Determination of the Spatial Distribution of Air Pollutants in Bucheon, Republic of Korea, in Winter Using a GIS-Based Mobile Laboratory.

Driven by industrialization and urbanization, urban air pollution can increase respiratory, heart, and cerebrovascular diseases, and thus mortality rates; as such, it is necessary to improve air quality through the consideration of individual pollutants and emission sources. In Republic of Korea, national and local governments have installed urban and roadside air quality monitoring systems. However, stations are lacking outside metropolitan regions, and roadside stations are sparsely distributed, limiting comparisons of pollutant concentrations with vehicle traffic and floating population levels. Local governments have begun using mobile laboratories (MLs) to supplement the fixed measurement network and investigate road pollution source characteristics based on their spatiotemporal distribution; however, the collected data cannot be used effectively if they are not visualized. Here, we propose a method to collect and visualize global information system (GIS)-based air quality data overlayed with environmental variables to support air quality management measures. Spatiotemporal analyses of ML-derived data from Bucheon, Korea, confirmed that particulate and gaseous pollutant concentrations were high during typical commuting hours, at intersections, and at a specially managed road. During commuting hours, the maximum PM10 concentration reached 200.7 µg/m3 in the Nae-dong, Gyeongin-ro, and Ojeong-dong ready-mix concrete complex areas, and the maximum PM2.5 concentration was 161.7 µg/m3. The maximum NOx, NO2, and NO levels of 1.34 ppm, 0.18 ppm, and 1.18 ppm, respectively, were also detected during commuting hours. These findings support the need for targeted management of air pollution in this region, and highlight the benefit of comprehensively comparing road levels, driving speed, and traffic levels when identifying hotspots of air pollution. Such analyses will contribute to the development of air quality management measures customized to regional characteristics.

Pharmacokinetic and Pharmacodynamic Characteristics of Pelubiprofen Tromethamine vs. Pelubiprofen in Healthy Subjects.

Compared to pelubiprofen, a cyclooxygenase-2-selective inhibitor, pelubiprofen tromethamine has been reported to exhibit improved solubility and absorption. Pelubiprofen tromethamine combines the anti-inflammatory effect of pelubiprofen with the gastric protective function of tromethamine salt, making it a relatively safe class of non-steroidal anti-inflammatory drugs with low levels of gastrointestinal side effects in addition to its original analgesic, anti-inflammatory, and antipyretic effects. This study assessed the pharmacokinetic and pharmacodynamic characteristics of pelubiprofen and pelubiprofen tromethamine in healthy subjects. Two independent clinical trials were performed in healthy subjects using a randomized, open-label, oral, single-dose, two-sequence, four-period, crossover design. In Study I and Study II, subjects received 25 mg of pelubiprofen tromethamine and 30 mg of pelubiprofen tromethamine, respectively, with 30 mg of pelubiprofen being the reference. Study I fell within the bioequivalence study criteria. A trend of increased absorption and exposure for 30 mg of pelubiprofen tromethamine vs. the reference in Study II was observed. The maximum cyclooxygenase-2 inhibitory effect of 25 mg of pelubiprofen tromethamine was approximately 98% compared to the reference, showing no significant pharmacodynamic variation. It is thus predicted that 25 mg of pelubiprofen tromethamine would show no clinically significant discrepancies in clinical analgesic and antipyretic effects from 30 mg of pelubiprofen.

A New Method of Removing Fine Particulates Using an Electrostatic Force.

Many studies have found that the concentration of fine particulates in the atmosphere has increased. In particular, when using the bus, the situation in which people are exposed to relatively high concentrations of fine particulates is increasing. The purpose of this study is to reduce exposure to these potentially harmful particulates by introducing open shelters at outdoor bus stops. In order to use it as an outdoor fine particulates reduction device, a brush filter using electrostatic force (EF) was used on an experimental scale and the generation of electrostatic force, according to the material, was examined. As electrostatic force was generated, the fine particulates collection performance was about 90% efficiency. In addition, it was confirmed that the efficiency of each particle size was improved by 57% through structural improvement. Finally, through experimentation, it was confirmed that the brush module can be used for about 70 days.

