using the Spectral Angle Mapper (SAM). On the range from 0.4 to 0.7 µm, for three grounds (water, vegetation, and bright one), SAM scores are lower than 0.043 in the worst case (a both absorbing and scattering particle over a bright ground), and usually lower than 0.025. The darker the ground reflectance is, the more accurate the results are (typically for reflectance lower than 0.3). Concerning AOT retrieval capabilities, with a pre-calculated model for a reference optical thickness of 0.25, we are able to retrieve plume AOT at 550 nm in the range 0.0 to 0.4 with an error usually ranging between 9% and 13%. The first test case is a CASI (Compact Airborne Spectrographic Imager) image acquired over the metallurgical industry of Fos-sur-Mer (France). First results of the use of the model coupled with CTMF algorithm reveal a scattering aerosol plume with particle sizes increasing with the distance from the stack (from detection score of 54% near the stack for particles with a diameter of 0.1 µm, to 69% away from it for 1.0 µm particles). A refinement is made then to estimate more precisely aerosol plume properties, using a multimodal distribution based on the previous results. It leads to find a mixture of sulfate and brown carbon particles with a plume AOT ranging between 0.2 and 0.5. The second test case is an AHS (Airborne Hyperspectral Scanner) image acquired over the petrochemical site of Antwerp (Belgium). The first CTMF application results in detecting a brown carbon aerosol of 0.1 µm mode (detection score is 51%). Refined results show the evolution of the AOT decreasing from 0.15 to 0.05 along the plume for a mixture of brown carbon fine mode and 0.3 µm radius of sulfate aerosol.

PROFESSIONAL RISK OF THE DEVELOPMENT OF DERMATOLOGICAL DISEASES IN WORKERS OF PRODUCTION OF SECONDARY PRECIOUS METALS

Introduction. Working conditions in the metallurgical industry are characterized by the impact of unfavorable production factors on the workers of the complex. This leads to a high level of the occupational and general morbidity rate in metallurgists. The production of secondary metals is an intensively developing direction of metallurgy, which determines the urgency of studying the labor and health conditions of workers in this industry at the present stage. Material and methods. A comprehensive assessment of the working conditions of the workers of Shchelkovsky Secondary Precious Metals Plant was conducted. The occupational risk for the health of the core occupations of secondary precious metals was quantified, there were estimated the profile of occupational risk and the main unfavorable factors of the production process, making a significant contribution to the formation of dermatological morbidity of personnel. Results. Priority occupational risk factors for the formation of dermatological diseases in workers of secondary precious metals production is the impact of a multicomponent industrial aerosol and a heating microclimate. The chemical factor contributes a significant share contribution (20 - 25%) to the occupational risk profile and gives high indices of individual occupational health risks for workers in the main occupations of this production. The occupational risk of the incidence rate with a temporary disability (TD) in the enterprise as a whole is regarded as super-high. The incidence of diseases of the skin and subcutaneous tissue in workers reaches the highest level in the main production divisions and makes up in the structure of the total morbidity rate with TD of 12.3 to 14.5%. Discussion. The personal occupational risk of the secondary production of precious metals is determined by a significant proportion of employees in the core occupations with harmful working conditions on a chemical factor. The specific labor conditions of the main professional groups determine the high level of the relative risk of dermatological diseases (RR = 2.31), and the etiological share of occupational factors in their formation ranges from 56.79 to 88.84%, which proves their production conditionality.

A semi-analytical solution to Brownian coagulation of fractal aggregates valid for the entire particle size range

ABSTRACTBrownian coagulation is an important particle growth mechanism in a number of aerosol processes. Analytical solution to Brownian coagulation has been an interesting subject in aerosol population dynamics field because it can provide deep insight into the nature of the coagulation process. In the case of spherical particles, analytical solutions have been derived for all different particle size regimes. For fractal aggregates that can represent the morphology of many important industrial aerosol products and combustion soot particles, however, analytical solutions have been reported only for the free-molecule and continuum regimes. In this work, a semi-analytical solution to the Brownian coagulation of fractal aggregates valid for the entire particle size range is presented using the method of moments based on the assumption of log-normal particle size distribution. The new solution is validated by limiting-case analyses as well as by comparison with a more accurate numerical solution. The characteristics of the Brownian coagulation of fractal aggregates in the transition regime are discussed using the new solution.

