This Formas project aims at assessing the benefits and possible environmental risks associated with blackwater treatment and use as fertilizer in agricultural fields.
Treatment and use of blackwater (faeces, urine and flush toilet water) offer several advantages, such as the recovery of a nutrient-rich agricultural product and closing of the nutrient loop. Nevertheless, blackwater may contain high levels of pharmaceuticals and active metabolites as well as bacteria carrying antibiotic-resistant genes (ARGs). Therefore, before usage, appropriate treatment and sanitation is needed to avoid the spread of these harmful pollutants in the environment.
This project will evaluate state-of-the-art blackwater treatment techniques, focusing on the removal of pharmaceutical residues and on the reduction of ARGs. We will also conduct field monitoring campaigns on sites where blackwater, manure and sludge have been amended. In the end of the project a theoretical risk assessment study will be carried out. The studies will be used to investigate whether use of blackwater is a significant vector of dissemination of these pollutants in the environment and to assess environmental hazards posed by different agricultural practices.
The outcome of this project will help to guarantee a safe use of this natural resource.
SLU: Foon Yin Lai, Lutz Ahrens, Karin Wiberg
ICRA, Girona, Spain: Meritxell Gros