High SO2 Levels Research Articles

Does ambient air pollutants increase the risk of fetal loss? A case–control study

To examine the associations between the ambient air pollution and early fetal loss. A retrospective case-control study was conducted. 959 fetal losses and 959 normal intrauterine pregnancies within 14 weeks of pregnancy in 15 general or obstetrics and gynecology hospitals were selected into case and control groups, respectively. Data based on hospital records and national pollution monitor station records were collected. Logistic regression model was conducted to examine the associations between 4 ambient air pollutants (SO2, PM10, NO2 and TSP) exposures and fetal loss. The ratio of fetal loss to termination of pregnancy for heating months (2.28 %) was significantly (P < 0.001) higher than that for the non-heating months (1.77 %). Logistic regression suggested that fetal loss within 14 weeks was associated with higher exposure to SO2 (OR = 19.76, 95 % CI 2.34-166.71) and TSP (OR = 2.04, 95 % CI 1.01-4.13) in the first month of pregnancy. Exposure to high levels of SO2 and TSP during the first month of pregnancy was associated with an increased risk of fetal loss in early pregnancy.

Survival of the scorpion &lt;i&gt;Opistophthalmus pugnax&lt;/i&gt; (Scorpionidae) after exposure to a lethal dosage SO&lt;sub&gt;2&lt;/sub&gt; gas.

Scorpions are well known for their ability to adapt to dry habitats, scarcity of food and radioactive radiation. Nothing is known about their response to toxic gases. Results from this experiment showed that a high dose of 1000 parts per million SO2 was not lethal for Opistophthalmus pugnax; compare this to humans who cannot tolerate and survive high SO2 levels. In fact, the oxygen production rate increased from 4.16 µmol/g-1hour-1 to 7.69 µmol/g-1hour-1 after exposure of one hour to SO2. Forty minutes after exposure, ṀO2 was still nearly twice as high compared with the ṀO2 value at the beginning. Further experiments are suggested to solve the problem of possible spiracle occlusion caused by SO2.

Effect of SO2 on CO2 Capture Using Liquid-like Nanoparticle Organic Hybrid Materials

Liquid-like nanoparticle organic hybrid materials (NOHMs), consisting of silica nanoparticles with a grafted polymeric canopy, were synthesized. Previous work on NOHMs has revealed that CO2 capture behaviors in these hybrid materials can be tuned by modifying the structure of the polymeric canopy. Because SO2, which is another acidic gas found in flue gas, would also interact with NOHMs, this study was designed to investigate its effect on CO2 capture in NOHMs. In particular, CO2 capture capacities as well as swelling and CO2 packing behaviors of NOHMs were analyzed using thermogravimetric analyses and Raman and attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopies before and after exposure of NOHMs to SO2. It was found that the SO2 absorption in NOHMs was only prominent at high SO2 levels (i.e., 3010 ppm; Ptot = 0.4 MPa) far exceeding the typical SO2 concentration in flue gas. As expected, the competitive absorption between SO2 and CO2 for the same absorption sites (i.e., ether and amine groups) resulted in a decreased CO2 capture capacity of NOHMs. The swelling of NOHMs was not notably affected by the presence of SO2 within the given concentration range (Ptot = 0–0.68 MPa). On the other hand, SO2, owing to its Lewis acidic nature, interacted with the ether groups of the polymeric canopy and, thus, changed the CO2 packing behaviors in NOHMs.

Ecological Study on Hospitalizations for Cancer, Cardiovascular, and Respiratory Diseases in the Industrial Area of Etang-de-Berre in the South of France

The Etang-de-Berre area is a large industrialized area in the South of France, exposing 300,000 inhabitants to the plumes of its industries. The possible associated health risks are of the highest concern to the population, who asked for studies investigating their health status. A geographical ecological study based on standardized hospitalizations ratios for cancer, cardiovascular, and respiratory diseases was carried out over the 2004–2007 period. Exposure to air pollution was assessed using dispersion models coupled with a geographic information system to estimate an annual mean concentration of sulfur dioxide (SO2) for each district. Results showed an excess risk of hospitalization for myocardial infarction in women living in districts with medium or high SO2 exposure, respectively, 38% [CI 95% 4 : 83] and 54% [14 : 110] greater than women living in districts at the reference level exposure. A 26% [2 : 57] excess risk of hospitalization for myocardial infarction was also observed in men living in districts with high SO2 levels. No excess risk of hospitalization for respiratory diseases or for cancer was observed, except for acute leukemia in men only. Results illustrate the impact of industrial air pollution on the cardiovascular system and call for an improvement of the air quality in the area.