A UAV-Based Air Quality Evaluation Method for Determining Fugitive Emissions from a Quarry during the Railroad Life Cycle.

Gravel is used in railway infrastructure to reduce environmental impacts and noise, but gravel on tracks must be replaced continuously because it deforms due to wear and weathering. It is therefore necessary to review the entire railroad life cycle. In this study, an unmanned aerial vehicle (UAV) was used to measure resuspended dust over a wide area. The dust was generated from transport movements in relation to the operation of a quarry, which represents the first stage of the railway life cycle. The dust was measured at Gangwon-do quarry using a Sniffer4D module, which can provide measurements at 1 s intervals through a light scattering method and has high reliability (R2 = 0.95 for PM2.5, R2 = 0.88 for PM10). The hourly generation of fugitive dust was calculated as 2937.5 g/h for PM2.5 and 4293.2 g/h for PM10. The social cost of dust generation was calculated as KRW 36.59 billion. The amount of dust generated per hour at the quarry was ~12 times greater than that generated by the operation of a regulator as a maintenance vehicle, with the largest amount of fugitive dust generated by the washing-type vehicle. This is the first study to measure the amount of fugitive dust generated in real time at 1 s intervals by monitoring the first stage of the railroad life cycle over a wide area using a Sniffer4D module attached to a UAV. This method can be replicated for use in various studies.

Determination of the Optimum Removal Efficiency of Fine Particulate Matter Using Activated Carbon Fiber (ACF).

In Korea, concentrations of particulate matter (PM10) are significantly higher in urban railway tunnels (178.1 µg/m3) than in metropolitan areas (49 µg/m3). In railway tunnels in Korea, it was maintained at 3-4 times higher concentration than general atmosphere and platform. Dust generated by trains is scattered at high speed in these tunnels, making filtration difficult; therefore, the development of filters that can be maintained in tunnels is required. In the present study, we examined PM adsorption in the laboratory scale using activated carbon fiber (ACF), which has high adsorption and capacity. The ACF depth, velocity of flow, and fine PM concentration in the tunnel were the experimental variables. We compared PM concentrations before and after the filter experiments, and calculated removal efficiency to determine the optimal conditions. Comprehensive examination of the experimental variables and differential pressure showed that the optimal conditions for an ACF specimen were a wind speed of 3.0 m/s and the ACF depth of 400 mm. The average removal efficiency of PM10 was 55.5%, and that of PM2.5 was 36.6%. The reproducibility tests showed that the ACF filter could be washed and reused and is suitable for various places because it is easily maintained.

Characteristics of exposure factors and inhalation exposure to selected spray consumer products in Korean population.

Many consumer spray products are sold for various purposes. Use of spray products can cause adverse health effects. This study evaluated exposure factors for consumer spray products and assessed the particle inhalation exposure. Six consumer spray products were evaluated: an automobile interior cleaner, car deodorizing spray, anti-static spray, waterproofing spray, microorganism deodorizer, and disinfectant spray. The exposure factors were based on 10,000 respondents over 15 years old. Inhalation dose was calculated from the concentration released into the room air and time used. The use rates of the spray products ranged from 0.4 to 11% and differed significantly by gender (p < 0.001). Aerosol types had a higher mass per use and longer duration of usage than trigger types. The median concentration of the trigger type ranged from 17.35 to 373.38 mg/m3, while that of the aerosol type ranged from 36.66 to 1601.97 mg/m3. The median inhalation dose of the trigger and aerosol types ranged from 2.04 × 10-3 to 0.20 and 2.60 × 10-3 to 1.71 mg/kg/day, respectively. The inhalation dose of the disinfectant spray increased with the level of education (p < 0.001), while the inhalation doses of the other spray products were not significantly associated with gender, age, income, or education.