• Title/Summary/Keyword: Gaseous PCBs concentration

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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.

Measurement of Atmospheric Dry Deposition and Size Distribution of Particulate PCBs in 1999 at Seoul

  • Park, Seong-Suk;Shin, Hye-Joung;Yi, Seung-Muk;Kim, Yong-Pyo
    • Journal of Korean Society for Atmospheric Environment
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    • v.22 no.E1
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    • pp.35-43
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    • 2006
  • Ambient particle size distributions of PCBs and their dry deposition fluxes were measured at a site in Seoul to quantify dry deposition fluxes of PCBs and size characteristics of PCBs in the air, and to estimate ambient concentrations of gaseous PCBs and dry deposition fluxes. The dry deposition plate was used to measure dry deposition fluxes of particulate mass and PCBs and a cascade impactor and rotary impactor were used to measure ambient particle size distributions for small ($D_p<9{\mu}m$) and large ($D_p>9{\mu}m$) particles, respectively. Six sample sets were collected from April to July 1999. The fluxes of particulate total PCBs (the sum of 43 congeners) ranged from 160 to $607ng\;m^{-2}day^{-1}$. The size distribution of total PCBs was bimodal with two peaks in small particle size ($D_p{\sim}0.6\;and\;6{\mu}m$, respectively) and, thus, mass concentration being dominant in small particles. The mean particulate PCBs concentration was $6.9{\mu}g$ PCBs/g. The concentrations of PCB homologues in the gas phase were estimated based on the particle/gas partition coefficient ($K_p$) with the measured values of particulate PCBs in this study and they were comparable to those observed in other previous studies. Dry deposition fluxes were estimated by calculating dry deposition velocities.

Gas-Particle Partitioning of PCBs in Ambient Air, Yokohama Japan (일본 요코하마 대기 중 PCBs의 가스-입자 분배)

  • Kim Kyoung-Soo
    • Journal of Korean Society for Atmospheric Environment
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    • v.21 no.3
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    • pp.285-293
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    • 2005
  • This study was aimed at estimation of gas-particle partitioning of polychlorinated biphenyls (PCBs) in ambient air. The samples were collected at urban site in Japan from March 2002 to January 2003. The concentration of total PCBs (from 4 CB to 10 CB) and TEQ (Toxic equivalent) ranged from 62 to $247\;pg/m^3$ and from 2 to $14\;fgTEQ/m^3 $, respectively. The average contribution $(\%)$ of gas phase to total PCBs concentration was above $80\%$, which suggests that in the atmosphere PCBs predominantly existed in the gas phase. The weak correlations between total PCBs concentration and temperature was found. However this result was due to a typhoon during summer and raining during sampling period. The gas-particle partition coefficient (Kp) was obtained as a function of temperature. The partition ratio of gaseous and particulate phase PCBs can be estimated for an arbitrary temperature. The plot of gas/particle partition coefficient (log Kp) vs. sub-cooled liquid vapor pressure $(log\;P_L)$ had reasonable correlations for individual samples but the slope varied among the samples (coefficients of determination for log Kp versus log $P_L$ plot were> 0.76 $(p<0.0001)$, except for 3 samples). As a result, the variations in the slope among the sampling period may be due to change of temperature, raining during sampling period and wind in this study.

Concentration Characteristics of PCBs in Pine Needle and Soil at Rural Area (교외지역에서 소나무 잎과 토양 중 PCBs의 농도 특성)

  • Shin Eun-Sang;Yeo Hyun-Gu
    • Journal of environmental and Sanitary engineering
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    • v.21 no.1 s.59
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    • pp.1-11
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    • 2006
  • This study was to investigate concentration characteristics of atmospheric PCBs in soil sample and pine needle at rural area. Profiles of PCB congener detected in pine needle and soil sample have a difference that low molecular PCBs mainly existed in pine needle, whereas high molecular PCBs were mainly existed in soil sample because of their different vapor pressure and octanol-air partitioning coefficient($K_{OA}$) of each congeners. Correlation coefficients(r) of PCB congeners simultaneously detected in soil and pine needle were significant (r>0.71, p<0.01), which showed that PCB congeners patterns of atmosphere could be estimated in using pine needle and soil sample indirectly. The contributions(%) of higher molecular PCBs(>penta-CB) to total PCBs in soil sample were higher than those of pine needle and the contribution of lower molecular PCBs(

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.