Bisulfate Dehydration at Air/Solution Interfaces Probed by Vibrational Sum Frequency Generation Spectroscopy

The structure and organization of ions at vapor/solution interfaces have great implications for the reactivity and growth of atmospheric aerosols. Considering the ionic components of aqueous aerosols, sulfate species are one of the most prevalent due to high levels of SO2(g) emission to the atmosphere from biofuel burning and volcanic eruptions. Atmospheric SO2(g) can undergo direct gas phase oxidation or experience dissolution and subsequent oxidation to sulfate species within aqueous aerosols, where, depending on the pH level, sulfate may exist as SO42–, HSO4–, or H2SO4. Here we probe the molecular environment experienced by the bisulfate anion (HSO4–) at vapor/solution interfaces for H2SO4, Na2SO4, and MgSO4 solutions via vibrational sum frequency generation (VSFG) spectroscopy. VSFG is an inherently interface specific nonlinear optical spectroscopy and is a powerful tool for the study of interfacial structure and organization. Our VSFG results are compared to bisulfate behavior in bulk aqueous solutio...

Study of a high SO2 event observed over an urban site in western India

Continuous measurements of SO2, NOx and O3 along with sampling based measurements of CO, CH4, NMHCs and CO2 were carried out during May, 2010 at Ahmedabad. The diurnal variations of SO2 in ambient air exhibited elevated values during the night and lower levels during the sunlit hours. The mean concentration of SO2 during the study period was 0.95 ± 0.88 ppbv. However, the ambient SO2 exceeded 17 ppbv in the night of 20 May, 2010. On the same day, tropospheric columnar SO2 from OMI showed almost 350% increase corroborating the surface observations over an extended height regime. This was also the highest columnar value of SO2 during the summer of 2010. Columnar loadings were also found to be high for formaldehyde, precipitable water vapor and aerosol optical depth on 20 May. Elevated concentrations were also recorded for other trace gases like NO2 and O3. Analysis of related data of trace gases indicated characteristics of fresh emissions with dominant contributions from mobile sources during the study period. However, SO2/NO2 ratio of 0.36 during the event period on 20th May connotes non-local influences. Analyses of meteorological parameters suggest combined impacts of transport and inversion causing higher levels of SO2 and other pollutants during 20–21 May. Episodes of such enhancements may perturb chemical and radiative balance of the atmosphere.

Lichens as biomonitors of sulphur dioxide and nitrogen dioxide pollution in Colombo and suburbs

