• Journal of Environmental Health Sciences
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• v.42 no.6
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• pp.375-384
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• 2016

Objectives: This paper analyzes the intersection of tort law and environmental health in a recent court decision. Methods: This paper analyzes Supreme Court Decision 2011Da7437, Decided on September 4, 2014 and related lower court decisions. Results: The plaintiffs sought financial compensation from the defendants, arguing that air pollutants in gases emitted by vehicles produced by the defendants had caused them to acquire respiratory diseases. The district court highlighted the need to mitigate the burden of proof for the plaintiffs, but proceeded to review whether the plaintiffs proved the actual toxicity levels of the air pollutants, whether the defendant's vehicles were the main source of the emissions, the plaintiff's level of exposure to the pollutants, and causation between the emissions and the injury. By doing so, the district court required the plaintiffs to prove both indirect and direct facts of causation, increasing burden of proof for plaintiffs. The appellate court upheld the district court's decision, adding that the defendant's conduct did not constitute an illegal act because it did not violate the emissions standards set by environmental law. The Supreme Court upheld the appellate court's decision, reasoning that the epidemiological evidence cannot establish a direct causation for diseases that lack specificity. Conclusion: This case demonstrates that discussions in environmental health have significance in tort lawsuits. For each fact that the plaintiffs and defendants attempted to prove, environmental health research studies were offered as evidence. In addition, the courts decided the legality of the defendant's conduct based on emission standards set by environmental law.

• Applied Chemistry for Engineering
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• v.29 no.5
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• pp.519-523
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• 2018

Cyclodextrins are a class of oligosaccharides having an extremely low toxicity, so that they have been used for the formation of host-guest complexes and removal of toxic gases or molecules. In this study, the subtle phenomenon associated with the formation of host-guest complexes between cyclodextrin and toxic molecules (methyl paraben) was experimentally investigated. First, the formation of cyclodextrin-methyl paraben complexes was monitored by UV/Vis spectroscopy as a function of the cyclodextrin concentration. Secondly, the electrochemical measurement was performed with the surface engineered Au electrode having cyclodextrin molecules on the Au substrate. The sensing signal derived from the addition of methyl paraben solution into the Au surface was measured delicately. This study can be informative for future applications such as sensors.

• Analytical Science and Technology
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• v.16 no.3
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• pp.218-225
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• 2003

Hydrogen Chloride is among the most problematic gases used in semiconductor process. It raises serious environmental and health problems due to its extreme toxicity. This study is to develop a method to effectively remove hydrogen chloride gas during the process by using various types of inorganic gas adsorption agents, which have not been attempted in the conventional methods. The removal efficiency of the gas was both qualitatively and quantitatively measured by a FT-IR spectrophotometer. The whole device for the measurement has been designed and built in our lab. The removal efficiencies of hydrogen chloride gas were compared between those tested resins; zeolite A, modified AgA zeolite, ZnO, and $AgMnO_3$. The experimental result revealed that ZnO showed the best efficiency that had removed 0.067 g of HCl per 1 g of the resin used.

• Journal of the Korean Geotechnical Society
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• v.17 no.6
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• pp.47-51
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• 2001

There are two strategies to cope with the troubles in landfill site after closure. The first method is active in a way that the wastes are dug up and the recyclable materials are reutilized, meanwhile the materials not recyclable are incinerated in order to minimize the volume of residues to be disposed of. The second method is rather passive and defensive in a way that the source of contamination, that is, buried wastes are not treated. Instead, the transport of leaking leachate and gases generated from the wastes are intercepted and controlled. In this study, as a passive way of the efficient leachate blocking process, applicabilities of geocrete and soluble sodium silicate as a substitute to control leachate leaking from landfill sidewall were investigated. In case of compression test, the strength of mixture I (Geocrete:Sodium silicate=1:3.9 v/v) and mixture II (Geocrete:Sodium silicate=1:2.5 v/v), even after 7 days' curing was higher than the minimum allowance to tolerate the loading(5 kg/$\textrm{cm}^2$). Soaking in the acid fur 4 days and 7 days respectively, the compressive strength of the specimens reduced seriously. The toxicity of geocrete is not detected through the bioassay test, once it was mixed with sodium silicate and the complex was formed. The hydraulic conductivity of the mixtures even after 7 days' curing was lower than the threshold limit $(1.0\times10_{-7}cm/s)$.

