Air-Seawater Gas Exchange and Dry Deposition of Chlorinated Paraffins in a Typical Inner Sea (Liaodong Bay), North China
Air-Seawater Gas Exchange and Dry Deposition of Chlorinated Paraffins in a Typical Inner Sea (Liaodong Bay), North China
复制标题
华北典型内海（辽东湾）海气气体交换及氯化石蜡干沉积
DOI：
10.1021/acs.est.8b01803
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发表时间：
2018-07-17
影响因子：
11.4
通讯作者：
Jiang, Guibin
中科院分区：
文献类型：
--
作者：
Ma, Xindong;Wang, Yawei;Jiang, Guibin
短链氯化石蜡（SCCPs）和中链氯化石蜡（MCCPs）作为一类新的持久性有机污染物，近年来引起了世界各国的广泛关注。然而，关于环境行为的数据，特别是在大气传输和空气-海水交换，仍然是稀疏的。本研究采集了渤海海域四季的海洋边界层大气和海水样品，建立了一个逸度模型来估算CPs的大气-海水扩散和沉积通量。总体而言，夏季大气和海水样品中的总CP含量高于春季，空气中的CP主要以气相存在，海水中的CP主要以溶解态存在。就短链氯化石蜡而言，C-10和C-11组分是最丰富的同系物。对于中链氯化石蜡，C-14同系物主要存在于大气颗粒相和海水颗粒相。高氯同系物的对数逸度比（logf（a）/f（w））（Cl-8 ~ Cl-10：5月为0.71 ~ 1.32，8月为1.38 ~ 2.29）表明净沉降是主要的过程，而低氯同系物，尤其是Cl-5同系物在8月表现出净挥发的趋势（logf（a）/f（w）< -0.5）。扩散通量和干沉降通量的结果表明，在采样区，氯化石蜡的气-海气体交换显著高于干沉降。
As a group of new persistent organic pollutants, short-chain chlorinated paraffins (SCCPs) and medium-chain CP (MCCPs) have attracted extensive worldwide interest in recent years. However, the data regarding to the environmental behavior, especially in atmospheric transfer and air-seawater exchange, are still sparse. In this study, seasonal marine boundary layer air and seawater samples were collected from Chinese Bohai sea and a fugacity model was built to evaluate the air-seawater diffusion and deposition flux of CPs. Generally, the total CP levels in atmosphere and seawater samples in summer were higher than those in spring, and CPs existed mostly in the gaseous phase in air and the dissolved phase in seawater. For SCCPs, C-10 and C-11 components were the most abundant homologue groups. For MCCPs, the C-14 homologue dominated in the particle phase of atmosphere and particulate phase of seawater. The logarithmic fugacity ratios (log f(a)/f(w)) of higher chlorinated congeners (Cl-8 to Cl-10: 0.71 to 1.32 in May and 1.38 to 2.29 in August) indicated that net deposition was the predominant process, whereas lower chlorinated congeners, especially Cl-5 homologue groups in August, showed a trend of net volitization (log f(a)/f(w) < -0.5). The results of diffusion and dry deposition fluxes indicated that air-seawater gas exchange of CPs was significantly higher than dry deposition in the sampling areas.