• Title/Summary/Keyword: PCBs homologs

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The Distribution Characteristics of Polychlorinated Biphenyls in Rural Atmosphere

  • Yeo, Hyun-Gu;Park, Minkyu;Chun, Man-Young;Young Sunwoo
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.E3
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    • pp.143-151
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    • 2002
  • Atmospheric concentrations of polychlorinated biphenyl (PCB) congeners were measured every two weeks from July, 1999 to January, 2000 at Hankyong University in Ansung, Kyounggi-do. Atmospheric concentrations of ∑$_{24}$PCB showed a range of 19.8~71.9 pg/m3. The highest concentration of PCB homolog was tri-CBs (sum of PCB 18, 27, 28, 33, 38) which had a comparatively higher vapor pressure than other homologs. The contribution ratio of lighter PCB homologs (tri-CBs) to total PCBs was 44.5%, and these homologs were the main components of PCBs. The ratio PCB homologs/deca-CB (PCB 209) suggested that the contribution of vapor phase PCBs increased greatly in summer relative to other seasons. In addition, the regression lines for PCB homologs/deca-CB (PCB 209) and temperature ($^{\circ}C$) appeared as an exponential function with high correlation (R2>0.67, p< 0.01). This suggests that the concentration of vapor phase PCB homologs increases steeply with increasing temperature.

Concentration and Seasonal Variation of Particle PCBs in Air

  • Yeo Hyun-Gu;Chun Man-Young
    • Journal of Korean Society for Atmospheric Environment
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    • v.21 no.E1
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    • pp.13-21
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    • 2005
  • Atmospheric concentrations of PCBs were monitored in Ansung-city, Kyonggi province during the 2001/2002 to characterize the concentration distribution and seasonal variation of particle polychlorinated biphenyls (PCBs). Average concentration of particle bound PCB showed maximum value for penta-CBs and minimum value for octa-CBs. Seasonal contributions $(%\)$ of total particle PCBs showed the highest value in winter months and lowest value in summer month, This result indicated that concentration of total particle PCBs increased with decreasing temperature in the atmosphere. Therefore, particle PCBs were easily formed by the condensation of gas phase PCBs in winter months. The total particle PCBs exhibited an inverse correlation with temperature (p<0.01) which suggested that particle PCBs were easily formed by condensation of gaseous PCBs in winter months.

Air-Soil Partitioning of PCBs in Rural Area

  • Yeo, Hyun-Gu;Park, Min-Kyu;Chun, Man-Young;Young, Sun-Woo
    • Journal of Korean Society for Atmospheric Environment
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    • v.19 no.E1
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    • pp.1-9
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    • 2003
  • The soil concentrations of polychlorinated biphenyls (PCBs) were measured at 12 sites in Ansung, Kyonggi province, Korea. Correlation coefficient (r) between total PCBs and organic matter content (OM) was significant (r=0.562, p< 0.05). It suggests that organic matter may be a key factor of soil absorption of PCBs. The PCB concentrations of low chlorinated congeners with high vapor pressure were relatively abundant in air but high chlorinated congeners with low vapor pressure were mainly dominated by soil. The results indicated the influence of physicochemical properties of PCBs such as vapor pressure, octanol - air partition coefficient ( $K_{OA}$ ). The calculated soil/air fugacity quotients suggested that the soil may be a source of heavier molecular PCBs (>penta-CBs) to the atmosphere, where lighter molecular PCBs appear to be affected by a movement from air to soil, especially tetra-CBs. Therefore, PCB homologs with low vapor pressure might have been influenced by revolatilization from soil.