• Applied Chemistry for Engineering
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• v.29 no.4
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• pp.413-418
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• 2018

Cypress woods treated individually with boric acid (BA4), ammonium pentaborate (APB4), or BA4/APB4 additives were examined for combustion gases. Each of the specimens was painted with a 4 wt% solution of boron compounds three times. Dried at room temperature, the combustion gas was analyzed using a cone calorimeter (ISO 5660-1). Consequently, the second maximum oxygen consumption rate of the specimen treated with boron compounds was 0.1067 to 0.1246 g/s, which was 5.3 to 18.9%, respectively lower than that of the blank specimen. The specific extinction area of specimens treated with BA4 and APB4 was also 2.0 to 19.0% lower, respectively. However, treated with BA4/APB4 showed 21.2% higher than that of the blank specimen. The maximum carbon monoxide concentration of the specimens with boron compounds was reduced by 0 to 25%. It was estimated to be 1.6 to 2.2 times higher than the permissible exposure limits by Occupational Safety and Health Administration (OSHA), indicating a fatal toxicity. The boron compounds were effective in reducing carbon monoxide, but didn't meet the OSHA limit. The boron compound inhibited the burning behavior of the cypress wood, which suppressed the second maximum oxygen consumption rate by 5.3 to 18.9% and the maximum carbon monoxide generation by 0 to 25%.

• Fire Science and Engineering
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• v.33 no.4
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• pp.16-27
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• 2019

A burning test was conducted on the smoke and combustion gases generated from cypress wood treated with sodium silicate, 3-aminopropyltrimethoxysilane sol, 3-(2-aminoethylamino)propylmethyldimethoxysilane sol, and 3-(2-aminoethylamino) propyltrimethoxysilane sol. The silicone compound sol was applied to each of the cypress wood specimens three times with a brush. The smoke and combustion generation gas were analyzed using a cone calorimeter (ISO 5660-1) and the smoke was also evaluated by applying new smoke risk assessment method. The smoke performance index (SPI) of the cypress treated with silicone compound increased 1.66 to 8.42 times and the smoke growth index (SGI) was 11.8 to 88.2%, respectively. The smoke intensity (SI) is expected to be 1.0~50.5% lower than that of the base specimens, resulting in lower smoke and fire hazards. The third maximum carbon monoxide (CO_peak) concentration of the specimens treated with silicone compounds was 22.5~33.3% lower than that of the base specimens. On the other hand, it produced potentially fatal toxicity that was 1.48~1.72 times higher than the US Occupational Safety and Health Administration (OSHA) acceptance standard (PEL). Cypress wood itself produced a high carbon monoxide concentration, but the silicon compound played a role in reducing this level.

• Journal of Aerospace System Engineering
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• v.17 no.6
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• pp.1-8
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• 2023

Research, such as developing alternative energy in the transportation field, including aviation, is being actively conducted to solve the issue of current climate change. Interest in ammonia fuel as a carbon free energy (CFE) source is increasing due to the ease of liquefaction and transportation and similarity in energy density to that of methanol. However, explosiveness and toxicity of ammonia make it difficult to handle. Therefore, in this study, stable ammonia production was attempted using relatively easy-to-handle urea water solution (UWS). High temperature steam was used to promote the hydrolysis of ammonia. In order to determine the causes for ammonia production below the theoretical equivalent ratio, it was suggested that there were not enough collisions to promote the hydrolysis based on the kinetic theory of gases. The hydrolysis of unreacted isocyanic acid (HNCO) was tested according to the change in water supply. As a result, an increased amount of ammonia produced was confirmed. The increased amount of ammonia produced in a certain section was dependent on the steam temperature and the flow rate of water supplied.

• Clean Technology
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• v.25 no.3
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• pp.256-262
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• 2019

