Voorspelling van de biodegradatie van gesubstitueerde monocyclische aromaten in de bodem

Abstract

The project "Prediction of the biodegradation of substituted monocyclic aromatic compounds in soils" has resulted in the development of the model SPAR (Soil Properties Activity Relationship), which describes the initial and maximal biodegradation rate of chlorophenols and chloroanilines in various natural soils. Major part of this report is dedicated to the description of experiments and model formulation and performance. It appeared that the variation in biodegradation rates between soils could be described by a Michaelis-Menten equation with a sorption-corrected dosage (pore water concentration) and a pH-dependent Vmax. The model was used to calculate the biodegradation potential of soils of the European Community and the Netherlands. In the last chapter results of other parts of the research are summarized to give an overview of the project "Prediction of the biodegradation of substituted monocyclic aromatic compounds in soils". It appeared that bound residue formation is related to the soil organic matter content. Chloroanilines showed different affinities for fulvic acids, humic acids and humine. A second chlorinesubstituent decreased bound residue formation. Bound residues were not as inaccessible as we expected, 6-10% of the soil-bound 4-monochloroaniline-residue was mineralized by microbiological activity. The effect of pentachlorophenol on the mineralization rate of 4-MCP was studied. The combination of these data with a biodegradation QSAR would be a relevant extension of SPAR, for prediction of biodegradation rates of combinations of xenobiotic compounds.<br>