title: Distributions of SO2and NO2in the lower atmosphere of an industrial area in Bhutan.
abstract: Two important air pollutants, sulfur dioxide (SO2) and nitrogen dioxide (NO2), were sampled and monitored in the spring season in the biggest industrial area of Bhutan. Field measurements of SO2and NO2were performed using standard colorimetric methods, and air samples were collected using an active sampling technique. Sampling sites were selected to cover all the potential catchment areas like settlements, staff quarters, shops and schools. The main objective of this sampling work was to see the distribution of these two pollutants from the source of emission (small scale industries) and to obtain and establish a baseline data. The active sampler was first tested and validated in a laboratory using liquid and gas standards of SO2and NO2. Good linearity from 0.050 to 1.0 µg mL-1for SO2and from 0.010 to 1.0 µg mL-1for NO2were obtained (R2> 0.99) with limits of detection of 30 and 50 ng mL-1for SO2and NO2, respectively. Daylong sampling was done at selected sites with a range of distances away from the sources of emission. The ambient concentration of SO2and NO2were in the range of 0.45-4.46 and 0.56-5.68 µg m-3, respectively.
authors.affiliation: a Trace Analysis and Biosensor Research Center, Prince of Songkla University , Hat Yai, Songkhla , Thailand.|b Department of Chemistry , Faculty of Science, Prince of Songkla University , Hat Yai, Songkhla , Thailand.
authors.forename: Jas Raj
authors.initials: JR
authors.lastname: Subba
authors.affiliation: a Trace Analysis and Biosensor Research Center, Prince of Songkla University , Hat Yai, Songkhla , Thailand.|b Department of Chemistry , Faculty of Science, Prince of Songkla University , Hat Yai, Songkhla , Thailand.
authors.forename: Chongdee
authors.initials: C
authors.lastname: Thammakhet
authors.affiliation: a Trace Analysis and Biosensor Research Center, Prince of Songkla University , Hat Yai, Songkhla , Thailand.|c Department of Physics , Faculty of Science, Prince of Songkla University , Hat Yai, Songkhla , Thailand.
authors.forename: Panote
authors.initials: P
authors.lastname: Thavarungkul
authors.affiliation: a Trace Analysis and Biosensor Research Center, Prince of Songkla University , Hat Yai, Songkhla , Thailand.|b Department of Chemistry , Faculty of Science, Prince of Songkla University , Hat Yai, Songkhla , Thailand.
authors.forename: Proespichaya
authors.initials: P
authors.lastname: Kanatharana
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D001631:Bhutan; D004784:Environmental Monitoring; D007221:Industry; D009585:Nitrogen Dioxide / Q000032:analysis*; D012621:Seasons; D013458:Sulfur Dioxide / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D013458:Sulfur Dioxide; D009585:Nitrogen Dioxide
keywords: Active sampler; Bhutan; baseline data; nitrogen dioxide; sulfur dioxide