• Journal of Environmental Science International
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• v.3 no.3
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• pp.253-261
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• 1994

Chloroform present in the swimming water disinfected with sodium hypochlorite is released to the air of swimming pools. The air chloroform concentrations were measured in two swimming pools A and B which applied both sodium hypochlorite a:d ozone. Thew mean concentrations are 28.0 $\mu\textrm{g}$/m3 and 33.6 $\mu\textrm{g}$/m3in the swimming pools A and B, respectively. On the other hand, the mean water chloroform concentrations in the swimming pools A and B were 23.9 $\mu\textrm{g}$/l and 19.5 $\mu\textrm{g}$/l, respectively. The air chloroform concentrations were lower in the swimming Bools A and B than those reported by previous studies abroad employed the swimming pools which applied sodium hypochlorite only for water disinfection. The water chloroform concentrations were also lower in this study than in the previous studies. The relationship between the air and water chloroform concentrations measured in this study was significant with p=0.002 and Rz=0.42. At similar time to the indoor air sampling, outdoor air samples were collected at two sites near each of the swimming Pools A and B. The mean outdoor air chloroform concentrations near the swiminE Pools A and B were 0.41 $\mu\textrm{g}$/m3 and 0.16 $\mu\textrm{g}$/m3, respectively. The outdoor air chloroform concentrations measured in this study were equal to or lower than those reported by previous studies abroad. 'rho chloroform dose inhaled for a typical one-hour swim was estimated to be 25.9 $\mu\textrm{g}$ per person, corresponding to a specific 0.37 $\mu\textrm{g}$/kg body weight for a reference 70 Kg male adult, while the inhalation dose of chloroform from the outdoor air was estimated to be 5.6 $\mu\textrm{g}$ per person per day, corresponding to a specific 0.08 $\mu\textrm{g}$/Kg/day for the same reference male adult.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.12
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• pp.1323-1330
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• 2006

In this study, five different odor causing compounds in the Nakdong river and rapid sand filtered waters were treated by oxidation from $O_3/H_2O_2$ process. In addition, the change in BDOC formation by the $O_3/H_2O_2$ process was also investigated for considering this advanced oxidation Process as a pre-treatment to the BAC treatment process. The experimental result showed that the removal efficiency of geosmin was higher with the use of 5 mg/L of $O_3$ and 0.2 mg/L of $H_2O_2$ than with the use of 20 mg/L of $O_3$ alone for the sand filtered water. And in general, the removal efficiency of geosmin in raw water was $12{\sim}27%$ lower than the one in sand filtered water. In sand filtered water. the removal efficiencies of geosmin and IPMP decreased when $H_2O_2/O_3$ ratio increases above the optimum ratio. The optimum ratio of $H_2O_2/O_3$ dose was $0.5{\sim}1.0$ for geosmin and $0.2{\sim}1.0$ for IPMP. However, the optimum ratio of $H_2O_2/O_3$ in raw water remove geosmin appealed to $1.0{\sim}3.0$. According to the experimental results for the removal of 5 different odor causing compounds under varied $O_3$ doses, the removal efficiency of IPMP was the highest with 60% and, in overall, $O_3/H_2O_2$ process showed higher removal efficiency than $O_3$ alone process. The BDOC formation by the $O_3/H_2O_2$ process increased from $0.1{\sim}0.25$ to $0.19{\sim}0.34$ comparing to $O_3$ process alone. Therefore, it is concluded that the advanced oxidation process with $O_3/H_2O_2$ can be used as a pretreatment to the BAC treatment process.

• Journal of Applied Biological Chemistry
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• v.61 no.4
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• pp.417-421
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• 2018

Ultraviolet rays are electromagnetic waves with a shorter wavelength than visible light, and ultraviolet rays that pass through the ozone layer are the main cause of skin aging. Chronic exposure of skin tissue to ultraviolet light activates the Mitogen-activated Protein Kinases (MAPKs) signaling pathways in human keratinocytes, resulting in increased production of matrix metalloproteinases (MMPs). In this study, we investigated the herbal extracts from Jeju Island on the anti-aging effect in human keratinocytes (HaCaTs) by ultraviolet stimulation. We examined that herb extract from Jeju Island were decreased in anti-aging activity on measuring the level of MMP-1 gene and protein expression in ultraviolet-induced keratinocytes. As a result, it was confirmed that Thymus quinquecostatus extract (TQE) significantly reduced the expression of MMP-1 in a dose-dependent manner by UV irradiated HaCaTs. According to our data, TQE significantly attenuated UV-induced phosphorylation of the MAPKs signaling elements ERK1/2, JNK1/2 and p38 proteins. These results suggest that the MAPKs pathway may contribute to the inhibitory effect of TQE on UV-induced MMP-1 production in human keratinocytes. Our results suggest that TQE may be a protective agent against skin aging by preventing UV-induced MMP-1 production.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.12
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• pp.1781-1786
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• 2011

This study was conducted to investigate the cause of microbiological contamination in yogurt and evaluate the effect of physicochemical treatment on the growth inhibition of Hanseniaspora uvarum isolated from yogurt. The yeast strain Hanseniaspora uvarum Y1 was subjected to heat and pH treatments. H. uvarum Y1 was killed at $70^{\circ}C$ and $80^{\circ}C$ after 15 min and survived in a wide pH range from pH 2 to 9. However, it did not survive under pH 1 and over pH 10. In a disk diffusion susceptibility test on H. uvarum Y1, a clear zone (5 mm) of growth inhibition was observed upon treatment with electrolyzed water. The effect of ozone gas on the growth of H. uvarum Y1 was evaluated by viable cell count. Initial cell numbers of $10^2$ and $10^3$ CFU/mL of H. uvarum Y1 were completely killed by treatment for 10 and 30 min, respectively. H. uvarum Y1 was also sterilized by microwave treatment for 1 min. When treated with gamma-irradiation, the rate of killing of H. uvarum Y1 was proportional to the irradiation dose. and complete killing occurred at a dose of 50 kGy.