In the study, pollution levels of indoor polycyclic aromatic hydrocarbons (PAHs) in public facilities (vapor phase or particulate phase) were evaluated, and a health risk assessment (HRA) was carried out based on exposure scenarios. Public facilities in Korea covered by the law, including underground subway stations, funeral halls, child care facilities, internet cafes (PC-rooms), and exhibition facilities (6 locations for each type of facility, for a total of 48 locations), were investigated for indoor assessment. For the HRA, individual excess cancer risk (ECR) was estimated by applying main toxic equivalency factor (TEF) values suggested in previous studies. Among the eight public facilities, internet cafes showed the highest average PM 2.5 concentration at 110.0 μg/m 3 (range: 83.5-138.5 μg/m 3

Emissions of volatile organic compounds (VOCs) and carbonyls from three types of commercially available wallpapers (i.e., PVC-coated, paper-backed, natural material-coated) in Korea were evaluated using a 20 L small chamber. A total of 332 products were tested for emission factors, frequencies of occurrence and composition ratios. Toluene and formaldehyde concentrations were below Korean standard values for all products; however, the total VOC (TVOC) concentrations exceeded current standards (4.0 mg/m2·h) for 30 products. The TVOC emission factor for PVC-coated wallpapers, for which polymer materials are used in the manufacturing process, was seven and 16 times higher than those of paper-backed and natural material-coated wallpapers, respectively. The detection frequencies for toluene and formaldehyde were the highest (82.5%) and fourth highest (79.5%), respectively among the 50 target chemical species. The composition ratios for BTEX ranged from 0.3% to 5.1% and unidentified VOCs, which were not qualitatively analyzed using standard gas methods, ranged from 90.2% to 94.8%. Among six carbonyl compounds (acrolein was not detected in any type of wallpaper), acetone had the highest concentrations in PVC-coated (44.6%) and paper-backed (66.6%) wallpapers. Formaldehyde emissions were highest (64.6%) for natural material-coated wallpapers, a result of the formaldehyde-based resin used in the manufacturing process for these products.

The purpose of the study is to evaluate the pollution level (gaseous and particle phase) in the public facilities for the PAHs, non-regulated materials, forecast the risk level by the health risk assessment (HRA) and propose the guideline level. PAH assessments through sampling of particulate matter of diameter ⁄ ⁄2.5 μm (PM 2.5 ). The user and worker exposure scenario for the PAHs consists of 24-hour exposure scenario (WIES) assuming the worst case and the normal exposure scenario (MIES) based on the survey. This study investigated 20 PAH substances selected out of 32 substances known to be carcinogenic or potentially carcinogenic. The risk assessment applies major toxic equivalency factor (TEF) proposed from existing studies and estaimates individual Excess Cancer Risk (ECR). The study assesses the fine dusts (PM 2.5 ) and the exposure levels of the gaseous and particle PAH materials for 6 spots in each 8 facility, e.g. underground subway stations, child-care facilities, elderly care facilities, super market, indoor parking lot, terminal waiting room, internet café (PCrooms), movie theater. For internet café (PC-rooms) in particular, that marks the highest PM 2.5 concentration and the average concentration of 10 spots (2 spots for each cafe) is 73.3 μg/m 3 (range: 6.8-185.2 μg/m 3 ). The high level of PM 2.5 seen in internet cafes was likely due to indoor smoking in most cases. For the gaseous PAHs, the detection frequency for 4-5 rings shows high and the elements with 6 rings shows low frequency. For the particle PAHs, the detection frequency for 2-3 rings shows low and the elements with 6 rings show high frequency. As a result, it is investigated that the most important PAHs are the naphthalene, acenaphthene and phenanthrene from the study of Kim et al. (2013) and this annual study. The health risk assessment demonstrates that each facility shows the level of 10 --6 -10 --4 . Considering standards and local source of pollution levels, it is judged that the management standard of the benzo (a)pyrene, one of the PAHs, shall be managed with the range of 0.5-1.2 ng/m 3 . Smoking and ventilation were considered as the most important PAHs exposure associated with public facility PM 2.5 . This study only estimated for inhalation health risk of PAHs and focused on the associated cancer risk, while multiple measurements would be necessary for public health and policy.

Although experiments on intratracheal intubation for animals are essential for research, it remains challenging. This study aimed to validate an animal model using a flexible imaging guide system that can be conveniently and safely used as a new method to provide easy access to organs in small animals. PBS (Phosphate Buffered Saline) and PHMG (Polyhexamethylene guanidine) were administered by intratracheal intubation to 20 rodents (10 mice and 10 rats), and the changes in the lungs were observed. Results were verified using lung tissue histopathologic staining through the intratracheally administered material, which confirmed that 100% of changes in lung tissue occurred in the PHMG-injected group, where intubation was facilitated using the flexible imaging guide. The drug was conveniently and safely administered. The flexible-imaging-fiber-guide-based intratracheal drug injectable system may be conveniently used by researchers. It allows drugs to be administered quantitatively, suggesting its potential wide use in drug development and toxicity evaluation.

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