CLINICAL AND FUNCTIONAL CHARACTERISTICS OF CHRONIC OBSTRUCTIVE PULMONARY DISEASE IN CONDITIONS OF EXPOSURE TO INDUSTRIAL AEROSOLS

The aim is to study the clinical and functional characteristics and indicators of blood gas composition in workers with chronic obstructive pulmonary disease (COPD) exposed to the effects of industrial aerosols (IA). Material and Methods. The study included 132 patients with a diagnosis of COPD, stage I, category C; 68 were working in conditions of exposure to IA toxico-chemical action, and 64 people had COPD (comparison group which never worked in conditions of exposure to IA). Patients in both groups were divided into 2 subgroups: subgroup 1 — the duration of exposure to IA did not exceed 10 years, 2 — more than 10 years. Spirography was carried out on the device Care Fusion UK 232 Ltd. carbon monoxide (CO) content in exhaled air was determined using gas analyzer CareFusion Smoke check. Determination of blood oxygen saturation was carried out using pulse oximetry method. The content of the partial pressure of carbon dioxide (pCO2 ) and oxygen (pO2 ) in the venous blood were studied by Astrup method. Results. Most smokers were identified in the group exposed to long-term IA. The lowest values of forced expiratory volume in one second, vital capacity and Tiffeneau index were observed among persons exposed to IA differed significantly (p<0.05) from the control group. The highest values of CO and pCO2 , and pO2 were lowest in the group of patients with COPD in the combination of IA and in smokers. Conclusion. The high frequency and long duration of smoking was found out among the workers exposed to IA. Florid violations of wheeze were detected in individuals exposed to IA. As duration of the production contact with IA increasing, more serious violations of gas exchange are formed in patients with COPD. Keywords: chronic obstructive pulmonary disease, pollutants, industrial enterprise, function of external respiration, dyspnea><0.05) from the control group. The highest values of CO and pCO2 , and pO2 were lowest in the group of patients with COPD in the combination of IA and in smokers. Conclusion. The high frequency and long duration of smoking was found out among the workers exposed to IA. Florid violations of wheeze were detected in individuals exposed to IA. As duration of the production contact with IA increasing, more serious violations of gas exchange are formed in patients with COPD.

Monitoring the industrial sources of aerosol in Cubatao, Brazil, using a scanning elastic lidar and a lidar doppler

Field campaigns with a scanning multiwavelength elastic lidar coupled with a Doppler system to monitor industrial atmospheric aerosol emissions were carried out, with the objective of monitoring aerosol emission sources and plume dispersion. Since the technique provides information on the spatial and temporal distribution of aerosol concentration, the implementation of a systematic monitoring procedure is proposed as a valuable tool in air quality monitoring applied to regions of interest.

The aerosol optical properties and PM2.5 components over the world's largest industrial zone in Tangshan, North China

To achieve an in-depth understanding of the aerosol optical properties in the highly-industrial region of Tangshan, we provided systematic aerosol optical properties analysis in this largest industrial zone for the first time. The aerosol optical datasets (2013.05–2015.04) and chemical component data of PM2.5 (2014–2015) obtained from the Tangshan site of the campaign on atmospheric aerosol research (CARE-China) network were analyzed. The results showed that the Tangshan region was seriously affected by fine-mode industrial aerosols all year, which would promote the accumulation of pollutants and influence the atmospheric circulation through changing the vertical temperature gradient. The annual average aerosol optical depth (AOD) and Ångstrӧm exponent (α) were 0.80±0.26 and 1.05±0.10, respectively. The aerosol optical properties revealed significant seasonal characteristics. The maximum seasonal average AOD (1.03±0.62) and α (1.12±0.19) accompanied the highest seasonal secondary inorganic aerosol concentrations (SIA: SO42−,NO3−,NH4+), 53.33μg/m3, occurred in summer, and this phenomenon was attributed to the photochemical reactions favored by the high temperature and humidity. During the spring, frequent dust events led to the maximum Ca2+ concentration of 6.57μg/m3 and the lowest seasonal α of 0.98±0.31. Coal was used for generating heat in winter, resulting in the highest levels of pollutant emissions (Cl−, Elemental carbon (EC) and organic carbon (OC)). The aerosol type classifications showed that the industrial aerosols were the main controls in the summer and fall, representing 56%–58% of the total aerosols. While for spring and winter, mixed aerosols represented 53%–54% of the total aerosols. Hygroscopic growth effect of aerosols existed all year, which could enhance the negative radiative forcing and eventually cool the earth-atmosphere system. The classification Wing for Tangshan data showed high AOD values (>0.70) were mainly clustered in the fine-mode growth wing and coarse-mode. Of these values, summer showed a dense AOD distribution and the highest magnitude of fine-mode AODs, with a corresponding fine particle fraction of η~90% and an Rf ~0.20μm. In addition, spring showed the most coarse-mode aerosols.

