Atmospheric Sulfur Dioxide Research Articles

Short-term exposure to sulfur dioxide and the occurrence of chronic obstructive pulmonary disease: An updated systematic review and meta-analysis based on risk of bias and certainty of evidence

Several studies have documented a relationship between short-term exposure to atmospheric sulfur dioxide (SO2) and chronic obstructive pulmonary disease (COPD). However, findings vary across different regions. This meta-analysis employed a random-effects model to calculate the combined risk estimate for each 10-μg/m3 increase in ambient SO2 concentration. Subgroup analysis aimed to identify sources of heterogeneity. To assess potential bias, studies were evaluated using a domain-based assessment tool developed by the World Health Organization. Sensitivity analyses, based on bias risk, explored how model assumptions influenced associations. An evidence certainty framework was used to evaluate overall evidence quality. The study protocol was registered with PROSPERO (CRD42023446823). We thoroughly reviewed 191 full-text articles, ultimately including 15 in the meta-analysis. The pooled relative risk for COPD was 1.26 (95 % CI 0.94–1.70) per 10-μg/m3 increase in ambient SO2. Eleven studies were deemed high risk due to inadequate handling of missing data. Overall evidence certainty was rated as medium. Given SO2's significant public health implications, continuous monitoring is crucial. Future research should include countries in Africa and Oceania to enhance global understanding of atmospheric SO2-related health issues.

Mysteriously rapid rise in Legionnaires' disease incidence correlates with declining atmospheric sulfur dioxide.

Legionnaires' disease (LD) is a severe form of pneumonia (∼10-25% fatality rate) caused by inhalation of aerosols containing Legionella, a pathogenic gram-negative bacteria. These bacteria can grow, spread, and aerosolize through building water systems. A recent dramatic increase in LD incidence has been observed globally, with a 9-fold increase in the United States from 2000 to 2018, and with disproportionately higher burden for socioeconomically vulnerable subgroups. Despite the focus of decades of research since the infamous 1976 outbreak, substantial knowledge gaps remain with regard to source of exposure and the reason(s) for the dramatic increase in LD incidence. Here, we rule out factors indicated in literature to contribute to its long-term increases and identify a hitherto unexplored explanatory factor. We also provide an epidemiological demonstration that the occurrence of LD is linked with exposure to cooling towers (CTs). Our results suggest that declining sulfur dioxide air pollution, which has many well-established health benefits, results in reduced acidity of aerosols emitted from CTs, which may prolong the survival duration of Legionella in contaminated CT droplets and contribute to the increase in LD incidence. Mechanistically associating decreasing aerosol acidity with this respiratory disease has implications for better understanding its transmission, predicting future risks, and informed design of preventive and interventional strategies that consider the complex impacts of continued sulfur dioxide changes.

Synthesis, characterization and application of tangerine peel-derived Fe3C/Fe-encapsulated biochar for electrochemical removal of environmental pollutant

Conforming to the principles of green chemistry and sustainable environmental progress, this work demonstrated the concept of “treating waste with waste”, i.e. treating atmospheric pollutant sulfur dioxide (SO2) with agricultural waste of tangerine peel. SO2 electro-catalytic oxidation is the key technique in this endeavor, which utilizes SO2 as reaction raw material in the anode to remove it. The anodic SO2 electro-catalytic oxidation could be coupled to the cathodic hydrogen evolution to achieve the simultaneous SO2 removal and hydrogen production. Anodic catalyst plays a vital role in this SO2 transformation. In this work, tangerine peel has been re-utilized to afford tangerine peel-derived biochar (TPB) to prepare TPB/CNT-derived Fe3C/Fe/C (N-doped) as a capable anodic catalyst to achieve this goal. With help of various characterization techniques and electrochemical testing, the optimal iron mass fraction and pyrolysis temperature were found to be 16 wt% Fe under 800 °C, with carboxylated carbon nanotube as carbon additive. Transmission electron microscopy (TEM) image showed that the as-prepared TPB/CNT-derived Fe3C/Fe/C (N-doped) featured a unique morphology to encapsulate Fe3C/Fe with a layer of protecting carbon, which should contribute to the enhanced electro-catalytic performances. A flow electrolyzer was also assembled to illustrate practical application of the anodic catalyst in the real scenario. Owing to its lower cost, the as-prepared TPB/CNT-derived Fe3C/Fe/C (N-doped) will be advantageous to replace precious metals to mediate SO2 electro-catalytic oxidation as one of promising environmental treatment techniques in the future.