Characteristic Factors of Air-Plant Partitioning of PCBs (PCBs의 대기-식물간 분배 특성 인자들)

  • 여현구;최민규;천만영;김태욱;선우영
    • Journal of Korean Society for Atmospheric Environment
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    • v.17 no.5
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    • pp.415-424
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    • 2001
  • The concentrations of PCBs (polychlorinated biphenyls) in air and plants (MOrus allba, Allum turberosum) were measured every other week at Hankyong University located in Ansung, Kyoung-ki province, Korea from July to November in 1999. Total concentrations of PCBs in air ranged from 19.8 to 71.9 pg/ $m^3$. It was observed in air that the concentrations of tai-chlorinated biphenyls(CBs) were higher than those of other PCB homologs probably due to their higher vapor pressure. Total concentrations of PCBs in plants ranged from 24.5 to 1,287 pg/g dry weight for Morus allba and 26.5 to 337 pg/g dry weight for Allum turberosum. A positive linear correlation was observed between log plant-air partition coefficients ( $m^3$air/g plant dry weight-defined here as the scavenging coefficient[S.C]) and log octanol-air partition coefficients ( $K_{oa}$ ) for each plant. In this study, slope of log S.C and log $K_{oa}$ for Morus allba, Allum turberosum were 1.07 ($R^2$= 0.83, p<0.01), 0.84 ($R^2$=0.53, p<0.05), respectively. This means that these plants may approach to equilibrium for air-plant partitioning.

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Accumulation Levels and Distribution Characteristics of Polychlorinated Biphenyls in Crucians and Leopard Frogs from the Nakdong River Basin (낙동강 유역에 서식하는 붕어와 황소개구리 체내의 Polychlorinated biphenyls의 축적도와 분포특성)

  • Moon, Ji Yong;Lee, Sung In;Song, Heeyoung;Lee, Kyoung Jin;Choi, Kyunghee;Jeong, Gi Ho
    • Analytical Science and Technology
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    • v.17 no.4
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    • pp.347-354
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    • 2004
  • We collected crucians (Carassius auratus) and leopard frogs(Rana pipiens) along the Nakdong River and the basin area at five locations from Koomi to Nakdong-estuary. The muscular tissue were separated and a GC-MSD system was used for quantification of PCBs. The 62 PCB congeners which represent total PCB levels were selected as analytes. We determined concentrations of PCBs and studied distribution characteristics by individual congeners and homologs. In the crucian, 24 congeners were detected and total PCB levels ranged from 0.74 to 5.41 ng/g wet weight. In the leopard frog, however, only 2 congeners were detected from Nakdong estuary only. The PCB level was 0.24 ng/g wet weight, around 22 times lower than the crucians. The PCB 153 showed the highest concentrations in the congeners and penta- and hexa-CBs showed the strong predominance which accounted for 78% of the total PCBs.

Temperature Dependence of PCBs in Urban Area of Seoul City (서울 대기 중 PCBs의 온도 의존성)

  • 여현구;최민규;천만영;김태욱;선우영
    • Journal of Korean Society for Atmospheric Environment
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    • v.18 no.3
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    • pp.193-204
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    • 2002
  • To investigate the relationships between the atmospheric concentrations of PCBs and temperature, quantity of both parameters was performed at an urban site in Korea from July 1999 to January 2000. The strength of correlations between total PCB and temperature was found to be significant (r = 0.752, p < 0.001). It hence indicates that total PCB contents were affected sensitively by temperature change during the sampling period. The ratio of PCB homologs and Deca-CB(PCB 209) also behaved quite similarly to the change of temperature (r>0.60, p<0.05). This may be inferable with the progress of the gas/particle partitioning to the gas phase, especially for fri-and tetra-CBs. Because they have high vapor pressure, they generally exist in the gas phase. The Clausius-Clapeyron equation was applied to the atmospheric PCB data, relating PCB partial vapor pressure to inverse temperature. This may essentially represent the temperature-controlled transition between condensed phase and atmospheric gas phase. The slopes of the resulting plot with International Council for the Explanation of the Seas (ICES) congener ranged from -2810 to -5887, with significantly steep slope and $R^2$(p< 0.005) It was inferred that the PCB atmospheric concentration was also affected by change in the surrounding conditions such as soil, lakes and trees.

