• Journal of Korean Society of Environmental Engineers
• /
• v.29 no.2
• /
• pp.214-219
• /
• 2007

66 micropollutants analyses in 9 wastewater treatment plants(WWTPs) along Nak-dong river were implemented to identify the concentrations and removal efficiencies before and after treatment processes. As a result of study, the concentration levels discharged from WWTP effluents to water system were below the water quality criteria and the levels of other studies. The removal efficiencies were 84.6%(DAF/CCR) and 81.6%(AC) for 1,4-dioxane. Phenol, Clphs and PAHs were removed 94.6%, 66.4% and 80.6% respectively by the activated sludge(AS) process. The removal efficiencies of Clbzs were 45.3% for the activated sludge(AS) process and 60.6% for the activated carbon(AC) process. However, other processes besides AS and AC, the removal efficiencies of Clbzs were very low(<20%). The sand filtration(SF) process that could remove particle matters showed the best efficiency for PCDDs / Fs removal$(\geq99%)$. However, in case of relatively low PCDDs/Fs concentration level in influent, the removal efficiency was not so high$(\leq50%)$.

• Analytical Science and Technology
• /
• v.11 no.5
• /
• pp.321-331
• /
• 1998

The separation and sample extraction methods of 19 polycyclic aromatic hydrocarbons (PAHs) in water samples were investigated by gas chromatography/mass spectrometry (GC/MS) and some extraction methods involved liquid-liquid extraction, disk extraction and solid-phase extraction methods. The separation of 19 PAHs was possible by partial variation of oven temperature of GC/MS in temperature range $80{\sim}310^{\circ}C$. Extraction procedures of PAHs in water samples were somewhat modified and compared as extraction recoveries and the simplicity of methods. Extraction recoveries of PAHs were 71.3~109.5% by liquid-liquid extraction method. By using disk extraction, good extraction recoveries (80.7~94.9%) were obtained in case of $C_{18}$ disk extraction method by filtration. And extraction recoveries of PAHs by $C_{18}$ solid-phase were in the range of 51.8~77.9%. Method detection limits (S/N=5) of 19 PAHs were in the range of 0.25~6.25 ppb by liquid-liquid extraction and solid-phase extraction and 0.05~1.25 ppb by disk extraction methods.

• Analytical Science and Technology
• /
• v.27 no.4
• /
• pp.201-212
• /
• 2014

Polycyclic aromatic hydrocarbons (PAHs) that are carcinogenic and persistent will be restricted in consumer products from December 27, 2015 by EU REACH regulation. Pretreatment using Soxhlet extraction and quantitative analysis by GC-MS were studied to develop the method for analyzing 18 PAHs in consumer products as well as to detect the amounts and the kinds of PAHs in consumer products such as grips of a bag and a hammer, a cable and a plastic sandal. Linearity and precisions were evaluated by analyses of the standard PAH solutions ranging from 0.3125 mg/L to 5.00 mg of each of 18 PAHs. Linearity of resulting standard curves for all 18 PAHs were obtained with $R^2$ above 0.999. Precisions of the retention times and the peak areas were found to be 0.00%~0.05% and 1.16%~3.69% of relative standard deviations, respectively. The recoveries for spiked samples were all around 95%~105% after Soxhlet extration using three different solvents such as dichloromethane, hexane and toluene. The limits of quantitation for 18 PAHs in solutions and polymer samples by GC-MS were evaluated to be 0.327 mg/L (Benzo[ghi]perylene)~0.464 mg/L (Acenaphthylene) and 1.635 mg/kg (Benzo[ghi]perylene)~2.32 mg/kg (Acenaphthylene) based upon dilution factor of 5, respectively. Under the developed analytical method, only trace amounts of phenanthrene were detected in three samples while 15 kinds of PAHs including phenanthrene were detected in a grip of hammer with concentrations of maximum 83.4 mg/kg of Phenanthrene and minimum 8.5 mg/kg of Acenaphthylene. Further studies are needed to decrease the quantitation limit and to check the feasibility of decreasing Soxhlet time as well as to demonstrate cases that the clean up is required.

• Journal of Korean Society for Atmospheric Environment
• /
• v.24 no.2
• /
• pp.133-142
• /
• 2008

Five intensive measurements of particulate PAHs were made at a roadside in Seoul from May 2005 to June 2006. The average concentration of particulate PAHs was $15.1{\pm}10.6ng\;m^{-3}$. The high concentrations of particulate fluoranthene and pyrene were observed in November 2005 due to the influence of the lower ambient temperature. Compared to the previous results at tunnel and ambient sites in Seoul, larger fraction of the high molecular PAH compounds which consist with five or six benzene rings, was observed at a roadside. This might indicate high influence of vehicle emission at a roadside. The distribution of diagnostic ratios for specific PAH compounds indicated that the influence of vehicular emission, especially diesel vehicular emission seems to be high at a roadside.