Biological monitoring is an efficient and inexpensive method for monitoring air quality. Studies have confirmed that lichens are among the most reliable accumulators of airborne inorganic contaminants. As limited research has been done in tropics with regard to biological monitoring, a study was carried out to monitor lichen diversity and distribution in selected locations in Colombo and its suburbs.Thirty one sites located on six radial transects diverging from Colombo Fort were selected for this study. Eight trees from three trees species, (Cocos nucifera, Mangifera indica, and Artocarpus heterophyllus) within each site (1km2) were chosen for the study. Coverage and frequency of corticolous all lichens found on selected trees were recorded by using 250 cm2 grids. After studying their morphology, anatomy, reproductive structures and chemistry, lichens collected were identified using keys. In addition, land use pattern, traffic density, pH of substrates, exposure levels of these sites to light were also recorded. Ambient SO2 and NO2 levels at each site were determined using passive samplers having filter pads coated with the absorbing reagents, ethylene glycol and acetone, for SO2 and NaI, NaOH and Ethylene glycol for NO2. Data were statistically analyzed by using the mean comparison, correlation and by principal component analysis to investigate relationship between diversity of lichens and environmental parameters.Forty seven genera of lichens were identified, out of them ten genera are sensitive to air pollutants. The highest atmospheric SO2 and NO2 levels (48.35µg/m3 and 42.825µg/m3) as well as the lowest lichen diversity (0.8374) were recorded from the site located in Colombo Fort. When land use pattern changed from village to urban and with increase of traffic density of sites, diversity of lichens reduced significantly. The relationship between diversity of lichens and levels of SO2 and NO2 was negatively correlated but significant only with levels of NO2. Further, a significant negative correlation was found between the pH of substrates and levels of SO2 and NO2. Principal component analysis revealed that principal component 1(PC1), PC2 and PC3 explain 38%, 20% and 15% of the total variation in the data set respectively. Biplot developed by PC1 vs PC2 revealed that low lichen diversity class is clearly separated from other classes due to increased concentrations of SO2, NO2, land use pattern and the traffic density, all of which are included in PC1. Bark pH values of Cocos nucifera and Artocarpus heterophyllus that are represented by PC2 also had contributed to above grouping. Index of atmospheric purity (IAP) values increased along all transect with gradual decrease of SO2 and NO2 levels when moving away from the city.Absence of several pollutant sensitive tropical lichens and decrease of lichen diversity in sites with high levels of SO2 and NO2, indicate that tropical lichens have the potential to be used as indicators in air pollution monitoring work.

Rapid recovery of stem increment in Norway spruce at reduced SO2 levels in the Harz Mountains, Germany

Tree-ring width of Picea abies was studied along an altitudinal gradient in the Harz Mountains, Germany, in an area heavily affected by SO2-related forest decline in the second half of the 20th century. Spruce trees of exposed high-elevation forests had earlier been shown to have reduced radial growth at high atmospheric SO2 levels. After the recent reduction of the SO2 load due to clean air acts, we tested the hypothesis that stem growth recovered rapidly from the SO2 impact. Our results from two formerly damaged high-elevation spruce stands support this hypothesis suggesting that the former SO2-related spruce decline was primarily due to foliar damage and not to soil acidification, as the deacidification of the (still acidic) soil would cause a slow growth response. Increasing temperatures and deposited N accumulated in the topsoil are likely additional growth-promoting factors of spruce at high elevations after the shortfall of SO2 pollution.

The prevalence and incidence of sick building syndrome in Chinese pupils in relation to the school environment: a two-year follow-up study

There are few incidence studies on sick building syndrome (SBS). We studied two-year change of SBS in Chinese pupils in relation to parental asthma/allergy (heredity), own atopy, classroom temperature, relative humidity (RH), absolute humidity (AH), crowdedness, CO₂, NO₂, and SO₂. A total of 1993 participated at baseline, and 1143 stayed in the same classrooms after two years. The prevalence of mucosal and general symptoms was 33% and 28% at baseline and increased during follow-up (P < 0.001). Twenty-seven percent reported at least one symptom improved when away from school. Heredity and own atopy were predictors of SBS at baseline and incidence of SBS. At baseline, SO₂ was associated with general symptoms (OR=1.10 per 100 μg/m³), mucosal symptoms (OR=1.12 per 100 μg/m³), and skin symptoms (OR=1.16 per 100 μg/m³). NO₂ was associated with mucosal symptoms (OR=1.13 per 10 μg/m³), and symptoms improved when away from school (OR=1.13 per 10 μg/m³). Temperature, RH, AH, and CO₂ were negatively associated with prevalence of SBS. Incidence or remission of SBS was not related to any exposure, except a negative association between SO₂ and new skin symptoms. In conclusion, heredity and atopy are related to incidence and prevalence of SBS, but the role of the measured exposures for SBS is more unclear. We found high levels of CO₂ indicating inadequate ventilation and high levels of SO₂ and NO₂, both indoors and outdoors. All schools had natural ventilation, only. Relying on window opening as a tool for ventilation in China is difficult because increased ventilation will decrease the level of CO₂ but increase the level of NO₂ and SO₂ indoors. Prevalence studies of sick building syndrome (SBS) might not be conclusive for causal relationships, and more longitudinal studies on SBS are needed both in China and other parts of the world. The concept of mechanical ventilation and air filtration should be introduced in the schools, and when planning new schools, locations close to heavily trafficked roads should be avoided.