Long-Term Dynamics of Atmospheric Sulfur Dioxide in Urban and Rural Regions of China: Urbanization and Policy Impacts

High levels of sulfur dioxide (SO2) due to human activities pose a serious air pollution issue in China, especially in urban agglomerations. However, limited research has investigated the impact of anthropogenic emissions on higher SO2 concentrations in urban regions compared to rural areas in China. Here, we analyzed the trends in SO2 concentrations from 1980 to 2021 in China using the Modern-Era Retrospective Analysis for Research and Applications, version 2 (MERRA-2) dataset. SO2 column concentrations from the Copernicus Atmosphere Monitoring Service (CAMS) and the Ozone Monitoring Instrument (OMI) during the years 2007–2021 were also examined for validation and comparison purposes. Eight representative areas, including four urban regions (Pearl River Delta [PRD], Beijing-Tianjin-Hebei [BTH], Yangtze River Delta [YRD], and Sichuan Basin [SCB]) and four rural regions (Northeast Region [NER], Mongolian Region [MR], West Region [WR], and Tibetan Plateau Region [TR]) were selected for the analysis. Overall, a significant but fluctuating increase in SO2 concentrations over China was observed during 1980–2021. During 1980–1997 and 2000–2010, there was an increase in SO2 concentration, while during 1997–2000 and 2010–2021, a decreasing trend was observed. The average increase in SO2 concentration was approximately 16 times higher in urban regions than in the rural background. We also found that SO2 dynamics were highly associated with expansion of urban areas, population density, and gross domestic product. Nonetheless, since 2007, SO2 concentrations have exhibited a downward trend, which is mainly attributed to the air pollution policies implemented by the Chinese government. Our findings highlight the need for further studies on the impact of SO2 on regional climate change in China.

Sulfur is in the Air: Cyanolichen Marriages and Pollution.

Cyanolichens are symbiotic organisms involving cyanobacteria and fungi (bipartite) or with the addition of an algal partner (tripartite). Cyanolichens are known for their heightened susceptibility to environmental pollution. We focus here on the impacts on cyanolichens due to rising air pollution; we are especially interested in the role of sulfur dioxide on cyanolichen biology. Cyanolichens due to air pollution including sulfur dioxide exposure, show symptomatic changes including degradation of chlorophyll, lipid membrane peroxidation, decrease in ATP production, changes in respiration rate, and alteration of endogenous auxins and ethylene production, although symptoms are known to vary with species and genotype. Sulfur dioxide has been shown to be damaging to photosynthesis but is relatively benign on nitrogen fixation which proposes as a hypothesis that the algal partner may be more in harm's way than the cyanobiont. In fact, the Nostoc cyanobiont of sulfur dioxide-susceptible Lobaria pulmonaria carries a magnified set of sulfur (alkane sulfonate) metabolism genes capable of alkane sulfonate transport and assimilation, which were only unraveled by genome sequencing, a technology unavailable in the 1950-2000 epoch, where most physiology- based studies were performed. There is worldwide a growing corpus of evidence that sulfur has an important role to play in biological symbioses including rhizobia-legumes, mycorrhizae-roots and cyanobacteria-host plants. Furthermore, the fungal and algal partners of L. pulmonaria appear not to have the sulfonate transporter genes again providing the roles of ambient-sulfur (alkanesulfonate metabolism etc.) mediated functions primarily to the cyanobacterial partner. In conclusion, we have addressed here the role of the atmospheric pollutant sulfur dioxide to tripartite cyanolichen viability and suggest that the weaker link is likely to be the photosynthetic algal (chlorophyte) partner and not the nitrogen-fixing cyanobiont.

