Jeon Junho, Kannan Kurunthachalam, Lim Byung J, An Kwang Guk, Kim Sang Don
Department of Environmental Science and Engineering, Gwangju Institute of Science and Technology, 1 Oryong-dong, Buk-gu, Gwangju 500-712, Korea.
J Environ Monit. 2011 Jun;13(6):1803-10. doi: 10.1039/c0em00791a. Epub 2011 Apr 15.
The influence of salinity and organic matter on the distribution coefficient (K(d)) for perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) in a brackish water-clay system was studied. The distribution coefficients (K(d)) for PFAs onto inorganic clay surfaces increased with salinity, providing evidence for electrostatic interaction for the sorption of PFAs, whereas the relationship between K(d) and organic carbon content (f(oc)) suggested that hydrophobic interaction is the primary driving force for the sorption of PFAs onto organic matter. The organic carbon normalized adsorption coefficient (K(oc)) of PFAs can be slightly overestimated due to the electrostatic interaction within uncoated inorganic surfaces. In addition, the dissolved organic matter released from coated clay particles seemed to solvate PFA molecules in solution, which contributed to a decrease in K(d). A positive relationship between K(d) and salinity was apparent, but an empirical relationship for the 'salting-out' effect was not evident. The K(d) values of PFAs are relatively small compared with those reported for persistent organic pollutants. Thus, sorption may not be a significant route of mass transfer of PFAs from water columns in estuarine environments. However, enhancement of sorption of PFAs to particulate matter at high salinity values could evoke potential risks to benthic organisms in estuarine areas.
研究了盐度和有机物对微咸水 - 黏土体系中全氟辛烷磺酸（PFOS）和全氟辛酸（PFOA）分配系数（K(d)）的影响。全氟烷基酸在无机黏土表面的分配系数（K(d)）随盐度增加而增大，这为全氟烷基酸吸附的静电相互作用提供了证据，而K(d)与有机碳含量（f(oc)）之间的关系表明，疏水相互作用是全氟烷基酸吸附到有机物上的主要驱动力。由于未包覆的无机表面内的静电相互作用，全氟烷基酸的有机碳归一化吸附系数（K(oc)）可能会被略微高估。此外，从包覆黏土颗粒释放的溶解有机物似乎会使溶液中的全氟烷基酸分子溶剂化，这导致K(d)降低。K(d)与盐度之间存在明显的正相关关系，但“盐析”效应的经验关系并不明显。与持久性有机污染物报道的K(d)值相比，全氟烷基酸的K(d)值相对较小。因此，吸附可能不是河口环境水柱中全氟烷基酸质量转移的重要途径。然而，在高盐度值下全氟烷基酸对颗粒物吸附的增强可能会给河口地区的底栖生物带来潜在风险。
