Grant: Strategic Projects - Group

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.