Environmental risks associated with nanoparticulate silver used as biocide
Nanosilver is increasingly used as a biocide inmany applications such as textile fibres, food containers,medical devices and coatings of daily-use items. At thesame time, there are applications of biocidal silver thathave been in use for many years, including silverformulations 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 silveremissions from other sources. We review recent informationabout nanosilver uses and emissions to the aquaticenvironment and about the environmental fate and toxicityof nanosilver. On this basis, we discuss perspectives for anenvironmental risk assessment of nanosilver and identify keyquestions to be addressed in such an assessment. Ourconclusion is that currently environmental risks caused bynanosilver applications are probably low, but that the rapidgrowth of the use of silver as a biocide necessitates morestudy of sources, fate and transport, and toxicity ofenvironmentally relevant forms of silver.