Analysis of black carbon, particulate matter, and gaseous pollutants in an industrial area in Korea

Abstract Continuous mass concentrations of black carbon (BC), particulate matter (PM10 and PM2.5), CO, NO2, SO2, benzene, toluene, and xylene were measured in an industrial area in Incheon City, Korea. Principal component analysis (PCA) results revealed that PC1 had high contributions from PM10, PM2.5, CO, and benzene (31.225%), and was strongly associated with vehicular emissions and industrial sources, the major contributors to air pollution in Incheon. PC2 was heavily enriched with NO2 and BC (24.555%), and was attributed to emissions from vehicles such as buses, vans, taxis, cars, motorcycles, and trucks. PC3 was highly enriched with toluene and xylene (20.884%), and thus represented solvent usage. PC4 was enriched with SO2 (12.884%), which could be attributed to the high S content in diesel fuel used in trucks, which may contribute to the high ambient levels of SO2 in the city. Cluster analysis (CA) revealed four subgroups: Cluster 1 (SO2), Cluster 2 (toluene and xylene), Cluster 3 (NO2 and BC), and Cluster 4 (PM10, PM2.5, CO, and benzene), which agree with the PCA results. This study showed that benzene had a higher correlation with PM2.5, PM10, and CO than toluene and xylene, providing insights into source contributions that, together with a source-species atmospheric dispersion model, can be used to devise new control strategies for industrial urban areas. Our results suggest that appropriate vehicle emission management coupled with industrial air pollution control should be applied to fine particulate (PM2.5) and gaseous pollutants including benzene, toluene, ethylbenzene, and xylenes in the study area.

Agricultural Fire Impacts on the Air Quality of Shanghai during Summer Harvesttime

ABSTRACTAgricultural fire is an important source of atmospheric carbonaceous aerosols. To better understand biomass burning emission originating from fire over Asian agriculture areas and its transport into the downwind atmosphere, aerosols and major trace gases were measured continuously from 22 May to 30 June at Shanghai during the summer harvesttime of 2009. Water-soluble K material contained in aerosols showed a clear day-to-day pattern with an average of 1.25 ± 1.48 µg/m3. K ion loading and ratio of K ion to PM10 drastically increased during ‘K event’ days, accompanying with high PM10, SO2, and NO2 levels. MODIS remote sensing fire map revealed about 80% agricultural fires occurred in the agriculture areas of Anhui, Jiangsu, Shandong and Henan provinces. Four potential source areas of agricultural fires, identified as Shanghai, Zhejiang, Jiangsu and Anhui provinces, had significant contributions to worsen the air quality of Shanghai during the harvest season.

Global warming and alternative causes of decline in arctic‐alpine and boreal‐montane lichens in North‐Western Central Europe

AbstractLichens are thought to be sensitive indicators of global warming, as the spread of several thermophilous epiphytes in north‐western Central Europe has been attributed to late 20th century warming. In the present paper, the potential contribution of late 20th century warming to the decline of arctic‐alpine and boreal‐montane lichen species is analyzed. Relevant ecological groups of lichens include terricolous heathland species, saxicolous species of exposed rock outcrops and boulder fields as well as epiphytes of mountain forests. These three groups of lichens experienced significant declines before the onset of late 20th century warming in the 1970s. These declines can be attributed to the abandonment of traditional land use systems in the case of the heathland lichens, increased recreational use of the exposed summits usually inhabited by cold‐tolerant saxicolous lichens, and to high atmospheric SO2 levels in the mid‐20th century, but are probably not directly connected to global warming.

