Evaluation of micro- and nanoplastics in Canadian drinking water, their role as vectors of pathogen and chemical transport and associated health risks

饮用水处理是为了在饮用前去除物理、化学和生物污染物。加拿大各地已经实施了相关法规，以降低健康风险，并确保向消费者提供清洁、安全的饮用水。最近，在对来自世界各地的经过处理的饮用水的有限研究中发现了微塑料和纳米塑料，对消费者构成了未知的风险。微塑料被定义为大小在1到5,000微米之间的合成聚合物；纳米塑料代表大小为1微米的颗粒。尽管人们普遍认为许多水源水被微塑料和纳米塑料不可逆转地污染，但加拿大各地采用的传统和先进的水处理工艺对它们的去除知之甚少。因此，目前尚不清楚与这些颗粒物的消费相关的潜在健康影响。 这项拟议的研究将检查加拿大各地设施中未经处理的原水和经处理的水中微塑料和纳米塑料的浓度和特征。在这一初步数据收集之后，这项研究的重点将是填补与饮用水中微塑料和纳米塑料消费相关的潜在健康影响相关的知识空白。人们假设塑料颗粒可以运输化学和生物(例如病原体)污染物。这项研究将有助于量化化学吸附到不同大小的原始和环境风化塑料颗粒上的生物膜的发展和组成，并对其进行表征。从微塑料和纳米塑料中提取的污染物还将通过一系列基于细胞的生物检测进行检查，以评估潜在的毒性途径。这项研究代表了对加拿大饮用水中微塑料和纳米塑料进行的最全面的检查，并将对塑料上的化学和生物污染进行深入评估。

Drinking water treatment is conducted to remove physical, chemical and biological contaminants prior to consumption. Regulations have been implemented across Canada to reduce health risks and ensure clean, safe drinking water is provided to consumers. Micro- and nanoplastics have recently been identified in limited studied of treated drinking waters from around the world, posing an unknown risk to consumers. Microplastics are defined as synthetic polymers between 1 and 5,000 µm in size; nanoplastics represent particles which measure <1 µm. Although it has been widely accepted that many source waters are irreversibly contaminated with micro- and nanoplastics, their removal by conventional and advanced water treatment processes employed across Canada is poorly understood. As such, the potential health impacts associated with the consumption of these particles is currently unknown. The proposed research will examine the concentration and characteristics of micro- and nanoplastics in raw (untreated) and treated water at facilities across Canada. Following this initial data collection, the emphasis of this research will be to fill the knowledge gap associated with the potential health impacts related to consumption of micro- and nanoplastics in drinking water. It has been hypothesized that plastic particles may transport chemical and biological (e.g. pathogen) contaminants. This research will serve to quantify chemical sorption to and characterize biofilm development and composition on virgin and environmentally weathered plastic particles of various sizes. Contaminants extracted from the micro- and nanoplastics will also be examined through a series of cell-based bioassays to evaluate potential toxicity pathways. This research represents the most comprehensive known examination of micro- and nanoplastics in Canadian drinking water and will provide an in-depth evaluation of chemical and biological contamination on plastics.