Microplastics fingerprinting at the watershed scale: from sources to receivers

塑料污染是一种全球性的、日益严重的环境危害，对食物网、生物多样性、生态系统服务和人类福祉具有潜在的深远影响。特别值得关注的是微塑料，因为它们的小尺寸增强了它们的远距离运输，对生物群的毒性以及吸附和浸出污染物的能力，包括有机污染物和有毒金属。我们建议实施一项全面的数据采集和建模策略，将整个流域规模的微塑料的来源、运输、归宿和暴露风险联系起来。除了已建立的光谱和成像技术，我们还将探索新型生物传感器和微波传感技术，用于环境样品中微塑料的快速筛选和分型。我们将改进微塑料组合体大型分析数据集的处理，并为微塑料的采样、样品制备、筛选、分析、数据处理和数据管理制定标准化工作流程。这些工作流程将被应用于描述河流网络的进入路径和沿河流网络的运输沿着，确定（生物）降解代理，量化水库和河岸的积累，并估计微塑料向接收湖泊的出口。过去的微塑料污染将从过时的沉积物岩心中重建，而在可变水文气象条件下对微塑料负荷和运输速率的分析将有助于预测未来更极端降水事件的影响。我们不断增长的数据库将被集成到一个质量平衡建模平台中，该平台将实现广泛的情景测试，包括微塑料排放和负载对假设源减排措施的响应。设想方案的结果，连同成本效益分析和与利益攸关方的知识交流，将有助于确定能够有效保护淡水生态系统和饮用水源免受微塑料污染的政策工具和治理方法。

Plastics pollution is a global and growing environmental hazard with potentially far-reaching consequences for food webs, biodiversity, ecosystem services and human well-being. Of particular concern are microplastics because their small sizes enhance their long-range transport, toxicity to biota, and capacity to sorb and leach contaminants, including organic pollutants and toxic metals. We propose to implement a holistic data acquisition and modeling strategy that will link the sources, transport, fate and exposure risks of microplastics at the scale of entire watersheds. In addition to established spectroscopic and imaging techniques, we will explore novel biosensors and microwave sensing for the rapid screening and typing of microplastics in environmental samples. We will improve the processing of large analytical datasets on microplastics assemblages and develop standardized workflows for the sampling, sample preparation, screening, analysis, data processing and data management of microplastics. These workflows will be applied to characterize the entry pathways to, and transport along, the river network, identify (bio)degradation proxies, quantify accumulation in reservoirs and on riverbanks, and estimate the export of microplastics to receiving lakes. Past microplastics pollution will be reconstructed from dated sediment cores while the analysis of microplastics loading and transport rates under variable hydrometeorological conditions will help forecast the impacts of more extreme precipitation events in the future. Our growing database will be integrated into a mass balance modeling platform that will enable extensive scenario testing, including the response of microplastics emissions and loadings to hypothetical source reduction measures. The scenario results, together with cost-benefit analyses and knowledge exchanges with stakeholders, will contribute to identifying policy instruments and governance approaches that can effectively protect freshwater ecosystems and drinking water sources from microplastics pollution.