CNRS/Univ Pau & Pays Adour/ E2S UPPA, Institut des sciences analytiques et de physicochimie pour l'environnement et les matériaux, UMR 5254, 64000, Pau, France.
Géosciences Rennes, UMR 6118, CNRS - Université de Rennes 1, Av. Général Leclerc, Campus de Beaulieu, 35000 Rennes, France.
Environ Pollut. 2021 Jan 1;268(Pt B):115170. doi: 10.1016/j.envpol.2020.115170. Epub 2020 Jul 11.
Fate, transport and accumulation of nanoplastics have attracted considerable attention in the past few years. While actual researches have been focused on nanoplastics dispersed or aggregated in different environmental system, no study have been focused on the possibility that nanoplastics are co-transported with other natural or anthropogenic materials. Therefore, the large quantity of debris released in the environment, such as cigarette butts (CGB), could be part of the nanoplastics fate and behavior. Here we show the considerable sorption capacities of cigarette filters for nanoplastics. To address this topic, we chose polystyrene-based nanoplastics with similar state of charge (according to the physico-chemical characteristic of the zeta potential -45 to -40 mV) but with different sizes (50-800 nm) and morphologies. A kinetic approach to sorption in fresh water (pH = 8.05; 179.5 μS cm) at room temperature was carried out by means of the flow field flow analysis method (AF4) to determine the partition coefficients and water sampling rates between nanoplastics and cigarette butts. Using different models of, more or less environmentally relevant, nanoplastics (NPTs) and adequate analytical strategies, we found partition coefficients between the NPTs and CGBs ranged from 10 to 10 in freshwater conditions. We demonstrated that the physical features of the NPTs (size and morphology) have an influence on the sorption behaviour. Asymmetrical shaped NPTs with broader size distribution seems to be mostly retained in the CGBs after longer equilibration time. This result shows the importance of the NPTs features on the mechanisms governing their transfer and fate in the environment through environmental matrices, especially when other materials are involved. We anticipate our work to be a starting point for investigating the co-transport of NPTs with other materials present in the environment (natural and anthropogenic).
纳米塑料的命运、传输和积累在过去几年引起了相当大的关注。虽然实际研究集中在分散或聚集在不同环境系统中的纳米塑料，但没有研究集中在纳米塑料与其他天然或人为材料共同传输的可能性上。因此，环境中释放的大量碎片，如香烟过滤嘴（CGB），可能是纳米塑料命运和行为的一部分。在这里，我们展示了香烟过滤嘴对纳米塑料具有相当大的吸附能力。为了解决这个问题，我们选择了具有相似荷电状态（根据 zeta 电位的物理化学特性 -45 到 -40 mV）但大小（50-800nm）和形态不同的基于聚苯乙烯的纳米塑料。通过流动场流动分析方法（AF4）在室温下进行新鲜水中的吸附动力学研究（pH=8.05；179.5μS cm），以确定纳米塑料和香烟过滤嘴之间的分配系数和水采样率。使用不同的、或多或少与环境相关的纳米塑料（NPTs）模型和适当的分析策略，我们发现 NPTs 和 CGBs 之间的分配系数在淡水中范围从 10 到 10。我们证明了 NPTs 的物理特性（大小和形态）对吸附行为有影响。具有更宽分布的非对称形状的 NPTs 在更长的平衡时间后似乎主要保留在 CGBs 中。这一结果表明，NPTs 特征在控制其通过环境基质转移和命运的机制中非常重要，尤其是当涉及其他材料时。我们期望我们的工作为研究 NPTs 与环境中其他材料（天然和人为）的共同传输提供一个起点。
