• Title/Summary/Keyword: $logK_{oa}-log(C_p/C_a)$

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Estimation of PCDD/Fs Concentrations in Ambient Air Using Pine Needles as a Passive Air Sampler (PAS) (소나무 잎을 PAS로 이용하여 대기 중 PCDD/Fs 농도 추정)

  • Chun, Man-Young
    • Journal of Environmental Health Sciences
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    • v.41 no.2
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    • pp.116-125
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    • 2015
  • Objective: This study was carried out to use pine needles as a passive air sampler (PAS) for atmospheric polychlorinared dibenzo-p-dioxins/furans (PCDD/Fs). Methods: PCDD/Fs concentrations in ambient air ($C_a$, $pg/m^3$) and deposited pine needles ($C_p$, pg/g dry) were analyzed simultaneously from June 1 to December 31. Air samples were taken using two low volume PUF active air samplers with an overall average air volume of approximately $1,200Sm^3$. Pine needles were collected the end of December near the air sampler. PCDD/Fs was analyzed by HRGC/HRMs. Results: A good correlation was shown ($R^2=0.6357$, p=0.0001) between $C_a$ and $C_p$, but a better correlation ($R^2=0.7372$, p<0.0001) existed between the logarithm of octanol-air partitioning coefficient ($LogK_{oa}$) and Log($C_p/C_a$). The average PCDD/Fs sampling rates from air to pine needles were 0.045($0.018-0.185m^3/day-g\;dry$). Conclusion: It was found that pine needles can be used as PAS for atmospheric PCDD/Fs, and they are especially suitable for long time PAS compared to PUF disk PAS.

Estimation of Atmospheric PCBs Concentrations of Several Sites Using Pine Needles as Passive Air Sampler(PAS) (소나무잎을 PAS로 이용하여 지역별 대기 중 PCBs 농도 추정)

  • Chun, Man-Young
    • Journal of Environmental Health Sciences
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    • v.39 no.2
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    • pp.159-165
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    • 2013
  • Objective: This study was carried out in order to estimate atmospheric Polychlorinated Biphenyls (PCBs) concentrations using pine needles as a passive air sampler (PAS) in urban, semi-rural and rural regions. Methods: One-year old pine needles were collected to analyze their PCBs concentrations ($C_p$, pg/g dry) at the end of December. PCBs concentrations in ambient air ($C_a$, $pg/m^3$) were calculated with the $logK_{oa}-log(C_p/C_a)$) model. Results: PCBs concentrations in ambient air ($C_a$) were high in the order of urban, semi-rural and rural regions. The lower-chlorinated PCBs showed a higher concentration in ambient air. However, the distribution of PCBs congeners was similar in all three regions. Correlation between $C_a$ and the population density of the three regions was significant ($R^2$=0.9834, p<0.001). Conclusions: It was concluded that although the production and use of PCBs was banned in the1970s, PCBs are currently being produced unintentionally by human activities.

Estimation of Atmospheric PAH Concentrations and Sources at Several Sites Using Pine Needles as a Passive Air Sampler (소나무잎을 Passive Air Sampler로 이용하여 지역별 대기 중 다환방향족 탄화수소의 농도 및 발생원 추정)

  • Chun, Man-Young
    • Journal of Environmental Health Sciences
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    • v.40 no.1
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    • pp.38-46
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    • 2014
  • Objectives: This study was carried out in order to estimate atmospheric polycyclic aromatic hydrocarbon (PAH) concentrations and sources using pine needles as a passive air sampler (PAS) in urban (Pyeongtaek), semirural (Anseong) and rural (Jincheon) sites. Methods: One-year-old pine needles were collected for analysis of their PAH concentrations ($C_{p,n}g/g$ dry) at the end of December. PAHs concentrations in the ambient air ($C_a$, $ng/m^3$) were calculated with a $Log(C_p/C_a)-LogK_{oa}$ correlational equation. Results: PAHs concentrations in ambient air ($C_a$) were high, in the order of urban ($114.03ng/m^3$), semirural ($105.17ng/m^3$) and rural ($61.91ng/m^3$) sites. However, distributions of PAH isomer concentrations were very similar. PAHs of which molecular weight is smaller than 228.30 (AcPy, Acp, Flu, Phen, Ant, Flt, Pyr, BaA, Chry) made up most of the PAHs in the ambient air (96.6-98.5%). Conclusion: At urban, semirural and rural sites, it was concluded that the main source of PAHs in the ambient air ratio of each PAH isomer concentration was cars, especially diesel vehicles.

