A study conducted by our network partner Prof Dr Christian Laforsch and his colleague Prof Dr Ruth Freitag (Department of Bioprocess Engineering of the University of Bayreuth) takes a closer look at plastic residue in organic waste. The latter is exploited in biogas plants and afterwards processed to produce organic fertilizer. The fertilizer is spread on the fields, with plastic particles getting into agricultural soil and waters.
Waste from private households contained the highest amount of plastic particles – mostly polystyrene or polyethylene, which are common as packaging materials. Biogas plants operating with organic waste from industry and trade face a high share of polyesters. These plastics are used to package and transport fruit and vegetables. The research comprised particles in a size range between 1 and 5 millimeters.
Illustration: Sarah Piehl