Sea Port SO2 Atmospheric Emissions Influence on Air Quality and Exposure at Veracruz, Mexico

In this work, we identify the current atmospheric sulfur dioxide emissions of the Veracruz port, an important Mexican seaport experiencing rapid growth, and its influence on the surrounding areas. Sulfur dioxide emissions based on port activity, as well as meteorology and air quality simulations, are used to assess the impact. It was found that using marine fuel with low sulfur content reduces emissions by 88%. Atmospheric emission estimates based on the bottom-up methodology range from 3 to 7 Mg/year and can negatively impact air quality up to 3 km downwind. After evaluating different characteristics of vessels in CALPUFF, it was found that maximum sulfur dioxide concentrations ranging between 50 and 88 µg/m3 for a 24-h average occurred 500 m from the port. During 2019, five days had unsatisfactory air quality. The combination of a shallow planetary boundary layer, low wind speed, and large atmospheric emissions significantly degraded local air quality.

Modelling SO2 conversion into sulfates in the mid-troposphere with a 3D chemistry transport model: the case of Mount Etna's eruption on 12 April 2012

Abstract. Volcanic activity is an important source of atmospheric sulfur dioxide (SO2), which, after conversion into sulfuric acid, induces impacts on rain acidity, human health, meteorology and the radiative balance of the atmosphere, among others. This work focuses on the conversion of SO2 into sulfates (SO4(p)2-, S(+VI)) in the mid-tropospheric volcanic plume emitted by the explosive eruption of Mount Etna (Italy) on 12 April 2012, using the CHIMERE chemistry transport model. As the volcanic plume location and composition depend on several often poorly constrained parameters, using a chemistry transport model allows us to study the sensitivity of SO2 oxidation to multiple aspects, such as volcanic water emissions, transition metal emissions, plume diffusion and plume altitude. Our results show that two pathways contribute to sulfate production in the mid-troposphere: (1) the oxidation of SO2 by OH in the gaseous phase (70 %) and (2) aqueous oxidation by O2 catalysed by Mn2+ and Fe3+ ions (25 %). Oxidation in the aqueous phase is the faster process, but liquid water is scarce in the mid-troposphere; therefore, the relative share of gaseous oxidation can be important. After 1 d in the mid-troposphere, about 0.5 % of the volcanic SO2 was converted to sulfates via the gaseous process. Because of the nonlinear dependency of the kinetics in the aqueous phase on the amount of volcanic water emitted and on the availability of transition metals in the aqueous phase, several experiments have been designed to determine the prominence of different parameters. Our simulations show that, during the short time that liquid water remains in the plume, around 0.4 % of sulfates manage to quickly enter the liquid phase. Sensitivity tests regarding the advection scheme have shown that this scheme must be chosen wisely, as dispersion will impact both of the oxidation pathways explained above.

HEIGHT OF THE CHIMNEY FOR AN INDUSTRIAL BOILER

The quality of the surface and groundwater significantly change with the ash disposal from theflue gas stack. Atmospheric sulphur dioxide (SO2) and nitrogen dioxide (NO2) are caused for acidrain produced from fossil fuel combustion. The height of the flue gas stack is always essential tominimize the environmental impact of industrial flue gas emission. The wrong design of the fluegas stack height leads to ground-level air pollution, directly contributing to ecosystem failures andhealth impacts. The stack height depends on the sulphur content of the fuel or sulphur dioxidecontent, fuel firing rate, and the height of the tallest building within the affected area. Therefore,a new equation is developed to calculate the required minimum chimney height when sulphurcontent of the fuel and fuel consumption rate is known. Moreover, the equation is implementedto calculate the diameter of the flue gas stack. The new calculation steps are crucial for industrialapplications such as for industrial boiler to minimize air pollution.

Structure and Corrosion Resistance of Coatings Obtained by the Batch Double Hot Dip Method in Eutectoid ZnAl Bath with the Addition of Mg and Si

