Antibiotics in biogas plants

Active pharmaceutical substances, in particular antibiotics, are used in livestock farming in considerable quantities and can also be found in farm manure. When these fertilisers are used in biogas plants, these active substances can influence the degradation process and the formation of biogas or methane gas. In this report, the Federal Environment Agency examines the behaviour of antibiotic agents in biogas plants and their effects on the fermentation process. Soils fertilised with fermentation residues from these plants were also analysed. It appears that manure contaminated with antibiotics interferes with the bioga process and that methane gas production is already reduced at concentrations of less than 50 mg/kg. These active substances were also found in the soils fertilised with fermentation residues.