Mi Lijie, Xie Zhiyong, Zhang Lulu, Waniek Joanna J, Pohlmann Thomas, Mi Wenying, Xu Weihai
Institute of Coastal Environmental Chemistry, Helmholtz-Zentrum Hereon, Geesthacht 21502, Germany.
Institute of Oceanography, University of Hamburg, Hamburg 20146, Germany.
Environ Health (Wash). 2023 Jul 16;1(3):191-202. doi: 10.1021/envhealth.3c00059. eCollection 2023 Sep 15.
Organophosphate esters (OPEs) have become one group of chemicals with emerging concern in the marine environment. In this work, we investigated OPEs in the air and seawater of the South China Sea in summer 2019. The concentrations of ∑OPEs in the atmosphere ranged from 66 to 550 pg/m, with TCIPP, TNBP, TPhP, and TEP predominating in the air. The total dissolved OPE concentrations (∑OPEs without TEP) measured in high-volume water samples ranged from 300 to 3600 pg/L, with a mean concentration of 1180 ± 910 pg/L. TEP was measured with liquid-liquid extraction (LLE), and it showed the highest concentration (average 2000 ± 1450 pg/L) among the selected OPEs. Total suspended matter associated OPEs accounted for less than 4.7% of the sum of OPE concentrations in seawater. Fugacity fractions and air-sea exchange fluxes showed that TCEP, TCIPP, TIBP, TEHP, TPhP, and EHDPP were favored to volatilize, TEP dominated the deposition, while TPrP and TNBP varied between volatilization and deposition. Atmospheric particle deposition fluxes ranged from 5 to 71 ng/m/day with an average of 17 ± 15 ng/m/day. The input of ∑OPEs to the entire South China Sea via atmospheric particle deposition was estimated to be 22 ± 19 tons/year, while the net air-sea exchange fluxes of OPEs were volatilization from seawater to air with an average of 44 ± 33 tons/year. This work suggests that air-sea exchange and atmospheric particle deposition are significant processes interfering with the transport of OPEs in the marine environment.
有机磷酸酯（OPEs）已成为海洋环境中一类新出现的受关注化学品。在本研究中，我们调查了2019年夏季中国南海空气和海水中的OPEs。大气中∑OPEs的浓度范围为66至550 pg/m³，其中三（2-氯异丙基）磷酸酯（TCIPP）、三正丁基磷酸酯（TNBP）、三苯基磷酸酯（TPhP）和三（2-乙基己基）磷酸酯（TEP）在大气中占主导地位。在大容量水样中测得的总溶解OPE浓度（不包括TEP的∑OPEs）范围为300至3600 pg/L，平均浓度为1180±910 pg/L。采用液液萃取（LLE）法测定TEP，在所选择的OPEs中它的浓度最高（平均2000±1450 pg/L）。与总悬浮颗粒物相关的OPEs占海水中OPE浓度总和的比例不到4.7%。逸度分数和气-海交换通量表明，三（2-氯乙基）磷酸酯（TCEP）、TCIPP、三异丁基磷酸酯（TIBP）、三（2-乙基己基）磷酸酯（TEHP）、TPhP和2-乙基己基二苯基磷酸酯（EHDPP）倾向于挥发，TEP以沉降为主，而三丙基磷酸酯（TPrP）和TNBP在挥发和沉降之间变化。大气颗粒物沉降通量范围为5至71 ng/m²/天，平均为17±15 ng/m²/天。据估计，通过大气颗粒物沉降输入到整个中国南海的∑OPEs为22±19吨/年，而OPEs的净气-海交换通量是从海水向大气挥发平均为44±33吨/年。这项研究表明，气-海交换和大气颗粒物沉降是影响海洋环境中OPEs迁移的重要过程。
