We can't find the internet
Attempting to reconnect
Something went wrong!
Hang in there while we get back on track
Microlitter in sewage treatment systems
Summary
A study of Swedish sewage treatment plants found that municipal wastewater contains substantial amounts of microplastics, but most particles are captured in sewage sludge during treatment rather than discharged to waterways. However, when sludge is spread on farmland as fertilizer, these microplastics still reach the environment, suggesting that household-level reduction is ultimately needed.
The report presents results from a study on the role municipal sewage treatment plants (STPs) have as entrance routes for microplastics and other microlitter particles to the marine environment. Microlitter concentrations were analysed in waste water before and after treatment in the STPs, and in the recipient waters where the treated waste water is discharged. Municipal waste water was found to contain a substantial amount of microlitter, but in STPs equipped with chemical and biological treatment most of the litter particles were retained in the sewage sludge. This reduces the impact on the recipient water, but if the sludge is used as fertilizer on farm land the microlitter will still reach the environment. Efforts to reduce the microlitter concentrations should therefore preferably be done in households and other locations where the waste water is originally being formed.