Environmental risks associated with nanoparticulate silver used as biocide§


*Corresponding author

1. Institute for Chemical and Bioengineering, ETH Zürich, Wolfgang-Pauli-Str. 10, Zürich, CH-8093, Switzerland

2. Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstr. 133, Dübendorf, CH-8600, Switzerland


Nanosilver is increasingly used as a biocide in many applications such as textile fibres, food containers, medical devices and coatings of daily-use items. At thesame time, there are applications of biocidal silver that have been in use for many years, including silver formulations that contain nanoscale silver particles that areused for water disinfection. In this situation, the questionneeds to be clarified whether nanosilver applications leadto human and environmental exposure and, subsequently, toxic effects that are different from those caused by silver emissions from other sources. We review recent informationabout nanosilver uses and emissions to the aquatic environment and about the environmental fate and toxicity of nanosilver. On this basis, we discuss perspectives for anenvironmental risk assessment of nanosilver and identify key questions to be addressed in such an assessment. Ourconclusion is that currently environmental risks caused by nanosilver applications are probably low, but that the rapid growth of the use of silver as a biocide necessitates more study of sources, fate and transport, and toxicity of environmentally relevant forms of silver.