Plastic waste is everywhere and the tinier the plastic is the harder it is to deal with. These microplastics are proving to be very difficult to address which has sent researchers looking into all sort of solutions. One solution is already up and running in some places: sand filters in water systems. It turns out that some existing sand filtration systems can capture plastic nano particles.
The results are now in, and they include some reassuring findings. In a report published today in the Journal of Hazardous Materials, the researchers show that even if untreated water contained considerable quantities of nanoplastics, these particles were retained in sand filters very efficiently during water treatment. Both in laboratory tests and in a larger test facility located directly on the premises of the Zurich Water Works, the biologically active slow sand filter was the most effective at retaining nanoparticles – achieving an efficacy level in the region of 99.9%.