The article presents the results of the research determining the synergistic effect of Mg and Si additives in the ZnAl23 bath on the microstructure (SEM), growth kinetics, and corrosion resistance of coatings obtained by the batch double hot dip method. On the basis of the research on the chemical composition in micro-regions (EDS) and the research on the phase composition (XRD), the structural components of the coatings with a content of 3 and 6 wt.% Mg and 0.2–0.4 wt.% Si were identified. The corrosion resistance of the coatings was compared with that of the reference coating obtained in the ZnAl23Si0.4 bath in the neutral salt spray test (EN ISO 9227), and the test with sulfur dioxide in a humid atmosphere (EN ISO 6988). The parameters of electrochemical corrosion of the coatings were determined. This allowed for the conclusion that the addition of Mg and Si to the ZnAl23 bath improved the microstructural uniformity of the coating. In the area of the diffusion layer, the presence of the FeAl3 intermetallic phase was found, while in the outer layer the dendrite of the Al-rich solution with interdendritic spaces, where it locates areas of Zn-rich solution, eutectic Zn/MgZn2 or phase separation MgZn2 and Mg2Si are located. Additions of Mg and Si stabilize the kinetics of the coating’s growth, and its course is parabolic. The conducted corrosion tests showed better corrosion resistance of the coatings obtained in the bath with Mg addition compared to the reference coating obtained in the ZnAl23Si bath. The increase in corrosion resistance results from the presence of a more anodic MgZn2 phase, which, however, may be weakened by the presence of Mg2Si phase precipitates.

Prediction of atmospheric corrosion from meteorological parameters: Case of the atmospheric basin of the Costa Rican Western Central Valley

The assessment of atmospheric corrosion is currently based on the study of atmospheric basins (AB). Modeling atmospheric corrosion in many cases involves the measurement of several meteorological and atmospheric pollution parameters, specifically temperature, relative humidity, chloride, and sulfur dioxide, making the estimation process more complex. However, for the Western Central Valley (WCV) in Costa Rica, a low-pollution AB, it is possible to develop simplified atmospheric corrosion models based on a small number of atmospheric parameters. In this paper, the meteorological variables of the study region were analyzed in terms of their dependency on altitude and their applicability in the development of a simplified model to predict the corrosion rate (Vcorr). The output of the predictive model was compared with the standard model of ISO 9223:2012, showing a higher skill and giving reliable results for a wide interval of altitudes.

Discussion on Quality Control in Sampling and Analysis of Atmospheric Sulfur Dioxide

Discussion on Quality Control in Sampling and Analysis of Atmospheric Sulfur Dioxide

Stalled high-pressure weather systems

Stalled High Pressure Weather Systems (SHPWS) are associated with abnormally high temperatures, low wind velocities (except at their peripheries, where they can be quite high), cloudless skies, and a consequent lack of precipitation. Analysis shows that the high temperatures and clear skies associated with their formation are caused by the settling out of reflective (dimming) atmospheric Sulfur Dioxide (SO2) aerosols within the area of a “High”. This cleansing of the atmosphere allows sunshine to strike the Earth’s surface with greater intensity, resulting in substantially increased warming.

Evaluation of the effect of Global Sulfur Cap 2020 on a Japanese inland sea area

The Global Sulfur Cap 2020 regulation requires a decrease in the sulfur content in the fuel oil used on ships from 3.5% to 0.5%. In this study, atmospheric sulfur dioxide (SO2), nitrogen oxide (NOx), and fine particulate matter concentrations were measured in the Seto Inland Sea, a congested sea area in Japan. A rapid decrease was observed in ship emission indices, such as SO2, vanadium (V), nickel (Ni), and the V/Ni ratio, at coastal monitoring stations, providing evidence of the implementation of this regulation. Onboard observations clearly revealed a decrease in maritime gaseous SO2 immediately after the regulation came into effect; similar changes were observed in the coastal areas from January to June in 2019–2020. Although continuous studies will be needed to distinguish the benefits of the regulation from those of other factors, these findings will be useful for policymakers when addressing atmospheric pollution issues in congested sea areas.

Analysis of atmospheric SO2 in Sichuan-Chongqing region based on OMI data.

The Sichuan-Chongqing region is the leader and growth pole of economic development in western China. With the rapid development of economy and unique geographical environment, high concentration of sulfur dioxide air pollution has existed for a long time in Sichuan-Chongqing area. Based on 10years of remote sensing data, this paper studies the temporal and spatial distribution characteristics, stability, and influencing factors of sulfur dioxide in this area. Based on potential sources, the impact of surrounding areas on sulfur dioxide in Sichuan and Chongqing is analyzed. The results shows that the spatial distribution of sulfur dioxide in the Sichuan-Chongqing region is higher in the southeast and lower in the west. The Midwest region has low fluctuation and good stability. The time distribution shows obvious seasonal regularity. The concentration of sulfur dioxide is affected by socio-economic factors and natural factors. In this study, it is found that the distribution of sulfur dioxide is closely related to PM2.5, which provides an important reference for the comprehensive management of air pollution. The OMI data effectively reflects the distribution and change of atmospheric sulfur dioxide in the Sichuan-Chongqing region, and provides certain ideas for air pollution control in the Sichuan-Chongqing region and other regions in China.

