Biocides used as antifoulants in paints and renders are leached off of building facades by rain and thereby end up in natural environments. It can be assumed such compounds can be harmful to the ecosystems in the receiving waters, but that they could also be degraded by the microbial activity in the sediments.

A series of tests was performed on sediments from two stormwater detention ponds, one in Aarhus and one in Silkeborg. The potential of these sediments for sorption and biodegradation of biocides Diuron, Terbutryn and Cybutryn was tested in a suspension experiment. Sorption was also studied in intact sediment cores and additional tests were conducted to measure the possible inhibition caused by the biocide dosing to the microbial populations present in the samples. The results indicate the biocides can be degraded in the sediments, and showed microbial inhibition by at least one of the tested biocides.