Prediction of chemicals biodegradation in soils: a tentative of modeling

Natural attenuation of organic pollutants in the environment is controlled mainly by three groups of parameters: (i) environmental characteristics (e. g., soil organic matter), (ii) chemical characteristics (e.g., hydrophobici ty of the pollutant, structure etc.) and (iii) nature and density of biodeg raders. Potential parameters describing environmental characteristics and chemical characteristics were collected from the literature and stored into a data b ase. Using multiple linear regressions, we have expressed the observed half -life of chemicals as a function of environmental and chemical characterist ics. Models demonstrate that environment influences the prediction of the p ersistence time of molecules that have a predicted half-life of less than 1 50 days. Conversely, for molecules that are predicted to be less rapidly bi odegradable (i.e., t(1/2) > 150 days) environmental parameter variations on ly slightly modify (about 10%) their persistence times. (C) 1999 Elsevier S cience Ltd. All rights reserved.