Tula industrial complex (Mexico) emissions of SO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; and NO&amp;lt;sub&amp;gt;2&amp;lt;/sub&amp;gt; during the MCMA 2006 field campaign using a mobile mini-DOAS system

Abstract. The Mexico City Metropolitan Area (MCMA) has presented severe pollution problems for many years. There are several point and mobile emission sources inside and outside the MCMA which are known to affect air quality in the area. In particular, speculation has risen as to whether the Tula industrial complex, located 60 km northwest of the MCMA has any influence on high SO2 levels occurring on the northern part of the city, in the winter season mainly. As part of the MILAGRO Field Campaign, from 24 March to 17 April 2006, the differential vertical columns of sulfur dioxide (SO2) and nitrogen dioxide (NO2) were measured during plume transects in the neighborhood of the Tula industrial complex using mobile mini-DOAS instruments. Vertical profiles of wind speed and direction obtained from pilot balloons and radiosondes were used to calculate SO2 and NO2 emissions. According to our measurements, calculated average emissions of SO2 and NO2 during the field campaign were 384±103 and 24±7 tons day−1, respectively. The standard deviation of these estimations is due to actual variations in the observed emissions from the refinery and power plant, as well as to the uncertainty in the wind fields at the exact time of the measurements. Reported values in recent inventories were found to be in good agreement with calculated emissions during the field campaign. Our measurements were also found to be in good agreement with simulated plumes.

Tail-Gas Cleanup by Simultaneous SO2and H2S Removal

Tail-gas streams from refinery processes such as Claus units often contain and emit SO2 and H2S at levels exceeding permissible emission limits, which are currently set at 10 ppm H2S and 250 ppm SO2 (U.S.). Gas compositions vary widely depending on the application, with some containing high levels of SO2, H2S, and moisture. This publication describes the simultaneous removal of these sulfur-containing contaminants utilizing a regenerable catalytic sorbent. A simplified process with the potential to reduce a four-stage process to a two-stage process is presented. The new process would compete with currently established technologies such as amine scrubbers or Cansolv units (property of Cansolv Technologies Inc., Montreal, Quebec, Canada H2M 2N9).

Sintering and Reactivity of CaCO3-Based Sorbents for In Situ CO2 Capture in Fluidized Beds under Realistic Calcination Conditions

Sintering during calcination/carbonation may introduce substantial economic penalties for a CO2 looping cycle using limestone/dolomite-derived sorbents. Here, cyclic carbonation and calcination reactions were investigated for CO2 capture under fluidized bed combustion FBC conditions. The cyclic carbonation characteristics of CaCO3-derived sorbents were compared at various calcination temperatures 700-925°C and different gas stream compositions: pure N2 and a realistic calciner environment where high concentrations of CO280-90% and the presence of SO2 are expected. The conditions during carbonation employed here were 700°C and 15% CO2 in N2 and 0.18% or 0.50% SO2 in selected tests, i.e., typically expected for a carbonator. Up to 20 calcination/carbonation cycles were conducted using a thermogravimetric analyzer TGA apparatus. Three Canadian limestones were tested: Kelly Rock, Havelock, and Cadomin, using a prescreened particle size range of 400-650 m. In addition, calcined Kelly Rock and Cadomin samples were hydrated by steam and examined. Sorbent reactivity was reduced whenever SO2 was introduced to either the calcining or carbonation streams. The multicyclic capture capacity of CaO for CO2 was substantially reduced at high concentrations of CO2 during the sorbent regeneration process and carbonation conversion of the Kelly Rock sample obtained after 20 cycles was only 10.5%. Hydrated sorbents performed better for CO2 capture, but also showed significant deterioration following calcination in high CO2 gas streams. This indicates that high CO2 and SO2 levels in the gas stream lead to lower CaO conversion because of enhanced sintering and irreversible formation of CaSO4. Such effects can be reduced by separating sulfation and carbonation and by introducing steam to avoid extremely high CO2 atmospheres, albeit at a higher cost and/or increased engineering complexity.

