Department of Civil and Environmental Engineering, Mines Douai, LGCGE-GCE, F-59508, Douai, France.
Lille University of Science and Technology, F-59650, Villeneuve d'Ascq, France.
Environ Sci Pollut Res Int. 2016 Feb;23(3):2426-36. doi: 10.1007/s11356-015-5462-y. Epub 2015 Sep 29.
Resuspension of bedded sediments was simulated under laboratory-controlled conditions in order to assess the amount of polycyclic aromatic hydrocarbons (PAH) remobilized in the dissolved fraction during one short and vigorous mixing. The desorbed amount of PAH was compared to the exchangeable fraction, the total amount of PAH sorbed on the sediment particles, and the dissolved PAH amount contained in the interstitial pore waters in order to evaluate the contribution of each fraction to the total amount of PAH released. To monitor the desorption of PAH and measure low trace level concentrations, passive samplers were used in an experimental open flow through exposure simulator. Results show that for the selected sediment, a substantial fraction of sorbed PAH (69 % of the total amount) is not available for remobilization in a depleted medium. Obtained data pinpoint that over 9 days, only 0.007 % of PAH are desorbed by passive diffusion through a water-sediment interface area of 415 cm(2) and that an intense resuspension event of 15 min induces desorption of 0.015 % of PAH during the following 9 days. Results also highlight that during resuspension simulation, modifications of the sediment and the water body occurred since partitioning constants of some pollutants between sediment and water have significantly decreased.
为了评估在一次短暂而剧烈的混合过程中，溶解部分中再悬浮床层沉积物所再移动的多环芳烃（PAH）的量，在实验室控制条件下模拟了床层沉积物的再悬浮。将解吸的 PAH 量与可交换部分、吸附在沉积物颗粒上的总 PAH 量以及包含在间隙孔隙水中的溶解 PAH 量进行了比较，以评估每个部分对总释放 PAH 量的贡献。为了监测 PAH 的解吸并测量痕量低浓度，在实验性开放流动通过暴露模拟器中使用了被动采样器。结果表明，对于所选沉积物，大量被吸附的 PAH（总数量的 69%）在贫化介质中不可用于再移动。获得的数据表明，在 9 天内，仅通过 415 cm²的水-沉积物界面的被动扩散就有 0.007%的 PAH 解吸，而 15 分钟的强烈再悬浮事件会在接下来的 9 天内诱导 0.015%的 PAH 解吸。结果还强调，在再悬浮模拟过程中，由于一些污染物在沉积物和水体之间的分配常数显著降低，沉积物和水体发生了变化。
