Microplastics are a global environmental issue contaminating aquatic and terrestrial environments. They have been reported in atmospheric deposition, and indoor and outdoor air, raising concern for public health due to the potential for exposure. Moreover, the atmosphere presents a new vehicle for microplastics to enter the wider environment, yet our knowledge of the quantities, characteristics and pathways of airborne microplastics is sparse. Here we show microplastics in atmospheric deposition in a major population centre, central London. Microplastics were found in all samples, with deposition rates ranging from 575 to 1008 microplastics/m2/d. They were found in various shapes, of which fibrous microplastics accounted for the great majority (92%). Across all samples, 15 different petrochemical-based polymers were identified. Bivariate polar plots indicated dependency on wind, with different source areas for fibrous and non-fibrous airborne microplastics. This is the first evidence of airborne microplastics in London and confirms the need to include airborne pathways when consolidating microplastic impacts on the wider environment and human health.

中文翻译：

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城市环境中的大气微塑料沉积和交通评价。

微塑料是污染水生和陆地环境的全球环境问题。据报道，它们存在于大气沉降以及室内和室外空气中，由于暴露的可能性，引起了公众健康的关注。此外，大气为微塑料进入更广泛的环境提供了一种新的载体，但我们对空气中微塑料的数量、特征和途径的了解却很少。在这里，我们展示了伦敦市中心主要人口中心大气沉降中的微塑料。在所有样品中都发现了微塑料，沉积速率从 575 到 1008 个微塑料/m2/d 不等。它们以各种形状被发现，其中纤维微塑料占绝大多数（92%）。在所有样品中，鉴定出 15 种不同的石化聚合物。双变量极坐标图表明对风的依赖性，纤维和非纤维空气中的微塑料具有不同的来源区域。这是伦敦空气中微塑料的第一个证据，并证实了在巩固微塑料对更广泛的环境和人类健康的影响时需要包括空气传播的途径。