Civil & Environmental Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ, USA.
Chemistry, Rutgers, The State University of New Jersey, Camden, NJ, USA.
Chemosphere. 2021 Jun;272:129886. doi: 10.1016/j.chemosphere.2021.129886. Epub 2021 Feb 8.
Comprehensive approaches are needed to understand accumulation patterns and the relative importance of pathways of entry for microplastics in the marine environment. Here, a highly urbanized estuarine environment was sampled along a salinity gradient from the mouth of the Raritan River, (New Jersey, USA) and into the Raritan Bay and the coastal ocean which are further influenced by discharge from the larger Hudson River. Polymers were characterized in two size classes by FTIR and/or Raman spectroscopy. The highest concentration of 500-2000 μm microplastic particles were observed in the mouth of the Raritan during summer low flow conditions, whereas the 250-500 μm microplastic particles were more prevalent in the bay and coastal ocean samples. These results were interpreted using fragmentation and mixing models to provide insight into the sources and fate of microplastics in this estuarine/coastal region. To investigate the potential pathways of entry into the system, samples were collected from various hydraulically connected storm water outfalls and the influent and effluent of wastewater treatment plants and polymer concentrations and types were compared to the estuarine samples. The concentrations of microplastics (500-2000 μm) ranged from 400 to 600 microplastics/m in storm water compared to <1-2.75 microplastics/m across the estuary. Of interest for analysis is the observed linear correlation between the total concentration of particles in a sample following oxidation and density separation and its microplastic concentration. Overall, the results presented reveal potentially important sources of microplastics in the estuarine environment and have implications for understanding the behavior, transport, and fate of microplastics under varying flow conditions and from estuaries with variable flushing times.
需要综合的方法来理解微塑料在海洋环境中的积累模式和进入途径的相对重要性。在这里，一个高度城市化的河口环境沿着盐度梯度从拉特里河（美国新泽西州）的河口采样，并进入拉特里湾和沿海海洋，这些地区进一步受到更大的哈德逊河排放的影响。聚合物通过傅里叶变换红外光谱（FTIR）和/或拉曼光谱在两个尺寸类别中进行了特征描述。在夏季低流量条件下，拉特里河口处观察到 500-2000μm 微塑料颗粒的最高浓度，而 250-500μm 微塑料颗粒在湾和沿海海洋样本中更为普遍。这些结果通过破碎和混合模型进行了解释，以提供对该河口/沿海地区微塑料来源和命运的深入了解。为了研究潜在的进入途径，从各种水力连接的雨水排放口以及废水处理厂的进水和出水收集了样品，并将聚合物浓度和类型与河口样品进行了比较。微塑料（500-2000μm）的浓度在雨水从 400 到 600 微塑料/m 不等，而在整个河口的浓度范围从<1 到 2.75 微塑料/m。值得分析的是，观察到样品中经氧化和密度分离后的颗粒总浓度与其微塑料浓度之间存在线性相关性。总的来说，所呈现的结果揭示了河口环境中微塑料的潜在重要来源，对于理解在不同流动条件下以及在具有不同冲洗时间的河口的微塑料的行为、传输和命运具有重要意义。
