title: Measurement of partition coefficients for selected polycyclic aromatic hydrocarbons between isolated plant cuticles and water.
abstract: Partition coefficients between plant cuticles and water (Kcutw) were measured for 10 selected polycyclic aromatic hydrocarbons (PAHs) to evaluate the sorption capacity of plant cuticular layers for hydrophobic organic chemicals. The partitioning properties of PAHs between cuticles and water were evaluated by using (1) isolated cuticular layers and (2) leaf homogenate. The abaxial and adaxial cuticular layers of Euonymus japonicus were isolated by enzymatic digestion. A third-phase partitioning method using poly(dimethylsiloxane) (PDMS) was used to obtain Kcutw. The Kcutw values for the selected PAHs showed no significant differences between the abaxial and adaxial cuticular layers and ranged between 10(4.1) and 10(7.6). These values are close to or slightly higher than their 1-octanol/water partition coefficient (log Kow), indicating high sorption capacity of plant cuticles. On the contrary, partition coefficients between the lipid tissues of homogenized leaves and water were lower than those obtained using isolated cuticular layers by factors of 3.7-190, which is likely due to the breakdown of lipid layers. This indicates that the sorption of hydrophobic organic chemicals by plant leaves is better evaluated using isolated cuticles and that the sorption potential of plant leaves may be underestimated when leaf homogenates are used.
authors.affiliation: Environmental Research Institute, Ajou University, 206 Worldcup-ro, Yeongtong-gu, Suwon 443-749, Republic of Korea.
authors.forename: Su-Jin
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Division of Environmental Science and Ecological Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 136-713, Republic of Korea.
authors.forename: Hwang
authors.initials: H
authors.lastname: Lee
authors.affiliation: Division of Environmental Science and Ecological Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul 136-713, Republic of Korea. Electronic address: junghwankwon@korea.ac.kr.
authors.forename: Jung-Hwan
authors.initials: JH
authors.lastname: Kwon
mesh_terms: D004784:Environmental Monitoring; D005618:Fresh Water / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D010944:Plants / Q000378:metabolism*; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism*
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical
keywords: Environmental fate; Hydrophobic organic chemicals; Partition coefficient; Plant; Polycyclic aromatic hydrocarbons (PAHs); Quantitative structure–activity relationship (QSAR)