BACKGROUND In asthmatic subjects bronchoconstriction is induced by inhalation of the common food preservatives sulphur dioxide (SO2) and metabisulphite (MBS). SO2 and MBS challenges share many similarities, but it is not known whether they are equivalent. In this study of subjects with mild clinical asthma equivalence was assessed by comparing SO2 and MBS reactivity by estimating the total dose...

We compared the effect of inhaled NO2 and SO2 on airway tone and airway responsiveness in 14 nonsmoking mild asthmatics (mean +/- SD age 34 +/- 14 yrs; mean +/- SD baseline forced expiratory volume in one second (FEV1), 86 +/- 17% pred). On 3 separate days, 30 min tidal breathing (average minute ventilation 10.6 l.min-1) of either filtered air, 0.25 ppm NO2, or 0.5 ppm SO2 was followed by an is...

Stratospheric aerosols (SAs) are a variable component of the Earth’s albedo that may be intentionally enhanced in the future to offset greenhouse gases (geoengineering). The role of tropospheric-sourced sulfur dioxide (SO2) in maintaining background SAs has been debated for decades without in situ measurements of SO2 at the tropical tropopause to inform this issue. Here we clarify the role of S...

Sulfur dioxide (SO2) is a major air pollutant, especially in developing countries. Many trees are seriously impaired by SO2, while other species can mitigate air pollution by absorbing this gas. Planting appropriate tree species near industrial complexes is critical for aesthetic value and pollution mitigation. In this study, six landscape tree species typical of a subtropical area were investi...

We implement the Predicting Particles Produced in Power-Plant Plumes (P6) sub-grid sulphate parameterization for the first time into a global chemical-transport model with online aerosol microphysics, the GEOS-Chem-TOMAS model. Compared to simulations using two other previous treatments of sub-grid sulphate, simulations using P6 subgrid sulphate predicted similar or smaller increases (depending...

Stratospheric aerosols (SAs) are a variable component of the Earth's albedo that may be intentionally enhanced in the future to offset greenhouse gases (geoengineering). The role of tropospheric-sourced sulfur dioxide (SO2) in maintaining background SAs has been debated for decades without in-situ measurements of SO2 at the tropical tropopause to inform this issue. Here we clarify the role of S...

The simultaneous removal of SO2/NO2 by limestone slurry was studied in a gas-liquid bubbling reactor. Experiments were carried out to find the effect of various operating parameters such as inlet concentration of SO2 and NO2, reaction temperature, O2 content in the flue gas and additive on the SO2 and NO2 removal efficiencies. SO2 removal efficiency decreased with inlet NO2 concentration, react...

Sulfur dioxide (SO2) is a gaseous environmental pollutant which is routinely used in industry as a preservative and antimicrobial. Recent data suggests that SO2 may have value as a therapeutic agent. However, due to its gaseous nature, localizing SO2 generation is challenging. Herein, various 1,3-dihydrobenzo[c]thiophene 2,2-dioxides (benzosulfones) were prepared as candidates for photochemical...

In the whole world, most of air polluted cities were normalized during COVID-19 lockdown but after lockdown, pollution is continuously increasing day by day. present study, we assessed quality at selected sites Jaipur city from October 2020 to February 2021 quantify enhancement in pollution. The obtained data was processed using index (AQI), principal component analysis (PCA) and pearson correl...

[1] Pinatubo’s 15 June 1991 eruption was Earth’s largest of the last 25 years, and it formed a substantial volcanic cloud. We present results of analysis of satellite-based infrared remote sensing using Advanced Very High Resolution Radiometer (AVHRR) and TIROS Operational Vertical Sounder/High Resolution Infrared Radiation Sounder/2 (TOVS/HIRS/2) sensors, during the first few days of atmospher...