How do silver nanoparticles impact the composting of municipal solid waste?

(Nanowerk News) Like many other nanoparticles, silver nanopartciles (AgNPs) have the potential for release into the environment throughout their life cycle. At the end of their useful life, products containing nanoparticles are often disposed of with the municipal solid waste stream. In a disposal scenario, nanoparticles (e.g., AgNPs) may leach from products into the solid waste.
silver nanoparticles in compost
A new study study ("The Impact of Silver Nanoparticles on the Composting of Municipal Solid Waste") conducted by scientists at the University of Cincinnati and the U.S. Environmental Protection Agency, aimed at investigating the impacts of polyvinylpyrrolidone (PVP) coated silver nanoparticles (PVP-AgNPs) on the composting process of the biodegradable organic fraction of municipal solid waste. This research represents one of the few studies that evaluate end-of-life management concerns with regard to the increasing use of nanomaterials in everyday life.
The study also examines relatively low concentrations that may be encountered in a real world scenario and how such exposure may impact the function and composition of microbial communities associated with compost samples.
The team found that the AgNPs evaluated in their study did not significantly influence aerobic composting processes at the concentrations that could be expected to be present in the solid waste stream.
The researchers conclude that, extrapolating from their results, similar toxicological behavior of AgNPs would be expected in the organically rich municipal solid waste landfills if the concentration of AgNPs was relatively low.
They also point out, though, that additional research, however, is still needed to identify at which concentrations AgNPs start to have toxicological impact on waste management systems where microbial groups and microbial processes may be more impacted by AgNPs.
Source: American Chemical Society