Estimation of PCBs Concentrations in Ambient Air Using Pine Needles as a Passive Air Sampler (PAS) (소나무잎을 Passive Air Sampler(PAS)로 이용하여 대기 중 PCBs 농도 추정)

  • Chun, Man-Young
    • Journal of Environmental Health Sciences
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    • v.38 no.4
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    • pp.360-368
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    • 2012
  • Objective: This study was carried out to use pine needles as a passive air sampler (PAS) of atmospheric Polychlorinated Biphenyls (PCBs). Methods: PCB concentrations in ambient air ($C_a$, ng/$m^3$) and deposited on pine needles ($C_p$, ng/g dry) were analyzed simultaneously from June 1 to December 31. Air samples were taken using a low volume PUF active air sampler and the overall average air volume was about 900-1,000 $m^3$. Pine needles were collected at the end of August and December near the air sampler. Results: $C_a$ were higher at higher air temperature and lower chlorinated PCB congeners, but $C_p$ showed irregular distribution. The average PCB sampling rates from air to pine needles were 0.116 (0.002-0.389) $m^3$/day - g dry. Conclusions: A poor correlation was shown between $C_a$ and $C_p$. However, a good correlation was shown between the logarithm of octanol-air partitioning coefficient ($logK_{oa}$) and log ($C_p/C_a$), and the interrelation was better with longer sampling time (June to December) than shorter sampling time (June to August). The average PCB sampling rates from air to pine needles were the lowest with respect to PUF disk, XAD-2 resin and semipermeable membrane devices (SPMDs) PAS. The average ratio ($C_{a-calc}/C_{a-meas}$) of calculated ($C_{a-calc}$) and measured ($C_{a-meas}$) PCB concentration was 0.69 with a shorter sampling time and 1.24 with a longer, so $C_{a-calc}$ was close to $C_{a-meas}$. It was found that pine needles can be used as PAS of atmospheric PCBs, and are especially suitable for long-time PAS.

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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Concentration and Gas-particle Partition of PCDDs/Fs and dl-PCBs in the Ambient Air of Ansan Area (안산지역 대기 중 다이옥신 및 dl-PCBs의 오염특성 조사)

  • Heo, Jong-Won;Kim, Dong-Gi;Song, Il-Seok;Lee, Gang-Woong
    • Journal of Korean Society for Atmospheric Environment
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    • v.26 no.5
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    • pp.517-532
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    • 2010
  • After establishment of Banwol industrial complex in 1987, Ansan city becomes the largest industrial sector development in Gyeonggi-do, Korea. As the population and industrial activity grow over this region, toxic air pollutants, particularly POPs (Persistent Organic Pollutants) from various emission sources have been major public concerns. Air samples for POPs monitoring were collected at the industrial sites ($A_2$), residential sites ($B_1$, $B_2$), commercial site (C), and rural/remote site (D) of the area of Ansan during 2008 with a prolonged industrial sampling site $A_1$ from 2001 to 2008. All samples were analysed for 2,3,7,8 substituted-polychlorinated dibenzo-p-dioxin and dibenzofurans (PCDD/Fs) and dioxin like polychlorinatd diphenyls (dl-PCBs). In site $A_1$, a steady decline of their concentrations from 2003 to 2008 was observed due to the reinforced emission guideline from waste incinerators. The average concentration of the PCDD/Fs and dl-PCBs ranged between 0.118 pg-TEQ/$m^3$ (rural/remote site D) and 0.532 pg-TEQ/$m^3$ (industrial area $A_2$). These level were generally consistent with previous studies in Gyeonggi-do, while higher than other places. Most of PCDD/Fs congener were partitioned into particle phase, whereas dl-PCBs were partitioned into gas phase. The logarithm of gas-particle partition coefficient $K_P$ of dl-PCBs and PCDD/Fs were well correlated with sub-cooled liquid vapor pressure $P_L$. The slope $m_T$ of log $K_P$ versus log $P_L$ for PCDD/Fs (-1.22) and dl-PCBs (-1.02) in industrial area ($A_2$) were high compared to other residential/commercial area. It suggests that this area was likely influenced by the direct emission source of PCDD/Fs and dl-PCBs. To simulate the partition of PCDD/Fs and dl-PCBs between gas and particle phase, Junge-Pankow model ($P_L$-base) and $K_{oa}$ model were applied. It was found that J-P model was more suitable than the $K_{oa}$ model in this study.