UMSICHT – Assessment of the environmental hazards of silver nanomaterials: From chemical particles to technical products
The UMSICHT project was dedicated to obtaining a better understanding of the behaviour, fate, and impact of silver nanoparticles in the environment. Using standardised, optimised or newly developed procedures, the dissolution behaviour, transport behaviour, stability, and effects on living organisms in inshore waters and soils of differently manufactured particles were investigated under different conditions.
As an example of consumer products, silver nanoparticles in textiles were analysed investigating particle, fibre and fabric production through to abrasion and washing features and disposal in sewage treatment plants.
It became clear that the type of textile production decides on whether and in what quantities the particles get into the environment: In the ideal case, almost no and in the worst case almost all particles are being released. As silver nanoparticles are not completely retained in the sewage treatment plant, a small part may reach inshore waters, whereas the major part will end up in the soil through the usage of sewage sludge in agriculture.
The nanoparticles or the silver dissolved from them proved to be highly toxic for almost all investigated microorganisms. On the other hand, the quantities that finally end up in the environment are comparatively small. As silver cannot be degraded, however, it cannot be excluded that within decades to centuries, soil organisms will get damaged. This applies in particular to residues from imported products where neither the production method nor the amounts of contained silver nor the production quantities are known. It was found that the complexity of the product market is the major obstacle to reliable forecasts.