The influence of light and relative humidity on the formation of epsomite in cadmium yellow and French ultramarine modern oil paints

The effect of relative humidity (RH) and light on the development of epsomite (MgSO4·7H2O) in Winsor & Newton cadmium yellow (CY) and French ultramarine (FU) artists’ oil colour paints was investigated. Tube paint samples were aged for 12 weeks at either 50% or 75% RH, under ambient light (200 ± 1 lx), elevated light (11,807 ± 328 lx), and near-dark conditions. Aged paint samples were characterised using light microscopy (LM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). Results indicated that ageing at 75% RH in elevated light conditions, promoted the formation of hydrated magnesium sulphate (MgSO4·6–7H2O) crystals on the surface of both paints. The formation of sodium sulphate (Na2SO4) as a degradation product of French ultramarine oil paints after ageing at 75% RH in elevated light conditions is described. The formation of magnesium sulphate crystals in the absence of elevated SO2 is a new finding. For both cadmium yellow and French ultramarine oil paints, the pigments present are a likely source of sulphur, enabling the formation of sulphate salts, i.e., cadmium sulphide (CdS) yellow, and the sulphur radical anions (S3−) present in ultramarine pigment. Sulphur-containing impurities arising from pigment manufacture are an additional possibility. It was previously theorised that epsomite formation in water-sensitive twentieth century oil paintings resulted from exposure to the elevated atmospheric sulphur dioxide (SO2) levels of the 1950s–1970s. This study demonstrates that hydromagnesite-containing cadmium yellow and French ultramarine oil paints of any period may be vulnerable to water-soluble sulphate salts formation and that this process is promoted by exposure to light and high (75%) RH environments. The formation of sulphate salts as a degradation product is known to contribute toward the development of water sensitivity of modern oil paintings which can pose significant challenges to conservation. Therefore this study highlights the importance of minimising exposure to light and raised relative humidity for paintings containing such CY and FU oil paint passages, to help slow down these types of degradation phenomena which have implications for preservation.

The response of streams in the Adirondack region of New York to projected changes in sulfur and nitrogen deposition under changing climate

Modeling studies project that in the future surface waters in the northeast US will continue to recover from acidification over decades following reductions in atmospheric sulfur dioxide and nitrogen oxides emissions. However, these studies generally assume stationary climatic conditions over the simulation period and ignore the linkages between soil and surface water recovery from acid deposition and changing climate, despite fundamental impacts to watershed processes and comparable time scales for both phenomena. In this study, the integrated biogeochemical model PnET-BGC was applied to two montane forest watersheds in the Adirondack region of New York, USA to evaluate the recovery of surface waters from historical acidification in response to possible future changes in climate and atmospheric sulfur and nitrogen deposition. Statistically downscaled climate scenarios on average project warmer temperatures and greater precipitation for the Adirondack by the end of the century. Model simulations suggest under constant climate, acid-sensitive Buck Creek would gain 12.8 μeq L−1 of acid neutralizing capacity (ANC) by 2100 from large reductions in deposition, whereas acid insensitive Archer Creek is projected to gain 7.9 μeq L−1 of ANC. However, climate change could limit those improvements in acid-base status. Under climate change, a negative offset relative to the ANC increases with no climate change are projected for both streams by 2100. In acid-insensitive Archer Creek the negative offset (−8.5 μeq L−1) was large enough that ANC is projected to decrease by −0.6 μeq L−1, whereas in acid-sensitive Buck Creek, the negative offset (−0.4 μeq L−1) resulted in a slight decline of the projected future ANC increase to 12.4 μeq L−1. Calculated target loads for 2150 for both sites decreased when future climate change was considered in model simulations, which suggests further reductions in acid deposition may be necessary to restore ecosystem structure and function under a changing climate.