• Journal of Korean Society of Environmental Engineers
• /
• v.27 no.3
• /
• pp.273-279
• /
• 2005

The degradation of o-chlorophenol(o-CP) in the presence of NaOH and the byproducts formed were investigated in a supercritical water(SCW) destruction process. The conversion of o-CP in the absence of NaOH was less than 20%, however it showed 100% conversion in the presence of NaOH(mole ratio[NaOH]/[o-CP] over than 2) with a residence time of less than 1 second. The formation of PAHs and the phenolic compounds formed were decreased in the presence of NaOH. The results revealed that the formation of byproducts during the destruction of o-CP in SCW was effected by the addition of NaOH. Phenol, cresols, chlorinated phenols, PAHs, p,p'-dihydroxybiphenyl and oxygenated polyaromatic compounds such as 1-indanone, dibenzofuran and dibenzo-p-dioxin were detected in both conditions(presence and absence of NaOH). At the same time, in the presence of NaOH, 2-ethylphenol, o-hydroxyacetophenone, hydroquinone, 4-allylphenol, 3-phenoxyphenol and 4,4'-oxybisphenol were also detected. The observed results suggest that the destruction of o-CP in SCW with NaOH occurs through a number of complicated reaction pathways. Dibenzofuran and dibenzo-p-dioxin were also detected during destruction of o-CP by SCW. The above observation suggests that there may be a common relationship between the thermal incineration process and SCW decomposition process.

• Journal of the Korean Wood Science and Technology
• /
• v.34 no.4
• /
• pp.22-30
• /
• 2006

The volatile organic compound (VOC) Analyzer is a portable device to measure the four main aromatic hydrocarbon gases: toluene, ethylbenzene, xylene and styrene. With the VOC Analyzer, a semiconductor gas sensor eliminates the need for the carrier gas which is required for conventional gas chromatographs. In addition, since the semiconductor gas sensor is supersensitive to gas components, it is not necessary to use a conventional gas concentrator or other complicated equipment. Compared with other measurement methods, the VOC analyzer is useful for measuring toluene, ethylbenzene, xylene and styrene in wood-based panel because of its ease in obtaining field results and repeating the test. The VOC Analyzer primarily measures four VOC in the air. In this study, we designed a test method of VOC measurement for particle board. A specimen was sealed in 3L polyester bag, after 96hours we could measure maximum VOC emission level that is a stabilized VOC Value. For easy, fast and economic testing of TVOC emission from wood-based panel, we developed the test method with the VOC Analyzer. The VOC Analyzer is expected to gain widespread use in the manufacturing field where a quick and easy test for VOC emission from wood-based panel is required. Furthermore, the VOC Analyzer promises to become an easier, faster and more economic technique than the currently used standard methods.

• Korean Journal of Microbiology
• /
• v.43 no.4
• /
• pp.273-278
• /
• 2007

As a model compound of PAHs (polycyclic aromatic hydrocarbons) phenanthrene has been regarded as a toxic material, mutagen and carcinogen in various animals. Biodegradation conditions of phenanthrene such as pH, temperature, shaking speed, stabilizer and cofactor of degrading enzymes were investigated with Trametes versicolor and its transformant T. versicolor MrP1 in YMG medium, minimal medium and soil microcosm. T. versicolor MrP1 can overexpress mrp gene encoding Mn-repressed peroxidase that is involved in fungal degradation. Biodegradations of phenanthrene by T. versicolor and T. versicolor MrP1 were optimally performed in conditions of weak-acid (pH 6.0), $30^{\circ}C$, shaken culture and medium containing 5 mM veratryl alcohol or tryptophan. In these optimal conditions, biodegradation of phenanthrene by T. versicolor MrP1 is 31% higher than that of wild type strain in a minimal medium for 20 days. Biodegradation of phenanthrene by T. versicolor MrP1 was also higher than that of wild type in soil microcosm. T. versicolor MrP1 can be a excellent candidate for the bioremediation of PAHs contaminated environments.

