Fate of the fungicide dodemorph during anaerobic digestion of biological waste

• Published in: Chemosphere (Oxford) Vol. 53; no. 5; pp. 505 - 514
• Main Authors: Vorkamp, Katrin, Taube, Jörg, Dilling, Jörg, Kellner, Esther, Herrmann, Reimer
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.11.2003; Elsevier
• Subjects: Anaerobic digestion; Anaerobiosis; Applied sciences; Bacteria, Anaerobic - metabolism; Biodegradation, Environmental; Biological and medical sciences; Biological treatment of sewage sludges and wastes; Biotechnology; Bound residues; Dissolved organic carbon; dodemorph; Environment and pollution; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Fungicides, Industrial - chemistry; Hydrogen-Ion Concentration; Industrial applications and implications. Economical aspects; Morpholines - chemistry; Partitioning; Pesticide residues; Pollution; Sewage - chemistry; Urban and domestic wastes; Waste Products - analysis; Wastes; Dissolved organic carbon; Bound residues; Partitioning; Pesticide residues; Anaerobic digestion; Organic matter; Pollutant behavior; Waste treatment; Pesticides; Morpholine derivatives; Fungicide; Operating conditions; Vegetal waste; Food waste; Persistence; pH; Biological wastes; Phase partition; Biological treatment
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/S0045-6535(03)00544-7

The aim of this study was to examine the stability and distribution of the fungicide dodemorph during anaerobic digestion of biological waste, including a short subsequent aerobic treatment. Three reactor experiments were conducted. The influences of pH and dissolved organic carbon (DOC) were further studied in batch experiments. The reactor experiments showed no decrease in the concentration of dodemorph, indicating stability of the fungicide. In connection with the results of the batch experiments, a clear pH-dependency of the partitioning of dodemorph between solid and water phase could be shown. At pH values below the p K a value of 7.8, protonated dodemorph molecules predominate. However, a release into the water phase was only observed at pH values of 5 and below. It can be assumed that in the pH range between 5 and 7.8 dodemorph forms bonds with carboxyl groups of organic matter. Dodemorph was not completely extractable from the solid waste matrix due to strong bonds with the organic matter. Solubilising effects by water ingredients of the process water were not apparent.