The development of a genetic method to optimize the flue gas desulfurization process

Sulfur dioxide is one of the most commonly found gases, which contaminates the air, damages human health and the environment. To decrease the damage, it is important to control the emissions on power stations, as the major part of sulfur dioxide in atmosphere is produced during electric energy generation on power plants. The present work describes flue gas desulfurization process optimizing strategy using data mining. The optimisation modified genetic method of flue gas desulfurization process based on artificial neural network was developed. It affords to represent the time series characteristics and factual efficiency influence on desulfurization and increase its precision of prediction. The vital difference between this developed genetic method and other similar methods is in using adaptive mutation, that uses the level of population development in working process. It means that less important genes will mutate in chromosome more probable than high suitability genes. It increases accuracy and their role in searching. The comparison exercise of developed method and other methods was done with the result that new method gives the smallest predictive error (in the amount of released SO2) and helps to decrease the time in prediction of efficiency of flue gas desulfurization. The results afford to use this method to increase efficiency in flue gas desulfurization process and to decrease SO2 emissions into the atmosphere

One Step Ahead Prediction of Ozone Concentration for Determination of Outdoor Air Quality Level

With the rapid spread of urbanization, competent authorities become increasingly anxious from air pollution risks and effect on citizens especially those with respiratory diseases. In this work, performances of six machine learning methods were analyzed for prediction of maximum ozone (O_3) concentration for the next-day. The models make the prediction using concentrations of six atmospheric components (PM2.5, PM10, Ozone (O3), Sulfur Dioxide (SO2), Nitrogen Dioxide (NO2), and Carbon Monoxide (CO)). The utilized machine learning methods are multilayer perception (MLP), Support Vector Regression (SVM), k-Nearest Neighbor (K-NN), Random Forests (RF), Gradient Boosting (GB), and Elastic Net (EN). After the predictions made by these models, the predicted values were further processed to be classified into one of the six air quality levels defined by United States Environmental Protection Agency. The prediction performances of the models as well as their corresponding classification results were analyzed. It was shown that MLP model gives the lowest RMSE of 2246 for prediction step while SVR achieved the highest accuracy score of 0.790.

Chemical Characteristics of Cloud Water and Sulfate Production Under Excess Hydrogen Peroxide in a High Mountainous Region of Central Japan

Over the last two decades, atmospheric sulfur dioxide (SO2) concentrations have decreased in air-polluted regions. However, this decrease was accompanied by a rise in cloud water acidity (pH), which remains below 5. With this change, gas-phase hydrogen peroxide (H2O2) exceeded SO2 in most of these regions. These conditions where SO2 10) in our observation site, which was due to power plant restrictions in Japan since the 1970s. The ion species concentrations in cloud water indicated that cloud acidification resulted from dissolution of gaseous HNO3 and SO2, whereas gaseous hydrochloric acid and organic acid had a minor contribution to the acidification. Significant losses of Cl− and Mg2+ were observed in some of the cloud water. The excess value of non-sea-salt sulfate (nss-SO42−) over NH4+ in cloud water implies the in-cloud oxidation of gaseous SO2 to aqueous SO42−. A Se tracer technique was used to conduct in-situ measurements of in-cloud SO42− production. The results showed that the in-cloud production varied in a range between 7 ± 2 and 41 ± 14%. This temporal variation might be due to ambient SO2 concentrations based on Henry’s law.

Catalytic oxidation of CO on noble metal-based catalysts.

Carbon monoxide (CO) catalytic oxidation has gained increasing interest in recent years due to its application prospects. The noble metal catalysts commonly exhibit outstanding CO catalytic oxidation activity. Therefore, this article reviewed the recent research on the application of noble metal catalysts in the catalytic oxidation of CO. The effects of catalyst support, dopant, and physicochemical properties on the catalytic activity for CO oxidation are summarized. The influence of the presence of water vapor and sulfur dioxide in the reaction atmosphere on the catalytic activity in CO oxidation is emphatically discussed. Moreover, this paper discussed several reaction mechanisms of CO catalytic oxidation on noble metal catalysts. Finally, the challenges of removing CO by catalytic oxidation in practical industrial flue gas are proposed.