• Applied Chemistry for Engineering
• /
• v.7 no.1
• /
• pp.67-74
• /
• 1996

The binary phase equilibrium experiments of carbon dioxide/1,2,3,4 ${\alpha}$-tetrahydro-1-naphthol(${\alpha}$-tetralol) system were conducted to get phase equilibrium and mixture density data at 313.2K, 343.2K and 373.2K and within pressure ranges of 6.0 MPa to 35.0MPa. The phase equilibrium apparatus was type that circulated the vapor and liquid phase, the expended volume measuring system was adopted to microsampling technique for the analysis. The phase equilibrium and mixture density data were obtained for carbon dioxide/${\alpha}$-tetralol system from liquid and vapor phase. The mole fraction of carbon dioxide in liquid phase decreases and the mole fraction of ${\alpha}$-tetralol in vapor phase increases at constant pressure according to increment of temperature, and both the densities of the vapor and liquid phase approach to the mixture critical density as the pressure increases at any temperature. For she thermodynamic analysis, the experimental data were correlated with Peng-Robinson equation in cubic equation of state and compared to theoretical values of carbon dioxide/${\alpha}$-tetralol system. The AAD result was in the range of 1.08%~8.93% in the case of K(1), and was in the range of 45.71%~72.34% in the case of K(2).

• Journal of Environmental Science International
• /
• v.15 no.5
• /
• pp.405-415
• /
• 2006

Sixteen soil samples around six areas (residental area, traffic area, power plant area, incineration area and factory area) where the stationary and mobile sources of polycyclic aromatic hydrocarbons (PAHs) are estimated to be emitted in Jeju City, were collected during Feburuary to March, 2004, and analyzed for 16 PAHs recommended by US EPA as primary pollutants to investigate their distribution characteristics. The concentrations of total PAHs (t-PAHs) and total carcinogenic PAHs $(t-PAH_{CARC})$ in soils of Jeju City were in the range of $21.7\sim264.2ng/g$ on a dry weight basis with a mean value of 87.2 ng/g and $6.3\sim118.0ng/g$ with a mean value of 33.4 ng/g, respectively. The concentrations of t-PAHs were low in comparison with those in soils of other domestic and foreign countries. The mean concentrations of t-PAHs and $(t-PAH_{CARC})$ with area decreased in the following sequences: traffic area> incineration area > factory area > power generation area > harbor area enli residental area. The correlation between t-PAHs and $(t-PAH_{CARC})$ were very high $(\gamma^2=0.9701)$, indicating that $(t-PAH_{CARC})$ concentration increases in proportion with t-PAHs. Comparing the distribution ratio of ring PAHs with area among 16 PAHs, it decreased in the order of 4-ring > 5-ring > 6-ring > 3-ring > 2-ring in all the areas except for harbor area. whitens for harbor area it was similar among 3-, 4- and 5-ring with high value. Low and no correlations between t-PAHs and soil compositions (organic matter content and particle size distribution) were observed, which is considered to be caused by the complex factors, such as the loading and characteristics of PAHs and diverse soil environment change, etc. From the examination of the three PAH origin indices, such as LMW/HMW (low molecular weight $2\sim3$ ring PAHs over high molecular weight $4\sim6$ ring PAHs), phenanthrene/anthracene ratio and fluoranthene/pyrene ratio, it can be concluded that the soil PAH contaminations were ascribed to strong pyrogenic origin in ail areas except for harbor area and to both pyrogenic and petrogenic origins.

• Journal of Preventive Medicine and Public Health
• /
• v.41 no.1
• /
• pp.61-67
• /
• 2008

Objectives : Polycyclic aromatic hydrocarbons (PAH) and toluene have been reported to induce reactive oxygen species and oxidative stress. This study was performed to investigate the effects of low level exposure to PAHs or toluene on the lipid peroxidation level in elementary school children and the elderly in a rural area. Methods : Forty seven elementary school children and 40 elderly people who were living in a rural area and not occupationally exposed to PAH or toluene were the subjects of this study. Information about active or passive smoking and diet was obtained using a self-administered questionnaire. The urinary 1-hydroxypyrene (1-OHP), 2-naphthol, hippuric acid and thiobarbituric acid reactive substance (TBARS) concentrations were measured, and these values were corrected with the urinary creatinine concentration. Results : In school children, the geometric means of the urinary 1-OHP, 2-naphthol, hippuric acid and TBARS levels were $0.02\;{\mu}mol/mol$ creatinine, $0.47\;{\mu}mol/mol$ creatinine, 0.14 g/g creatinine and $0.95\;{\mu}mol/g$ creatinine, respectively. Those values for the elderly were $0.07{\mu}mol/mol$ creatinine, $1.87{\mu}mol/mol$ creatinine, 0.11 g/g creatinine and $1.18\;{\mu}mol/g$ creatinine, respectively. The mean levels of urinary 1-OHP, 2-naphthol and TBARS were significantly higher in the elderly subjects than in the children. The urinary TBARS level was not correlated with the urinary 1-OHP, 2-naphthol and hippuric acid, but they were correlated with the age of the subjects. Conclusions : These results suggest that low level inhalation exposure to PAH or toluene does not markedly increase lipid peroxidation, and age is a significant determinant of lipid peroxidation.