Deposition Characteristics of Atmospheric PCBs Depending on Exposure Periods Using Pine Needles (소나무 잎을 이용한 대기 중 PCBs의 노출기간별 침착특성)

  • Yeo, Hyun-Gu;Cho, Ki-Chul;Choi, Min-Kyu;Kim, Tae-Wook;Chun, Man-Young
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.8
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    • pp.836-842
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    • 2006
  • Pine needle samples(1 year, 2 year, 3 year old) were collected in Seoul and Ansung to investigate the deposition characteristics of atmospheric PCBs depending on exposure periods. Total PCBs concentration of pine needle samples in Seoul and Ansung showed 2,429, 1,198 pg/g DW(dry weight), respectively. PCB homologs concentration of pine needle samples decreased with increasing chlorine-substituted compounds. It showed that higher chlorine- substituted compounds in existing particle phase compared to lower chlorine-substituted compounds existing in gaseous phase were difficult to accumulate lipids of the pine needles samples. The results of regression analysis between exposure periods in the atmosphere and concentration of total PCBs measured in pine needles at two sites showed significant levels($R^2>0.94$, p<0.01), which implies that atmospheric PCBs accumulated on pine needles with positive linearity depending on exposure periods in this study. Therefore pine needle samples can be used as passive air sampler(PAS) for monitoring air contamination for a long time in different sites.

Annual Cycle of PCBs Concentration in the Atmosphere

  • Kang, Byung-Wook;Shin, Eun-Sang;Yeo, Hyun-Gu
    • Journal of environmental and Sanitary engineering
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    • v.22 no.2
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    • pp.61-73
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    • 2007
  • PCBs의 대기 중 농도는 고용량 PUF sampler를 이용하여 2000년부터 2002년까지 주 1회 수도권 인근지역인 경기도 안성에서 측정하였다. 본 논문은 비선형 회귀모델을 이용하여 대기 중 가스상 PCBs의 연간, 월간 사이클을 평가 하고자 한다. Clausius-Clepeyron 식을 이용한 가스상 PCBs의 기울기는 고분자로 갈수록 증가하는 경향이었다. 이는 고분자 PCBs는 저분자 PCBs에 비해 온도 의존성이 크다는 것을 의미한다. 다시 말해, 고분자 PCBs는 다른 지역에서 장거리 이송되어 오는 오염물질의 영향 보다는 지역적인 오염원(예, 토양, 수계 등)에 의해 영향을 크게 받고 있다는 것을 시사한다. Lorentzian 모델을 이용한 총 PCBs의 일별, 월별 회귀식의 결정계수($R^2$)는 각각 0.62(p<0.0001), 0.88(p<0.0001)로 나타나 유의한 결과를 보였다. 또한, 비선형 회귀식 모델을 활용하여 구한 가스상 PCBs의 일별, 월별 싸이클을 모사한 방정식도 매우 유의한 결과(p<0.0001)를 나타내었다.

Composition, Source, and Regional Concentration of PBDEs in Pine Needles (소나무 잎 중 PBDEs의 조성, 발생원 및 지역적 농도)

  • Yeo, Hyun-Gu;Cho, Ki-Chul;Chun, Man-Young
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.8
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    • pp.829-835
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    • 2006
  • The composition, source, and regional concentration of polybrominated diphenyl ethers(PBDEs) were measured in pine needles with several sites in Korea. Homologs specific analysis confirmed that hepta-BDE(bromodiphenyl ethers) through deca-BDE were predictive indicator for total PBDEs concentration(Pearson's correlation coefficient r>0.96, p<0.001). Deca-BDE were detected in relatively very high concentration compared to other PBDE congeners in all samples. The similarity of between congeners profile to those of Bromkal 70-5DE and DE-71, the commercial mixture of PBDEs, indicates these mixtures are source of PBDEs observed in these sites. Also, BDE-47, -99, -100, -206, -207, and -209 were the dominant congeners in all samples, suggesting that the widely used commercial penta- and deca-BDE technical mixture were the original sources. However, Pearson's correlation coefficients of between BDE-209 and BDE-47, -99, -100 were insignificant, which implied that tetra-BDE and penta-BDE may originate from secondary sources such as air-plant partition in manner similar to that of the PCBs, while deca-BDE formulation still has primary sources.