Influência do aquecimento sobre diferentes métodos de titulação de SO&lt;sub&gt;2&lt;/sub&gt; residual em camarões &lt;em&gt;Litopenaeus vannamei&lt;/em&gt; (Boone, 1931)

Sodium metabisulfite is the most applied preservative in shrimp culture, with its use supported by current legislation; however, its residue, sulfur dioxide (SO2), in high concentrations can provoke adverse health reactions. This study evaluated the influence of heating under different methods of residual SO2) titration in em>Litopenaeus vannamei. Shrimps were treated with nine concentrations of sodium metabisulfite and evaluated by different methods of SO2) titration. The adapted Adolfo Lutz titration method presented the highest sensitivity for the detection of SO2). The method of iodometric titration with heating made possible the detention of higher levels of SO2), when compared to the same method without heating. The heating influenced negatively on the reactive ribbon method. It is concluded that the heating influenced positively on the iodometric titration, as opposed to the reactive ribbon.

New Methodology for Removing Carbonyl Compounds from Sweet Wines

Sweet white wines from botrytized grapes present high SO2 levels because of their high sulfur dioxide binding power. The objective of this work was to develop a new method for reducing this binding power by partially eliminating the carbonyl compounds naturally present in these wines that are responsible for this phenomenon. A selective liquid-solid removal technique was developed. Phenylsulfonylhydrazine was selected as the best candidate for removing carbonyl compounds. Its reactivity in the presence or absence of sulfur dioxide was verified in model media containing acetaldehyde, pyruvic acid, and 2-oxoglutaric acid, some of the main carbonyl compounds responsible for the SO2 binding power of sweet wines. The scavenging function was grafted on porous polymer supports, and its efficiency was evaluated in model wines. Dependent upon the supports used, different quantities of carbonyl compounds (over 90% in some cases) were removed in a few days. The presence of sulfur dioxide delayed removal without changing its quality. The results obtained showed that the method removed carbonyl compounds efficiently and was applicable to wines at any stage in winemaking.

Reduction of PCDD/F Formation in MSWI by a Process-Integrated SO2 Cycle

PCDD/F formation in MSWI predominantly takes place by de novo synthesis in the ash deposits in the boiler. Permanently high SO2 concentrations cause sulfation of the boiler ash and the fly ash, which leads to low chloride concentrations in the ash deposits. This results in very low PCDD/F formation rates. High SO2 levels can be established in an efficient way by a process-integrated SO2 cycle, with only the SO2 generated by the combustion process being used. The S-recycling process can be supported by reducing the transfer rates of CaO particles to the flue gas by a low primary air supply. No additional source of sulfur is needed. No negative effects of the S-recycling process on the separation of other pollutants like Hg could be observed. These findings indicate that the PCDD/F emission standards can already be met upstream of the flue gas cleaning system by these primary measures only. The flue gas cleaning efforts can be reduced without changing the emission standards.

Using LC-MSMS To Assess Glutathione Levels in South African White Grape Juices and Wines Made with Different Levels of Oxygen

The effect of oxygen on the levels of glutathione, an important antioxidant, in must and wine was studied using a novel LC-MSMS method for the analysis of reduced and oxidized glutathione. This study found that the storage of grape juice at high SO2 and ascorbic acid levels at -20 degrees C did not lead to a decrease in reduced glutathione levels. The effect of varying the oxygen levels in South African white grape juices, which included a reductive treatment (less than 0.3 mg/L dissolved O2 added), a control treatment (between 1.0 and 1.5 mg/L dissolved O2 added), and an oxidative treatment (3.5-4 mg/ L dissolved O2 added, without SO2) on reduced glutathione levels in the juice and resulting wine was also investigated. A custom build press was used to press whole bunches of two different Sauvignon Blanc and Colombard grapes. Alcoholic fermentation and oxygen additions to the must led to lower reduced glutathione levels in the wine. Reduced glutathione levels were only significantly higher in the wine made from reductive juice that had the highest initial reduced glutathione levels in the grapes.

The characteristics of the air pollution of a transition economy city: The example of Belgrade

The results of sulphur dioxide (SO2), nitrogen dioxide (NO2) and black smoke (BS) levels in the Belgrade metropolitan area, the only pollutants measured at almost all 20 monitoring stations set up in the area, were critically analyzed, the most reliable ones select and the pollution characteristics were defined in these terms. Belgrade was found to have pollution typical for a city in economical transition - still high SO2 and BS levels, with seasonal variation, while moderate NO2 levels. This is discussed in terms of sources, as well as spatial and temporal distribution. .