Microplastics are a ubiquitous environmental contaminant whose distributions have been correlated with land-use and population density. Although there are numerous studies quantifying microplastics in the environment, local studies help inform sources, pathways, and policy. Here, we measure the concentration of microplastics in the surface waters across the Chesapeake Bay – the largest estuary in the USA. Thirty surface water samples from throughout the Chesapeake Bay were collected with a manta trawl. Samples were manually processed for microplastics and other anthropogenic particles. Fourier-transform infrared spectroscopy (FTIR) was used to determine the chemical composition of the particles. Higher concentrations were found near major cities and where larger rivers or tributaries met the Chesapeake Bay. Fragments, films, and fibres were the most common morphologies found, and polyethylene and polypropylene were the most common plastic types. These results can be used to inform mitigation strategies for microplastic pollution in the Chesapeake Bay region.

微塑料是一种普遍存在的环境污染物，其分布与土地利用和人口密度有关。尽管有许多研究对环境中的微塑料进行了量化，但当地的研究有助于提供信息，途径和政策。在这里，我们测量了切萨皮克湾（美国最大的河口）上地表水中微塑料的浓度。用蝠ta拖网从整个切萨皮克湾收集了30个地表水样品。手工处理样品中的微塑料和其他人为颗粒。傅里叶变换红外光谱（FTIR）用于确定颗粒的化学组成。在主要城市附近以及较大的河流或支流与切萨皮克湾相遇的地方，浓度较高。片段，电影，纤维是最常见的形态，聚乙烯和聚丙烯是最常见的塑料类型。这些结果可用于为切萨皮克湾地区的微塑料污染缓解策略提供信息。