Organism's responses to a long-term inhalation of silica-containing submicron particles of an industrial aerosol

In this study we seek to understand the relation between travel information, transit use intentions and night travel. We hypothesize that transit use is related to the perceived usefulness and the ease-of-use of the system, which are related to information quality and real-time information availability. The hypothesized relations are anchored theoretically in the Technology Acceptance Model and validated empirically in two case-studies: (i) Copenhagen (Denmark), characterized by a highly integrated transit system with an advanced web-based information system; (ii) Recife and Natal (Brazil), characterized by a lower perceived level-of-service and non-integrated information sources. Data from a tailor-made survey of 1123 university students were collected. Structural equation models were employed for explaining the use of transit as a function of the observed respondent characteristics and the latent constructs. The results show that: (i) information search quality and source explain transit use; (ii) information quality underlies level-of-service and familiarity; (iii) the use of real-time information links to information quality and familiarity; (iv) general transit use and non-routine use during night and to unfamiliar places are correlated; and (v) the behavioral framework is confirmed with the two case-studies.

Aerosol manipulation through modulated multiple acoustic wavepackets with a pair of resonators

In general, the aerosols mixed in air medium can be regularly manipulated by means of the interactions between the aerosols and the acoustic field. The manipulable properties of aerosols can be engineered through geometric parameter and acoustic resonance condition of the underlying device. The aerosols manipulated by modulated multiple acoustic wavepackets (MAWP) in acoustic resonance condition is proposed and demonstrated in this paper, whose application belongs to an efficient aerosol removal technique. The experimental results indicated that the removal efficiency of aerosols was mainly influenced by the different harmonic order. The technique and process proposed in this paper was feasible for industrial application. The MAWP is modulated by means of the synthetic standing wave field at the resonant frequency 1.268kHz. The aerosol manipulation processes through MAWP consist of the aerosol shift, collision aggregation and deposition between the dot and the anti-neck of a single wavepacket. As a visual inspection confirming standing wave, the processes may also be applied in modulating the MAWP simultaneously. The manipulation efficiency can be increased due to the increase of wavepacket amount under the same operating conditions. The acoustic radiation force causes shift and accumulation of aerosol in waveguide and the secondary radiation force enhances collision aggregation and deposition thereof. The initial number concentration of particles <2.5μm (resp. larger than 2.5μm) was about 517,488 1/cf3 (resp. 51,918 1/cf3). Under the action of these forces, the aerosols in waveguide were aggregated and deposited onto the inner wall of waveguide. At the end of experiment, the final number concentration of particles <2.5μm (resp. larger than 2.5μm) is about 59,096 1/cf3 (resp. 392 1/cf3). The PM2.5 content of aerosols used in experiment is about 91%. The removal coefficients are larger than 85%. The deposition stripe distribution shows the specific pattern associated with a wavepacket. The surface of the stripe particles is covered with the uniform small hollows (~105.7–177.7nm), and plenty of nanoscale particles (~13.66–16.55nm) are grown around the surface of small hollows. It may be possible to develop a new way for large scale and batch aerosol processing to apply to the prospective emission control of industrial aerosols.