Hydroxylammonium nitrate (HAN)-based liquid propellants are attracting attention as environmentally friendly propellants because they are not carcinogens and the combustion gases have little toxicity. The catalyst used to decompose the HAN-based liquid propellant in a thruster must have both low temperature activity and high heat resistance. The objective of this study is to prepare an Ru/alumina/metal foam catalyst by supporting alumina slurry on the surface of NiCrAl metal foam using a washing coating method and then to support a ruthenium precursor thereon. The decomposition activity of a HAN aqueous solution of the Ru/alumina/metal foam catalyst was evaluated. The effect of the number of repetitive coatings of alumina slurry on the physical properties of the alumina/metal foam was analyzed. As the number of alumina wash coatings increased, mesopores with a diameter of about 7 nm were well-developed, thereby increasing the surface area and pore volume. It was optimal to repeat the wash coating alumina on the metal foam 12 times to maximize the surface area and pore volume of the alumina/metal foam. Mesopores were also well developed on the surface of the Ru/alumina/metal foam catalyst. It was found that the metal form itself without the active metal and alumina can promote the decomposition reaction of the HAN aqueous solution. In the case of the Ru/alumina/metal foam-550 catalyst, the decomposition onset temperature was significantly lowered compared with that of the thermal decomposition reaction, and ${\Delta}P$ could be greatly increased in the decomposition of the HAN aqueous solution. However, when the catalyst was calcined at $1,200^{\circ}C$, the catalytic activity was lowered inevitably because the surface area and pore volume of the catalyst were drastically reduced and Ru was sintered. Further research is needed to improve the heat resistance of Ru/alumina/metal foam catalysts.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1972.03a
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• pp.6-7
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• 1972

The air pollutants can be classified into the irritant gas and the asphixation gas, and the irritant gas is closely related to the otorhinolaryngological diseases. The common irritant gases are nitrogen oxides, sulfur oxides, hydrogen carbon compounds, and the potent and irritating PAN (peroxy acyl nitrate) which is secondarily liberated from photosynthesis. Those gases adhers to the mucous membrane to result in ulceration and secondary infection due to their potent oxidizing power. 1. Sulfur dioxide gas Sulfur dioxide gas has the typical characteristics of the air pollutants. Because of its high solubility it gets easily absorbed in the respiratory tract, when the symptoms and signs by irritation become manifested initially and later the resistance in the respiratory tract brings central about pulmonary edema and respiratory paralysis of origin. Chronic exposure to the gas leads to rhinitis, pharyngitis, laryngitis, and olfactory or gustatory disturbances. 2. Carbon monoxide Toxicity of carbon monoxide is due to its deprivation of the oxygen carrying capacity of the hemoglobin. The degree of the carbon monoxide intoxication varies according to its concentration and the duration of inhalation. It starts with headache, vertigo, nausea, vomiting and tinnitus, which can progress to respiratory difficulty, muscular laxity, syncope, and coma leading to death. 3. Nitrogen dioxide Nitrogen dioxide causes respiratory disturbances by formation of methemoglobin. In acute poisoning, it can cause pulmonary congestion, pulmonary edema, bronchitis, and pneumonia due to its strong irritation on the eyes and the nose. In chronic poisoning, it causes chronic pulmonary fibrosis and pulmonary edema. 4. Ozone It has offending irritating odor, and causes dryness of na sopharyngolaryngeal mucosa, headache and depressed pulmonary function which may eventually lead to pulmonary congestion or edema. 5. Smog The most outstanding incident of the smog occurred in London from December 5 through 8, 1952, because of which the mortality of the respiratory diseases increased fourfold. The smog was thought to be due to the smoke produced by incomplete combustion and its byproduct the sulfur oxides, and the dust was thought to play the secondary role. In new sense, hazardous is the photochemical smog which is produced by combination of light energy and the hydrocarbons and oxidant in the air. The Yonsei University Institute for Environmental :pollution Research launched a project to determine the relationship between the pollution and the medical, ophthalmological and rhinopharyngological disorders. The students (469) of the "S" Technical School in the most heavily polluted area in Pusan (Uham Dong district) were compared with those (345) of "K" High School in the less polluted area. The investigated group had those with subjective symptoms twice as much as the control group, 22.6% (106) in investigated group and 11.3% (39) in the control group. Among those symptomatic students of the investigated group. There were 29 with respiratory symptoms (29%), 22 with eye symptoms (21%), 50 with stuffy nose and rhinorrhea (47%), and 5 with sore thorat (5%), which revealed that more than half the students (52%) had subjective symptoms of the rhinopharyngological aspects. Physical examination revealed that the investigated group had more number of students with signs than those of the control group by 10%, 180 (38.4%) versus 99 (28.8%). Among the preceding 180 students of the investigated group, there were 8 with eye diseases (44%), 1 with respiratory disease (0.6%), 97 with rhinitis (54%), and 74 with pharyngotonsillitis (41%) which means that 95% of them had rharygoical diseases. The preceding data revealed that the otolaryngological diseases are conspicuously outnumbered in the heavily polluted area, and that there must be very close relationship between the air pollution and the otolaryngological diseases, and the anti-pollution measure is urgently needed.