Development and Implementation of a Nanoplastic Analysis Method for Drinking Water

在加拿大和世界各地的饮用水系统中发现了微塑料。由于饮用经处理的饮用水中的微小塑料颗粒可能带来潜在的健康风险，加州州已开始对“饮用水中的微塑料”的定义进行规范，沿着提出后续测试要求，预计加拿大监管机构将遵循这一进程。与之前对微塑料的定义不同，该定义规定了1 µm的较低尺寸阈值，加州采用的定义要求在2021年7月1日之前对三维尺寸小至1 nm的颗粒进行量化和表征（即比之前考虑的小1000倍）。虽然加入更小的颗粒将确保更好地保护人类健康，并提供更好地了解塑料污染和改进对特定工艺塑料去除的评估，但目前没有分析方法可以准确和可重复地测量饮用水中的纳米塑料。 拟议的研究将建立在多伦多大学饮用水研究小组最近完成的关于通过将其扩展到检查小至1 nm的颗粒来表征和量化>1 µm微塑料的方法开发的基础上。最初，这项工作将通过对现有文献进行审查，确定可能最适合纳米塑料表征和定量的分析方法。在方法选择和优化之后，将完成样品制备和分析。为确保结果准确且可重现，将实施严格的质量保证和质量控制程序（QA/QC），以最大限度地减少背景污染的影响，并解决任何饮用水基质特异性干扰。这项研究是保护加拿大饮用水供应的重要一步，有助于确保研究人员、饮用水公用事业和监管机构拥有必要的工具，在未来提供清洁、安全的饮用水。

Microplastics have been identified in drinking water systems across Canada and around the world. As a result of the potential health risks associated with the consumption of microscopic plastic particles in treated drinking water, the State of California has begun the process of regulating a definition of "Microplastics in Drinking Water" along with subsequent testing requirements, a process which is anticipated to be followed by Canadian regulators. Unlike previous definitions of microplastics which specified a lower-size threshold of 1 µm, the definition adopted by California requires quantification and characterization of particles as small as 1 nm in three dimensions (i.e. 1000 times smaller than previously considered) by July 1, 2021. Although the incorporation of smaller particles will ensure greater protection of human health, as well as provide a better understanding of plastic contamination and an improved evaluation of process specific plastic removals, no analytical method is currently available to accurately and reproducibly measure nanoplastics in drinking water. The proposed research will build upon that recently completed by the Drinking Water Research Group at the University of Toronto regarding method development for the characterization and quantification of microplastics >1 µm by extending it to examine particles as small as 1 nm. Initially, this work will identify analytical methods which may be most appropriate for characterization and quantification of nanoplastics by conducting a review of existing literature. Following method selection and optimization, sample preparation and analysis will be completed. To ensure that the results are both accurate and reproducible, rigorous quality assurance and quality control procedures (QA/QC) will be implemented to minimize the impacts of background contamination and address any drinking water matrix-specific interference. This research represents an essential step in the protection of Canadian drinking water supplies, by helping to ensure that researchers, drinking water utilities and regulatory authorities have the tools necessary to provide clean, safe drinking water in the future.