Tracking silver nanomaterials in the aquatic environment

目前，可以通过简单的湿化学方法制备纳米银颗粒，目前主要应用于食品包装材料、防臭纺织品、运动装备、电子和家用电器、化妆品和医疗器械。尽管它们在许多国家的家庭和工业用途很广泛，但人们对它们在水生和陆地环境中的命运和有毒行为知之甚少。我们的目标是确定工程银纳米材料从其工业和家庭来源到各种环境隔间(淡水和微咸水、悬浮颗粒物、沉积物和生物群)的路径。重点研究了光、离子强度和有机物等环境变量对银纳米材料聚集和转化的影响。我们的主要研究策略包括分析城市废水中的银纳米材料，合成模型银纳米颗粒以阐明银向生物舱的转移，利用大体积介观模拟银颗粒与天然淡水和海水的混合过程，以及研究银实体与溶解有机物、模型生物膜和浮游植物细胞的相互作用。预期的结果将对联邦和省级环境机构有用，因为他们必须很快决定如何在监管背景下处理工程纳米颗粒。这项研究将对行业和环境监管机构都有好处。工业界将更好地了解纳米银在水环境中的生物可利用性，并将受益于在讨论工程纳米材料水质标准的理论基础时环境监管机构的可信度增加。预期的结果对有意为加拿大五大湖和圣劳伦斯河制定水和沉积物质量标准的环境监管机构也应具有实际和直接的重要性。

Nowadays, nano-sized silver particles can be prepared by simple wet chemistry and their main current applications are food packaging materials, odor-resistant textiles, sport gear, electronics and household appliances, cosmetics and medical devices. Although their domestic and industrial uses are widespread in many countries, little is known about their fate and toxic action in aquatic and terrestrial environments. Our objective is to determine the pathways taken by engineered silver nanomaterials from their industrial and domestic sources to various environmental compartments (fresh and brackish waters, suspended particulate matter, sediment and biota). Impacts of environmental variables such as light, ionic strength and organic matter on the aggregation and transformation of silver nanomaterials are particularly investigated. Our main research strategies include the analysis of silver nanomaterials in urban wastewaters, synthesis of model silver nanoparticles to elucidate silver transfer to biological compartments, experimental work mimicking the mixing process of silver particles with natural fresh and sea water using large volume mesocosms, and studies of the interactions of silver entities with dissolved organic matter, model biological membranes and phytoplankton cells. The anticipated results will be of use to Federal and Provincial environmental agencies as they have to decide very soon how to handle engineered nanoparticles in a regulatory context. This research will be of benefit to both industry and environmental regulators. Industry will gain a better appreciation of the bioavailability of nanoparticulate silver in the aquatic environment and will benefit from increased credibility vis-à-vis environmental regulators when discussing the rationale for water quality criteria for engineered nanomaterials. The anticipated results should also be of practical and immediate importance to environmental regulators who are interested in establishing water and sediment quality criteria for the Canadian Great Lakes and St. Lawrence River.