Novel Decomposition Scheme for Characterizing Urban Air Quality with MODIS

Urban air pollution is one of the most widespread global sustainability problems. Previous research has studied growth or fall of particulate matter (PM) levels using on-ground monitoring stations in urban regions. However, studying this worldwide is difficult because most cities do not have sufficient infrastructure to monitor air quality. Thus, satellite data is increasingly being employed to solve this limitation. In this paper, we use 16 years (2001–2016) of aerosol optical depth (AOD) and Angstrom exponent ( α ) datasets, retrieved from MODIS (Moderate Resolution Imaging Spectroradiometer) sensors on the National Aeronautics and Space Administration’s (NASA) Terra satellite to study air quality over 60 locations globally. We propose a novel technique, called AirRGB decomposition, to characterize urban air quality by decomposing AOD and α retrievals into ‘components’ of three distinct scenarios. In the AirRGB decomposition method, using AOD and α dataset three scenarios were investigated: ‘R’—high α and high AOD, ‘G’—high α and low AOD, and ‘B’—low α and low AOD values. These scenarios were mapped and quantified over a triangular red, green and blue color scale. This visualization easily segregates regions having a high concentration of industrial aerosol from only natural aerosols. Our analysis indicates that a sharp divide exists between North American and European cities and Asian cities in terms of baseline pollution and slopes of R and G trends. We found that while pollution in cities in China has started to decrease (e.g., since 2011 for Beijing), it continues to increase in South Asia and Southeast Asia. e.g., R offset of Beijing and New Delhi was 54.98 and 50.43 respectively but R slope was −0.04 and 0.08 respectively. High offset (≥45) and slope (≥0.025) of B for New York, Tokyo, Sydney and Sao Paolo shows that they have clean air, which is still getting better.

First results from light scattering enhancement factor over central Indian Himalayas during GVAX campaign

The present work examines the influence of relative humidity (RH), physical and optical aerosol properties on the light-scattering enhancement factor [f(RH=85%)] over central Indian Himalayas during the Ganges Valley Aerosol Experiment (GVAX). The aerosol hygroscopic properties were measured by means of DoE/ARM (US Department of Energy, Atmospheric Radiation Measurement) mobile facility focusing on periods with the regular instrumental operation (November–December 2011). The measured optical properties include aerosol light-scattering (σsp) and absorption (σap) coefficients and the intensive parameters i.e., single scattering albedo (SSA), scattering Ångström exponent (SAE), absorption Ångström exponent (AAE) and light scattering enhancement factor (f(RH)=σsp(RH, λ)/σsp(RHdry, λ)). The measurements were separated for sub-micron (<1μm, D1μm) and particles with diameter<10μm (D10μm) in order to examine the influence of particle size on f(RH) and enhancement rate (γ). The particle size affects the aerosol hygroscopicity since mean f(RH=85%) of 1.27±0.12 and 1.32±0.14 are found for D10μm and D1μm, respectively. These f(RH) values are relatively low suggesting the enhanced presence of soot and carbonaceous particles from biomass burning activities, which is verified via backward air-mass trajectories. Similarly, the light-scattering enhancement rates are ~0.20 and 0.17 for the D1μm and D10μm particles, respectively. However, a general tendency for increasing f(RH) and γ is shown for higher σsp and σap values indicating the presence of rather aged smoke plumes, coated with industrial aerosols over northern India, with mean SSA, SAE and AAE values of 0.92, 1.00 and 1.15 respectively. On the other hand, a moderate-to-small dependence of f(RH) and γ on SAE, AAE, and SSA was observed for both particle sizes. Furthermore, f(RH) exhibits an increasing tendency with the number of cloud condensation nuclei (NCCN) indicating larger particle hygroscopicity but without significant dependence on the activation ratio.

An artifact-minimizing method for total dust sampling and chemical characterization of industrial high-temperature aerosols

ABSTRACTConventional methods for total dust sampling from industrial high-temperature aerosols containing condensable species, e.g., in boilers of municipal solid waste incinerators (MSWI), are always influenced by condensation artifacts. Therefore, we extended the scope of a previously developed probe intended for size-fractionated aerosol sampling with reduced artifacts and employed it for total dust measurements. The dust is collected on quartz fiber filters, which are gravimetrically evaluated and chemically analyzed by energy dispersive X-ray spectroscopy and wet-chemical methods. First measurements in the boiler of an MSWI confirm that the probe is also suitable for artifact-minimized total dust sampling. The data are consistent with results from measurements with the size-fractionating method conducted in parallel. By combining the results of both sampling methods, we reveal the average chemical composition of the submicron particles in the aerosol, which is not accessible by one of the two methods...